NCBI Conserved Domain Search

Immunoglobulin (Ig) domain of Down Syndrome Cell Adhesion molecule (DSCAM); The members here are composed of the immunoglobulin (Ig) domain of Down Syndrome Cell Adhesion molecule (DSCAM). DSCAM is a cell adhesion molecule expressed largely in the developing nervous system. The gene encoding DSCAM is located at human chromosome 21q22, the locus associated with the intellectual disability phenotype of Down Syndrome. DSCAM is predicted to be the largest member of the IG superfamily. It has been demonstrated that DSCAM can mediate cation-independent homophilic intercellular adhesion.

Pssm-ID: 409398 Cd Length: 101 Bit Score: 225.06 E-value: 1.99e-68

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  785 KIPAMITSYPNTTLATQGQKKEMSCTAHGEKPIIVRWEKEDRIINP-EMARYLVSTKEVGEEVISTLQILPTVREDSGFF 863
Cdd:cd05735    1 KIPAMITSYPNTTLATKGQKKEMSCTAHGEKPIIVRWEKEDTIINPsEMSRYLVTTKEVGDEVISTLQILPTVREDSGFF 80

                         90       100
                 ....*....|....*....|.
gi 20127422  864 SCHAINSYGEDRGIIQLTVQE 884
Cdd:cd05735   81 SCHAINSYGEDRGIIQLTVQE 101

Immunoglobulin (Ig)-like domain of Down Syndrome Cell Adhesion molecule (DSCAM); The members here are composed of the immunoglobulin (Ig)-like domain of Down Syndrome Cell Adhesion molecule (DSCAM). DSCAM is a cell adhesion molecule expressed largely in the developing nervous system. The gene encoding DSCAM is located at human chromosome 21q22, the locus associated with the intellectual disability phenotype of Down Syndrome. DSCAM is predicted to be the largest member of the IG superfamily. It has been demonstrated that DSCAM can mediate cation-independent homophilic intercellular adhesion.

Pssm-ID: 409397 [Multi-domain] Cd Length: 97 Bit Score: 207.35 E-value: 2.46e-62

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  689 PPKFVVQPRDQDGIYGKAVILNCSAEGYPVPTIVWKFSKGAGVPQFQPIA-LNGRIQVLSNGSLLIKHVVEEDSGYYLCK 767
Cdd:cd05734    1 PPRFVVQPNDQDGIYGKAVVLNCSADGYPPPTIVWKHSKGSGVPQFQHIVpLNGRIQLLSNGSLLIKHVLEEDSGYYLCK 80

                         90
                 ....*....|....*..
gi 20127422  768 VSNDVGADVSKSMYLTV 784
Cdd:cd05734   81 VSNDVGADISKSMYLTV 97

Fifth immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fifth immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409550 [Multi-domain] Cd Length: 89 Bit Score: 139.24 E-value: 1.61e-38

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  504 PASIRPMKNITAIAGRDTYIHCRVIGYPYYSIKWYKNSNLLPFNHRQVAFeNNGTLKLSDVQKEVDEGEYTCNVLVQPQL 583
Cdd:cd20958    1 PPFIRPMGNLTAVAGQTLRLHCPVAGYPISSITWEKDGRRLPLNHRQRVF-PNGTLVIENVQRSSDEGEYTCTARNQQGQ 79

                         90
                 ....*....|
gi 20127422  584 STSQSVHVTV 593
Cdd:cd20958   80 SASRSVFVKV 89

Fourth immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409548 [Multi-domain] Cd Length: 96 Bit Score: 132.30 E-value: 4.45e-36

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  406 TPKIISAFSEKVVSPAEPVSLMCNVKGTPLPTITWTLDDDPILKGGSHRISQMITSEGNVVSYLNISSSQVRDGGVYRCT 485
Cdd:cd20956    1 APVLLETFSEQTLQPGPSVSLKCVASGNPLPQITWTLDGFPIPESPRFRVGDYVTSDGDVVSYVNISSVRVEDGGEYTCT 80

                         90
                 ....*....|....*.
gi 20127422  486 ANNSAGVVLYQARINV 501
Cdd:cd20956   81 ATNDVGSVSHSARINV 96

Seventh immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the seventh immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409546 [Multi-domain] Cd Length: 96 Bit Score: 110.87 E-value: 1.52e-28

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  689 PPKFVVQPRDQDGIYGKAVILNCSAEGYPVPTIVWKFSKGAGVPQFQPIALNGRIQVLSNGSLLIKHVVEEDSGYYLCKV 768
Cdd:cd20954    1 PPRWIVEPVDANVAAGQDVMLHCQADGFPTPTVTWKKATGSTPGEYKDLLYDPNVRILPNGTLVFGHVQKENEGHYLCEA 80

                         90
                 ....*....|....*.
gi 20127422  769 SNDVGADVSKSMYLTV 784
Cdd:cd20954   81 KNGIGSGLSKVIFLKV 96

Sixth immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the sixth immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409551 Cd Length: 94 Bit Score: 90.63 E-value: 2.11e-21

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  596 PPFIQPFEFPR--FSIGQRVFIPCVVVSGDLPITITWQKDGRPIPGSLGVTIDNID-FTSSLRISNLSLMHNGNYTCIAR 672
Cdd:cd20959    1 PPRIIPFAFGEgaAQVGMRAQLHCGVPGGDLPLNIRWTLDGQPISDDLGITVSRLGrRSSILSIDSLEASHAGNYTCHAR 80

                         90
                 ....*....|....
gi 20127422  673 NEAAAVEHQSQLIV 686
Cdd:cd20959   81 NSAGSASYTAPLTV 94

Fibronectin type 3 domain; One of three types of internal repeats found in the plasma protein fibronectin. Its tenth fibronectin type III repeat contains an RGD cell recognition sequence in a flexible loop between 2 strands. Approximately 2% of all animal proteins contain the FN3 repeat; including extracellular and intracellular proteins, membrane spanning cytokine receptors, growth hormone receptors, tyrosine phosphatase receptors, and adhesion molecules. FN3-like domains are also found in bacterial glycosyl hydrolases.

Pssm-ID: 238020 [Multi-domain] Cd Length: 93 Bit Score: 81.77 E-value: 2.21e-18

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1380 PDQPR-LTVSKTTSSSITLSWLPGDNGGSSIRGYILQYSEDNSEQWGSFPISP-SERSYRLENLKCGTWYKFTLTAQNGV 1457
Cdd:cd00063    1 PSPPTnLRVTDVTSTSVTLSWTPPEDDGGPITGYVVEYREKGSGDWKEVEVTPgSETSYTLTGLKPGTEYEFRVRAVNGG 80

                         90
                 ....*....|...
gi 20127422 1458 GPGRISEIIEAKT 1470
Cdd:cd00063   81 GESPPSESVTVTT 93

Fibronectin type III domain;

Pssm-ID: 394996 [Multi-domain] Cd Length: 85 Bit Score: 78.23 E-value: 3.06e-17

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422   1381 DQPR-LTVSKTTSSSITLSWLPGDNGGSSIRGYILQYSEDNSEQ-WGSFPISPSERSYRLENLKCGTWYKFTLTAQNGVG 1458
Cdd:pfam00041    1 SAPSnLTVTDVTSTSLTVSWTPPPDGNGPITGYEVEYRPKNSGEpWNEITVPGTTTSVTLTGLKPGTEYEVRVQAVNGGG 80


                   ....*
gi 20127422   1459 PGRIS 1463
Cdd:pfam00041   81 EGPPS 85

Fibronectin type 3 domain [General function prediction only];

Pssm-ID: 442628 [Multi-domain] Cd Length: 603 Bit Score: 85.44 E-value: 1.81e-16

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  937 DVSPQLNSATIIDIHPSSTYSIRMYAKNRIGKSEPSNELTITADEAAPDgPPQEVHLEPISSQSIRVTWKAPKkhlqNGI 1016
Cdd:COG3401  186 TVTSTTLVDGGGDIEPGTTYYYRVAATDTGGESAPSNEVSVTTPTTPPS-APTGLTATADTPGSVTLSWDPVT----ESD 260

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1017 IRGYQIgYREYSTGGNFQfniiSVDTSGDSEvYTLDNLNKFTQYGLVVQACNRAGTGPSSQEIITTTLEDVPSYPPENVQ 1096
Cdd:COG3401  261 ATGYRV-YRSNSGDGPFT----KVATVTTTS-YTDTGLTNGTTYYYRVTAVDAAGNESAPSNVVSVTTDLTPPAAPSGLT 334

                        170       180       190       200       210       220       230       240
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1097 AIATSPESISISWStlskEALNGILQGFRvIYWANLMDGELGEIkNITTTQPSLELDGLEKYTNYSIQVLAFTRAGDG-- 1174
Cdd:COG3401  335 ATAVGSSSITLSWT----ASSDADVTGYN-VYRSTSGGGTYTKI-AETVTTTSYTDTGLTPGTTYYYKVTAVDAAGNEsa 408

                        250       260       270       280       290       300       310       320
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1175 ----VRSEQIFTRTKEDVPGPPAGVKAAAASASMVFVSWLPPLKLNGIIRKYTVFC-SHPYPTVISEFEASPDSFSYrip 1249
Cdd:COG3401  409 pseeVSATTASAASGESLTASVDAVPLTDVAGATAAASAASNPGVSAAVLADGGDTgNAVPFTTTSSTVTATTTDTT--- 485

                        330       340       350       360       370
                 ....*....|....*....|....*....|....*....|....*....|.
gi 20127422 1250 nlsrnrqYSVWVVAVTSAGRGNSSEIITVEPLAKAPARILTFSGTVTTPWM 1300
Cdd:COG3401  486 -------TANLSVTTGSLVGGSGASSVTNSVSVIGASAAAAVGGAPDGTPN 529

Immunoglobulin I-set domain;

Pssm-ID: 400151 [Multi-domain] Cd Length: 90 Bit Score: 72.68 E-value: 3.31e-15

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422    235 KAMAGQRVELPCKALGHPEPDYRWLKDNMPLELSGRFQKTVTG----LLIENIRPSDSGSYVCEVSNRYGTAKVIGRLYV 310
Cdd:pfam07679   11 EVQEGESARFTCTVTGTPDPEVSWFKDGQPLRSSDRFKVTYEGgtytLTISNVQPDDSGKYTCVATNSAGEAEASAELTV 90

Immunoglobulin domain; This family contains immunoglobulin-like domains.

Pssm-ID: 464046 [Multi-domain] Cd Length: 78 Bit Score: 71.83 E-value: 4.30e-15

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422    689 PPKFVVQPRDQDGIYGKAVILNCSAEGYPVPTIVWKFSKGAGVPQFQPIalngRIQVLSNGSLLIKHVVEEDSGYYLCKV 768
Cdd:pfam13927    1 KPVITVSPSSVTVREGETVTLTCEATGSPPPTITWYKNGEPISSGSTRS----RSLSGSNSTLTISNVTRSDAGTYTCVA 76


                   ..
gi 20127422    769 SN 770
Cdd:pfam13927   77 SN 78

First immunoglobulin (Ig)-like domain in neogenin, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain in neogenin and related proteins. Neogenin is a cell surface protein which is expressed in the developing nervous system of vertebrate embryos in the growing nerve cells. It is also expressed in other embryonic tissues and may play a general role in developmental processes such as cell migration, cell-cell recognition, and tissue growth regulation. Included in this group is the tumor suppressor protein DCC which is deleted in colorectal carcinoma. DCC and neogenin each have four Ig-like domains followed by six fibronectin type III domains, a transmembrane domain, and an intracellular domain. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409387 Cd Length: 97 Bit Score: 71.74 E-value: 8.17e-15

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  692 FVVQPRDQDGIYGKAVILNCSAEGYPVPTIVWKFSkgaGVpqFQPIALNGRIQVLSNGSLLIKHVV-----EEDSGYYLC 766
Cdd:cd05722    4 FLSEPSDIVAMRGGPVVLNCSAESDPPPKIEWKKD---GV--LLNLVSDERRQQLPNGSLLITSVVhskhnKPDEGFYQC 78

                         90
                 ....*....|....*....
gi 20127422  767 KVSN-DVGADVSKSMYLTV 784
Cdd:cd05722   79 VAQNeSLGSIVSRTARVTV 97

Second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of the Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit-2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409389 [Multi-domain] Cd Length: 87 Bit Score: 70.51 E-value: 1.95e-14

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  694 VQPRDQDGIYGKAVILNCSA-EGYPVPTIVWKfSKGagvpqfQPIAL-NGRIQVLSNGSLLIKHVVEEDSGYYLCKVSND 771
Cdd:cd05724    2 VEPSDTQVAVGEMAVLECSPpRGHPEPTVSWR-KDG------QPLNLdNERVRIVDDGNLLIAEARKSDEGTYKCVATNM 74

                         90
                 ....*....|...
gi 20127422  772 VGADVSKSMYLTV 784
Cdd:cd05724   75 VGERESRAARLSV 87

Fibronectin type 3 domain; One of three types of internal repeats found in the plasma protein fibronectin. Its tenth fibronectin type III repeat contains an RGD cell recognition sequence in a flexible loop between 2 strands. Approximately 2% of all animal proteins contain the FN3 repeat; including extracellular and intracellular proteins, membrane spanning cytokine receptors, growth hormone receptors, tyrosine phosphatase receptors, and adhesion molecules. FN3-like domains are also found in bacterial glycosyl hydrolases.

Pssm-ID: 238020 [Multi-domain] Cd Length: 93 Bit Score: 70.22 E-value: 2.60e-14

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  885 PPDPPEIEIKDVKARTITLRWTMGFDGNSPITGYDIECKNKSDswDSAQRTKDVSPQLNSATIIDIHPSSTYSIRMYAKN 964
Cdd:cd00063    1 PSPPTNLRVTDVTSTSVTLSWTPPEDDGGPITGYVVEYREKGS--GDWKEVEVTPGSETSYTLTGLKPGTEYEFRVRAVN 78

                         90
                 ....*....|....
gi 20127422  965 RIGKSEPSNELTIT 978
Cdd:cd00063   79 GGGESPPSESVTVT 92

Immunoglobulin I-set domain;

Pssm-ID: 400151 [Multi-domain] Cd Length: 90 Bit Score: 69.59 E-value: 3.78e-14

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422    690 PKFVVQPRDQDGIYGKAVILNCSAEGYPVPTIVWkFSKGagvpqfQPIALNGRIQVLSNG---SLLIKHVVEEDSGYYLC 766
Cdd:pfam07679    1 PKFTQKPKDVEVQEGESARFTCTVTGTPDPEVSW-FKDG------QPLRSSDRFKVTYEGgtyTLTISNVQPDDSGKYTC 73

                           90
                   ....*....|....*...
gi 20127422    767 KVSNDVGADvSKSMYLTV 784
Cdd:pfam07679   74 VATNSAGEA-EASAELTV 90

First immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the first immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409547 Cd Length: 99 Bit Score: 69.75 E-value: 4.77e-14

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422   26 FVNASLQEVVFASTTGTLVPCPAAGIPPVTLRWYLATGEEIYDVPGIRHVHPNGTLQIFPFPPSSFSTLIHDNTYYCTAE 105
Cdd:cd20955    4 FLKEPTNRIDFSNSTGAEIECKASGNPMPEIIWIRSDGTAVGDVPGLRQISSDGKLVFPPFRAEDYRQEVHAQVYACLAR 83

                         90
                 ....*....|....*.
gi 20127422  106 NPSGKIRSQDVHIKAV 121
Cdd:cd20955   84 NQFGSIISRDVHVRAV 99

Fibronectin type 3 domain; One of three types of internal repeat within the plasma protein, fibronectin. The tenth fibronectin type III repeat contains a RGD cell recognition sequence in a flexible loop between 2 strands. Type III modules are present in both extracellular and intracellular proteins.

Pssm-ID: 214495 [Multi-domain] Cd Length: 83 Bit Score: 68.80 E-value: 6.47e-14

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422    1380 PDQPR-LTVSKTTSSSITLSWLP--GDNGGSSIRGYILQYSEDNSEqWGSFPISPSERSYRLENLKCGTWYKFTLTAQNG 1456
Cdd:smart00060    1 PSPPSnLRVTDVTSTSVTLSWEPppDDGITGYIVGYRVEYREEGSE-WKEVNVTPSSTSYTLTGLKPGTEYEFRVRAVNG 79


                    ....
gi 20127422    1457 VGPG 1460
Cdd:smart00060   80 AGEG 83

Fibronectin type III domain;

Pssm-ID: 394996 [Multi-domain] Cd Length: 85 Bit Score: 68.60 E-value: 7.79e-14

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422    886 PDPPEIEIKDVKARTITLRWTMGFDGNSPITGYDIECKNKSDSWDSAQRTkdVSPQLNSATIIDIHPSSTYSIRMYAKNR 965
Cdd:pfam00041    1 SAPSNLTVTDVTSTSLTVSWTPPPDGNGPITGYEVEYRPKNSGEPWNEIT--VPGTTTSVTLTGLKPGTEYEVRVQAVNG 78


                   ....*..
gi 20127422    966 IGKSEPS 972
Cdd:pfam00041   79 GGEGPPS 85

Immunoglobulin domain; This family contains immunoglobulin-like domains.

Pssm-ID: 464046 [Multi-domain] Cd Length: 78 Bit Score: 67.21 E-value: 1.80e-13

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422    407 PKIISAFSEKVVSPAEPVSLMCNVKGTPLPTITWTLDDDPILKGgshriSQMITSEGNVVSYLNISSSQVRDGGVYRCTA 486
Cdd:pfam13927    2 PVITVSPSSVTVREGETVTLTCEATGSPPPTITWYKNGEPISSG-----STRSRSLSGSNSTLTISNVTRSDAGTYTCVA 76


                   ..
gi 20127422    487 NN 488
Cdd:pfam13927   77 SN 78

Immunoglobulin I-set domain;

Pssm-ID: 400151 [Multi-domain] Cd Length: 90 Bit Score: 67.67 E-value: 1.92e-13

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422    407 PKIISAFSEKVVSPAEPVSLMCNVKGTPLPTITWTLDDDPILKGGSHRisqmITSEGNVVSyLNISSSQVRDGGVYRCTA 486
Cdd:pfam07679    1 PKFTQKPKDVEVQEGESARFTCTVTGTPDPEVSWFKDGQPLRSSDRFK----VTYEGGTYT-LTISNVQPDDSGKYTCVA 75


                   ....*
gi 20127422    487 NNSAG 491
Cdd:pfam07679   76 TNSAG 80

Immunoglobulin I-set domain;

Pssm-ID: 400151 [Multi-domain] Cd Length: 90 Bit Score: 67.67 E-value: 1.92e-13

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422    596 PPFIQPfefPR---FSIGQRVFIPCVVvSGDLPITITWQKDGRPIPGSLGVTIDNIDFTSSLRISNLSLMHNGNYTCIAR 672
Cdd:pfam07679    1 PKFTQK---PKdveVQEGESARFTCTV-TGTPDPEVSWFKDGQPLRSSDRFKVTYEGGTYTLTISNVQPDDSGKYTCVAT 76

                           90
                   ....*....|....
gi 20127422    673 NEAAAVEHQSQLIV 686
Cdd:pfam07679   77 NSAGEAEASAELTV 90

Fibronectin type 3 domain; One of three types of internal repeats found in the plasma protein fibronectin. Its tenth fibronectin type III repeat contains an RGD cell recognition sequence in a flexible loop between 2 strands. Approximately 2% of all animal proteins contain the FN3 repeat; including extracellular and intracellular proteins, membrane spanning cytokine receptors, growth hormone receptors, tyrosine phosphatase receptors, and adhesion molecules. FN3-like domains are also found in bacterial glycosyl hydrolases.

Pssm-ID: 238020 [Multi-domain] Cd Length: 93 Bit Score: 67.91 E-value: 1.97e-13

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  986 GPPQEVHLEPISSQSIRVTWKAPKKHlqNGIIRGYQIGYREYSTGGNFQFNiisvDTSGDSEVYTLDNLNKFTQYGLVVQ 1065
Cdd:cd00063    2 SPPTNLRVTDVTSTSVTLSWTPPEDD--GGPITGYVVEYREKGSGDWKEVE----VTPGSETSYTLTGLKPGTEYEFRVR 75

                         90
                 ....*....|....*...
gi 20127422 1066 ACNRAGTGPSSQEIITTT 1083
Cdd:cd00063   76 AVNGGGESPPSESVTVTT 93

Immunoglobulin like; IG domains that cannot be classified into one of IGv1, IGc1, IGc2, IG.

Pssm-ID: 214653 [Multi-domain] Cd Length: 85 Bit Score: 67.53 E-value: 2.14e-13

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422     236 AMAGQRVELPCKALGHPEPDYRWLKDNM-PLELSGRFQ----KTVTGLLIENIRPSDSGSYVCEVSNRYGTAKVIGRLYV 310
Cdd:smart00410    6 VKEGESVTLSCEASGSPPPEVTWYKQGGkLLAESGRFSvsrsGSTSTLTISNVTPEDSGTYTCAATNSSGSASSGTTLTV 85

Immunoglobulin domain; This family contains immunoglobulin-like domains.

Pssm-ID: 464046 [Multi-domain] Cd Length: 78 Bit Score: 66.43 E-value: 3.50e-13

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 20127422   1287 RILTFSGTVTTPWMKDIVLPCKAVGDPSPAVKWMKDSNGTPSLVTIDGRRSiFSNGSFIIRTVKAEDSGYYSCIANN 1363
Cdd:pfam13927    3 VITVSPSSVTVREGETVTLTCEATGSPPPTITWYKNGEPISSGSTRSRSLS-GSNSTLTISNVTRSDAGTYTCVASN 78

Immunoglobulin domain; The members here are composed of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. Members of this group are components of immunoglobulin, neuroglia, cell surface glycoproteins, including T-cell receptors, CD2, CD4, CD8, and membrane glycoproteins, including butyrophilin and chondroitin sulfate proteoglycan core protein. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. Ig superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Typically, the V-set domains have A, B, E, and D strands in one sheet and A', G, F, C, C' and C" in the other. The structures in C1-set are smaller than those in the V-set; they have one beta sheet that is formed by strands A, B, E, and D and the other by strands G, F, C, and C'. Moreover, a C1-set Ig domain contains a short C' strand (three residues) and lacks A' and C" strand. Unlike other Ig domain sets, C2-set structures do not have a D strand. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409353 [Multi-domain] Cd Length: 70 Bit Score: 65.81 E-value: 4.95e-13

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 20127422  242 VELPCKALGHPEPDYRWLKDNMPLELSGRFQKTVTG----LLIENIRPSDSGSYVCEVSNRYGT 301
Cdd:cd00096    1 VTLTCSASGNPPPTITWYKNGKPLPPSSRDSRRSELgngtLTISNVTLEDSGTYTCVASNSAGG 64

Third immunoglobulin (Ig) domain of contactin-1; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-1. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-1 is differentially expressed in tumor tissues and may through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 143259 Cd Length: 88 Bit Score: 66.20 E-value: 5.39e-13

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  225 PSILDGFDHRKAMAGQRVELPCKALGHPEPDYRWLKDNMPLELSGRFQKTVTGLLIENIRPSDSGSYVCEVSNRYGTAKV 304
Cdd:cd05851    2 ADINVKFKDTYALKGQNVTLECFALGNPVPVIRWRKILEPMPATAEISMSGAVLKIFNIQPEDEGTYECEAENIKGKDKH 81


                 ....*..
gi 20127422  305 IGRLYVK 311
Cdd:cd05851   82 QARVYVQ 88

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor_like-1(FGFRL1); member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor like-1(FGFRL1). FGFRL1 is comprised of a signal peptide, three extracellular Ig-like modules, a transmembrane segment, and a short intracellular domain. FGFRL1 is expressed preferentially in skeletal tissues. Similar to FGF receptors, the expressed protein interacts specifically with heparin and with FGF2. FGFRL1 does not have a protein tyrosine kinase domain at its C-terminus; neither does its cytoplasmic domain appear to interact with a signaling partner. It has been suggested that FGFRL1 may not have any direct signaling function, but instead acts as a decoy receptor trapping FGFs and preventing them from binding other receptors.

Pssm-ID: 409442 Cd Length: 92 Bit Score: 66.42 E-value: 5.55e-13

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 20127422  239 GQRVELPCKALGHPEPDYRWLKDNMPL--ELSGRFQKTVTGLLIENIRPSDSGSYVCEVSNRYG 300
Cdd:cd05856   19 GSSVRLKCVASGNPRPDITWLKDNKPLtpPEIGENKKKKWTLSLKNLKPEDSGKYTCHVSNRAG 82

Third immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, and Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409390 [Multi-domain] Cd Length: 83 Bit Score: 66.26 E-value: 5.62e-13

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  696 PRDQDGIYGKAVILNCSAEGYPVPTIVWKFSKGAgvpqfQPIalnGRIQVLSNGSLLIKHVVEEDSGYYLCKVSNDVGAd 775
Cdd:cd05725    4 PQNQVVLVDDSAEFQCEVGGDPVPTVRWRKEDGE-----LPK---GRYEILDDHSLKIRKVTAGDMGSYTCVAENMVGK- 74


                 ....*....
gi 20127422  776 VSKSMYLTV 784
Cdd:cd05725   75 IEASATLTV 83

Immunoglobulin domain; The members here are composed of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. Members of this group are components of immunoglobulin, neuroglia, cell surface glycoproteins, including T-cell receptors, CD2, CD4, CD8, and membrane glycoproteins, including butyrophilin and chondroitin sulfate proteoglycan core protein. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. Ig superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Typically, the V-set domains have A, B, E, and D strands in one sheet and A', G, F, C, C' and C" in the other. The structures in C1-set are smaller than those in the V-set; they have one beta sheet that is formed by strands A, B, E, and D and the other by strands G, F, C, and C'. Moreover, a C1-set Ig domain contains a short C' strand (three residues) and lacks A' and C" strand. Unlike other Ig domain sets, C2-set structures do not have a D strand. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409353 [Multi-domain] Cd Length: 70 Bit Score: 65.81 E-value: 5.95e-13

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  613 VFIPCVVvSGDLPITITWQKDGRPIPGSLGVTIDNIDFTSSLRISNLSLMHNGNYTCIARNEAAAVEHQS 682
Cdd:cd00096    1 VTLTCSA-SGNPPPTITWYKNGKPLPPSSRDSRRSELGNGTLTISNVTLEDSGTYTCVASNSAGGSASAS 69

Second immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. DSCAM is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409545 Cd Length: 95 Bit Score: 66.03 E-value: 7.76e-13

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  689 PPKFVVQPRDQDGIYGKAVILN--CSAEGYPVPTIVW-KFSKGAgvPQFQPIALNGRIQVLSnGSLLIKHVVEEDSGYYL 765
Cdd:cd20953    1 APKIPGLSKSQPLTVSSASSIAllCPAQGYPAPSFRWyKFIEGT--TRKQAVVLNDRVKQVS-GTLIIKDAVVEDSGKYL 77

                         90
                 ....*....|....*....
gi 20127422  766 CKVSNDVGADvSKSMYLTV 784
Cdd:cd20953   78 CVVNNSVGGE-SVETVLTV 95

agrin-responsive first immunoglobulin-like domains (Ig1) of the MuSK ectodomain; a member of the I-set of IgSF domains; The members here are composed of the first immunoglobulin-like domains (Ig1) of the Muscle-specific kinase (MuSK). MuSK is a receptor tyrosine kinase specifically expressed in skeletal muscle, where it plays a central role in the formation and maintenance of the neuromuscular junction (NMJ). MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. The activation of MUSK in myotubes regulates the formation of NMJs through the regulation of different processes including the specific expression of genes in subsynaptic nuclei, the reorganization of the actin cytoskeleton and the clustering of the acetylcholine receptors (AChR) in the postsynaptic membrane. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the MuSK lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409562 [Multi-domain] Cd Length: 92 Bit Score: 65.99 E-value: 8.21e-13

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  695 QPRDQDGIYGKAVILNCSAEGYPVPTIVWKFSKGagvpqfQPIALNGRIQVLSNGSLL-IKHVVEEDSGYYLCKVSNDVG 773
Cdd:cd20970    8 PSFTVTAREGENATFMCRAEGSPEPEISWTRNGN------LIIEFNTRYIVRENGTTLtIRNIRRSDMGIYLCIASNGVP 81

                         90
                 ....*....|.
gi 20127422  774 ADVSKSMYLTV 784
Cdd:cd20970   82 GSVEKRITLQV 92

Fifth Ig-like domain of Roundabout (Robo) homolog 1/2, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fifth Ig-like domain of Roundabout (Robo) homolog 1/2 and similar domains. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, -2, and -3), and three mammalian Slit homologs (Slit-1,-2, -3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, -2, and -3 are expressed by commissural neurons in the vertebrate spinal cord and Slits 1, -2, -3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of slit responsiveness, antagonizes slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be is the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. The fifth Ig-like domain of Robo 1 and 2 is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors

Pssm-ID: 409544 [Multi-domain] Cd Length: 87 Bit Score: 65.60 E-value: 8.48e-13

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  692 FVVQPRDQDGIYGKAVILNCSAEGYPVPTIVWkfSKGAgvpqFQPIALNGRIQVLSNGSLLIKHVVEEDSGYYLCKVSND 771
Cdd:cd20952    2 ILQGPQNQTVAVGGTVVLNCQATGEPVPTISW--LKDG----VPLLGKDERITTLENGSLQIKGAEKSDTGEYTCVALNL 75

                         90
                 ....*....|...
gi 20127422  772 VGaDVSKSMYLTV 784
Cdd:cd20952   76 SG-EATWSAVLDV 87

Immunoglobulin like; IG domains that cannot be classified into one of IGv1, IGc1, IGc2, IG.

Pssm-ID: 214653 [Multi-domain] Cd Length: 85 Bit Score: 64.45 E-value: 2.03e-12

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422     608 SIGQRVFIPCVVvSGDLPITITWQKDG-RPIPGSLGVTIDNIDFTSSLRISNLSLMHNGNYTCIARNEAAAVEHQSQLIV 686
Cdd:smart00410    7 KEGESVTLSCEA-SGSPPPEVTWYKQGgKLLAESGRFSVSRSGSTSTLTISNVTPEDSGTYTCAATNSSGSASSGTTLTV 85

Third immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the Constant 2 (C2)-set of IgSF domains; The members here are composed of the third immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. This group belongs to the C2-set of IgSF domains, having A, B, and E strands in one beta-sheet and A', G, F, C, and C' in the other. Unlike other Ig domain sets, the C2-set lacks the D strand.

Pssm-ID: 409549 [Multi-domain] Cd Length: 88 Bit Score: 64.48 E-value: 2.44e-12

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  313 PLKATISPRKVKSSVGSQVSLSCSVTGTEDQELSWYRNGEILnpGKNVRITGINHENLIMDHMVKSDGGAYQCFVRKDKL 392
Cdd:cd20957    1 PLSATIDPPVQTVDFGRTAVFNCSVTGNPIHTVLWMKDGKPL--GHSSRVQILSEDVLVIPSVKREDKGMYQCFVRNDGD 78


                 ...
gi 20127422  393 SAQ 395
Cdd:cd20957   79 SAQ 81

Immunoglobulin (Ig)-like I-set domain of Neural Cell Adhesion Molecule 1 (NCAM-1) and similar proteins; The members here are composed of the fourth immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule (NCAM-1). NCAM plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM), and heterophilic (NCAM-non-NCAM), interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves Ig1, Ig2, and Ig3. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions), through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain. Also included in this group is NCAM-2 (also known as OCAM/mamFas II and RNCAM) NCAM-2 is differentially expressed in the developing and mature olfactory epithelium (OE). One of the unique features of I-set domains is the lack of a C" strand. The structures of this group show that the Ig domain lacks this strand and thus is a member of the I-set of Ig domains.

Pssm-ID: 409395 [Multi-domain] Cd Length: 96 Bit Score: 64.85 E-value: 2.50e-12

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  688 VPPKfVVQPRDQDGIYGKAVILNCSAEGYPVPTIVWKFSkgAGVPQFQPIALNGRIQVLSN---GSLLIKHVVEEDSGYY 764
Cdd:cd05732    1 VQPK-ITYLENQTAVELEQITLTCEAEGDPIPEITWRRA--TRGISFEEGDLDGRIVVRGHarvSSLTLKDVQLTDAGRY 77

                         90       100
                 ....*....|....*....|
gi 20127422  765 LCKVSNDVGADvSKSMYLTV 784
Cdd:cd05732   78 DCEASNRIGGD-QQSMYLEV 96

Fourth Ig-like domain from smooth muscle myosin light chain kinase and similar domains ; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain from smooth muscle myosin light chain kinase (MYLK) and similar domains. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of this group shows that the fourth Ig-like domain from myosin light chain kinase lacks this strand and thus belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409568 [Multi-domain] Cd Length: 90 Bit Score: 64.19 E-value: 2.86e-12

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  407 PKIISAFSEKVVSPAEPVSLMCNVKGTPLPTITWTLDDDPILKGGSHRISQMITSEgnvvsyLNISSSQVRDGGVYRCTA 486
Cdd:cd20976    2 PSFSSVPKDLEAVEGQDFVAQCSARGKPVPRITWIRNAQPLQYAADRSTCEAGVGE------LHIQDVLPEDHGTYTCLA 75

                         90
                 ....*....|....*
gi 20127422  487 NNSAGVVLYQARINV 501
Cdd:cd20976   76 KNAAGQVSCSAWVTV 90

Immunoglobulin domain; The members here are composed of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. Members of this group are components of immunoglobulin, neuroglia, cell surface glycoproteins, including T-cell receptors, CD2, CD4, CD8, and membrane glycoproteins, including butyrophilin and chondroitin sulfate proteoglycan core protein. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. Ig superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Typically, the V-set domains have A, B, E, and D strands in one sheet and A', G, F, C, C' and C" in the other. The structures in C1-set are smaller than those in the V-set; they have one beta sheet that is formed by strands A, B, E, and D and the other by strands G, F, C, and C'. Moreover, a C1-set Ig domain contains a short C' strand (three residues) and lacks A' and C" strand. Unlike other Ig domain sets, C2-set structures do not have a D strand. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409353 [Multi-domain] Cd Length: 70 Bit Score: 63.50 E-value: 3.81e-12

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 20127422 1303 IVLPCKAVGDPSPAVKWMKDsNGTPSLVTIDGRRSIFSNGSFIIRTVKAEDSGYYSCIANNNWG 1366
Cdd:cd00096    1 VTLTCSASGNPPPTITWYKN-GKPLPPSSRDSRRSELGNGTLTISNVTLEDSGTYTCVASNSAG 63

Immunoglobulin domain; The members here are composed of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. Members of this group are components of immunoglobulin, neuroglia, cell surface glycoproteins, including T-cell receptors, CD2, CD4, CD8, and membrane glycoproteins, including butyrophilin and chondroitin sulfate proteoglycan core protein. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. Ig superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Typically, the V-set domains have A, B, E, and D strands in one sheet and A', G, F, C, C' and C" in the other. The structures in C1-set are smaller than those in the V-set; they have one beta sheet that is formed by strands A, B, E, and D and the other by strands G, F, C, and C'. Moreover, a C1-set Ig domain contains a short C' strand (three residues) and lacks A' and C" strand. Unlike other Ig domain sets, C2-set structures do not have a D strand. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409353 [Multi-domain] Cd Length: 70 Bit Score: 63.50 E-value: 3.81e-12

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 20127422  707 VILNCSAEGYPVPTIVWKFSKGagvpQFQPIALNGRIQVLSNGSLLIKHVVEEDSGYYLCKVSNDVGADVSKS 779
Cdd:cd00096    1 VTLTCSASGNPPPTITWYKNGK----PLPPSSRDSRRSELGNGTLTISNVTLEDSGTYTCVASNSAGGSASAS 69

Immunoglobulin like; IG domains that cannot be classified into one of IGv1, IGc1, IGc2, IG.

Pssm-ID: 214653 [Multi-domain] Cd Length: 85 Bit Score: 63.68 E-value: 3.95e-12

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422     704 GKAVILNCSAEGYPVPTIVWKFSKGagvpqfQPIALNGRIQVLSNG---SLLIKHVVEEDSGYYLCKVSNDVGaDVSKSM 780
Cdd:smart00410    9 GESVTLSCEASGSPPPEVTWYKQGG------KLLAESGRFSVSRSGstsTLTISNVTPEDSGTYTCAATNSSG-SASSGT 81


                    ....
gi 20127422     781 YLTV 784
Cdd:smart00410   82 TLTV 85

Fourth immunoglobulin (Ig)-like domain of hemolin, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain of hemolin and similar proteins. Hemolin, an insect immunoglobulin superfamily (IgSF) member containing four Ig-like domains, is a lipopolysaccharide-binding immune protein induced during bacterial infection. Hemolin shares significant sequence similarity with the first four Ig-like domains of the transmembrane cell adhesion molecules (CAMs) of the L1 family. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The fourth Ig-like domain of hemolin is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409570 [Multi-domain] Cd Length: 88 Bit Score: 63.57 E-value: 5.81e-12

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 20127422  225 PSILDGFDHRKAM-AGQRVELPCKALGHPEPDYRWLKDNMPL-ELSGRFQKTVTGLLIENIRPSDSGSYVCEVSNRYGT 301
Cdd:cd20978    1 PKFIQKPEKNVVVkGGQDVTLPCQVTGVPQPKITWLHNGKPLqGPMERATVEDGTLTIINVQPEDTGYYGCVATNEIGD 79

Immunoglobulin domain; This family contains immunoglobulin-like domains.

Pssm-ID: 464046 [Multi-domain] Cd Length: 78 Bit Score: 62.97 E-value: 7.13e-12

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 20127422    225 PSILDGFDHRKAMAGQRVELPCKALGHPEPDYRWLKDNMPL-ELSGRFQKTVTG---LLIENIRPSDSGSYVCEVSN 297
Cdd:pfam13927    2 PVITVSPSSVTVREGETVTLTCEATGSPPPTITWYKNGEPIsSGSTRSRSLSGSnstLTISNVTRSDAGTYTCVASN 78

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor, and similar domains; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor. FGF receptors bind FGF signaling polypeptides. FGFs participate in multiple processes such as morphogenesis, development, and angiogenesis. FGFs bind to four FGF receptor tyrosine kinases (FGFR1, FGFR2, FGFR3, FGFR4). Receptor diversity is controlled by alternative splicing producing splice variants with different ligand binding characteristics and different expression patterns. FGFRs have an extracellular region comprised of three Ig-like domains, a single transmembrane helix, and an intracellular tyrosine kinase domain. Ligand binding and specificity reside in the Ig-like domains 2 and 3, and the linker region that connects these two. FGFR activation and signaling depend on FGF-induced dimerization, a process involving cell surface heparin or heparin sulfate proteoglycans. This group also contains fibroblast growth factor (FGF) receptor like-1(FGFRL1). FGFRL1 does not have a protein tyrosine kinase domain at its C-terminus; neither does its cytoplasmic domain appear to interact with a signaling partner. It has been suggested that FGFRL1 may not have any direct signaling function, but instead acts as a decoy receptor trapping FGFs and preventing them from binding other receptors.

Pssm-ID: 409393 [Multi-domain] Cd Length: 95 Bit Score: 63.01 E-value: 9.53e-12

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 20127422  238 AGQRVELPCKALGHPEPDYRWLKDNMPLELS-----GRFQKTVTGLLIENIRPSDSGSYVCEVSNRYGT 301
Cdd:cd05729   18 AANKVRLECGAGGNPMPNITWLKDGKEFKKEhriggTKVEEKGWSLIIERAIPRDKGKYTCIVENEYGS 86

Immunoglobulin domain; This family contains immunoglobulin-like domains.

Pssm-ID: 464046 [Multi-domain] Cd Length: 78 Bit Score: 62.20 E-value: 1.03e-11

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 20127422    610 GQRVFIPCVVVSGDLPiTITWQKDGRPIPGSLGVTIDNIDFTSSLRISNLSLMHNGNYTCIARN 673
Cdd:pfam13927   16 GETVTLTCEATGSPPP-TITWYKNGEPISSGSTRSRSLSGSNSTLTISNVTRSDAGTYTCVASN 78

Fibronectin type 3 domain; One of three types of internal repeat within the plasma protein, fibronectin. The tenth fibronectin type III repeat contains a RGD cell recognition sequence in a flexible loop between 2 strands. Type III modules are present in both extracellular and intracellular proteins.

Pssm-ID: 214495 [Multi-domain] Cd Length: 83 Bit Score: 62.63 E-value: 1.09e-11

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422     986 GPPQEVHLEPISSQSIRVTWKAPKKHLQNGIIRGYQIGYREYSTggnfqfNIISVDTSGDSEVYTLDNLNKFTQYGLVVQ 1065
Cdd:smart00060    2 SPPSNLRVTDVTSTSVTLSWEPPPDDGITGYIVGYRVEYREEGS------EWKEVNVTPSSTSYTLTGLKPGTEYEFRVR 75


                    ....*...
gi 20127422    1066 ACNRAGTG 1073
Cdd:smart00060   76 AVNGAGEG 83

Fifth immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fifth immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409550 [Multi-domain] Cd Length: 89 Bit Score: 62.58 E-value: 1.17e-11

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  704 GKAVILNCSAEGYPVPTIVWKfsKGAgvpqfQPIALNGRIQVLSNGSLLIKHVV-EEDSGYYLCKVSNDVGADVSKSMYL 782
Cdd:cd20958   15 GQTLRLHCPVAGYPISSITWE--KDG-----RRLPLNHRQRVFPNGTLVIENVQrSSDEGEYTCTARNQQGQSASRSVFV 87


                 ..
gi 20127422  783 TV 784
Cdd:cd20958   88 KV 89

Fibronectin type 3 domain; One of three types of internal repeats found in the plasma protein fibronectin. Its tenth fibronectin type III repeat contains an RGD cell recognition sequence in a flexible loop between 2 strands. Approximately 2% of all animal proteins contain the FN3 repeat; including extracellular and intracellular proteins, membrane spanning cytokine receptors, growth hormone receptors, tyrosine phosphatase receptors, and adhesion molecules. FN3-like domains are also found in bacterial glycosyl hydrolases.

Pssm-ID: 238020 [Multi-domain] Cd Length: 93 Bit Score: 62.51 E-value: 1.20e-11

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1091 PPENVQAIATSPESISISWSTLSKEalNGILQGFRVIYWaNLMDGELGEIKNITTTQPSLELDGLEKYTNYSIQVLAFTR 1170
Cdd:cd00063    3 PPTNLRVTDVTSTSVTLSWTPPEDD--GGPITGYVVEYR-EKGSGDWKEVEVTPGSETSYTLTGLKPGTEYEFRVRAVNG 79

                         90
                 ....*....|....
gi 20127422 1171 AGDGVRSEQIFTRT 1184
Cdd:cd00063   80 GGESPPSESVTVTT 93

Immunoglobulin like; IG domains that cannot be classified into one of IGv1, IGc1, IGc2, IG.

Pssm-ID: 214653 [Multi-domain] Cd Length: 85 Bit Score: 62.14 E-value: 1.28e-11

                            10        20        30        40        50        60        70
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 20127422    1302 DIVLPCKAVGDPSPAVKWMKDSngtPSLVTIDGRRSIFSNG---SFIIRTVKAEDSGYYSCIANNNWGSDEIILNLQV 1376
Cdd:smart00410   11 SVTLSCEASGSPPPEVTWYKQG---GKLLAESGRFSVSRSGstsTLTISNVTPEDSGTYTCAATNSSGSASSGTTLTV 85

Fourth immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409548 [Multi-domain] Cd Length: 96 Bit Score: 62.58 E-value: 1.32e-11

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  610 GQRVFIPCVVVSGDLPiTITWQKDGRPIPGSLG------VTIDNiDFTSSLRISNLSLMHNGNYTCIARNEAAAVEHQSQ 683
Cdd:cd20956   16 GPSVSLKCVASGNPLP-QITWTLDGFPIPESPRfrvgdyVTSDG-DVVSYVNISSVRVEDGGEYTCTATNDVGSVSHSAR 93


                 ...
gi 20127422  684 LIV 686
Cdd:cd20956   94 INV 96

Fibronectin type III domain;

Pssm-ID: 394996 [Multi-domain] Cd Length: 85 Bit Score: 62.05 E-value: 1.55e-11

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422   1091 PPENVQAIATSPESISISWSTLskEALNGILQGFRVIYWanlMDGELGEIKNITT--TQPSLELDGLEKYTNYSIQVLAF 1168
Cdd:pfam00041    2 APSNLTVTDVTSTSLTVSWTPP--PDGNGPITGYEVEYR---PKNSGEPWNEITVpgTTTSVTLTGLKPGTEYEVRVQAV 76


                   ....*....
gi 20127422   1169 TRAGDGVRS 1177
Cdd:pfam00041   77 NGGGEGPPS 85

Fibronectin type III domain;

Pssm-ID: 394996 [Multi-domain] Cd Length: 85 Bit Score: 62.05 E-value: 1.57e-11

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422    986 GPPQEVHLEPISSQSIRVTWKAPKKHlqNGIIRGYQIGYREYSTGGNFQfniiSVDTSGDSEVYTLDNLNKFTQYGLVVQ 1065
Cdd:pfam00041    1 SAPSNLTVTDVTSTSLTVSWTPPPDG--NGPITGYEVEYRPKNSGEPWN----EITVPGTTTSVTLTGLKPGTEYEVRVQ 74

                           90
                   ....*....|.
gi 20127422   1066 ACNRAGTGPSS 1076
Cdd:pfam00041   75 AVNGGGEGPPS 85

Fourth immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; Members here are composed the fourth immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, Robo3), and three mammalian Slit homologs (Slit-1, Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, and Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409391 [Multi-domain] Cd Length: 98 Bit Score: 62.28 E-value: 1.78e-11

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  691 KFVVQPRDQDGIYGKAVILNCSAEGYPVPTIVWKfSKGAGVPQF--QPIALNGRIQVLSNGSLLIKHVVEEDSGYYLCKV 768
Cdd:cd05726    1 QFVVKPRDQVVALGRTVTFQCETKGNPQPAIFWQ-KEGSQNLLFpyQPPQPSSRFSVSPTGDLTITNVQRSDVGYYICQA 79

                         90
                 ....*....|....*..
gi 20127422  769 SNDVGADVSKSmYLTVK 785
Cdd:cd05726   80 LNVAGSILAKA-QLEVT 95

Fourth immunoglobulin (Ig)-like domain of hemolin, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain of hemolin and similar proteins. Hemolin, an insect immunoglobulin superfamily (IgSF) member containing four Ig-like domains, is a lipopolysaccharide-binding immune protein induced during bacterial infection. Hemolin shares significant sequence similarity with the first four Ig-like domains of the transmembrane cell adhesion molecules (CAMs) of the L1 family. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The fourth Ig-like domain of hemolin is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409570 [Multi-domain] Cd Length: 88 Bit Score: 61.64 E-value: 2.13e-11

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 20127422 1302 DIVLPCKAVGDPSPAVKWMKdsNGTPslvtIDGR--RSIFSNGSFIIRTVKAEDSGYYSCIANNNWGSDEIILNLQV 1376
Cdd:cd20978   18 DVTLPCQVTGVPQPKITWLH--NGKP----LQGPmeRATVEDGTLTIINVQPEDTGYYGCVATNEIGDIYTETLLHV 88

Fibronectin type 3 domain; One of three types of internal repeats found in the plasma protein fibronectin. Its tenth fibronectin type III repeat contains an RGD cell recognition sequence in a flexible loop between 2 strands. Approximately 2% of all animal proteins contain the FN3 repeat; including extracellular and intracellular proteins, membrane spanning cytokine receptors, growth hormone receptors, tyrosine phosphatase receptors, and adhesion molecules. FN3-like domains are also found in bacterial glycosyl hydrolases.

Pssm-ID: 238020 [Multi-domain] Cd Length: 93 Bit Score: 61.74 E-value: 2.36e-11

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1189 PGPPAGVKAAAASASMVFVSWLPPLKLNGIIRKYTVFCSHPYPTVISEFE-ASPDSFSYRIPNLSRNRQYSVWVVAVTSA 1267
Cdd:cd00063    1 PSPPTNLRVTDVTSTSVTLSWTPPEDDGGPITGYVVEYREKGSGDWKEVEvTPGSETSYTLTGLKPGTEYEFRVRAVNGG 80

                         90
                 ....*....|.
gi 20127422 1268 GRGNSSEIITV 1278
Cdd:cd00063   81 GESPPSESVTV 91

Immunoglobulin (Ig)-like domain of myotilin, palladin, and myopalladin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the immunoglobulin (Ig)-like domain in myotilin, palladin, and myopalladin. Myotilin, palladin, and myopalladin function as scaffolds that regulate actin organization. Myotilin and myopalladin are most abundant in skeletal and cardiac muscle; palladin is ubiquitously expressed in the organs of developing vertebrates and plays a key role in cellular morphogenesis. The three family members each interact with specific molecular partners with all three binding to alpha-actinin; In addition, palladin also binds to vasodilator-stimulated phosphoprotein (VASP) and ezrin, myotilin binds to filamin and actin, and myopalladin also binds to nebulin and cardiac ankyrin repeat protein (CARP). This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409405 [Multi-domain] Cd Length: 91 Bit Score: 61.74 E-value: 2.46e-11

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  407 PKIISAFSEKVVSPAEPVSLMCNVKGTPLPTITWTLDDDPILKGGSHRisqMITSEGNVVSyLNISSSQVRDGGVYRCTA 486
Cdd:cd05744    1 PHFLQAPGDLEVQEGRLCRFDCKVSGLPTPDLFWQLNGKPVRPDSAHK---MLVRENGRHS-LIIEPVTKRDAGIYTCIA 76

                         90
                 ....*....|....*
gi 20127422  487 NNSAGVVLYQARINV 501
Cdd:cd05744   77 RNRAGENSFNAELVV 91

Immunoglobulin domain; The members here are composed of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. Members of this group are components of immunoglobulin, neuroglia, cell surface glycoproteins, including T-cell receptors, CD2, CD4, CD8, and membrane glycoproteins, including butyrophilin and chondroitin sulfate proteoglycan core protein. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. Ig superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Typically, the V-set domains have A, B, E, and D strands in one sheet and A', G, F, C, C' and C" in the other. The structures in C1-set are smaller than those in the V-set; they have one beta sheet that is formed by strands A, B, E, and D and the other by strands G, F, C, and C'. Moreover, a C1-set Ig domain contains a short C' strand (three residues) and lacks A' and C" strand. Unlike other Ig domain sets, C2-set structures do not have a D strand. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409353 [Multi-domain] Cd Length: 70 Bit Score: 60.42 E-value: 3.71e-11

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 20127422  424 VSLMCNVKGTPLPTITWTLDDDPILKGGSHRIsqmitSEGNVVSYLNISSSQVRDGGVYRCTANNSAG 491
Cdd:cd00096    1 VTLTCSASGNPPPTITWYKNGKPLPPSSRDSR-----RSELGNGTLTISNVTLEDSGTYTCVASNSAG 63

Immunoglobulin I-set domain;

Pssm-ID: 400151 [Multi-domain] Cd Length: 90 Bit Score: 61.12 E-value: 4.05e-11

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 20127422   1301 KDIVLPCKAVGDPSPAVKWMKDsnGTPslVTIDGRRSIFSNG---SFIIRTVKAEDSGYYSCIANNNWGSDEIILNLQV 1376
Cdd:pfam07679   16 ESARFTCTVTGTPDPEVSWFKD--GQP--LRSSDRFKVTYEGgtyTLTISNVQPDDSGKYTCVATNSAGEAEASAELTV 90

Immunoglobulin I-set domain of the Leucine-rich repeat and immunoglobin-like domain-containing protein 1 (Lingo-1); The members here are composed of the immunoglobulin I-set (IgI) domain of the Leucine-rich repeat and immunoglobin-like domain-containing protein 1 (Lingo-1). Human Lingo-1 is a central nervous system-specific transmembrane glycoprotein also known as LERN-1, which functions as a negative regulator of neuronal survival, axonal regeneration, and oligodendrocyte differentiation and myelination. Lingo-1 is a key component of the Nogo receptor signaling complex (RTN4R/NGFR) in RhoA activation responsible for some inhibition of axonal regeneration by myelin-associated factors. The ligand-binding ectodomain of human Lingo-1 contains a bimodular, kinked structure composed of leucine-rich repeat (LRR) and immunoglobulin (Ig)-like modules. Diseases associated with Lingo-1 include mental retardation, autosomal recessive 64 and essential tremor. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the Lingo-1 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409561 Cd Length: 92 Bit Score: 60.87 E-value: 4.97e-11

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 20127422 1301 KDIVLPCKAVGDPSPAVKWMkdSNGT-PSLVTIDGRRSIFSNGSFIIRTVKAEDSGYYSCIANNNWGSDEIILNLQV 1376
Cdd:cd20969   18 HTVQFVCRADGDPPPAILWL--SPRKhLVSAKSNGRLTVFPDGTLEVRYAQVQDNGTYLCIAANAGGNDSMPAHLHV 92

Fifth Ig-like domain of Roundabout (Robo) homolog 1/2, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fifth Ig-like domain of Roundabout (Robo) homolog 1/2 and similar domains. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, -2, and -3), and three mammalian Slit homologs (Slit-1,-2, -3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, -2, and -3 are expressed by commissural neurons in the vertebrate spinal cord and Slits 1, -2, -3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of slit responsiveness, antagonizes slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be is the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. The fifth Ig-like domain of Robo 1 and 2 is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors

Pssm-ID: 409544 [Multi-domain] Cd Length: 87 Bit Score: 60.20 E-value: 7.83e-11

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 20127422 1302 DIVLPCKAVGDPSPAVKWMKDSNgtpSLVTIDGRRSIFSNGSFIIRTVKAEDSGYYSCIANNNWGS 1367
Cdd:cd20952   16 TVVLNCQATGEPVPTISWLKDGV---PLLGKDERITTLENGSLQIKGAEKSDTGEYTCVALNLSGE 78

Second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of the Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit-2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409389 [Multi-domain] Cd Length: 87 Bit Score: 60.11 E-value: 9.23e-11

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 20127422  236 AMAGQRVELPCKA-LGHPEPDYRWLKDNMPLELSGRFQKTVTG--LLIENIRPSDSGSYVCEVSNRYGT 301
Cdd:cd05724    9 VAVGEMAVLECSPpRGHPEPTVSWRKDGQPLNLDNERVRIVDDgnLLIAEARKSDEGTYKCVATNMVGE 77

Immunoglobulin like; IG domains that cannot be classified into one of IGv1, IGc1, IGc2, IG.

Pssm-ID: 214653 [Multi-domain] Cd Length: 85 Bit Score: 59.44 E-value: 1.49e-10

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422     794 PNTTLATQGQKKEMSCTAHGEKPIIVRWEKEDRIINPEMARYLVStkevGEEVISTLQILPTVREDSGFFSCHAINSYGE 873
Cdd:smart00410    1 PPSVTVKEGESVTLSCEASGSPPPEVTWYKQGGKLLAESGRFSVS----RSGSTSTLTISNVTPEDSGTYTCAATNSSGS 76


                    ....*....
gi 20127422     874 DRGIIQLTV 882
Cdd:smart00410   77 ASSGTTLTV 85

Second Ig-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the titin Z1z2 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409564 [Multi-domain] Cd Length: 91 Bit Score: 59.13 E-value: 1.81e-10

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  689 PPKFVVQPRDQDGIYGKAVILNCSAEGYPVPTIVWkFSKGAGVpQFQPialngRIQVLSNG---SLLIKHVVEEDSGYYL 765
Cdd:cd20972    1 PPQFIQKLRSQEVAEGSKVRLECRVTGNPTPVVRW-FCEGKEL-QNSP-----DIQIHQEGdlhSLIIAEAFEEDTGRYS 73

                         90
                 ....*....|..
gi 20127422  766 CKVSNDVGADVS 777
Cdd:cd20972   74 CLATNSVGSDTT 85

Immunoglobulin like; IG domains that cannot be classified into one of IGv1, IGc1, IGc2, IG.

Pssm-ID: 214653 [Multi-domain] Cd Length: 85 Bit Score: 59.06 E-value: 1.99e-10

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422     417 VVSPAEPVSLMCNVKGTPLPTITWtLDDDPILKGGSHRISqmITSEGNVvSYLNISSSQVRDGGVYRCTANNSAGVVLYQ 496
Cdd:smart00410    5 TVKEGESVTLSCEASGSPPPEVTW-YKQGGKLLAESGRFS--VSRSGST-STLTISNVTPEDSGTYTCAATNSSGSASSG 80


                    ....*
gi 20127422     497 ARINV 501
Cdd:smart00410   81 TTLTV 85

Fourth Ig domain of the neural cell adhesion molecule contactin-2, and similar domains; The members here are composed of the fourth Ig domain of the neural cell adhesion molecule contactin-2. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-2 (also called TAG-1, axonin-1) facilitates cell adhesion by homophilic binding between molecules in apposed membranes. The first four Ig domains form the intermolecular binding fragment which arranges as a compact U-shaped module by contacts between Ig domains 1 and 4, and domains 2 and 3. It has been proposed that a linear zipper-like array forms, from contactin-2 molecules alternatively provided by the two apposed membranes.

Pssm-ID: 143205 [Multi-domain] Cd Length: 85 Bit Score: 58.77 E-value: 2.18e-10

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*.
gi 20127422  246 CKALGHPEPDYRWLKDNMPLELSGRFQKTVTGLLIENIRPSDSGSYVCEVSNRYGT 301
Cdd:cd05728   21 CKASGNPRPAYRWLKNGQPLASENRIEVEAGDLRITKLSLSDSGMYQCVAENKHGT 76

Immunoglobulin (Ig)-like domain of Down Syndrome Cell Adhesion molecule (DSCAM); The members here are composed of the immunoglobulin (Ig)-like domain of Down Syndrome Cell Adhesion molecule (DSCAM). DSCAM is a cell adhesion molecule expressed largely in the developing nervous system. The gene encoding DSCAM is located at human chromosome 21q22, the locus associated with the intellectual disability phenotype of Down Syndrome. DSCAM is predicted to be the largest member of the IG superfamily. It has been demonstrated that DSCAM can mediate cation-independent homophilic intercellular adhesion.

Pssm-ID: 409397 [Multi-domain] Cd Length: 97 Bit Score: 58.66 E-value: 3.05e-10

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 20127422 1301 KDIVLPCKAVGDPSPAVKWmKDSNGT-----PSLVTIDGRRSIFSNGSFIIRTVKAEDSGYYSCIANNNWGSD 1368
Cdd:cd05734   17 KAVVLNCSADGYPPPTIVW-KHSKGSgvpqfQHIVPLNGRIQLLSNGSLLIKHVLEEDSGYYLCKVSNDVGAD 88

Third immunoglobulin-like domain of the human WFIKKN (WAP, follistatin, immunoglobulin, Kunitz and NTR domain-containing protein), and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin-like domain of the human WFIKKN (WAP, follistatin, immunoglobulin, Kunitz and NTR domain-containing protein) and similar proteins. WFIKKN is a secreted protein that consists of multiple types of protease inhibitory modules, including two tandem Kunitz-type protease inhibitor-domains. The Ig superfamily is a heterogenous group of proteins built on a common fold comprised of a sandwich of two beta sheets. Members of the Ig superfamily are components of immunoglobulin, neuroglia, cell surface glycoproteins, such as T-cell receptors, CD2, CD4, CD8, and membrane glycoproteins, such as butyrophilin and chondroitin sulfate proteoglycan core protein. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409422 [Multi-domain] Cd Length: 95 Bit Score: 58.71 E-value: 3.18e-10

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  407 PKIISAFSEKVVSPAEPVSLMCNVKGTPLPTITWT--LDDDP--ILKGGSHRISQMITSEGNVVSYlnisSSQVRDGGVY 482
Cdd:cd05765    1 PALVNSPTHQTVKVGETASFHCDVTGRPQPEITWEkqVPGKEnlIMRPNHVRGNVVVTNIGQLVIY----NAQPQDAGLY 76

                         90
                 ....*....|.
gi 20127422  483 RCTANNSAGVV 493
Cdd:cd05765   77 TCTARNSGGLL 87

Fourth immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409548 [Multi-domain] Cd Length: 96 Bit Score: 58.34 E-value: 4.28e-10

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  224 APSILDGFDHRKAMAGQRVELPCKALGHPEPDYRWLKDNMPLELSGRFQ--------KTVTGLL-IENIRPSDSGSYVCE 294
Cdd:cd20956    1 APVLLETFSEQTLQPGPSVSLKCVASGNPLPQITWTLDGFPIPESPRFRvgdyvtsdGDVVSYVnISSVRVEDGGEYTCT 80

                         90
                 ....*....|....*.
gi 20127422  295 VSNRYGTAKVIGRLYV 310
Cdd:cd20956   81 ATNDVGSVSHSARINV 96

Fibronectin type 3 domain; One of three types of internal repeat within the plasma protein, fibronectin. The tenth fibronectin type III repeat contains a RGD cell recognition sequence in a flexible loop between 2 strands. Type III modules are present in both extracellular and intracellular proteins.

Pssm-ID: 214495 [Multi-domain] Cd Length: 83 Bit Score: 58.01 E-value: 4.60e-10

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422     885 PPDPPEIEIKDVKARTITLRWTMGFDGN--SPITGYDIECKNKSDSWdsaqRTKDVSPQLNSATIIDIHPSSTYSIRMYA 962
Cdd:smart00060    1 PSPPSNLRVTDVTSTSVTLSWEPPPDDGitGYIVGYRVEYREEGSEW----KEVNVTPSSTSYTLTGLKPGTEYEFRVRA 76


                    ....*..
gi 20127422     963 KNRIGKS 969
Cdd:smart00060   77 VNGAGEG 83

Third immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, and Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409390 [Multi-domain] Cd Length: 83 Bit Score: 57.79 E-value: 5.15e-10

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  236 AMAGQRVELPCKALGHPEPDYRWLKD--NMPLelsGRFQ----KTvtgLLIENIRPSDSGSYVCEVSNRYGTAKVIGRLY 309
Cdd:cd05725    9 VLVDDSAEFQCEVGGDPVPTVRWRKEdgELPK---GRYEilddHS---LKIRKVTAGDMGSYTCVAENMVGKIEASATLT 82


                 .
gi 20127422  310 V 310
Cdd:cd05725   83 V 83

agrin-responsive second immunoglobulin-like domains (Ig2) of the Muscle-specific kinase (MuSK) ectodomain; a member of the I-set of Ig superfamily domains; The members here are composed of the second immunoglobulin-like (Ig) domains of the Muscle-specific kinase (MuSK) ectodomain. MuSK is a receptor tyrosine kinase specifically expressed in skeletal muscle, where it plays a central role in the formation and maintenance of the neuromuscular junction (NMJ). MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. The activation of MUSK in myotubes regulates the formation of NMJs through the regulation of different processes including the specific expression of genes in subsynaptic nuclei, the reorganization of the actin cytoskeleton and the clustering of the acetylcholine receptors (AChR) in the postsynaptic membrane. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the MuSK lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409560 [Multi-domain] Cd Length: 88 Bit Score: 57.64 E-value: 6.11e-10

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 20127422 1304 VLPCKAVGDPSPAVKWMKDSngtpSLVTIDGRRSIFSNGSFIIRTVKAEDSGYYSCIANNNWGS 1367
Cdd:cd20968   18 VLPCTTMGNPKPSVSWIKGD----DLIKENNRIAVLESGSLRIHNVQKEDAGQYRCVAKNSLGI 77

Fifth immunoglobulin (Ig) domain of contactin; The members here are composed of the fifth immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409358 [Multi-domain] Cd Length: 89 Bit Score: 57.47 E-value: 7.12e-10

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 20127422 1302 DIVLPCKAVGDPSPAVKWMKdsnGTpSLVTIDGRRSIFSNGSFIIRTVKAEDSGYYSCIANNNWGSDEIILNLQV 1376
Cdd:cd04969   19 DVIIECKPKASPKPTISWSK---GT-ELLTNSSRICILPDGSLKIKNVTKSDEGKYTCFAVNFFGKANSTGSLSV 89

Fourth immunoglobulin (Ig)-like domain of hemolin, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain of hemolin and similar proteins. Hemolin, an insect immunoglobulin superfamily (IgSF) member containing four Ig-like domains, is a lipopolysaccharide-binding immune protein induced during bacterial infection. Hemolin shares significant sequence similarity with the first four Ig-like domains of the transmembrane cell adhesion molecules (CAMs) of the L1 family. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The fourth Ig-like domain of hemolin is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409570 [Multi-domain] Cd Length: 88 Bit Score: 57.40 E-value: 7.40e-10

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  690 PKFVVQPRDQDGIY-GKAVILNCSAEGYPVPTIVWkFSKGagvpqfQPI-ALNGRIQVlSNGSLLIKHVVEEDSGYYLCK 767
Cdd:cd20978    1 PKFIQKPEKNVVVKgGQDVTLPCQVTGVPQPKITW-LHNG------KPLqGPMERATV-EDGTLTIINVQPEDTGYYGCV 72

                         90
                 ....*....|....*..
gi 20127422  768 VSNDVGaDVSKSMYLTV 784
Cdd:cd20978   73 ATNEIG-DIYTETLLHV 88

Third immunoglobulin (Ig) domain of contactin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409357 [Multi-domain] Cd Length: 88 Bit Score: 57.17 E-value: 8.08e-10

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 20127422  236 AMAGQRVELPCKALGHPEPDYRWLK-DNMPleLSGRFQKTVTGLL-IENIRPSDSGSYVCEVSNRYGTAKVIGRLYV 310
Cdd:cd04968   13 ALKGQTVTLECFALGNPVPQIKWRKvDGSP--SSQWEITTSEPVLeIPNVQFEDEGTYECEAENSRGKDTVQGRIIV 87

Third immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, and Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409390 [Multi-domain] Cd Length: 83 Bit Score: 57.02 E-value: 9.99e-10

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 20127422 1303 IVLPCKAVGDPSPAVKWMKDSNGTPslvtiDGRRSIFSNGSFIIRTVKAEDSGYYSCIANNNWGSDEIILNLQV 1376
Cdd:cd05725   15 AEFQCEVGGDPVPTVRWRKEDGELP-----KGRYEILDDHSLKIRKVTAGDMGSYTCVAENMVGKIEASATLTV 83

Immunoglobulin I-set domain;

Pssm-ID: 400151 [Multi-domain] Cd Length: 90 Bit Score: 56.88 E-value: 1.16e-09

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422    504 PASIRPMKNITAIAGRDTYIHCRVIGYPYYSIKWYKN-SNLLPFNHRQVAFE-NNGTLKLSDVQKEvDEGEYTCNVLVqp 581
Cdd:pfam07679    1 PKFTQKPKDVEVQEGESARFTCTVTGTPDPEVSWFKDgQPLRSSDRFKVTYEgGTYTLTISNVQPD-DSGKYTCVATN-- 77

                           90
                   ....*....|....
gi 20127422    582 qLSTSQSVHVTVKV 595
Cdd:pfam07679   78 -SAGEAEASAELTV 90

Fibronectin type 3 domain; One of three types of internal repeat within the plasma protein, fibronectin. The tenth fibronectin type III repeat contains a RGD cell recognition sequence in a flexible loop between 2 strands. Type III modules are present in both extracellular and intracellular proteins.

Pssm-ID: 214495 [Multi-domain] Cd Length: 83 Bit Score: 56.47 E-value: 1.26e-09

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422    1091 PPENVQAIATSPESISISWSTLSKEALNGILQGFRVIYWAnlmDGELGEIKNITTTQPSLELDGLEKYTNYSIQVLAFTR 1170
Cdd:smart00060    3 PPSNLRVTDVTSTSVTLSWEPPPDDGITGYIVGYRVEYRE---EGSEWKEVNVTPSSTSYTLTGLKPGTEYEFRVRAVNG 79


                    ....
gi 20127422    1171 AGDG 1174
Cdd:smart00060   80 AGEG 83

Fibronectin type III domain;

Pssm-ID: 394996 [Multi-domain] Cd Length: 85 Bit Score: 56.65 E-value: 1.33e-09

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422   1190 GPPAGVKAAAASASMVFVSWLPPLKLNGIIRKYTVFCSHPY-PTVISEFEASPDSFSYRIPNLSRNRQYSVWVVAVTSAG 1268
Cdd:pfam00041    1 SAPSNLTVTDVTSTSLTVSWTPPPDGNGPITGYEVEYRPKNsGEPWNEITVPGTTTSVTLTGLKPGTEYEVRVQAVNGGG 80


                   ....*
gi 20127422   1269 RGNSS 1273
Cdd:pfam00041   81 EGPPS 85

Third immunoglobulin (Ig)-like domain of peroxidasin; The members here are composed of the third immunoglobulin (Ig)-like domain in peroxidasin. Peroxidasin has a peroxidase domain and interacting extracellular motifs containing four Ig-like domains. It has been suggested that peroxidasin is secreted and has functions related to the stabilization of the extracellular matrix. It may play a part in various other important processes such as removal and destruction of cells which have undergone programmed cell death and protection of the organism against non-self.

Pssm-ID: 143222 [Multi-domain] Cd Length: 74 Bit Score: 56.10 E-value: 1.44e-09

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  704 GKAVILNCSAEGYPVPTIVWkfSKGAGvpqfqPIALNGRIQVLSNGSLLIKHVVEEDSGYYLCKVSNDVGAdVSKSMYLT 783
Cdd:cd05745    2 GQTVDFLCEAQGYPQPVIAW--TKGGS-----QLSVDRRHLVLSSGTLRISRVALHDQGQYECQAVNIVGS-QRTVAQLT 73


                 .
gi 20127422  784 V 784
Cdd:cd05745   74 V 74

Immunoglobulin (Ig)-like I-set domain of Neural Cell Adhesion Molecule 1 (NCAM-1); The members here are composed of the fourth Ig domain of Neural Cell Adhesion Molecule 1(NCAM-1). NCAM plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM) and heterophilic (NCAM-non-NCAM) interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves Ig1, Ig2, and Ig3. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions), through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain. One of the unique features of I-set domains is the lack of a C" strand. The structures of this group show that the Ig domain lacks this strand and thus is a member of the I-set of Ig domains.

Pssm-ID: 143277 [Multi-domain] Cd Length: 97 Bit Score: 56.53 E-value: 1.85e-09

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  707 VILNCSAEGYPVPTIVWKFSKGAGVPQFQpiALNGRIQVLSN---GSLLIKHVVEEDSGYYLCKVSNDVGADvSKSMYLT 783
Cdd:cd05869   20 ITLTCEASGDPIPSITWRTSTRNISSEEK--TLDGHIVVRSHarvSSLTLKYIQYTDAGEYLCTASNTIGQD-SQSMYLE 96


                 .
gi 20127422  784 V 784
Cdd:cd05869   97 V 97

Immunoglobulin I-set domain of the Leucine-rich repeat and immunoglobin-like domain-containing protein 1 (Lingo-1); The members here are composed of the immunoglobulin I-set (IgI) domain of the Leucine-rich repeat and immunoglobin-like domain-containing protein 1 (Lingo-1). Human Lingo-1 is a central nervous system-specific transmembrane glycoprotein also known as LERN-1, which functions as a negative regulator of neuronal survival, axonal regeneration, and oligodendrocyte differentiation and myelination. Lingo-1 is a key component of the Nogo receptor signaling complex (RTN4R/NGFR) in RhoA activation responsible for some inhibition of axonal regeneration by myelin-associated factors. The ligand-binding ectodomain of human Lingo-1 contains a bimodular, kinked structure composed of leucine-rich repeat (LRR) and immunoglobulin (Ig)-like modules. Diseases associated with Lingo-1 include mental retardation, autosomal recessive 64 and essential tremor. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the Lingo-1 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409561 Cd Length: 92 Bit Score: 56.24 E-value: 1.92e-09

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  694 VQPRDQDGIY---GKAVILNCSAEGYPVPTIVWKFskgagvPQFQPIAL--NGRIQVLSNGSLLIKHVVEEDSGYYLCKV 768
Cdd:cd20969    4 IRDRKAQQVFvdeGHTVQFVCRADGDPPPAILWLS------PRKHLVSAksNGRLTVFPDGTLEVRYAQVQDNGTYLCIA 77


                 ....*..
gi 20127422  769 SNDVGAD 775
Cdd:cd20969   78 ANAGGND 84

Third immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the Constant 2 (C2)-set of IgSF domains; The members here are composed of the third immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. This group belongs to the C2-set of IgSF domains, having A, B, and E strands in one beta-sheet and A', G, F, C, and C' in the other. Unlike other Ig domain sets, the C2-set lacks the D strand.

Pssm-ID: 409549 [Multi-domain] Cd Length: 88 Bit Score: 55.62 E-value: 3.11e-09

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  689 PPKFVVQPRDQDGIYGKAVILNCSAEGYPVPTIVWKFSKgagvpqfQPIALNGRIQVLSNGSLLIKHVVEEDSGYYLCKV 768
Cdd:cd20957    1 PLSATIDPPVQTVDFGRTAVFNCSVTGNPIHTVLWMKDG-------KPLGHSSRVQILSEDVLVIPSVKREDKGMYQCFV 73


                 ....
gi 20127422  769 SNDV 772
Cdd:cd20957   74 RNDG 77

Immunoglobulin domain; The members here are composed of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. Members of this group are components of immunoglobulin, neuroglia, cell surface glycoproteins, including T-cell receptors, CD2, CD4, CD8, and membrane glycoproteins, including butyrophilin and chondroitin sulfate proteoglycan core protein. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. Ig superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Typically, the V-set domains have A, B, E, and D strands in one sheet and A', G, F, C, C' and C" in the other. The structures in C1-set are smaller than those in the V-set; they have one beta sheet that is formed by strands A, B, E, and D and the other by strands G, F, C, and C'. Moreover, a C1-set Ig domain contains a short C' strand (three residues) and lacks A' and C" strand. Unlike other Ig domain sets, C2-set structures do not have a D strand. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409353 [Multi-domain] Cd Length: 70 Bit Score: 55.03 E-value: 3.42e-09

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 20127422  523 IHCRVIGYPYYSIKWYKNSNLLPFNHRQVAFE--NNGTLKLSDVQKEvDEGEYTCNVLVQPQLSTSQSV 589
Cdd:cd00096    3 LTCSASGNPPPTITWYKNGKPLPPSSRDSRRSelGNGTLTISNVTLE-DSGTYTCVASNSAGGSASASV 70

Seventh immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the seventh immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409546 [Multi-domain] Cd Length: 96 Bit Score: 55.78 E-value: 3.45e-09

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1277 TVEPLAKAPARiltfsgtvttpwMKDIVLPCKAVGDPSPAVKWMKDSNGTPSL---VTIDGRRSIFSNGSFIIRTVKAED 1353
Cdd:cd20954    5 IVEPVDANVAA------------GQDVMLHCQADGFPTPTVTWKKATGSTPGEykdLLYDPNVRILPNGTLVFGHVQKEN 72

                         90
                 ....*....|....*
gi 20127422 1354 SGYYSCIANNNWGSD 1368
Cdd:cd20954   73 EGHYLCEAKNGIGSG 87

Third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM), and similar domains; The members here are composed of the third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, and spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM and human neurofascin.

Pssm-ID: 409394 [Multi-domain] Cd Length: 83 Bit Score: 54.72 E-value: 5.06e-09

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 20127422  236 AMAGQRVELPCKALGHPEPDYRWLKDNMPLeLSGR-----FQKTvtgLLIENIRPSDSGSYVCEVSNRYGTAK 303
Cdd:cd05731    7 VLRGGVLLLECIAEGLPTPDIRWIKLGGEL-PKGRtkfenFNKT---LKIENVSEADSGEYQCTASNTMGSAR 75

Immunoglobulin I-set domain;

Pssm-ID: 400151 [Multi-domain] Cd Length: 90 Bit Score: 54.96 E-value: 5.64e-09

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 20127422    315 KATISPRKVKSSVGSQVSLSCSVTGTEDQELSWYRNGEILNPGKNVRIT--GINHEnLIMDHMVKSDGGAYQC 385
Cdd:pfam07679    2 KFTQKPKDVEVQEGESARFTCTVTGTPDPEVSWFKDGQPLRSSDRFKVTyeGGTYT-LTISNVQPDDSGKYTC 73

Fourth immunoglobulin (Ig)-like domain of hemolin, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain of hemolin and similar proteins. Hemolin, an insect immunoglobulin superfamily (IgSF) member containing four Ig-like domains, is a lipopolysaccharide-binding immune protein induced during bacterial infection. Hemolin shares significant sequence similarity with the first four Ig-like domains of the transmembrane cell adhesion molecules (CAMs) of the L1 family. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The fourth Ig-like domain of hemolin is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409570 [Multi-domain] Cd Length: 88 Bit Score: 54.71 E-value: 6.59e-09

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  596 PPFIQPFEFPR-FSIGQRVFIPCVVvSGDLPITITWQKDGRPIPGSLGvtidNIDFT-SSLRISNLSLMHNGNYTCIARN 673
Cdd:cd20978    1 PKFIQKPEKNVvVKGGQDVTLPCQV-TGVPQPKITWLHNGKPLQGPME----RATVEdGTLTIINVQPEDTGYYGCVATN 75

                         90
                 ....*....|...
gi 20127422  674 EAAAVEHQSQLIV 686
Cdd:cd20978   76 EIGDIYTETLLHV 88

Immunoglobulin like; IG domains that cannot be classified into one of IGv1, IGc1, IGc2, IG.

Pssm-ID: 214653 [Multi-domain] Cd Length: 85 Bit Score: 54.43 E-value: 7.03e-09

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422     511 KNITAIAGRDTYIHCRVIGYPYYSIKWYKNS-NLLPFNHRQVAFENNG--TLKLSDVQKEvDEGEYTCNVLVqPQLSTSQ 587
Cdd:smart00410    2 PSVTVKEGESVTLSCEASGSPPPEVTWYKQGgKLLAESGRFSVSRSGStsTLTISNVTPE-DSGTYTCAATN-SSGSASS 79


                    ....*.
gi 20127422     588 SVHVTV 593
Cdd:smart00410   80 GTTLTV 85

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor. FGF receptors bind FGF signaling polypeptides. FGFs participate in multiple processes such as morphogenesis, development, and angiogenesis. FGFs bind to four FGF receptor tyrosine kinases (FGFR1, FGFR2, FGFR3, FGFR4). Receptor diversity is controlled by alternative splicing producing splice variants with different ligand binding characteristics and different expression patterns. FGFRs have an extracellular region comprised of three IG-like domains, a single transmembrane helix, and an intracellular tyrosine kinase domain. Ligand binding and specificity reside in the Ig-like domains 2 and 3, and the linker region that connects these two. FGFR activation and signaling depend on FGF-induced dimerization, a process involving cell surface heparin or heparin sulfate proteoglycans.

Pssm-ID: 409443 [Multi-domain] Cd Length: 95 Bit Score: 54.47 E-value: 9.30e-09

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 20127422  238 AGQRVELPCKALGHPEPDYRWLKDNMPLELSGR-----FQKTVTGLLIENIRPSDSGSYVCEVSNRYGT 301
Cdd:cd05857   18 AANTVKFRCPAAGNPTPTMRWLKNGKEFKQEHRiggykVRNQHWSLIMESVVPSDKGNYTCVVENEYGS 86

Fourth Ig domain of the neural cell adhesion molecule contactin-2, and similar domains; The members here are composed of the fourth Ig domain of the neural cell adhesion molecule contactin-2. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-2 (also called TAG-1, axonin-1) facilitates cell adhesion by homophilic binding between molecules in apposed membranes. The first four Ig domains form the intermolecular binding fragment which arranges as a compact U-shaped module by contacts between Ig domains 1 and 4, and domains 2 and 3. It has been proposed that a linear zipper-like array forms, from contactin-2 molecules alternatively provided by the two apposed membranes.

Pssm-ID: 143205 [Multi-domain] Cd Length: 85 Bit Score: 54.14 E-value: 9.92e-09

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 20127422 1307 CKAVGDPSPAVKWMKDSNGTPSlvtiDGRRSIfSNGSFIIRTVKAEDSGYYSCIANNNWGS 1367
Cdd:cd05728   21 CKASGNPRPAYRWLKNGQPLAS----ENRIEV-EAGDLRITKLSLSDSGMYQCVAENKHGT 76

agrin-responsive first immunoglobulin-like domains (Ig1) of the MuSK ectodomain; a member of the I-set of IgSF domains; The members here are composed of the first immunoglobulin-like domains (Ig1) of the Muscle-specific kinase (MuSK). MuSK is a receptor tyrosine kinase specifically expressed in skeletal muscle, where it plays a central role in the formation and maintenance of the neuromuscular junction (NMJ). MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. The activation of MUSK in myotubes regulates the formation of NMJs through the regulation of different processes including the specific expression of genes in subsynaptic nuclei, the reorganization of the actin cytoskeleton and the clustering of the acetylcholine receptors (AChR) in the postsynaptic membrane. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the MuSK lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409562 [Multi-domain] Cd Length: 92 Bit Score: 54.05 E-value: 1.17e-08

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1292 SGTVTTPWMKDIVLPCKAVGDPSPAVKWMKDSNgtpSLVTIDGRRSIFSNGS-FIIRTVKAEDSGYYSCIANNN-WGSDE 1369
Cdd:cd20970    9 SFTVTAREGENATFMCRAEGSPEPEISWTRNGN---LIIEFNTRYIVRENGTtLTIRNIRRSDMGIYLCIASNGvPGSVE 85


                 ....*..
gi 20127422 1370 IILNLQV 1376
Cdd:cd20970   86 KRITLQV 92

First immunoglobulin (Ig)-like domain in neogenin, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain in neogenin and related proteins. Neogenin is a cell surface protein which is expressed in the developing nervous system of vertebrate embryos in the growing nerve cells. It is also expressed in other embryonic tissues and may play a general role in developmental processes such as cell migration, cell-cell recognition, and tissue growth regulation. Included in this group is the tumor suppressor protein DCC which is deleted in colorectal carcinoma. DCC and neogenin each have four Ig-like domains followed by six fibronectin type III domains, a transmembrane domain, and an intracellular domain. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409387 Cd Length: 97 Bit Score: 54.02 E-value: 1.43e-08

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 20127422 1303 IVLPCKAVGDPSPAVKWMKDsnGTPSLVTIDGRRSIFSNGSFIIRTVK-----AEDSGYYSCIANN-NWGS 1367
Cdd:cd05722   19 VVLNCSAESDPPPKIEWKKD--GVLLNLVSDERRQQLPNGSLLITSVVhskhnKPDEGFYQCVAQNeSLGS 87

Fifth immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fifth immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409550 [Multi-domain] Cd Length: 89 Bit Score: 53.73 E-value: 1.43e-08

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 20127422 1301 KDIVLPCKAVGDPSPAVKWMKDSNGTPslvtIDGRRSIFSNGSFIIRTV-KAEDSGYYSCIANNNWG-SDEIILNLQV 1376
Cdd:cd20958   16 QTLRLHCPVAGYPISSITWEKDGRRLP----LNHRQRVFPNGTLVIENVqRSSDEGEYTCTARNQQGqSASRSVFVKV 89

Immunoglobulin like; IG domains that cannot be classified into one of IGv1, IGc1, IGc2, IG.

Pssm-ID: 214653 [Multi-domain] Cd Length: 85 Bit Score: 53.66 E-value: 1.45e-08

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422     320 PRKVKSSVGSQVSLSCSVTGTEDQELSWYRNG-EILNPGKNVRITG-INHENLIMDHMVKSDGGAYQCFVRKDKLSAQDY 397
Cdd:smart00410    1 PPSVTVKEGESVTLSCEASGSPPPEVTWYKQGgKLLAESGRFSVSRsGSTSTLTISNVTPEDSGTYTCAATNSSGSASSG 80


                    ...
gi 20127422     398 VQV 400
Cdd:smart00410   81 TTL 83

Immunoglobulin (Ig)-like I-set domain of Neural Cell Adhesion Molecule 2 (NCAM-2); The members here are composed of the fourth Ig domain of Neural Cell Adhesion Molecule NCAM-2 (also known as OCAM/mamFas II and RNCAM). NCAM-2 is organized similarly to NCAM, including five N-terminal Ig-like domains and two fibronectin type III domains. NCAM-2 is differentially expressed in the developing and mature olfactory epithelium (OE), and may function like NCAM, as an adhesion molecule. One of the unique features of I-set domains is the lack of a C" strand. The structures of this group show that the Ig domain lacks this strand and thus is a member of the I-set of Ig domains.

Pssm-ID: 143278 [Multi-domain] Cd Length: 98 Bit Score: 54.21 E-value: 1.50e-08

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  693 VVQPRDQDGIYGKAVILNCSAEGYPVPTIVWK-------FSKGAGVPqfqpialNGRIQV---LSNGSLLIKHVVEEDSG 762
Cdd:cd05870    5 IIQLKNETTVENGAATLSCKAEGEPIPEITWKrasdghtFSEGDKSP-------DGRIEVkgqHGESSLHIKDVKLSDSG 77

                         90       100
                 ....*....|....*....|..
gi 20127422  763 YYLCKVSNDVGADvSKSMYLTV 784
Cdd:cd05870   78 RYDCEAASRIGGH-QKSMYLDI 98

Fourth immunoglobulin (Ig)-like domain of peroxidasin; The members here are composed of the fourth immunoglobulin (Ig)-like domain in peroxidasin. Peroxidasin has a peroxidase domain and interacting extracellular motifs containing four Ig-like domains. It has been suggested that peroxidasin is secreted, and has functions related to the stabilization of the extracellular matrix. It may play a part in various other important processes such as removal and destruction of cells which have undergone programmed cell death and protection of the organism against non-self.

Pssm-ID: 143223 Cd Length: 69 Bit Score: 52.95 E-value: 1.66e-08

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 20127422 1303 IVLPCKAVGDPSPAVKWMKDSngtpSLVTIDGRRSIFSNGSFIIRTVKAEDSGYYSCIANNNWGSDEIILNL 1374
Cdd:cd05746    1 VQIPCSAQGDPEPTITWNKDG----VQVTESGKFHISPEGYLAIRDVGVADQGRYECVARNTIGYASVSMVL 68

Fourth immunoglobulin (Ig)-like domain of NrCAM (NgCAM-related cell adhesion molecule); The members here are composed of the fourth immunoglobulin (Ig)-like domain of NrCAM (NgCAM-related cell adhesion molecule). NrCAM belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six IG-like domains and five fibronectin type III domains, a transmembrane region, and an intracellular domain. NrCAM is primarily expressed in the nervous system.

Pssm-ID: 409454 Cd Length: 89 Bit Score: 53.45 E-value: 1.71e-08

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  410 ISAFSEKVVSPAEPVSLMCNVKGTPLPTITWTLDDDPIL---KGGSHRIsqmitsEGNVVSYLNIsssQVRDGGVYRCTA 486
Cdd:cd05868    3 ITAPTNLVLSPGEDGTLICRANGNPKPSISWLTNGVPIEiapTDPSRKV------DGDTIIFSKV---QERSSAVYQCNA 73

                         90
                 ....*....|....*
gi 20127422  487 NNSAGVVLYQARINV 501
Cdd:cd05868   74 SNEYGYLLANAFVNV 88

Second immunoglobulin (Ig)-like domain of the receptor protein tyrosine phosphatase (RPTP)-F; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain found in the receptor protein tyrosine phosphatase (RPTP)-F, also known as LAR. LAR belongs to the RPTP type IIa subfamily. Members of this subfamily are cell adhesion molecule-like proteins involved in central nervous system (CNS) development. They have large extracellular portions comprised of multiple Ig-like domains and two to nine fibronectin type III (FNIII) domains and a cytoplasmic portion having two tandem phosphatase domains.

Pssm-ID: 409400 [Multi-domain] Cd Length: 91 Bit Score: 53.48 E-value: 1.85e-08

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 20127422  246 CKALGHPEPDYRWLKDNMPLELS---GRFQKTVTGLL-IENIRPSDSGSYVCEVSNRYGTA-KVIGRLYVK 311
Cdd:cd05738   21 CAASGNPDPEISWFKDFLPVDTAtsnGRIKQLRSGALqIENSEESDQGKYECVATNSAGTRySAPANLYVR 91

Fourth Ig-like domain from smooth muscle myosin light chain kinase and similar domains ; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain from smooth muscle myosin light chain kinase (MYLK) and similar domains. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of this group shows that the fourth Ig-like domain from myosin light chain kinase lacks this strand and thus belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409568 [Multi-domain] Cd Length: 90 Bit Score: 53.41 E-value: 2.01e-08

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  689 PPKFVVQPRDQDGIYGKAVILNCSAEGYPVPTIVWkfskgagVPQFQPIALNG-RIQV-LSNGSLLIKHVVEEDSGYYLC 766
Cdd:cd20976    1 APSFSSVPKDLEAVEGQDFVAQCSARGKPVPRITW-------IRNAQPLQYAAdRSTCeAGVGELHIQDVLPEDHGTYTC 73

                         90
                 ....*....|....*...
gi 20127422  767 KVSNDVGAdVSKSMYLTV 784
Cdd:cd20976   74 LAKNAAGQ-VSCSAWVTV 90

First immunoglobulin (Ig)-like constant domain in Robo (roundabout) receptors, and similar domains; The members here are composed of the first immunoglobulin (Ig)-like domain in Roundabout (Robo) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit1, Slit2, Slit3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit1, Slit2,and Slit3 are expressed at the ventral midline. Robo3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be is the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site.

Pssm-ID: 409490 [Multi-domain] Cd Length: 99 Bit Score: 53.71 E-value: 2.27e-08

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  407 PKIISAFSEKVVSPAEPVSLMCNVKGTPLPTITWTLDDDPI----LKGGSHRisqMITSEGNVVSYLNISSSQVR-DGGV 481
Cdd:cd07693    1 PRIVEHPSDLIVSKGDPATLNCKAEGRPTPTIQWLKNGQPLetdkDDPRSHR---IVLPSGSLFFLRVVHGRKGRsDEGV 77

                         90
                 ....*....|.
gi 20127422  482 YRCTANNSAGV 492
Cdd:cd07693   78 YVCVAHNSLGE 88

Fourth Ig-like domain from smooth muscle myosin light chain kinase and similar domains ; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain from smooth muscle myosin light chain kinase (MYLK) and similar domains. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of this group shows that the fourth Ig-like domain from myosin light chain kinase lacks this strand and thus belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409568 [Multi-domain] Cd Length: 90 Bit Score: 53.02 E-value: 2.51e-08

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  224 APSILDGFDHRKAMAGQRVELPCKALGHPEPDYRWLKDNMPLELSG-RFQKTV-TGLL-IENIRPSDSGSYVCEVSNRYG 300
Cdd:cd20976    1 APSFSSVPKDLEAVEGQDFVAQCSARGKPVPRITWIRNAQPLQYAAdRSTCEAgVGELhIQDVLPEDHGTYTCLAKNAAG 80

                         90
                 ....*....|
gi 20127422  301 TAKVIGRLYV 310
Cdd:cd20976   81 QVSCSAWVTV 90

Immunoglobulin domain; This family contains immunoglobulin-like domains.

Pssm-ID: 464046 [Multi-domain] Cd Length: 78 Bit Score: 52.57 E-value: 3.14e-08

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 20127422    511 KNITAIAGRDTYIHCRVIGYPYYSIKWYKNSNLLPFNHRQVAFE--NNGTLKLSDVQKEvDEGEYTCNV 577
Cdd:pfam13927    9 SSVTVREGETVTLTCEATGSPPPTITWYKNGEPISSGSTRSRSLsgSNSTLTISNVTRS-DAGTYTCVA 76

agrin-responsive second immunoglobulin-like domains (Ig2) of the Muscle-specific kinase (MuSK) ectodomain; a member of the I-set of Ig superfamily domains; The members here are composed of the second immunoglobulin-like (Ig) domains of the Muscle-specific kinase (MuSK) ectodomain. MuSK is a receptor tyrosine kinase specifically expressed in skeletal muscle, where it plays a central role in the formation and maintenance of the neuromuscular junction (NMJ). MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. The activation of MUSK in myotubes regulates the formation of NMJs through the regulation of different processes including the specific expression of genes in subsynaptic nuclei, the reorganization of the actin cytoskeleton and the clustering of the acetylcholine receptors (AChR) in the postsynaptic membrane. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the MuSK lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409560 [Multi-domain] Cd Length: 88 Bit Score: 52.63 E-value: 3.24e-08

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  508 RPMKNITAIAGRDTYIHCRVIGYPYYSIKWYKNSNLLPFNHRqVAFENNGTLKLSDVQKEvDEGEYTCnvLVQPQLSTSQ 587
Cdd:cd20968    4 RPPTNVTIIEGLKAVLPCTTMGNPKPSVSWIKGDDLIKENNR-IAVLESGSLRIHNVQKE-DAGQYRC--VAKNSLGIAY 79


                 ....*...
gi 20127422  588 SVHVTVKV 595
Cdd:cd20968   80 SKPVTIEV 87

Third immunoglobulin (Ig) domain of contactin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409357 [Multi-domain] Cd Length: 88 Bit Score: 52.55 E-value: 3.50e-08

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  407 PKIISAFSEKVVS-PAEPVSLMCNVKGTPLPTITWTLDDDPIlkggshrISQMITSEGNVVsyLNISSSQVRDGGVYRCT 485
Cdd:cd04968    1 PSIKVRFPADTYAlKGQTVTLECFALGNPVPQIKWRKVDGSP-------SSQWEITTSEPV--LEIPNVQFEDEGTYECE 71

                         90
                 ....*....|....*.
gi 20127422  486 ANNSAGVVLYQARINV 501
Cdd:cd04968   72 AENSRGKDTVQGRIIV 87

Fifth immunoglobulin (Ig) domain of contactin; The members here are composed of the fifth immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409358 [Multi-domain] Cd Length: 89 Bit Score: 52.85 E-value: 3.53e-08

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  704 GKAVILNCSAEGYPVPTIVWKFSKGAgvpqfqpIALNGRIQVLSNGSLLIKHVVEEDSGYYLCKVSNDVGAdVSKSMYLT 783
Cdd:cd04969   17 GGDVIIECKPKASPKPTISWSKGTEL-------LTNSSRICILPDGSLKIKNVTKSDEGKYTCFAVNFFGK-ANSTGSLS 88


                 .
gi 20127422  784 V 784
Cdd:cd04969   89 V 89

Immunoglobulin domain; This family contains immunoglobulin-like domains.

Pssm-ID: 464046 [Multi-domain] Cd Length: 78 Bit Score: 52.18 E-value: 3.64e-08

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 20127422    317 TISPRKVKSSVGSQVSLSCSVTGTEDQELSWYRNGEILNPGKN-VRITGINHENLIMDHMVKSDGGAYQCFVR 388
Cdd:pfam13927    5 TVSPSSVTVREGETVTLTCEATGSPPPTITWYKNGEPISSGSTrSRSLSGSNSTLTISNVTRSDAGTYTCVAS 77

Fifth immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fifth immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409550 [Multi-domain] Cd Length: 89 Bit Score: 52.57 E-value: 3.66e-08

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  236 AMAGQRVELPCKALGHPEPDYRWLKDNMPLELSGRfQKTVTG--LLIENI-RPSDSGSYVCEVSNRYG-TAKviGRLYVK 311
Cdd:cd20958   12 AVAGQTLRLHCPVAGYPISSITWEKDGRRLPLNHR-QRVFPNgtLVIENVqRSSDEGEYTCTARNQQGqSAS--RSVFVK 88

Fourth immunoglobulin (Ig)-like domain of L1, Ng-CAM (Neuron-glia CAM cell adhesion molecule), and NrCAM (Ng-CAM-related); The members here are composed of the fourth immunoglobulin (Ig)-like domain of L1, Ng-CAM (Neuron-glia CAM cell adhesion molecule), and NrCAM (Ng-CAM-related). These proteins belong to the L1 subfamily of cell adhesion molecules (CAMs) and are comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. These molecules are primarily expressed in the nervous system. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth.

Pssm-ID: 409367 [Multi-domain] Cd Length: 89 Bit Score: 52.45 E-value: 3.70e-08

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  417 VVSPAEPVSLMCNVKGTPLPTITWTLDDDPILKGGSHRISqmiTSEGNVVSYLNISSsqvRDGGVYRCTANNSAGVVLYQ 496
Cdd:cd04978   10 VLSPGETGELICEAEGNPQPTITWRLNGVPIEPAPEDMRR---TVDGRTLIFSNLQP---NDTAVYQCNASNVHGYLLAN 83


                 ....*.
gi 20127422  497 ARINVR 502
Cdd:cd04978   84 AFLHVL 89

Immunoglobulin domain; This family contains immunoglobulin-like domains.

Pssm-ID: 464046 [Multi-domain] Cd Length: 78 Bit Score: 52.18 E-value: 3.75e-08

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422    790 ITSYPNTTLATQGQKKEMSCTAHGEKPIIVRWEKEDRIINPEMARYLVSTKEVgeeviSTLQILPTVREDSGFFSCHAIN 869
Cdd:pfam13927    4 ITVSPSSVTVREGETVTLTCEATGSPPPTITWYKNGEPISSGSTRSRSLSGSN-----STLTISNVTRSDAGTYTCVASN 78

Second immunoglobulin (Ig)-like domain of a Follistatin-related protein 5, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain found in human Follistatin-related protein 5 (FSTL5) and a follistatin-like molecule encoded by the CNS-related Mahya gene. Mahya genes have been retained in certain Bilaterian branches during evolution. They are conserved in Hymenoptera and Deuterostomes, but are absent from other metazoan species such as fruit fly and nematode. Mahya proteins are secretory, with a follistatin-like domain (Kazal-type serine/threonine protease inhibitor domain and EF-hand calcium-binding domain), two Ig-like domains, and a novel C-terminal domain. Mahya may be involved in learning and memory and in processing of sensory information in Hymenoptera and vertebrates. Follistatin is a secreted, multidomain protein that binds activins with high affinity and antagonizes their signaling.

Pssm-ID: 409399 [Multi-domain] Cd Length: 93 Bit Score: 52.65 E-value: 3.80e-08

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 20127422 1305 LPCKAVGDPSPAVKWMKdsNGTPSLVTIDGRRSIFSNGS-FIIRTVKAEDSGYYSCIANNNWGSDEIILNLQVQ 1377
Cdd:cd05736   20 LRCHAEGIPLPRVQWLK--NGMDINPKLSKQLTLIANGSeLHISNVRYEDTGAYTCIAKNEGGVDEDISSLFVE 91

agrin-responsive second immunoglobulin-like domains (Ig2) of the Muscle-specific kinase (MuSK) ectodomain; a member of the I-set of Ig superfamily domains; The members here are composed of the second immunoglobulin-like (Ig) domains of the Muscle-specific kinase (MuSK) ectodomain. MuSK is a receptor tyrosine kinase specifically expressed in skeletal muscle, where it plays a central role in the formation and maintenance of the neuromuscular junction (NMJ). MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. The activation of MUSK in myotubes regulates the formation of NMJs through the regulation of different processes including the specific expression of genes in subsynaptic nuclei, the reorganization of the actin cytoskeleton and the clustering of the acetylcholine receptors (AChR) in the postsynaptic membrane. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the MuSK lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409560 [Multi-domain] Cd Length: 88 Bit Score: 52.63 E-value: 4.02e-08

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  696 PRDQDGIYGKAVILNCSAEGYPVPTIVWkfSKGAGVpqfqpIALNGRIQVLSNGSLLIKHVVEEDSGYYLCKVSNDVGAD 775
Cdd:cd20968    6 PTNVTIIEGLKAVLPCTTMGNPKPSVSW--IKGDDL-----IKENNRIAVLESGSLRIHNVQKEDAGQYRCVAKNSLGIA 78

                         90
                 ....*....|
gi 20127422  776 VSKSMYLTVK 785
Cdd:cd20968   79 YSKPVTIEVE 88

Immunoglobulin (Ig)-like domain in neuregulins; The members here are composed of the immunoglobulin (Ig)-like domain in neuregulins (NRGs). NRGs are signaling molecules which participate in cell-cell interactions in the nervous system, breast, heart, and other organ systems, and are implicated in the pathology of diseases including schizophrenia, multiple sclerosis, and breast cancer. There are four members of the neuregulin gene family (NRG-1, NRG-2, NRG-3, and NRG-4). The NRG-1 protein, binds to and activates the tyrosine kinases receptors ErbB3 and ErbB4, initiating signaling cascades. The other NRGs proteins bind one or the other or both of these ErbBs. NRG-1 has multiple functions: in the brain it regulates various processes such as radial glia formation and neuronal migration, dendritic development, and expression of neurotransmitters receptors, while in the peripheral nervous system NRG-1 regulates processes such as target cell differentiation, and Schwann cell survival. There are many NRG-1 isoforms which arise from the alternative splicing of mRNA. Less is known of the functions of the other NRGs. NRG-2 and NRG-3 are expressed predominantly in the nervous system. NRG-2 is expressed by motor neurons and terminal Schwann cells, and is concentrated near synaptic sites and may be a signal that regulates synaptic differentiation. NRG-4 has been shown to direct pancreatic islet cell development towards the delta-cell lineage.

Pssm-ID: 409408 [Multi-domain] Cd Length: 92 Bit Score: 52.51 E-value: 4.23e-08

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  238 AGQRVELPCKALG-HPEPDYRWLKD------NMPLELSGRFQKTVTGLLIENIRPSDSGSYVCEVSNRYGTAKVIGRLYV 310
Cdd:cd05750   13 EGSKLVLKCEATSeNPSPRYRWFKDgkelnrKRPKNIKIRNKKKNSELQINKAKLEDSGEYTCVVENILGKDTVTGNVTV 92

Immunoglobulin (Ig)-like domain of titin and similar proteins; The members here are composed of the immunoglobulin (Ig)-like domain found in titin-like proteins and similar proteins. Titin (also called connectin) is a fibrous sarcomeric protein specifically found in vertebrate striated muscle. Titin is a giant protein; depending on isoform composition, it ranges from 2970 to 3700 kDa, and is of a length that spans half a sarcomere. Titin largely consists of multiple repeats of Ig-like and fibronectin type 3 (FN-III)-like domains. Titin connects the ends of myosin thick filaments to Z disks and extends along the thick filament to the H zone. It appears to function similarly to an elastic band, keeping the myosin filaments centered in the sarcomere during muscle contraction or stretching. Within the sarcomere, titin is also attached to or is associated with myosin binding protein C (MyBP-C). MyBP-C appears to contribute to the generation of passive tension by titin and like titin has repeated Ig-like and FN-III domains. Also included in this group are worm twitchin and insect projectin, thick filament proteins of invertebrate muscle which also have repeated Ig-like and FN-III domains.

Pssm-ID: 409406 [Multi-domain] Cd Length: 82 Bit Score: 52.21 E-value: 4.28e-08

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  422 EPVSLMCNVKGTPLPTITWTLDDDPILKGGshRISQMITSEgnvVSYLNISSSQVRDGGVYRCTANNSAGVVlyQARINV 501
Cdd:cd05748    8 ESLRLDIPIKGRPTPTVTWSKDGQPLKETG--RVQIETTAS---STSLVIKNAKRSDSGKYTLTLKNSAGEK--SATINV 80


                 .
gi 20127422  502 R 502
Cdd:cd05748   81 K 81

Fifth immunoglobulin (Ig) domain of contactin; The members here are composed of the fifth immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409358 [Multi-domain] Cd Length: 89 Bit Score: 52.46 E-value: 4.29e-08

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 20127422  236 AMAGQRVELPCKALGHPEPDYRWLKDNMPLELSGRFQKTVTG-LLIENIRPSDSGSYVCEVSNRYGTAKVIGRLYV 310
Cdd:cd04969   14 AAKGGDVIIECKPKASPKPTISWSKGTELLTNSSRICILPDGsLKIKNVTKSDEGKYTCFAVNFFGKANSTGSLSV 89

Fourth immunoglobulin (Ig)-like domain of hemolin, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain of hemolin and similar proteins. Hemolin, an insect immunoglobulin superfamily (IgSF) member containing four Ig-like domains, is a lipopolysaccharide-binding immune protein induced during bacterial infection. Hemolin shares significant sequence similarity with the first four Ig-like domains of the transmembrane cell adhesion molecules (CAMs) of the L1 family. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The fourth Ig-like domain of hemolin is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409570 [Multi-domain] Cd Length: 88 Bit Score: 52.39 E-value: 4.92e-08

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  407 PKIISAF-SEKVVSPAEPVSLMCNVKGTPLPTITWTLDDDPIlkggSHRISQMITSEGNVVsylnISSSQVRDGGVYRCT 485
Cdd:cd20978    1 PKFIQKPeKNVVVKGGQDVTLPCQVTGVPQPKITWLHNGKPL----QGPMERATVEDGTLT----IINVQPEDTGYYGCV 72

                         90
                 ....*....|....*.
gi 20127422  486 ANNSAGVVLYQARINV 501
Cdd:cd20978   73 ATNEIGDIYTETLLHV 88

Immunoglobulin domain of human Synaptic Adhesion-Like Molecule 5 (SALM5) and similar proteins; member of the I-set of IgSF domains; This group contains the immunoglobulin domain of human Synaptic Adhesion-Like Molecule 5 (SALM5) and similar proteins. The SALM (for synaptic adhesion-like molecules; also known as Lrfn for leucine-rich repeat and fibronectin type III domain containing) family of adhesion molecules consists of five known members: SALM1/Lrfn2, SALM2/Lrfn1, SALM3/Lrfn4, SALM4/Lrfn3, and SALM5/Lrfn5. SALMs share a similar domain structure, containing leucine-rich repeats (LRRs), an immunoglobulin (Ig) domain, and a fibronectin III (FNIII) domain, followed by a transmembrane domain and a C-terminal PDZ-binding motif. SALM5 is implicated in autism spectrum disorders (ASDs) and schizophrenia, induces presynaptic differentiation in contacting axons. SALM5 interacts with the Ig domains of LAR (Leukocyte common Antigen-Related) family receptor protein tyrosine phosphatases (LAR-RPTPs; LAR, PTPdelta, and PTPsigma). In addition, PTPdelta is implicated in ASDs, ADHD, bipolar disorder, and restless leg syndrome. Studies have shown that LAR-RPTPs are novel and splicing-dependent presynaptic ligands for SALM5, and that they mediate SALM5-dependent presynaptic differentiation. Furthermore, SALM5 maintains AMPA receptor (AMPAR)-mediated excitatory synaptic transmission through mechanisms involving the interaction of SALM5 with LAR-RPTPs. This group belongs to the I-set of immunoglobulin superfamily (IgSF) domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409421 [Multi-domain] Cd Length: 88 Bit Score: 52.09 E-value: 5.22e-08

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 20127422 1305 LPCKAVGDPSPAVKWMKDSNgtpSLVTIDGRRSIFSNGSFIIRTVKAEDSGYYSCIANNNWGSDEIILNLQV 1376
Cdd:cd05764   20 LRCKARGDPEPAIHWISPEG---KLISNSSRTLVYDNGTLDILITTVKDTGAFTCIASNPAGEATARVELHI 88

Sixth immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the sixth immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409551 Cd Length: 94 Bit Score: 52.49 E-value: 5.33e-08

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  407 PKIIS-AFSEKVVSPAEPVSLMCNVKGTPLP-TITWTLDDDPILKggSHRISqmITSEGNVVSYLNISSSQVRDGGVYRC 484
Cdd:cd20959    2 PRIIPfAFGEGAAQVGMRAQLHCGVPGGDLPlNIRWTLDGQPISD--DLGIT--VSRLGRRSSILSIDSLEASHAGNYTC 77

                         90
                 ....*....|....*..
gi 20127422  485 TANNSAGVVLYQARINV 501
Cdd:cd20959   78 HARNSAGSASYTAPLTV 94

Fourth immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409548 [Multi-domain] Cd Length: 96 Bit Score: 52.18 E-value: 5.93e-08

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 20127422  704 GKAVILNCSAEGYPVPTIVWKFSKgagvpqfQPIALNGRIQ----VLSNGSLL----IKHVVEEDSGYYLCKVSNDVGA 774
Cdd:cd20956   16 GPSVSLKCVASGNPLPQITWTLDG-------FPIPESPRFRvgdyVTSDGDVVsyvnISSVRVEDGGEYTCTATNDVGS 87

Second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of the Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit-2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409389 [Multi-domain] Cd Length: 87 Bit Score: 51.63 E-value: 6.77e-08

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 20127422 1304 VLPCKA-VGDPSPAVKWMKDsnGTPsLVTIDGRRSIFSNGSFIIRTVKAEDSGYYSCIANNNWGSDE 1369
Cdd:cd05724   16 VLECSPpRGHPEPTVSWRKD--GQP-LNLDNERVRIVDDGNLLIAEARKSDEGTYKCVATNMVGERE 79

Fourth immunoglobulin (Ig)-like domain of peroxidasin; The members here are composed of the fourth immunoglobulin (Ig)-like domain in peroxidasin. Peroxidasin has a peroxidase domain and interacting extracellular motifs containing four Ig-like domains. It has been suggested that peroxidasin is secreted, and has functions related to the stabilization of the extracellular matrix. It may play a part in various other important processes such as removal and destruction of cells which have undergone programmed cell death and protection of the organism against non-self.

Pssm-ID: 143223 Cd Length: 69 Bit Score: 51.03 E-value: 7.89e-08

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 20127422  242 VELPCKALGHPEPDYRWLKDNMPLELSGRFQKTVTGLL-IENIRPSDSGSYVCEVSNRYGTAKV 304
Cdd:cd05746    1 VQIPCSAQGDPEPTITWNKDGVQVTESGKFHISPEGYLaIRDVGVADQGRYECVARNTIGYASV 64

Immunoglobulin (Ig)-like domain of myotilin, palladin, and myopalladin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the immunoglobulin (Ig)-like domain in myotilin, palladin, and myopalladin. Myotilin, palladin, and myopalladin function as scaffolds that regulate actin organization. Myotilin and myopalladin are most abundant in skeletal and cardiac muscle; palladin is ubiquitously expressed in the organs of developing vertebrates and plays a key role in cellular morphogenesis. The three family members each interact with specific molecular partners with all three binding to alpha-actinin; In addition, palladin also binds to vasodilator-stimulated phosphoprotein (VASP) and ezrin, myotilin binds to filamin and actin, and myopalladin also binds to nebulin and cardiac ankyrin repeat protein (CARP). This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409405 [Multi-domain] Cd Length: 91 Bit Score: 51.34 E-value: 1.03e-07

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  225 PSILDGFDHRKAMAGQRVELPCKALGHPEPDYRWLKDNMPLELSGRFQKTV--TG---LLIENIRPSDSGSYVCEVSNRY 299
Cdd:cd05744    1 PHFLQAPGDLEVQEGRLCRFDCKVSGLPTPDLFWQLNGKPVRPDSAHKMLVreNGrhsLIIEPVTKRDAGIYTCIARNRA 80

                         90
                 ....*....|.
gi 20127422  300 GTAKVIGRLYV 310
Cdd:cd05744   81 GENSFNAELVV 91

Immunoglobulin (Ig)-like ectodomain of the LRIG1 (Leucine-rich Repeats And Immunoglobulin-like Domains Protein 1) and similar proteins; member of the I-set of IgSF domains; The members here are composed of subgroup of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. The ectodomain of LRIG1 has two distinct regions: the proposed 15 LRRs and three Ig-like domains closer to the membrane. LRIG1 has been reported to interact with many receptor tyrosine kinases, GDNF/c-Ret, E-cadherin, JAK/STAT, c-Met, and the EGFR family signaling systems. Immunoglobulin Superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The structure of the LRIG1 extracellular Ig domain lacks a C" strand and thus is better described as a member of the I-set of IgSF domains.

Pssm-ID: 409420 [Multi-domain] Cd Length: 91 Bit Score: 51.47 E-value: 1.16e-07

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  692 FVVQPRDQDGIYGKAVILNCSAEGYPVPTIVWKFSKGAGVPQfqpiALNGRIQVLSNGSLL-IKHVVEEDSGYYLCKVSN 770
Cdd:cd05763    2 FTKTPHDITIRAGSTARLECAATGHPTPQIAWQKDGGTDFPA----ARERRMHVMPEDDVFfIVDVKIEDTGVYSCTAQN 77

                         90
                 ....*....|....
gi 20127422  771 DVGAdVSKSMYLTV 784
Cdd:cd05763   78 SAGS-ISANATLTV 90

Immunoglobulin-like domain of human Aortic Preferentially Expressed Protein-1 (APEG-1) and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin I-set (IgI) domain of the Human Aortic Preferentially Expressed Protein-1 (APEG-1) and similar proteins. APEG-1 is a novel specific smooth muscle differentiation marker predicted to play a role in the growth and differentiation of arterial smooth muscle cells (SMCs). The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the human APEG-1 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409567 Cd Length: 91 Bit Score: 51.32 E-value: 1.21e-07

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 20127422  801 QGQKKEMSCTAHGEKPIIVRWEKEDRIINPEMARYlvstKEVGEEVISTLQILPTVREDSGFFSCHAINSYG 872
Cdd:cd20975   14 EGQDVIMSIRVQGEPKPVVSWLRNRQPVRPDQRRF----AEEAEGGLCRLRILAAERGDAGFYTCKAVNEYG 81

First immunoglobulin (Ig) domain of contactin-1; member of the I-set of Ig superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-1. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409436 [Multi-domain] Cd Length: 95 Bit Score: 51.49 E-value: 1.23e-07

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 20127422  241 RVELPCKALGHPEPDYRWLKDNMPLELSGRFQKTVTG-LLIENIRPS-DSGSYVCEVSNRYGTAK 303
Cdd:cd05849   21 KVSVNCRARANPFPIYKWRKNNLDIDLTNDRYSMVGGnLVINNPDKYkDAGRYVCIVSNIYGKVR 85

Immunoglobulin domain; This domain contains immunoglobulin-like domains.

Pssm-ID: 464026 [Multi-domain] Cd Length: 79 Bit Score: 50.86 E-value: 1.23e-07

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 20127422    239 GQRVELPCKALGHPEPDYRWLKDNMPLELSGRFqktvtglLIENIRPSDSGSYVCEVSNRYG 300
Cdd:pfam13895   14 GEPVTLTCSAPGNPPPSYTWYKDGSAISSSPNF-------FTLSVSAEDSGTYTCVARNGRG 68

First immunoglobulin (Ig) domain of contactin; member of the I-set of (Ig) superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409356 [Multi-domain] Cd Length: 96 Bit Score: 51.48 E-value: 1.29e-07

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 20127422 1301 KDIVLPCKAVGDPSPAVKWMKdsNGTPSLVTIDGRRSIFSnGSFIIRT-VKAEDSGYYSCIANNNWGS 1367
Cdd:cd04967   20 KKVALNCRARANPVPSYRWLM--NGTEIDLESDYRYSLVD-GTLVISNpSKAKDAGHYQCLATNTVGS 84

Second C-terminal immunoglobulin (Ig)-like domain of palladin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the C-terminal immunoglobulin (Ig)-like domain of palladin. Palladin belongs to the palladin-myotilin-myopalladin family. Proteins belonging to this family contain multiple Ig-like domains and function as scaffolds, modulating actin cytoskeleton. Palladin binds to alpha-actinin ezrin, vasodilator-stimulated phosphoprotein VASP, SPIN90 (also known as DIP or mDia interacting protein), and Src. Palladin also binds F-actin directly, via its Ig3 domain. Palladin is expressed as several alternatively spliced isoforms, having various combinations of Ig-like domains, in a cell-type-specific manner. It has been suggested that palladin's different Ig-like domains may be specialized for distinct functions. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409582 Cd Length: 91 Bit Score: 50.87 E-value: 1.48e-07

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  407 PKIISAFSEKVVSPAEPVSLMCNVKGTPLPTITWTLDDDPILKGGSHRisqMITSEgNVVSYLNISSSQVRDGGVYRCTA 486
Cdd:cd20990    1 PHFLQAPGDLTVQEGKLCRMDCKVSGLPTPDLSWQLDGKPIRPDSAHK---MLVRE-NGVHSLIIEPVTSRDAGIYTCIA 76


                 ....*
gi 20127422  487 NNSAG 491
Cdd:cd20990   77 TNRAG 81

Second immunoglobulin (Ig)-like domain of the receptor protein tyrosine phosphatase (RPTP)-F; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain found in the receptor protein tyrosine phosphatase (RPTP)-F, also known as LAR. LAR belongs to the RPTP type IIa subfamily. Members of this subfamily are cell adhesion molecule-like proteins involved in central nervous system (CNS) development. They have large extracellular portions comprised of multiple Ig-like domains and two to nine fibronectin type III (FNIII) domains and a cytoplasmic portion having two tandem phosphatase domains.

Pssm-ID: 409400 [Multi-domain] Cd Length: 91 Bit Score: 51.17 E-value: 1.53e-07

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  416 KVVSPAEPVSLMCNVKGTPLPTITWTLDDDPI-LKGGSHRISQMITSEgnvvsyLNISSSQVRDGGVYRCTANNSAGvVL 494
Cdd:cd05738    9 KVVEKARTATMLCAASGNPDPEISWFKDFLPVdTATSNGRIKQLRSGA------LQIENSEESDQGKYECVATNSAG-TR 81


                 ....*..
gi 20127422  495 YQARINV 501
Cdd:cd05738   82 YSAPANL 88

immunoglobulin-like domain of telokin and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin (Ig) domain in telokin, the C-terminal domain of myosin light chain kinase which is identical to telokin, and similar proteins. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the telokin Ig domain lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409565 [Multi-domain] Cd Length: 88 Bit Score: 51.04 E-value: 1.53e-07

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 20127422  239 GQRVELPCKALGHPEPDYRWLKDNMPLELSGRFQKTVTG-----LLIENIRPSDSGSYVCEVSNRYGTAKVIGRLYV 310
Cdd:cd20973   12 GSAARFDCKVEGYPDPEVKWMKDDNPIVESRRFQIDQDEdglcsLIISDVCGDDSGKYTCKAVNSLGEATCSAELTV 88

Sixth immunoglobulin (Ig) domain of contactin-2; The members here are composed of the sixth immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-2-like. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-2 (TAG-1, axonin-1) facilitates cell adhesion by homophilic binding between molecules in apposed membranes. It may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module by contacts between IG domains 1 and 4, and domains 2 and 3. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-2 is also expressed in retinal amacrine cells (AC) in the developing chick retina, corresponding to the period of formation and maturation of AC processes.

Pssm-ID: 409440 Cd Length: 102 Bit Score: 51.20 E-value: 1.68e-07

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  404 DGTpKIISAFSEKVVSPAEPVSLMCNVKGTPLP--TITWTLDDDPI---LKGGSHRISQMITSEGNVVsylnISSSQVRD 478
Cdd:cd05854    1 DAT-KITLAPSSADINQGENLTLQCHASHDPTMdlTFTWSLDDFPIdldKPNGHYRRMEVKETIGDLV----IVNAQLSH 75

                         90       100
                 ....*....|....*....|....*.
gi 20127422  479 GGVYRCTANNSAGVVLYQARINVRGP 504
Cdd:cd05854   76 AGTYTCTAQTVVDSASASATLVVRGP 101

Second Ig-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the titin Z1z2 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409564 [Multi-domain] Cd Length: 91 Bit Score: 50.66 E-value: 1.85e-07

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  224 APSILDGFDHRKAMAGQRVELPCKALGHPEPDYRWLKDNMPLELSGRFQKTVTG----LLIENIRPSDSGSYVCEVSNRY 299
Cdd:cd20972    1 PPQFIQKLRSQEVAEGSKVRLECRVTGNPTPVVRWFCEGKELQNSPDIQIHQEGdlhsLIIAEAFEEDTGRYSCLATNSV 80

                         90
                 ....*....|.
gi 20127422  300 GTAKVIGRLYV 310
Cdd:cd20972   81 GSDTTSAEIFV 91

First immunoglobulin (Ig) domain of contactin-5; member of the I-set of Ig superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-5. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains, anchored to the membrane by glycosylphosphatidylinositol. The different contactins show different expression patterns in the central nervous system. In rats, a lack of contactin-5 (NB-2) results in an impairment of the neuronal activity in the auditory system. Contactin-5 is expressed specifically in the postnatal nervous system, peaking at about 3 weeks postnatal. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala; lower levels of expression have been detected in the corpus callosum, caudate nucleus, and spinal cord. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409435 Cd Length: 96 Bit Score: 50.71 E-value: 1.86e-07

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 20127422 1301 KDIVLPCKAVGDPSPAVKWMKdsNGTPSLVTIDGRRSIFsNGSFIIRTV-KAEDSGYYSCIANNNWGS 1367
Cdd:cd05848   20 KKVILNCEARGNPVPTYRWLR--NGTEIDTESDYRYSLI-DGNLIISNPsEVKDSGRYQCLATNSIGS 84

Third immunoglobulin (Ig) domain of contactin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409357 [Multi-domain] Cd Length: 88 Bit Score: 50.62 E-value: 1.87e-07

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  689 PPKFVVQPRDQDGIYGKAVILNCSAEGYPVPTIVWKFSKGAGVPQfqpialngRIQVLSNGSLLIKHVVEEDSGYYLCKV 768
Cdd:cd04968    1 PSIKVRFPADTYALKGQTVTLECFALGNPVPQIKWRKVDGSPSSQ--------WEITTSEPVLEIPNVQFEDEGTYECEA 72


                 ....*..
gi 20127422  769 SNDVGAD 775
Cdd:cd04968   73 ENSRGKD 79

agrin-responsive first immunoglobulin-like domains (Ig1) of the MuSK ectodomain; a member of the I-set of IgSF domains; The members here are composed of the first immunoglobulin-like domains (Ig1) of the Muscle-specific kinase (MuSK). MuSK is a receptor tyrosine kinase specifically expressed in skeletal muscle, where it plays a central role in the formation and maintenance of the neuromuscular junction (NMJ). MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. The activation of MUSK in myotubes regulates the formation of NMJs through the regulation of different processes including the specific expression of genes in subsynaptic nuclei, the reorganization of the actin cytoskeleton and the clustering of the acetylcholine receptors (AChR) in the postsynaptic membrane. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the MuSK lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409562 [Multi-domain] Cd Length: 92 Bit Score: 50.58 E-value: 1.89e-07

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 20127422  414 SEKVVSPAEPVSLMCNVKGTPLPTITWTLDDDPILKGGSHRIsqmITSEGNVVSYLNISSSqvrDGGVYRCTANNSAG 491
Cdd:cd20970   10 FTVTAREGENATFMCRAEGSPEPEISWTRNGNLIIEFNTRYI---VRENGTTLTIRNIRRS---DMGIYLCIASNGVP 81

Third immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule 1 (NCAM-1); member of the I-set of IgSF domains; The members here are composed of the third immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule (NCAM-1). NCAM plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM), and heterophilic (NCAM-non-NCAM), interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves Ig1, Ig2, and Ig3. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions) through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain.

Pssm-ID: 143207 [Multi-domain] Cd Length: 95 Bit Score: 50.70 E-value: 1.90e-07

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 20127422 1303 IVLPCKAVGDPSPAVKWMKDsnGTPsLVTIDGRRSIFSNGS-FIIRTVKAEDSGYYSCIANNNWGSDEIILNLQV 1376
Cdd:cd05730   21 VTLACDADGFPEPTMTWTKD--GEP-IESGEEKYSFNEDGSeMTILDVDKLDEAEYTCIAENKAGEQEAEIHLKV 92

Immunoglobulin domain; The members here are composed of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. Members of this group are components of immunoglobulin, neuroglia, cell surface glycoproteins, including T-cell receptors, CD2, CD4, CD8, and membrane glycoproteins, including butyrophilin and chondroitin sulfate proteoglycan core protein. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. Ig superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Typically, the V-set domains have A, B, E, and D strands in one sheet and A', G, F, C, C' and C" in the other. The structures in C1-set are smaller than those in the V-set; they have one beta sheet that is formed by strands A, B, E, and D and the other by strands G, F, C, and C'. Moreover, a C1-set Ig domain contains a short C' strand (three residues) and lacks A' and C" strand. Unlike other Ig domain sets, C2-set structures do not have a D strand. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409353 [Multi-domain] Cd Length: 70 Bit Score: 49.64 E-value: 2.30e-07

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 20127422  806 EMSCTAHGEKPIIVRWEKEDRIINPEMarylvSTKEVGEEVISTLQILPTVREDSGFFSCHAINSYGE 873
Cdd:cd00096    2 TLTCSASGNPPPTITWYKNGKPLPPSS-----RDSRRSELGNGTLTISNVTLEDSGTYTCVASNSAGG 64

Immunoglobulin (Ig)-like domain of the human basement membrane heparan sulfate proteoglycan perlecan and similar proteins; The members here are composed of the immunoglobulin (Ig)-like domain of the human basement membrane heparan sulfate proteoglycan perlecan, also known as HSPG2, and similar proteins. Perlecan consists of five domains: domain I has three putative heparan sulfate attachment sites, domain II has four LDL receptor-like repeats, and one Ig-like repeat, domain III resembles the short arm of laminin chains, domain IV has multiple Ig-like repeats (21 repeats in human perlecan), and domain V resembles the globular G domain of the laminin A chain and internal repeats of EGF. Perlecan may participate in a variety of biological functions including cell binding, LDL-metabolism, basement membrane assembly and selective permeability, calcium binding, and growth- and neurite-promoting activities.

Pssm-ID: 143220 Cd Length: 78 Bit Score: 49.80 E-value: 2.46e-07

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 20127422  239 GQRVELPCKALGHPEPDYRWLKDNMPLELSGRFQKTVTG----LLIENIRPSDSGSYVCEVSNRYGTAKVI 305
Cdd:cd05743    1 GETVEFTCVATGVPTPIINWRLNWGHVPDSARVSITSEGgygtLTIRDVKESDQGAYTCEAINTRGMVFGI 71

Immunoglobulin I-set domain;

Pssm-ID: 400151 [Multi-domain] Cd Length: 90 Bit Score: 50.33 E-value: 2.66e-07

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422    802 GQKKEMSCTAHGEKPIIVRWEKEDRIINPEmARYLVSTkevgEEVISTLQILPTVREDSGFFSCHAINSYGEDRGIIQLT 881
Cdd:pfam07679   15 GESARFTCTVTGTPDPEVSWFKDGQPLRSS-DRFKVTY----EGGTYTLTISNVQPDDSGKYTCVATNSAGEAEASAELT 89


                   .
gi 20127422    882 V 882
Cdd:pfam07679   90 V 90

First immunoglobulin (Ig)-like constant domain in Robo (roundabout) receptors, and similar domains; The members here are composed of the first immunoglobulin (Ig)-like domain in Roundabout (Robo) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit1, Slit2, Slit3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit1, Slit2,and Slit3 are expressed at the ventral midline. Robo3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be is the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site.

Pssm-ID: 409490 [Multi-domain] Cd Length: 99 Bit Score: 50.63 E-value: 2.69e-07

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  690 PKFVVQPRDQDGIYGKAVILNCSAEGYPVPTIVWkFSKGAGVPQFQPIALNGRIqVLSNGSLLIKHVV-----EEDSGYY 764
Cdd:cd07693    1 PRIVEHPSDLIVSKGDPATLNCKAEGRPTPTIQW-LKNGQPLETDKDDPRSHRI-VLPSGSLFFLRVVhgrkgRSDEGVY 78

                         90       100
                 ....*....|....*....|
gi 20127422  765 LCKVSNDVGADVSKSMYLTV 784
Cdd:cd07693   79 VCVAHNSLGEAVSRNASLEV 98

Fourth immunoglobulin (Ig)-like domain of hemolin, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain of hemolin and similar proteins. Hemolin, an insect immunoglobulin superfamily (IgSF) member containing four Ig-like domains, is a lipopolysaccharide-binding immune protein induced during bacterial infection. Hemolin shares significant sequence similarity with the first four Ig-like domains of the transmembrane cell adhesion molecules (CAMs) of the L1 family. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The fourth Ig-like domain of hemolin is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409570 [Multi-domain] Cd Length: 88 Bit Score: 50.08 E-value: 2.88e-07

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 20127422  509 PMKNITAIAGRDTYIHCRVIGYPYYSIKWYKNSNLLPFNHRQVAFEnNGTLKLSDVQKEvDEGEYTCN 576
Cdd:cd20978    7 PEKNVVVKGGQDVTLPCQVTGVPQPKITWLHNGKPLQGPMERATVE-DGTLTIINVQPE-DTGYYGCV 72

Seventh immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the seventh immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409546 [Multi-domain] Cd Length: 96 Bit Score: 50.39 E-value: 3.00e-07

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 20127422  511 KNITAIAGRDTYIHCRVIGYPYYSIKWYKNSNLLPFNHRQVAFEN------NGTLKLSDVQKEvDEGEYTC 575
Cdd:cd20954    9 VDANVAAGQDVMLHCQADGFPTPTVTWKKATGSTPGEYKDLLYDPnvrilpNGTLVFGHVQKE-NEGHYLC 78

Immunoglobulin (Ig)-like ectodomain of the LRIG1 (Leucine-rich Repeats And Immunoglobulin-like Domains Protein 1) and similar proteins; member of the I-set of IgSF domains; The members here are composed of subgroup of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. The ectodomain of LRIG1 has two distinct regions: the proposed 15 LRRs and three Ig-like domains closer to the membrane. LRIG1 has been reported to interact with many receptor tyrosine kinases, GDNF/c-Ret, E-cadherin, JAK/STAT, c-Met, and the EGFR family signaling systems. Immunoglobulin Superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The structure of the LRIG1 extracellular Ig domain lacks a C" strand and thus is better described as a member of the I-set of IgSF domains.

Pssm-ID: 409420 [Multi-domain] Cd Length: 91 Bit Score: 50.31 E-value: 3.02e-07

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 20127422 1305 LPCKAVGDPSPAVKWMKDSnGTPSLVTIDGRRSIFSNGS-FIIRTVKAEDSGYYSCIANNNWGS 1367
Cdd:cd05763   19 LECAATGHPTPQIAWQKDG-GTDFPAARERRMHVMPEDDvFFIVDVKIEDTGVYSCTAQNSAGS 81

Immunoglobulin domain; Members of the immunoglobulin superfamily are found in hundreds of proteins of different functions. Examples include antibodies, the giant muscle kinase titin and receptor tyrosine kinases. Immunoglobulin-like domains may be involved in protein-protein and protein-ligand interactions.

Pssm-ID: 395002 Cd Length: 86 Bit Score: 49.89 E-value: 3.09e-07

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 20127422    607 FSIGQRVFIPCVVVSGDLPITITWQKDG-RPIPGSLGVTIDNIDFTSSLRISNLSLMHNGNYTCIARN 673
Cdd:pfam00047    8 VLEGDSATLTCSASTGSPGPDVTWSKEGgTLIESLKVKHDNGRTTQSSLLISNVTKEDAGTYTCVVNN 75

Second immunoglobulin (Ig)-like domain of a Follistatin-related protein 5, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain found in human Follistatin-related protein 5 (FSTL5) and a follistatin-like molecule encoded by the CNS-related Mahya gene. Mahya genes have been retained in certain Bilaterian branches during evolution. They are conserved in Hymenoptera and Deuterostomes, but are absent from other metazoan species such as fruit fly and nematode. Mahya proteins are secretory, with a follistatin-like domain (Kazal-type serine/threonine protease inhibitor domain and EF-hand calcium-binding domain), two Ig-like domains, and a novel C-terminal domain. Mahya may be involved in learning and memory and in processing of sensory information in Hymenoptera and vertebrates. Follistatin is a secreted, multidomain protein that binds activins with high affinity and antagonizes their signaling.

Pssm-ID: 409399 [Multi-domain] Cd Length: 93 Bit Score: 49.95 E-value: 3.41e-07

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 20127422  420 PAEPVSLMCNVKGTPLPTITWTLDDDPIlkggSHRISQMITSEGNvVSYLNISSSQVRDGGVYRCTANNSAGV 492
Cdd:cd05736   14 PGVEASLRCHAEGIPLPRVQWLKNGMDI----NPKLSKQLTLIAN-GSELHISNVRYEDTGAYTCIAKNEGGV 81

Immunoglobulin (Ig)-like I-set domain of Neural Cell Adhesion Molecule 1 (NCAM-1) and similar proteins; The members here are composed of the fourth immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule (NCAM-1). NCAM plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM), and heterophilic (NCAM-non-NCAM), interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves Ig1, Ig2, and Ig3. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions), through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain. Also included in this group is NCAM-2 (also known as OCAM/mamFas II and RNCAM) NCAM-2 is differentially expressed in the developing and mature olfactory epithelium (OE). One of the unique features of I-set domains is the lack of a C" strand. The structures of this group show that the Ig domain lacks this strand and thus is a member of the I-set of Ig domains.

Pssm-ID: 409395 [Multi-domain] Cd Length: 96 Bit Score: 50.22 E-value: 3.47e-07

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1289 LTFSGTVTTPWMKDIVLPCKAVGDPSPAVKWMKDSNG-TPSLVTIDGR---RSIFSNGSFIIRTVKAEDSGYYSCIANNN 1364
Cdd:cd05732    5 ITYLENQTAVELEQITLTCEAEGDPIPEITWRRATRGiSFEEGDLDGRivvRGHARVSSLTLKDVQLTDAGRYDCEASNR 84

                         90
                 ....*....|..
gi 20127422 1365 WGSDEIILNLQV 1376
Cdd:cd05732   85 IGGDQQSMYLEV 96

Immunoglobulin domain I1 of the titin I-band and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin domain I1 of the titin I-band and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. The two sheets are linked together by a conserved disulfide bond between B strand and F strand. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The Ig I1 domain of the titin I-band is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409543 [Multi-domain] Cd Length: 94 Bit Score: 50.11 E-value: 3.57e-07

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  407 PKIISAFSEKVVSPAEPVSLMCNVKGTPLPTITWTLDDDPILKGGSHRISQmITSEGNvVSYLNISSSQVRDGGVYRCTA 486
Cdd:cd20951    1 PEFIIRLQSHTVWEKSDAKLRVEVQGKPDPEVKWYKNGVPIDPSSIPGKYK-IESEYG-VHVLHIRRVTVEDSAVYSAVA 78

                         90
                 ....*....|....*.
gi 20127422  487 NNSAGVVLYQARINVR 502
Cdd:cd20951   79 KNIHGEASSSASVVVE 94

Immunoglobulin domain; The members here are composed of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. Members of this group are components of immunoglobulin, neuroglia, cell surface glycoproteins, including T-cell receptors, CD2, CD4, CD8, and membrane glycoproteins, including butyrophilin and chondroitin sulfate proteoglycan core protein. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. Ig superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Typically, the V-set domains have A, B, E, and D strands in one sheet and A', G, F, C, C' and C" in the other. The structures in C1-set are smaller than those in the V-set; they have one beta sheet that is formed by strands A, B, E, and D and the other by strands G, F, C, and C'. Moreover, a C1-set Ig domain contains a short C' strand (three residues) and lacks A' and C" strand. Unlike other Ig domain sets, C2-set structures do not have a D strand. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409353 [Multi-domain] Cd Length: 70 Bit Score: 49.25 E-value: 3.58e-07

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*....
gi 20127422  331 VSLSCSVTGTEDQELSWYRNGEILNPGKNVRITGINHE-NLIMDHMVKSDGGAYQCFVR 388
Cdd:cd00096    1 VTLTCSASGNPPPTITWYKNGKPLPPSSRDSRRSELGNgTLTISNVTLEDSGTYTCVAS 59

Third immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule 1 (NCAM-1); member of the I-set of IgSF domains; The members here are composed of the third immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule (NCAM-1). NCAM plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM), and heterophilic (NCAM-non-NCAM), interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves Ig1, Ig2, and Ig3. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions) through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain.

Pssm-ID: 143207 [Multi-domain] Cd Length: 95 Bit Score: 49.55 E-value: 4.89e-07

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 20127422  236 AMAGQRVELPCKALGHPEPDYRWLKDNMPLElSGR----FQKTVTGLLIENIRPSDSGSYVCEVSNRYGTAKVIGRLYV 310
Cdd:cd05730   15 ANLGQSVTLACDADGFPEPTMTWTKDGEPIE-SGEekysFNEDGSEMTILDVDKLDEAEYTCIAENKAGEQEAEIHLKV 92

immunoglobulin-like domain of telokin and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin (Ig) domain in telokin, the C-terminal domain of myosin light chain kinase which is identical to telokin, and similar proteins. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the telokin Ig domain lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409565 [Multi-domain] Cd Length: 88 Bit Score: 49.50 E-value: 5.13e-07

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  410 ISAFSEKVVSPAEPVSLMCNVKGTPLPTITWTLDDDPILKggSHRISqmITSEGNVVSYLNISSSQVRDGGVYRCTANNS 489
Cdd:cd20973    1 IQTLRDKEVVEGSAARFDCKVEGYPDPEVKWMKDDNPIVE--SRRFQ--IDQDEDGLCSLIISDVCGDDSGKYTCKAVNS 76


                 ..
gi 20127422  490 AG 491
Cdd:cd20973   77 LG 78

C-terminal immunoglobulin (Ig)-like domain of M-protein; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the C-terminal immunoglobulin (Ig)-like domain of M-protein (also known as myomesin-2). M-protein is a structural protein localized to the M-band, a transverse structure in the center of the sarcomere, and is a candidate for M-band bridges. M-protein is modular consisting mainly of repetitive IG-like and fibronectin type III (FnIII) domains and has a muscle-type specific expression pattern. M-protein is present in fast fibers.

Pssm-ID: 143299 Cd Length: 92 Bit Score: 49.52 E-value: 5.32e-07

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 20127422  237 MAGQRVELPCKALGHPEPDYRWLKDNMPLELSGRF-----QKTVTGLLIENIRPSDSGSYVCEVSNRYGTAKV 304
Cdd:cd05891   14 MEGKTLNLTCTVFGNPDPEVIWFKNDQDIELSEHYsvkleQGKYASLTIKGVTSEDSGKYSINVKNKYGGETV 86

Immunoglobulin (Ig)-like domain of human titin C terminus and similar proteins; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the fifth immunoglobulin (Ig)-like domain from the C-terminus of human titin x and similar proteins. Titin (also called connectin) is a fibrous sarcomeric protein specifically found in vertebrate striated muscle. Titin is gigantic; depending on isoform composition it ranges from 2970 to 3700 kDa, and is of a length that spans half a sarcomere. Titin largely consists of multiple repeats of Ig-like and fibronectin type 3 (FN-III)-like domains. Titin connects the ends of myosin thick filaments to Z disks and extends along the thick filament to the H zone and appears to function similar to an elastic band, keeping the myosin filaments centered in the sarcomere during muscle contraction or stretching. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 143224 [Multi-domain] Cd Length: 92 Bit Score: 49.28 E-value: 5.87e-07

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 20127422  418 VSPAEPVSLMCNVKGTPLPTITWTLDDDPILKGGSHRISQMitsegNVVSYLNISSSQVRDGGVYRCTANNSAG 491
Cdd:cd05747   15 VSEGESARFSCDVDGEPAPTVTWMREGQIIVSSQRHQITST-----EYKSTFEISKVQMSDEGNYTVVVENSEG 83

Immunoglobulin domain; This domain contains immunoglobulin-like domains.

Pssm-ID: 464026 [Multi-domain] Cd Length: 79 Bit Score: 48.93 E-value: 6.32e-07

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 20127422    597 PFIQPfEFPRFSIGQRVFIPCVVvSGDLPITITWQKDGRPIPGSlgvtidnidftSSLRISNLSLMHNGNYTCIARN 673
Cdd:pfam13895    2 PVLTP-SPTVVTEGEPVTLTCSA-PGNPPPSYTWYKDGSAISSS-----------PNFFTLSVSAEDSGTYTCVARN 65

Third immunoglobulin (Ig) domain of contactin-1; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-1. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-1 is differentially expressed in tumor tissues and may through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 143259 Cd Length: 88 Bit Score: 49.25 E-value: 6.43e-07

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  406 TPKIISAFSEKVVSPAEPVSLMCNVKGTPLPTITWTLDDDPILKggshriSQMITSEGNVVSYLNIsssQVRDGGVYRCT 485
Cdd:cd05851    1 PADINVKFKDTYALKGQNVTLECFALGNPVPVIRWRKILEPMPA------TAEISMSGAVLKIFNI---QPEDEGTYECE 71

                         90
                 ....*....|....*..
gi 20127422  486 ANNSAGVVLYQARINVR 502
Cdd:cd05851   72 AENIKGKDKHQARVYVQ 88

Fifth immunoglobulin (Ig) domain of contactin; The members here are composed of the fifth immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409358 [Multi-domain] Cd Length: 89 Bit Score: 49.00 E-value: 7.21e-07

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 20127422  509 PMKNITAIA-GRDTYIHCRVIGYPYYSIKWYKNSNLLPFNHRqVAFENNGTLKLSDVQKEvDEGEYTC 575
Cdd:cd04969    7 PVKKKILAAkGGDVIIECKPKASPKPTISWSKGTELLTNSSR-ICILPDGSLKIKNVTKS-DEGKYTC 72

Fifth Ig-like domain of Roundabout (Robo) homolog 1/2, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fifth Ig-like domain of Roundabout (Robo) homolog 1/2 and similar domains. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, -2, and -3), and three mammalian Slit homologs (Slit-1,-2, -3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, -2, and -3 are expressed by commissural neurons in the vertebrate spinal cord and Slits 1, -2, -3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of slit responsiveness, antagonizes slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be is the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. The fifth Ig-like domain of Robo 1 and 2 is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors

Pssm-ID: 409544 [Multi-domain] Cd Length: 87 Bit Score: 48.65 E-value: 7.65e-07

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  415 EKVVSPAEPVSLMCNVKGTPLPTITWTLDDDPILKGGSHrisqmITSEGNVVsyLNISSSQVRDGGVYRCTANNSAGVVL 494
Cdd:cd20952    8 NQTVAVGGTVVLNCQATGEPVPTISWLKDGVPLLGKDER-----ITTLENGS--LQIKGAEKSDTGEYTCVALNLSGEAT 80


                 ....*..
gi 20127422  495 YQARINV 501
Cdd:cd20952   81 WSAVLDV 87

Third immunoglobulin (Ig)-like domain of peroxidasin; The members here are composed of the third immunoglobulin (Ig)-like domain in peroxidasin. Peroxidasin has a peroxidase domain and interacting extracellular motifs containing four Ig-like domains. It has been suggested that peroxidasin is secreted and has functions related to the stabilization of the extracellular matrix. It may play a part in various other important processes such as removal and destruction of cells which have undergone programmed cell death and protection of the organism against non-self.

Pssm-ID: 143222 [Multi-domain] Cd Length: 74 Bit Score: 48.40 E-value: 7.82e-07

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 20127422  239 GQRVELPCKALGHPEPDYRWLKDNMPLELSGRFQKTVTGLL-IENIRPSDSGSYVCEVSNRYGTAKVIGRLYV 310
Cdd:cd05745    2 GQTVDFLCEAQGYPQPVIAWTKGGSQLSVDRRHLVLSSGTLrISRVALHDQGQYECQAVNIVGSQRTVAQLTV 74

agrin-responsive first immunoglobulin-like domains (Ig1) of the MuSK ectodomain; a member of the I-set of IgSF domains; The members here are composed of the first immunoglobulin-like domains (Ig1) of the Muscle-specific kinase (MuSK). MuSK is a receptor tyrosine kinase specifically expressed in skeletal muscle, where it plays a central role in the formation and maintenance of the neuromuscular junction (NMJ). MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. The activation of MUSK in myotubes regulates the formation of NMJs through the regulation of different processes including the specific expression of genes in subsynaptic nuclei, the reorganization of the actin cytoskeleton and the clustering of the acetylcholine receptors (AChR) in the postsynaptic membrane. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the MuSK lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409562 [Multi-domain] Cd Length: 92 Bit Score: 49.04 E-value: 7.84e-07

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  217 VSDPANSAPSIldgfdhrkAMAGQRVELPCKALGHPEPDYRWL-KDNMPLELSGRFQKTVTG--LLIENIRPSDSGSYVC 293
Cdd:cd20970    3 ISTPQPSFTVT--------AREGENATFMCRAEGSPEPEISWTrNGNLIIEFNTRYIVRENGttLTIRNIRRSDMGIYLC 74


                 ....
gi 20127422  294 EVSN 297
Cdd:cd20970   75 IASN 78

Eighth immunoglobulin (Ig)-like domain of human myosin light-chain kinase (MLCK) and similar protein; member of the I-set of IgSF domains; The members here are composed of the eighth immunoglobulin (Ig)-like domain of human myosin light-chain kinase (MLCK) and similar proteins. Myosin light-chain kinase (MLCK) is a key regulator of different forms of cell motility involving actin and myosin II. Agonist stimulation of smooth muscle cells increases cytosolic Ca2+ which binds calmodulin. This Ca2+-calmodulin complex in turn binds to and activates MLCK. Activated MLCK leads to the phosphorylation of the 20 kDa myosin regulatory light chain (RLC) of myosin II and the stimulation of actin-activated myosin MgATPase activity. MLCK is widely present in vertebrate tissues; it phosphorylates the 20 kDa RLC of both smooth and nonmuscle myosin II. Phosphorylation leads to the activation of the myosin motor domain and altered structural properties of myosin II. In smooth muscle MLCK it is involved in initiating contraction. In nonmuscle cells, MLCK may participate in cell division and cell motility; it has been suggested MLCK plays a role in cardiomyocyte differentiation and contraction through regulation of nonmuscle myosin II.

Pssm-ID: 409419 Cd Length: 99 Bit Score: 48.80 E-value: 9.39e-07

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  596 PPFIQPF-EFPRFSIGQRVFIPCVVVsGDLPITITWQKDGRPIPGSLGVTIDNIDFTSSLRISNLSLMHNGNYTCIARNE 674
Cdd:cd05762    1 PPQIIQFpEDMKVRAGESVELFCKVT-GTQPITCTWMKFRKQIQEGEGIKIENTENSSKLTITEGQQEHCGCYTLEVENK 79

                         90
                 ....*....|..
gi 20127422  675 AAAVEHQSQLIV 686
Cdd:cd05762   80 LGSRQAQVNLTV 91

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor, and similar domains; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor. FGF receptors bind FGF signaling polypeptides. FGFs participate in multiple processes such as morphogenesis, development, and angiogenesis. FGFs bind to four FGF receptor tyrosine kinases (FGFR1, FGFR2, FGFR3, FGFR4). Receptor diversity is controlled by alternative splicing producing splice variants with different ligand binding characteristics and different expression patterns. FGFRs have an extracellular region comprised of three Ig-like domains, a single transmembrane helix, and an intracellular tyrosine kinase domain. Ligand binding and specificity reside in the Ig-like domains 2 and 3, and the linker region that connects these two. FGFR activation and signaling depend on FGF-induced dimerization, a process involving cell surface heparin or heparin sulfate proteoglycans. This group also contains fibroblast growth factor (FGF) receptor like-1(FGFRL1). FGFRL1 does not have a protein tyrosine kinase domain at its C-terminus; neither does its cytoplasmic domain appear to interact with a signaling partner. It has been suggested that FGFRL1 may not have any direct signaling function, but instead acts as a decoy receptor trapping FGFs and preventing them from binding other receptors.

Pssm-ID: 409393 [Multi-domain] Cd Length: 95 Bit Score: 48.76 E-value: 9.91e-07

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 20127422 1303 IVLPCKAVGDPSPAVKWMKDSNGTPSLVTIDGRRSIFSNGSFIIRTVKAEDSGYYSCIANNNWGSDEIILNLQV 1376
Cdd:cd05729   22 VRLECGAGGNPMPNITWLKDGKEFKKEHRIGGTKVEEKGWSLIIERAIPRDKGKYTCIVENEYGSINHTYDVDV 95

Third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM), and similar domains; The members here are composed of the third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, and spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM and human neurofascin.

Pssm-ID: 409394 [Multi-domain] Cd Length: 83 Bit Score: 48.17 E-value: 1.04e-06

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  509 PMKNITAIAGRDTYIHCRVIGYPYYSIKWYKNSNLLPFNHRQvaFEN-NGTLKLSDVQKEvDEGEYTCnVLVQPQLSTSQ 587
Cdd:cd05731    1 SESSTMVLRGGVLLLECIAEGLPTPDIRWIKLGGELPKGRTK--FENfNKTLKIENVSEA-DSGEYQC-TASNTMGSARH 76


                 ....*..
gi 20127422  588 SVHVTVK 594
Cdd:cd05731   77 TISVTVE 83

Immunoglobulin (Ig)-like domain of myotilin, palladin, and myopalladin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the immunoglobulin (Ig)-like domain in myotilin, palladin, and myopalladin. Myotilin, palladin, and myopalladin function as scaffolds that regulate actin organization. Myotilin and myopalladin are most abundant in skeletal and cardiac muscle; palladin is ubiquitously expressed in the organs of developing vertebrates and plays a key role in cellular morphogenesis. The three family members each interact with specific molecular partners with all three binding to alpha-actinin; In addition, palladin also binds to vasodilator-stimulated phosphoprotein (VASP) and ezrin, myotilin binds to filamin and actin, and myopalladin also binds to nebulin and cardiac ankyrin repeat protein (CARP). This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409405 [Multi-domain] Cd Length: 91 Bit Score: 48.65 E-value: 1.09e-06

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  690 PKFVVQPRDQDGIYGKAVILNCSAEGYPVPTIVWKFSKgagvpqfQPIALNGRIQVLSNG----SLLIKHVVEEDSGYYL 765
Cdd:cd05744    1 PHFLQAPGDLEVQEGRLCRFDCKVSGLPTPDLFWQLNG-------KPVRPDSAHKMLVREngrhSLIIEPVTKRDAGIYT 73


                 ....*...
gi 20127422  766 CKVSNDVG 773
Cdd:cd05744   74 CIARNRAG 81

Fibronectin type 3 domain; One of three types of internal repeat within the plasma protein, fibronectin. The tenth fibronectin type III repeat contains a RGD cell recognition sequence in a flexible loop between 2 strands. Type III modules are present in both extracellular and intracellular proteins.

Pssm-ID: 214495 [Multi-domain] Cd Length: 83 Bit Score: 48.38 E-value: 1.13e-06

                            10        20        30        40        50        60        70        80
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422    1189 PGPPAGVKAAAASASMVFVSWLPPLKLNGiiRKYTVFCSHPYPTVISEFE---ASPDSFSYRIPNLSRNRQYSVWVVAVT 1265
Cdd:smart00060    1 PSPPSNLRVTDVTSTSVTLSWEPPPDDGI--TGYIVGYRVEYREEGSEWKevnVTPSSTSYTLTGLKPGTEYEFRVRAVN 78


                    ....*
gi 20127422    1266 SAGRG 1270
Cdd:smart00060   79 GAGEG 83

First immunoglobulin (Ig) domain of contactin; member of the I-set of (Ig) superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409356 [Multi-domain] Cd Length: 96 Bit Score: 48.78 E-value: 1.15e-06

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 20127422  240 QRVELPCKALGHPEPDYRWLKDN--MPLELSGRFQKTVTGLLIEN-IRPSDSGSYVCEVSNRYGT 301
Cdd:cd04967   20 KKVALNCRARANPVPSYRWLMNGteIDLESDYRYSLVDGTLVISNpSKAKDAGHYQCLATNTVGS 84

Third immunoglobulin (Ig)-like domain of peroxidasin; The members here are composed of the third immunoglobulin (Ig)-like domain in peroxidasin. Peroxidasin has a peroxidase domain and interacting extracellular motifs containing four Ig-like domains. It has been suggested that peroxidasin is secreted and has functions related to the stabilization of the extracellular matrix. It may play a part in various other important processes such as removal and destruction of cells which have undergone programmed cell death and protection of the organism against non-self.

Pssm-ID: 143222 [Multi-domain] Cd Length: 74 Bit Score: 48.01 E-value: 1.17e-06

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 20127422 1305 LPCKAVGDPSPAVKWMKDSNGTPslvtIDGRRSIFSNGSFIIRTVKAEDSGYYSCIANNNWGSDEIILNLQV 1376
Cdd:cd05745    7 FLCEAQGYPQPVIAWTKGGSQLS----VDRRHLVLSSGTLRISRVALHDQGQYECQAVNIVGSQRTVAQLTV 74

Second immunoglobulin (Ig)-like domain of a Follistatin-related protein 5, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain found in human Follistatin-related protein 5 (FSTL5) and a follistatin-like molecule encoded by the CNS-related Mahya gene. Mahya genes have been retained in certain Bilaterian branches during evolution. They are conserved in Hymenoptera and Deuterostomes, but are absent from other metazoan species such as fruit fly and nematode. Mahya proteins are secretory, with a follistatin-like domain (Kazal-type serine/threonine protease inhibitor domain and EF-hand calcium-binding domain), two Ig-like domains, and a novel C-terminal domain. Mahya may be involved in learning and memory and in processing of sensory information in Hymenoptera and vertebrates. Follistatin is a secreted, multidomain protein that binds activins with high affinity and antagonizes their signaling.

Pssm-ID: 409399 [Multi-domain] Cd Length: 93 Bit Score: 48.41 E-value: 1.34e-06

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  690 PKFVVQPRDQDGIYGKAVILNCSAEGYPVPTIVWkFSKGAGVPQFQPIALNgriqVLSNGS-LLIKHVVEEDSGYYLCKV 768
Cdd:cd05736    1 PVIRVYPEFQAKEPGVEASLRCHAEGIPLPRVQW-LKNGMDINPKLSKQLT----LIANGSeLHISNVRYEDTGAYTCIA 75


                 ....*..
gi 20127422  769 SNDVGAD 775
Cdd:cd05736   76 KNEGGVD 82

C-terminal immunoglobulin-like domain of the myosin-associated giant protein kinase Twitchin, and similar domains; member of the I-set IgSF domains; The members here are composed of the C-terminal immunoglobulin-like domain of the myosin-associated giant protein kinase Twitchin and similar proteins, including Caenorhabditis elegans and Aplysia californica Twitchin, Drosophila melanogaster Projectin, and similar proteins. These are very large muscle proteins containing multiple immunoglobulin (Ig)-like and fibronectin type III (FN3) domains and a single kinase domain near the C-terminus. In humans these proteins are called Titin. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The Ig-like domain of the Twitchin is a member of the I-set IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins (titin, telokin, and twitchin), the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D.

Pssm-ID: 409541 [Multi-domain] Cd Length: 89 Bit Score: 48.10 E-value: 1.36e-06

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 20127422  239 GQRVELPCKALGHPEPDYRWLKDNMPLELS----GRFQKTVTGLLIENIRPSDSGSYVCEVSNRYGTAKVIGRLYV 310
Cdd:cd20949   14 GQSATILCEVKGEPQPNVTWHFNGQPISASvadmSKYRILADGLLINKVTQDDTGEYTCRAYQVNSIASDMQERTV 89

Immunoglobulin domain; Members of the immunoglobulin superfamily are found in hundreds of proteins of different functions. Examples include antibodies, the giant muscle kinase titin and receptor tyrosine kinases. Immunoglobulin-like domains may be involved in protein-protein and protein-ligand interactions.

Pssm-ID: 395002 Cd Length: 86 Bit Score: 47.96 E-value: 1.45e-06

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 20127422    704 GKAVILNCSA-EGYPVPTIVWKFSKGAGVPQFQPIALNGRIqvlSNGSLLIKHVVEEDSGYYLCKVSN 770
Cdd:pfam00047   11 GDSATLTCSAsTGSPGPDVTWSKEGGTLIESLKVKHDNGRT---TQSSLLISNVTKEDAGTYTCVVNN 75

C-terminal immunoglobulin (Ig)-like domain of myomesin and M-protein; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the C-terminal immunoglobulin (Ig)-like domain of myomesin and M-protein (also known as myomesin-2). Myomesin and M-protein are both structural proteins localized to the M-band, a transverse structure in the center of the sarcomere, and are candidates for M-band bridges. Both proteins are modular, consisting mainly of repetitive Ig-like and fibronectin type III (FnIII) domains. Myomesin is expressed in all types of vertebrate striated muscle; M-protein has a muscle-type specific expression pattern. Myomesin is present in both slow and fast fibers; M-protein is present only in fast fibers. It has been suggested that myomesin acts as a molecular spring with alternative splicing as a means of modifying its elasticity.

Pssm-ID: 319300 Cd Length: 92 Bit Score: 48.36 E-value: 1.51e-06

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 20127422  237 MAGQRVELPCKALGHPEPDYRWLKDNMPLELSGRFQ------KTVTgLLIENIRPSDSGSYVCEVSNRYGTAK 303
Cdd:cd05737   14 MEGKTLNLTCNVWGDPPPEVSWLKNDQALAFLDHCNlkveagRTVY-FTINGVSSEDSGKYGLVVKNKYGSET 85

Fourth immunoglobulin (Ig)-like domain of peroxidasin; The members here are composed of the fourth immunoglobulin (Ig)-like domain in peroxidasin. Peroxidasin has a peroxidase domain and interacting extracellular motifs containing four Ig-like domains. It has been suggested that peroxidasin is secreted, and has functions related to the stabilization of the extracellular matrix. It may play a part in various other important processes such as removal and destruction of cells which have undergone programmed cell death and protection of the organism against non-self.

Pssm-ID: 143223 Cd Length: 69 Bit Score: 47.18 E-value: 1.71e-06

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 20127422  424 VSLMCNVKGTPLPTITWTLDDDPILKGGSHRISQmitsEGnvvsYLNISSSQVRDGGVYRCTANNSAG 491
Cdd:cd05746    1 VQIPCSAQGDPEPTITWNKDGVQVTESGKFHISP----EG----YLAIRDVGVADQGRYECVARNTIG 60

agrin-responsive second immunoglobulin-like domains (Ig2) of the Muscle-specific kinase (MuSK) ectodomain; a member of the I-set of Ig superfamily domains; The members here are composed of the second immunoglobulin-like (Ig) domains of the Muscle-specific kinase (MuSK) ectodomain. MuSK is a receptor tyrosine kinase specifically expressed in skeletal muscle, where it plays a central role in the formation and maintenance of the neuromuscular junction (NMJ). MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. The activation of MUSK in myotubes regulates the formation of NMJs through the regulation of different processes including the specific expression of genes in subsynaptic nuclei, the reorganization of the actin cytoskeleton and the clustering of the acetylcholine receptors (AChR) in the postsynaptic membrane. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the MuSK lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409560 [Multi-domain] Cd Length: 88 Bit Score: 47.62 E-value: 1.85e-06

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 20127422  235 KAMAGQRVELPCKALGHPEPDYRWLKDNMPLELSGRFQKTVTG-LLIENIRPSDSGSYVCEVSNRYGTA 302
Cdd:cd20968   10 TIIEGLKAVLPCTTMGNPKPSVSWIKGDDLIKENNRIAVLESGsLRIHNVQKEDAGQYRCVAKNSLGIA 78

Second immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. DSCAM is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409545 Cd Length: 95 Bit Score: 47.92 E-value: 1.88e-06

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1289 LTFSGTVTTPWMKDIVLPCKAVGDPSPAVKWMKDSNGT--PSLVTIDGRRSIFSnGSFIIRTVKAEDSGYYSCIANNNWG 1366
Cdd:cd20953    7 LSKSQPLTVSSASSIALLCPAQGYPAPSFRWYKFIEGTtrKQAVVLNDRVKQVS-GTLIIKDAVVEDSGKYLCVVNNSVG 85


                 ....
gi 20127422 1367 SDEI 1370
Cdd:cd20953   86 GESV 89

immunoglobulin-like domain of telokin and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin (Ig) domain in telokin, the C-terminal domain of myosin light chain kinase which is identical to telokin, and similar proteins. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the telokin Ig domain lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409565 [Multi-domain] Cd Length: 88 Bit Score: 47.57 E-value: 1.90e-06

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  697 RDQDGIYGKAVILNCSAEGYPVPTIVWkfskgagVPQFQPIALNGRIQVLSNG----SLLIKHVVEEDSGYYLCKVSNDV 772
Cdd:cd20973    5 RDKEVVEGSAARFDCKVEGYPDPEVKW-------MKDDNPIVESRRFQIDQDEdglcSLIISDVCGDDSGKYTCKAVNSL 77


                 .
gi 20127422  773 G 773
Cdd:cd20973   78 G 78

Immunoglobulin domain I1 of the titin I-band and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin domain I1 of the titin I-band and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. The two sheets are linked together by a conserved disulfide bond between B strand and F strand. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The Ig I1 domain of the titin I-band is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409543 [Multi-domain] Cd Length: 94 Bit Score: 47.80 E-value: 2.19e-06

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1301 KDIVLPCKAVGDPSPAVKWMKdsNGTP-SLVTIDGRRSIFSNG---SFIIRTVKAEDSGYYSCIANNNWG 1366
Cdd:cd20951   16 SDAKLRVEVQGKPDPEVKWYK--NGVPiDPSSIPGKYKIESEYgvhVLHIRRVTVEDSAVYSAVAKNIHG 83

Fibronectin type 3 domain [General function prediction only];

Pssm-ID: 442628 [Multi-domain] Cd Length: 603 Bit Score: 52.70 E-value: 2.22e-06

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1143 ITTTQPSLELDGLEKYTNYSIQVLAFTRAGDGVRSEQIFTRTKEDVPGPPAGVKAAAASASMVFVSWLPPLKLNgiIRKY 1222
Cdd:COG3401  187 VTSTTLVDGGGDIEPGTTYYYRVAATDTGGESAPSNEVSVTTPTTPPSAPTGLTATADTPGSVTLSWDPVTESD--ATGY 264

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1223 TVF----CSHPYPTVisefeASPDSFSYRIPNLSRNRQYSVWVVAVTSAG-RGNSSEIITVEPLAKAPARILTFSGTVTT 1297
Cdd:COG3401  265 RVYrsnsGDGPFTKV-----ATVTTTSYTDTGLTNGTTYYYRVTAVDAAGnESAPSNVVSVTTDLTPPAAPSGLTATAVG 339

                        170       180       190       200       210       220       230       240
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1298 PwmKDIVLPCKAVGDPSPA---VKWMKDSNGTPSLVTidgrrSIFSNGSFIIRTVKAEDSGYYSCIANNNWG-----SDE 1369
Cdd:COG3401  340 S--SSITLSWTASSDADVTgynVYRSTSGGGTYTKIA-----ETVTTTSYTDTGLTPGTTYYYKVTAVDAAGnesapSEE 412

                        250       260       270       280       290
                 ....*....|....*....|....*....|....*....|....*....|....*
gi 20127422 1370 I---ILNLQVQVPPDQPRLTVSKTTSSSITLSWLPGDNGGSSIRGYILQYSEDNS 1421
Cdd:COG3401  413 VsatTASAASGESLTASVDAVPLTDVAGATAAASAASNPGVSAAVLADGGDTGNA 467

Immunoglobulin-like Ig0 domain of basigin-1 (BSG1) and similar proteins; The members here are composed of the immunoglobulin (Ig) domain of the collagenase stimulatory factor, basigin-1 (BSG1; also known as Cluster of Differentiation 147 (CD147) and Extracellular Matrix Metalloproteinase Inducer (EMMPRIN)) and similar proteins. CD147 is a transmembrane glycoprotein that belongs to the immunoglobulin superfamily. It is expressed in nearly all cells including platelets and fibroblasts and is involved in inflammatory diseases, and cancer progression. CD147 is highly expressed in several cancers and used as a prognostic marker. The two primary isoforms of CD147 that are related to cancer progression have been identified: CD147 Ig1-Ig2 (also called Basigin-2) that is ubiquitously expressed in most tissues and CD147 Ig0-Ig1-Ig2 (also called Basigin-1) that is retinal specific and implicated in retinoblastoma. Studies showed that CD147 Ig0 domain is a potent stimulator of interleukin-6 and suggest that the CD147 Ig0 dimer is the functional unit required for activity.

Pssm-ID: 409534 Cd Length: 116 Bit Score: 48.42 E-value: 2.27e-06

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  692 FVVQPRDQDGIYGKAVILNCSAEGYPVPTIVWKFSKGAG---VPQFQPIALNGRIQV------LSNGSLLIKHVVEEDSG 762
Cdd:cd20940    3 FIKSPLSQQRLVGDSVELHCEAVGSPIPEIQWWFEGQEPneiCSQLWDGARLDRVHInatyhqHATSTISIDNLTEEDTG 82


                 ....*....
gi 20127422  763 YYLCKVSND 771
Cdd:cd20940   83 TYECRASND 91

Immunoglobulin (Ig)-like I-set domain of Neural Cell Adhesion Molecule 1 (NCAM-1); The members here are composed of the fourth Ig domain of Neural Cell Adhesion Molecule 1(NCAM-1). NCAM plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM) and heterophilic (NCAM-non-NCAM) interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves Ig1, Ig2, and Ig3. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions), through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain. One of the unique features of I-set domains is the lack of a C" strand. The structures of this group show that the Ig domain lacks this strand and thus is a member of the I-set of Ig domains.

Pssm-ID: 143277 [Multi-domain] Cd Length: 97 Bit Score: 47.67 E-value: 2.30e-06

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  407 PKIISAFSEKVVSPAEPVSLMCNVKGTPLPTITWTLDDDPILKGGSHRISQMITSEGNVVSYLNISSSQVRDGGVYRCTA 486
Cdd:cd05869    3 PKITYVENQTAMELEEQITLTCEASGDPIPSITWRTSTRNISSEEKTLDGHIVVRSHARVSSLTLKYIQYTDAGEYLCTA 82


                 ....*.
gi 20127422  487 NNSAGV 492
Cdd:cd05869   83 SNTIGQ 88

Fourth immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM); The members here are composed of the fourth immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region, and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, and spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM.

Pssm-ID: 409453 [Multi-domain] Cd Length: 89 Bit Score: 47.58 E-value: 2.37e-06

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 20127422  239 GQRVELPCKALGHPEPDYRWLKDNMPLELSGRFQK---TVTGLLIENIRPSDSGSYVCEVSNRYGTAKVIGRLYV 310
Cdd:cd05867   14 GETARLDCQVEGIPTPNITWSINGAPIEGTDPDPRrhvSSGALILTDVQPSDTAVYQCEARNRHGNLLANAHVHV 88

Fourth immunoglobulin (Ig)-like domain of hemolin, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain of hemolin and similar proteins. Hemolin, an insect immunoglobulin superfamily (IgSF) member containing four Ig-like domains, is a lipopolysaccharide-binding immune protein induced during bacterial infection. Hemolin shares significant sequence similarity with the first four Ig-like domains of the transmembrane cell adhesion molecules (CAMs) of the L1 family. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The fourth Ig-like domain of hemolin is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409570 [Multi-domain] Cd Length: 88 Bit Score: 47.39 E-value: 2.38e-06

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  787 PAMITSYPNTTLATQGQKKEMSCTAHGEKPIIVRWEKEDRIINPEMARYLVSTkevgeeviSTLQILPTVREDSGFFSCH 866
Cdd:cd20978    1 PKFIQKPEKNVVVKGGQDVTLPCQVTGVPQPKITWLHNGKPLQGPMERATVED--------GTLTIINVQPEDTGYYGCV 72

                         90
                 ....*....|....*.
gi 20127422  867 AINSYGEDRGIIQLTV 882
Cdd:cd20978   73 ATNEIGDIYTETLLHV 88

Second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of the Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit-2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409389 [Multi-domain] Cd Length: 87 Bit Score: 47.01 E-value: 2.88e-06

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  414 SEKVVSPAEPVSLMCNV-KGTPLPTITWTLDDDPILKGGSHRisqMITSEGNVVsylnISSSQVRDGGVYRCTANNSAGV 492
Cdd:cd05724    5 SDTQVAVGEMAVLECSPpRGHPEPTVSWRKDGQPLNLDNERV---RIVDDGNLL----IAEARKSDEGTYKCVATNMVGE 77

Fifth Ig-like domain of Roundabout (Robo) homolog 1/2, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fifth Ig-like domain of Roundabout (Robo) homolog 1/2 and similar domains. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, -2, and -3), and three mammalian Slit homologs (Slit-1,-2, -3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, -2, and -3 are expressed by commissural neurons in the vertebrate spinal cord and Slits 1, -2, -3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of slit responsiveness, antagonizes slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be is the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. The fifth Ig-like domain of Robo 1 and 2 is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors

Pssm-ID: 409544 [Multi-domain] Cd Length: 87 Bit Score: 47.11 E-value: 3.03e-06

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  499 INVRGPAsirpmkNITAIAGRDTYIHCRVIGYPYYSIKWYKNSNLLPFNHRQVAFENNGTLKLSDVQKEvDEGEYTCnvl 578
Cdd:cd20952    1 IILQGPQ------NQTVAVGGTVVLNCQATGEPVPTISWLKDGVPLLGKDERITTLENGSLQIKGAEKS-DTGEYTC--- 70

                         90
                 ....*....|....*..
gi 20127422  579 VQPQLSTSQSVHVTVKV 595
Cdd:cd20952   71 VALNLSGEATWSAVLDV 87

Third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM); The members here are composed of the third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains, five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM.

Pssm-ID: 409460 [Multi-domain] Cd Length: 83 Bit Score: 46.83 E-value: 3.50e-06

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 20127422  236 AMAGQRVELPCKALGHPEPDYRWLKDNMPLELS----GRFQKTvtgLLIENIRPSDSGSYVCEVSNRYGTAK 303
Cdd:cd05876    7 ALRGQSLVLECIAEGLPTPTVKWLRPSGPLPPDrvkyQNHNKT---LQLLNVGESDDGEYVCLAENSLGSAR 75

Immunoglobulin domain; This domain contains immunoglobulin-like domains.

Pssm-ID: 464026 [Multi-domain] Cd Length: 79 Bit Score: 46.62 E-value: 3.50e-06

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422    704 GKAVILNCSAEGYPVPTIVWkfSKGAGVpqfqpialngriqVLSNGSLLIKHVVEEDSGYYLCKVSNDVGADVSKSMYLT 783
Cdd:pfam13895   14 GEPVTLTCSAPGNPPPSYTW--YKDGSA-------------ISSSPNFFTLSVSAEDSGTYTCVARNGRGGKVSNPVELT 78


                   .
gi 20127422    784 V 784
Cdd:pfam13895   79 V 79

Second immunoglobulin (Ig)-like domain of a Follistatin-related protein 5, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain found in human Follistatin-related protein 5 (FSTL5) and a follistatin-like molecule encoded by the CNS-related Mahya gene. Mahya genes have been retained in certain Bilaterian branches during evolution. They are conserved in Hymenoptera and Deuterostomes, but are absent from other metazoan species such as fruit fly and nematode. Mahya proteins are secretory, with a follistatin-like domain (Kazal-type serine/threonine protease inhibitor domain and EF-hand calcium-binding domain), two Ig-like domains, and a novel C-terminal domain. Mahya may be involved in learning and memory and in processing of sensory information in Hymenoptera and vertebrates. Follistatin is a secreted, multidomain protein that binds activins with high affinity and antagonizes their signaling.

Pssm-ID: 409399 [Multi-domain] Cd Length: 93 Bit Score: 47.26 E-value: 3.55e-06

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 20127422  239 GQRVELPCKALGHPEPDYRWLKDNMPL--ELSGRFQKTVTG--LLIENIRPSDSGSYVCEVSNRYGTAKVIGRLYVKQ 312
Cdd:cd05736   15 GVEASLRCHAEGIPLPRVQWLKNGMDInpKLSKQLTLIANGseLHISNVRYEDTGAYTCIAKNEGGVDEDISSLFVED 92

Third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM); The members here are composed of the third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains, five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM.

Pssm-ID: 409460 [Multi-domain] Cd Length: 83 Bit Score: 46.83 E-value: 3.71e-06

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  704 GKAVILNCSAEGYPVPTIVWKFSKGAGVPQfqpialngRIQVLS-NGSLLIKHVVEEDSGYYLCKVSNDVGAdVSKSMYL 782
Cdd:cd05876   10 GQSLVLECIAEGLPTPTVKWLRPSGPLPPD--------RVKYQNhNKTLQLLNVGESDDGEYVCLAENSLGS-ARHAYYV 80


                 ...
gi 20127422  783 TVK 785
Cdd:cd05876   81 TVE 83

Immunoglobulin (Ig)-like domain of titin and similar proteins; The members here are composed of the immunoglobulin (Ig)-like domain found in titin-like proteins and similar proteins. Titin (also called connectin) is a fibrous sarcomeric protein specifically found in vertebrate striated muscle. Titin is a giant protein; depending on isoform composition, it ranges from 2970 to 3700 kDa, and is of a length that spans half a sarcomere. Titin largely consists of multiple repeats of Ig-like and fibronectin type 3 (FN-III)-like domains. Titin connects the ends of myosin thick filaments to Z disks and extends along the thick filament to the H zone. It appears to function similarly to an elastic band, keeping the myosin filaments centered in the sarcomere during muscle contraction or stretching. Within the sarcomere, titin is also attached to or is associated with myosin binding protein C (MyBP-C). MyBP-C appears to contribute to the generation of passive tension by titin and like titin has repeated Ig-like and FN-III domains. Also included in this group are worm twitchin and insect projectin, thick filament proteins of invertebrate muscle which also have repeated Ig-like and FN-III domains.

Pssm-ID: 409406 [Multi-domain] Cd Length: 82 Bit Score: 46.43 E-value: 3.96e-06

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 20127422  241 RVELPCKalGHPEPDYRWLKDNMPLELSGRFQKTVTG----LLIENIRPSDSGSYVCEVSNRYGTAKVI 305
Cdd:cd05748   11 RLDIPIK--GRPTPTVTWSKDGQPLKETGRVQIETTAsstsLVIKNAKRSDSGKYTLTLKNSAGEKSAT 77

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor, and similar domains; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor. FGF receptors bind FGF signaling polypeptides. FGFs participate in multiple processes such as morphogenesis, development, and angiogenesis. FGFs bind to four FGF receptor tyrosine kinases (FGFR1, FGFR2, FGFR3, FGFR4). Receptor diversity is controlled by alternative splicing producing splice variants with different ligand binding characteristics and different expression patterns. FGFRs have an extracellular region comprised of three Ig-like domains, a single transmembrane helix, and an intracellular tyrosine kinase domain. Ligand binding and specificity reside in the Ig-like domains 2 and 3, and the linker region that connects these two. FGFR activation and signaling depend on FGF-induced dimerization, a process involving cell surface heparin or heparin sulfate proteoglycans. This group also contains fibroblast growth factor (FGF) receptor like-1(FGFRL1). FGFRL1 does not have a protein tyrosine kinase domain at its C-terminus; neither does its cytoplasmic domain appear to interact with a signaling partner. It has been suggested that FGFRL1 may not have any direct signaling function, but instead acts as a decoy receptor trapping FGFs and preventing them from binding other receptors.

Pssm-ID: 409393 [Multi-domain] Cd Length: 95 Bit Score: 47.21 E-value: 4.08e-06

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 20127422  704 GKAVILNCSAEGYPVPTIVW-KFSKgagvpQFQPIALNGRIQVLSNG-SLLIKHVVEEDSGYYLCKVSNDVG 773
Cdd:cd05729   19 ANKVRLECGAGGNPMPNITWlKDGK-----EFKKEHRIGGTKVEEKGwSLIIERAIPRDKGKYTCIVENEYG 85

Immunoglobulin (Ig)-like domain of myotilin, palladin, and myopalladin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the immunoglobulin (Ig)-like domain in myotilin, palladin, and myopalladin. Myotilin, palladin, and myopalladin function as scaffolds that regulate actin organization. Myotilin and myopalladin are most abundant in skeletal and cardiac muscle; palladin is ubiquitously expressed in the organs of developing vertebrates and plays a key role in cellular morphogenesis. The three family members each interact with specific molecular partners with all three binding to alpha-actinin; In addition, palladin also binds to vasodilator-stimulated phosphoprotein (VASP) and ezrin, myotilin binds to filamin and actin, and myopalladin also binds to nebulin and cardiac ankyrin repeat protein (CARP). This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409405 [Multi-domain] Cd Length: 91 Bit Score: 46.72 E-value: 4.42e-06

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 20127422  504 PASIRPMKNITAIAGRDTYIHCRVIGYPYYSIKWYKNSNLLPFNHRQVAFENNG---TLKLSDVQKEvDEGEYTC 575
Cdd:cd05744    1 PHFLQAPGDLEVQEGRLCRFDCKVSGLPTPDLFWQLNGKPVRPDSAHKMLVRENgrhSLIIEPVTKR-DAGIYTC 74

Immunoglobulin (Ig)-like ectodomain of the LRIG1 (Leucine-rich Repeats And Immunoglobulin-like Domains Protein 1) and similar proteins; member of the I-set of IgSF domains; The members here are composed of subgroup of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. The ectodomain of LRIG1 has two distinct regions: the proposed 15 LRRs and three Ig-like domains closer to the membrane. LRIG1 has been reported to interact with many receptor tyrosine kinases, GDNF/c-Ret, E-cadherin, JAK/STAT, c-Met, and the EGFR family signaling systems. Immunoglobulin Superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The structure of the LRIG1 extracellular Ig domain lacks a C" strand and thus is better described as a member of the I-set of IgSF domains.

Pssm-ID: 409420 [Multi-domain] Cd Length: 91 Bit Score: 46.84 E-value: 4.61e-06

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 20127422  238 AGQRVELPCKALGHPEPDYRWLKD---NMPLELSGRFQKTVTG--LLIENIRPSDSGSYVCEVSNRYGT 301
Cdd:cd05763   13 AGSTARLECAATGHPTPQIAWQKDggtDFPAARERRMHVMPEDdvFFIVDVKIEDTGVYSCTAQNSAGS 81

First immunoglobulin (Ig)-like domain in neogenin, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain in neogenin and related proteins. Neogenin is a cell surface protein which is expressed in the developing nervous system of vertebrate embryos in the growing nerve cells. It is also expressed in other embryonic tissues and may play a general role in developmental processes such as cell migration, cell-cell recognition, and tissue growth regulation. Included in this group is the tumor suppressor protein DCC which is deleted in colorectal carcinoma. DCC and neogenin each have four Ig-like domains followed by six fibronectin type III domains, a transmembrane domain, and an intracellular domain. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409387 Cd Length: 97 Bit Score: 46.70 E-value: 5.11e-06

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  791 TSYPNTTLATQGQKKEMSCTAHGEKPIIVRWEKEDRIINPEMA--RYLVSTkevGEEVISTLQILPTVREDSGFFSCHAI 868
Cdd:cd05722    5 LSEPSDIVAMRGGPVVLNCSAESDPPPKIEWKKDGVLLNLVSDerRQQLPN---GSLLITSVVHSKHNKPDEGFYQCVAQ 81


                 ....*
gi 20127422  869 N-SYG 872
Cdd:cd05722   82 NeSLG 86

Fibronectin type 3 domain [General function prediction only];

Pssm-ID: 442628 [Multi-domain] Cd Length: 603 Bit Score: 51.54 E-value: 5.16e-06

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1232 TVISEFEASPDSFSYRIPNLSRNRQYSVWVVAVTSAGRGNSSEIITVEPLAKAPARILTFSGTVTTPwmkdivlpckavg 1311
Cdd:COG3401  180 VATTSLTVTSTTLVDGGGDIEPGTTYYYRVAATDTGGESAPSNEVSVTTPTTPPSAPTGLTATADTP------------- 246

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1312 dPSPAVKWmkDSNGTPSLVTIDGRRSIFSNGSF-IIRTVKA---EDSG-------YYSCIANNNWG-----SDEIILNLQ 1375
Cdd:COG3401  247 -GSVTLSW--DPVTESDATGYRVYRSNSGDGPFtKVATVTTtsyTDTGltngttyYYRVTAVDAAGnesapSNVVSVTTD 323

                        170       180       190       200       210       220       230       240
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1376 VQvPPDQPR-LTVSKTTSSSITLSWlpGDNGGSSIRGYILQYSEDNSEQWGSFPISPSERSYRLENLKCGTWYKFTLTAQ 1454
Cdd:COG3401  324 LT-PPAAPSgLTATAVGSSSITLSW--TASSDADVTGYNVYRSTSGGGTYTKIAETVTTTSYTDTGLTPGTTYYYKVTAV 400

                        250
                 ....*....|....*...
gi 20127422 1455 NGVGP-GRISEIIEAKTL 1471
Cdd:COG3401  401 DAAGNeSAPSEEVSATTA 418

Second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of the Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit-2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409389 [Multi-domain] Cd Length: 87 Bit Score: 46.24 E-value: 5.39e-06

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 20127422  318 ISPRKVKSSVGSQVSLSCSV-TGTEDQELSWYRNGEILNPgKNVRITGINHENLIMDHMVKSDGGAYQC 385
Cdd:cd05724    2 VEPSDTQVAVGEMAVLECSPpRGHPEPTVSWRKDGQPLNL-DNERVRIVDDGNLLIAEARKSDEGTYKC 69

Immunoglobulin domain; The members here are composed of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. Members of this group are components of immunoglobulin, neuroglia, cell surface glycoproteins, including T-cell receptors, CD2, CD4, CD8, and membrane glycoproteins, including butyrophilin and chondroitin sulfate proteoglycan core protein. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. Ig superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Typically, the V-set domains have A, B, E, and D strands in one sheet and A', G, F, C, C' and C" in the other. The structures in C1-set are smaller than those in the V-set; they have one beta sheet that is formed by strands A, B, E, and D and the other by strands G, F, C, and C'. Moreover, a C1-set Ig domain contains a short C' strand (three residues) and lacks A' and C" strand. Unlike other Ig domain sets, C2-set structures do not have a D strand. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409353 [Multi-domain] Cd Length: 70 Bit Score: 45.78 E-value: 5.78e-06

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 20127422   44 VPCPAAGIPPVTLRWYLATGE-EIYDVPGIRHVHPNGTLQIFPFPPSsfstliHDNTYYCTAENPSGKIRSQDV 116
Cdd:cd00096    3 LTCSASGNPPPTITWYKNGKPlPPSSRDSRRSELGNGTLTISNVTLE------DSGTYTCVASNSAGGSASASV 70

Fifth immunoglobulin (Ig)-like domain of Kirrel (kin of irregular chiasm-like) 3 protein; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the fifth immunoglobulin (Ig)-like domain of Kirrel (kin of irregular chiasm-like) 3 protein (also known as Neph2). This protein has five Ig-like domains, one transmembrane domain, and a cytoplasmic tail. Included in this group is mammalian Kirrel (Neph1). These proteins contain multiple Ig domains, have properties of cell adhesion molecules, and are important in organ development. Neph1 and 2 may mediate axonal guidance and synapse formation in certain areas of the CNS. In the kidney they participate in the formation of the slit diaphragm.

Pssm-ID: 409479 Cd Length: 98 Bit Score: 46.48 E-value: 5.96e-06

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  787 PAMITSYPnTTLATQGQKKEMSCTAHGEKP---IIVRWeKEDRIINPEMARYLVSTKEVGEEVISTLQILPTVRED-SGF 862
Cdd:cd05898    2 PPIISSEQ-VQYAVRGERGKVKCFIGSTPPpdrIAWAW-KENVLESGTLERYTVERTSTGSGVLSTLTINNIMEADfQTH 79

                         90
                 ....*....|....*...
gi 20127422  863 FSCHAINSYGEDRGIIQL 880
Cdd:cd05898   80 YNCTAWNSFGSGTAIIQL 97

Second immunoglobulin (Ig)-like domain of the receptor protein tyrosine phosphatase (RPTP)-F; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain found in the receptor protein tyrosine phosphatase (RPTP)-F, also known as LAR. LAR belongs to the RPTP type IIa subfamily. Members of this subfamily are cell adhesion molecule-like proteins involved in central nervous system (CNS) development. They have large extracellular portions comprised of multiple Ig-like domains and two to nine fibronectin type III (FNIII) domains and a cytoplasmic portion having two tandem phosphatase domains.

Pssm-ID: 409400 [Multi-domain] Cd Length: 91 Bit Score: 46.54 E-value: 6.00e-06

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  685 IVRVPPKFVVQPRDQdgiygKAVILnCSAEGYPVPTIVWkfskgagVPQFQPIAL---NGRIQVLSNGSLLIKHVVEEDS 761
Cdd:cd05738    1 IIDMGPQLKVVEKAR-----TATML-CAASGNPDPEISW-------FKDFLPVDTatsNGRIKQLRSGALQIENSEESDQ 67

                         90       100
                 ....*....|....*....|....
gi 20127422  762 GYYLCKVSNDVGADVSKSMYLTVK 785
Cdd:cd05738   68 GKYECVATNSAGTRYSAPANLYVR 91

Third immunoglobulin (Ig) domain of contactin-1; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-1. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-1 is differentially expressed in tumor tissues and may through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 143259 Cd Length: 88 Bit Score: 46.17 E-value: 6.51e-06

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  689 PPKFVVQPRDQDGIYGKAVILNCSAEGYPVPTIVWKFSKGAgVPQFQPIALNGRIqvlsngsLLIKHVVEEDSGYYLCKV 768
Cdd:cd05851    1 PADINVKFKDTYALKGQNVTLECFALGNPVPVIRWRKILEP-MPATAEISMSGAV-------LKIFNIQPEDEGTYECEA 72


                 ....*..
gi 20127422  769 SNDVGAD 775
Cdd:cd05851   73 ENIKGKD 79

Immunoglobulin (Ig)-like domain of myotilin, palladin, and myopalladin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the immunoglobulin (Ig)-like domain in myotilin, palladin, and myopalladin. Myotilin, palladin, and myopalladin function as scaffolds that regulate actin organization. Myotilin and myopalladin are most abundant in skeletal and cardiac muscle; palladin is ubiquitously expressed in the organs of developing vertebrates and plays a key role in cellular morphogenesis. The three family members each interact with specific molecular partners with all three binding to alpha-actinin; In addition, palladin also binds to vasodilator-stimulated phosphoprotein (VASP) and ezrin, myotilin binds to filamin and actin, and myopalladin also binds to nebulin and cardiac ankyrin repeat protein (CARP). This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409405 [Multi-domain] Cd Length: 91 Bit Score: 46.33 E-value: 6.79e-06

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 20127422 1305 LPCKAVGDPSPAVKWMKDSNgtpsLVTIDGRRSIFSNG----SFIIRTVKAEDSGYYSCIANNNWGSDEIILNLQV 1376
Cdd:cd05744   20 FDCKVSGLPTPDLFWQLNGK----PVRPDSAHKMLVREngrhSLIIEPVTKRDAGIYTCIARNRAGENSFNAELVV 91

Fourth immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; Members here are composed the fourth immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, Robo3), and three mammalian Slit homologs (Slit-1, Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, and Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409391 [Multi-domain] Cd Length: 98 Bit Score: 46.49 E-value: 7.08e-06

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 20127422  239 GQRVELPCKALGHPEPDYRWLKD--------NMPLELSGRFQKTVTG-LLIENIRPSDSGSYVCEVSNRYGT 301
Cdd:cd05726   14 GRTVTFQCETKGNPQPAIFWQKEgsqnllfpYQPPQPSSRFSVSPTGdLTITNVQRSDVGYYICQALNVAGS 85

Fourth Ig domain of the neural cell adhesion molecule contactin-2, and similar domains; The members here are composed of the fourth Ig domain of the neural cell adhesion molecule contactin-2. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-2 (also called TAG-1, axonin-1) facilitates cell adhesion by homophilic binding between molecules in apposed membranes. The first four Ig domains form the intermolecular binding fragment which arranges as a compact U-shaped module by contacts between Ig domains 1 and 4, and domains 2 and 3. It has been proposed that a linear zipper-like array forms, from contactin-2 molecules alternatively provided by the two apposed membranes.

Pssm-ID: 143205 [Multi-domain] Cd Length: 85 Bit Score: 46.05 E-value: 7.12e-06

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  696 PRDQDGIYGKAVILNCSAEGYPVPTIVWkFSKGagvpqfQPIALNGRIQVlSNGSLLIKHVVEEDSGYYLCKVSNDVGAd 775
Cdd:cd05728    6 ISDTEADIGSSLRWECKASGNPRPAYRW-LKNG------QPLASENRIEV-EAGDLRITKLSLSDSGMYQCVAENKHGT- 76


                 ....*....
gi 20127422  776 VSKSMYLTV 784
Cdd:cd05728   77 IYASAELAV 85

Eighth immunoglobulin (Ig)-like domain of human myosin light-chain kinase (MLCK) and similar protein; member of the I-set of IgSF domains; The members here are composed of the eighth immunoglobulin (Ig)-like domain of human myosin light-chain kinase (MLCK) and similar proteins. Myosin light-chain kinase (MLCK) is a key regulator of different forms of cell motility involving actin and myosin II. Agonist stimulation of smooth muscle cells increases cytosolic Ca2+ which binds calmodulin. This Ca2+-calmodulin complex in turn binds to and activates MLCK. Activated MLCK leads to the phosphorylation of the 20 kDa myosin regulatory light chain (RLC) of myosin II and the stimulation of actin-activated myosin MgATPase activity. MLCK is widely present in vertebrate tissues; it phosphorylates the 20 kDa RLC of both smooth and nonmuscle myosin II. Phosphorylation leads to the activation of the myosin motor domain and altered structural properties of myosin II. In smooth muscle MLCK it is involved in initiating contraction. In nonmuscle cells, MLCK may participate in cell division and cell motility; it has been suggested MLCK plays a role in cardiomyocyte differentiation and contraction through regulation of nonmuscle myosin II.

Pssm-ID: 409419 Cd Length: 99 Bit Score: 46.49 E-value: 7.27e-06

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  787 PAMITSYPNTTLATQGQKKEMSCTAHGEKPIIVRWEKEDRIINPEMARYLVSTkevgeEVISTLQILPTVREDSGFFSCH 866
Cdd:cd05762    1 PPQIIQFPEDMKVRAGESVELFCKVTGTQPITCTWMKFRKQIQEGEGIKIENT-----ENSSKLTITEGQQEHCGCYTLE 75

                         90       100
                 ....*....|....*....|...
gi 20127422  867 AINSYGEDRGIIQLTVQEPPDPP 889
Cdd:cd05762   76 VENKLGSRQAQVNLTVVDKPDPP 98

Immunoglobulin domain; Members of the immunoglobulin superfamily are found in hundreds of proteins of different functions. Examples include antibodies, the giant muscle kinase titin and receptor tyrosine kinases. Immunoglobulin-like domains may be involved in protein-protein and protein-ligand interactions.

Pssm-ID: 395002 Cd Length: 86 Bit Score: 46.03 E-value: 7.71e-06

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 20127422    238 AGQRVELPCKA-LGHPEPDYRWLKDNMPLELS-----GRFQKTVTGLLIENIRPSDSGSYVCEVSNR 298
Cdd:pfam00047   10 EGDSATLTCSAsTGSPGPDVTWSKEGGTLIESlkvkhDNGRTTQSSLLISNVTKEDAGTYTCVVNNP 76

Immunoglobulin (Ig)-like domain in neuregulins; The members here are composed of the immunoglobulin (Ig)-like domain in neuregulins (NRGs). NRGs are signaling molecules which participate in cell-cell interactions in the nervous system, breast, heart, and other organ systems, and are implicated in the pathology of diseases including schizophrenia, multiple sclerosis, and breast cancer. There are four members of the neuregulin gene family (NRG-1, NRG-2, NRG-3, and NRG-4). The NRG-1 protein, binds to and activates the tyrosine kinases receptors ErbB3 and ErbB4, initiating signaling cascades. The other NRGs proteins bind one or the other or both of these ErbBs. NRG-1 has multiple functions: in the brain it regulates various processes such as radial glia formation and neuronal migration, dendritic development, and expression of neurotransmitters receptors, while in the peripheral nervous system NRG-1 regulates processes such as target cell differentiation, and Schwann cell survival. There are many NRG-1 isoforms which arise from the alternative splicing of mRNA. Less is known of the functions of the other NRGs. NRG-2 and NRG-3 are expressed predominantly in the nervous system. NRG-2 is expressed by motor neurons and terminal Schwann cells, and is concentrated near synaptic sites and may be a signal that regulates synaptic differentiation. NRG-4 has been shown to direct pancreatic islet cell development towards the delta-cell lineage.

Pssm-ID: 409408 [Multi-domain] Cd Length: 92 Bit Score: 45.97 E-value: 7.75e-06

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1301 KDIVLPCKAVGD-PSPAVKWMKDSN----GTPSLVTIDGRRSifsNGSFIIRTVKAEDSGYYSCIANNNWGSDEIILNLQ 1375
Cdd:cd05750   15 SKLVLKCEATSEnPSPRYRWFKDGKelnrKRPKNIKIRNKKK---NSELQINKAKLEDSGEYTCVVENILGKDTVTGNVT 91


                 .
gi 20127422 1376 V 1376
Cdd:cd05750   92 V 92

Immunoglobulin (Ig)-like domain of vascular endothelial growth factor receptor (VEGFR); member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the immunoglobulin (Ig)-like domain of vascular endothelial growth factor receptor (VEGFR). The VEGFRs have an extracellular component with seven Ig-like domains, a transmembrane segment, and an intracellular tyrosine kinase domain interrupted by a kinase-insert domain. The VEGFR family consists of three members, VEGFR-1 (Flt-1), VEGFR-2 (KDR/Flk-1), and VEGFR-3 (Flt-4). VEGFRs bind VEGFs with high affinity at the Ig-like domains. VEGF-A is important to the growth and maintenance of vascular endothelial cells and to the development of new blood- and lymphatic-vessels in physiological and pathological states. VEGFR-2 is a major mediator of the mitogenic, angiogenic, and microvascular permeability-enhancing effects of VEGF-A. VEGFR-1 may play an inhibitory part in these processes by binding VEGF and interfering with its interaction with VEGFR-2. VEGFR-1 has a signaling role in mediating monocyte chemotaxis. VEGFR-1 and VEGFR-2 may mediate a chemotactic and a survival signal in hematopoietic stem cells or leukemia cells. VEGFR-3 has been shown to be involved in tumor angiogenesis and growth. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409365 Cd Length: 90 Bit Score: 46.05 E-value: 7.95e-06

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 20127422  231 FDHRK-----AMAGQR-VELPCKALGHPEPDYRWLKDNMPLELSGRFqKTVTGLLIENIRPSDSGSYVCEVSN 297
Cdd:cd04976    4 VKHRKqqvleATAGKRsVRLPMKVKAYPPPEVVWYKDGLPLTEKARY-LTRHSLIIKEVTEEDTGNYTILLSN 75

Third immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, and Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409390 [Multi-domain] Cd Length: 83 Bit Score: 45.85 E-value: 8.11e-06

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 20127422  507 IRPMKNITAIAGRDTYIHCRVIGYPYYSIKWYKNSNLLPFNHRQVAFENngTLKLSDVQKEvDEGEYTC 575
Cdd:cd05725    1 VKRPQNQVVLVDDSAEFQCEVGGDPVPTVRWRKEDGELPKGRYEILDDH--SLKIRKVTAG-DMGSYTC 66

Fourth immunoglobulin (Ig)-like domain of L1, Ng-CAM (Neuron-glia CAM cell adhesion molecule), and NrCAM (Ng-CAM-related); The members here are composed of the fourth immunoglobulin (Ig)-like domain of L1, Ng-CAM (Neuron-glia CAM cell adhesion molecule), and NrCAM (Ng-CAM-related). These proteins belong to the L1 subfamily of cell adhesion molecules (CAMs) and are comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. These molecules are primarily expressed in the nervous system. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth.

Pssm-ID: 409367 [Multi-domain] Cd Length: 89 Bit Score: 45.90 E-value: 8.52e-06

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 20127422  239 GQRVELPCKALGHPEPDYRWLKDNMPLE-LSGRFQKTVTG--LLIENIRPSDSGSYVCEVSNRYGTA 302
Cdd:cd04978   14 GETGELICEAEGNPQPTITWRLNGVPIEpAPEDMRRTVDGrtLIFSNLQPNDTAVYQCNASNVHGYL 80

Third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM), and similar domains; The members here are composed of the third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, and spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM and human neurofascin.

Pssm-ID: 409394 [Multi-domain] Cd Length: 83 Bit Score: 45.48 E-value: 9.03e-06

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 20127422  704 GKAVILNCSAEGYPVPTIVWkFSKGAGVPqfqpialNGRIQVLS-NGSLLIKHVVEEDSGYYLCKVSNDVG 773
Cdd:cd05731   10 GGVLLLECIAEGLPTPDIRW-IKLGGELP-------KGRTKFENfNKTLKIENVSEADSGEYQCTASNTMG 72

Fourth immunoglobulin (Ig)-like domain of hemolin, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain of hemolin and similar proteins. Hemolin, an insect immunoglobulin superfamily (IgSF) member containing four Ig-like domains, is a lipopolysaccharide-binding immune protein induced during bacterial infection. Hemolin shares significant sequence similarity with the first four Ig-like domains of the transmembrane cell adhesion molecules (CAMs) of the L1 family. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The fourth Ig-like domain of hemolin is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409570 [Multi-domain] Cd Length: 88 Bit Score: 45.85 E-value: 9.80e-06

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422   25 YFVNASLQEVVFASTTGTLVPCPAAGIPPVTLRWyLATGEEIYDVPGIRHVHpNGTLQIFPFPPSsfstlihDNTYY-CT 103
Cdd:cd20978    2 KFIQKPEKNVVVKGGQDVTLPCQVTGVPQPKITW-LHNGKPLQGPMERATVE-DGTLTIINVQPE-------DTGYYgCV 72

                         90
                 ....*....|.
gi 20127422  104 AENPSGKIRSQ 114
Cdd:cd20978   73 ATNEIGDIYTE 83

Immunoglobulin (Ig)-like domain of titin and similar proteins; The members here are composed of the immunoglobulin (Ig)-like domain found in titin-like proteins and similar proteins. Titin (also called connectin) is a fibrous sarcomeric protein specifically found in vertebrate striated muscle. Titin is a giant protein; depending on isoform composition, it ranges from 2970 to 3700 kDa, and is of a length that spans half a sarcomere. Titin largely consists of multiple repeats of Ig-like and fibronectin type 3 (FN-III)-like domains. Titin connects the ends of myosin thick filaments to Z disks and extends along the thick filament to the H zone. It appears to function similarly to an elastic band, keeping the myosin filaments centered in the sarcomere during muscle contraction or stretching. Within the sarcomere, titin is also attached to or is associated with myosin binding protein C (MyBP-C). MyBP-C appears to contribute to the generation of passive tension by titin and like titin has repeated Ig-like and FN-III domains. Also included in this group are worm twitchin and insect projectin, thick filament proteins of invertebrate muscle which also have repeated Ig-like and FN-III domains.

Pssm-ID: 409406 [Multi-domain] Cd Length: 82 Bit Score: 45.27 E-value: 1.06e-05

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 20127422  612 RVFIPcvvVSGDLPITITWQKDGRPIPGSLGVTIDNIDFTSSLRISNLSLMHNGNYTCIARNEAAavEHQSQLIVRV 688
Cdd:cd05748   11 RLDIP---IKGRPTPTVTWSKDGQPLKETGRVQIETTASSTSLVIKNAKRSDSGKYTLTLKNSAG--EKSATINVKV 82

Third immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the Constant 2 (C2)-set of IgSF domains; The members here are composed of the third immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. This group belongs to the C2-set of IgSF domains, having A, B, and E strands in one beta-sheet and A', G, F, C, and C' in the other. Unlike other Ig domain sets, the C2-set lacks the D strand.

Pssm-ID: 409549 [Multi-domain] Cd Length: 88 Bit Score: 45.60 E-value: 1.20e-05

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 20127422 1301 KDIVLPCKAVGDPSPAVKWMKDSNGTPSlvtiDGRRSIFSNGSFIIRTVKAEDSGYYSCIANNNWGSDEIILNLQV 1376
Cdd:cd20957   17 RTAVFNCSVTGNPIHTVLWMKDGKPLGH----SSRVQILSEDVLVIPSVKREDKGMYQCFVRNDGDSAQATAELKL 88

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor_like-1(FGFRL1); member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor like-1(FGFRL1). FGFRL1 is comprised of a signal peptide, three extracellular Ig-like modules, a transmembrane segment, and a short intracellular domain. FGFRL1 is expressed preferentially in skeletal tissues. Similar to FGF receptors, the expressed protein interacts specifically with heparin and with FGF2. FGFRL1 does not have a protein tyrosine kinase domain at its C-terminus; neither does its cytoplasmic domain appear to interact with a signaling partner. It has been suggested that FGFRL1 may not have any direct signaling function, but instead acts as a decoy receptor trapping FGFs and preventing them from binding other receptors.

Pssm-ID: 409442 Cd Length: 92 Bit Score: 45.62 E-value: 1.23e-05

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 20127422  704 GKAVILNCSAEGYPVPTIVWKFSKGAGVPQfqPIALNGRIQVlsngSLLIKHVVEEDSGYYLCKVSNDVGA 774
Cdd:cd05856   19 GSSVRLKCVASGNPRPDITWLKDNKPLTPP--EIGENKKKKW----TLSLKNLKPEDSGKYTCHVSNRAGE 83

Fifth immunoglobulin (Ig)-like domain of the carcinoembryonic antigen (CEA) related cell adhesion molecule 5 (CEACAM5) and similar domains; member of the C2-set IgSF domains; The members here are composed of the fifth immunoglobulin (Ig)-like domain of the carcinoembryonic antigen (CEA) related cell adhesion molecule 5 (CEACAM5) and similar domains. The CEA family is a group of anchored or secreted glycoproteins, expressed by epithelial cells, leukocytes, endothelial cells and placenta. The CEA family is divided into the CEACAM and pregnancy-specific glycoprotein (PSG) subfamilies. Carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5), also known as CD66e (Cluster of Differentiation 66e), is a cell surface glycoprotein that plays a role in cell adhesion, intracellular signaling and tumor progression. Diseases associated with CEACAM5 include lung cancer and rectum cancer. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. This group belongs to the C2-set of IgSF domains, having A, B, and E strands in one beta-sheet and A', G, F, C' in the other. Unlike other Ig domain sets, the C2-set lacks the D strand.

Pssm-ID: 409540 Cd Length: 76 Bit Score: 45.18 E-value: 1.25e-05

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 20127422  239 GQRVELPCKALGHPEPDYRWlkdnmplELSGRFQKTVTGLLIENIRPSDSGSYVCEVSNRyGTAKVIGRLYVKQ 312
Cdd:cd20948   10 GENLNLSCHAASNPPAQYSW-------TINGTFQTSSQELFLPAITENNEGTYTCSAHNS-LTGKNISLVLSVT 75

Immunoglobulin (Ig)-like domain of titin and similar proteins; The members here are composed of the immunoglobulin (Ig)-like domain found in titin-like proteins and similar proteins. Titin (also called connectin) is a fibrous sarcomeric protein specifically found in vertebrate striated muscle. Titin is a giant protein; depending on isoform composition, it ranges from 2970 to 3700 kDa, and is of a length that spans half a sarcomere. Titin largely consists of multiple repeats of Ig-like and fibronectin type 3 (FN-III)-like domains. Titin connects the ends of myosin thick filaments to Z disks and extends along the thick filament to the H zone. It appears to function similarly to an elastic band, keeping the myosin filaments centered in the sarcomere during muscle contraction or stretching. Within the sarcomere, titin is also attached to or is associated with myosin binding protein C (MyBP-C). MyBP-C appears to contribute to the generation of passive tension by titin and like titin has repeated Ig-like and FN-III domains. Also included in this group are worm twitchin and insect projectin, thick filament proteins of invertebrate muscle which also have repeated Ig-like and FN-III domains.

Pssm-ID: 409406 [Multi-domain] Cd Length: 82 Bit Score: 45.27 E-value: 1.27e-05

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 20127422 1310 VGDPSPAVKWMKDS--NGTPSLVTIDGRRSifsNGSFIIRTVKAEDSGYYSCIANNNWGSDEIILNLQV 1376
Cdd:cd05748   17 KGRPTPTVTWSKDGqpLKETGRVQIETTAS---STSLVIKNAKRSDSGKYTLTLKNSAGEKSATINVKV 82

Immunoglobulin (Ig)-like I-set domain of Neural Cell Adhesion Molecule 1 (NCAM-1); The members here are composed of the fourth Ig domain of Neural Cell Adhesion Molecule 1(NCAM-1). NCAM plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM) and heterophilic (NCAM-non-NCAM) interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves Ig1, Ig2, and Ig3. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions), through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain. One of the unique features of I-set domains is the lack of a C" strand. The structures of this group show that the Ig domain lacks this strand and thus is a member of the I-set of Ig domains.

Pssm-ID: 143277 [Multi-domain] Cd Length: 97 Bit Score: 45.74 E-value: 1.33e-05

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 20127422 1303 IVLPCKAVGDPSPAVKWMKDS-NGTPSLVTIDGR---RSIFSNGSFIIRTVKAEDSGYYSCIANNNWGSDEIILNLQV 1376
Cdd:cd05869   20 ITLTCEASGDPIPSITWRTSTrNISSEEKTLDGHivvRSHARVSSLTLKYIQYTDAGEYLCTASNTIGQDSQSMYLEV 97

Third immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the Constant 2 (C2)-set of IgSF domains; The members here are composed of the third immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. This group belongs to the C2-set of IgSF domains, having A, B, and E strands in one beta-sheet and A', G, F, C, and C' in the other. Unlike other Ig domain sets, the C2-set lacks the D strand.

Pssm-ID: 409549 [Multi-domain] Cd Length: 88 Bit Score: 45.22 E-value: 1.70e-05

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  125 PYTVRV--EDQKTMRGNVAVFKCIIPSSVeayITVVSWEKDTVSLVSGSRFLITSTGALYIKDVQNED-GLynYRCITRH 201
Cdd:cd20957    1 PLSATIdpPVQTVDFGRTAVFNCSVTGNP---IHTVLWMKDGKPLGHSSRVQILSEDVLVIPSVKREDkGM--YQCFVRN 75


                 ....*....
gi 20127422  202 ryTGETRQS 210
Cdd:cd20957   76 --DGDSAQA 82

Fourth immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM); The members here are composed of the fourth immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region, and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, and spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM.

Pssm-ID: 409453 [Multi-domain] Cd Length: 89 Bit Score: 44.89 E-value: 1.86e-05

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  417 VVSPAEPVSLMCNVKGTPLPTITWTLDDDPILKGGSHRISQMitSEGNVVsylnISSSQVRDGGVYRCTANNSAGVVLYQ 496
Cdd:cd05867   10 LYGPGETARLDCQVEGIPTPNITWSINGAPIEGTDPDPRRHV--SSGALI----LTDVQPSDTAVYQCEARNRHGNLLAN 83


                 ....*
gi 20127422  497 ARINV 501
Cdd:cd05867   84 AHVHV 88

Fourth immunoglobulin (Ig)-like domain in neogenin, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain in neogenin and related proteins. Neogenin is a cell surface protein which is expressed in the developing nervous system of vertebrate embryos in the growing nerve cells. It is also expressed in other embryonic tissues, and may play a general role in developmental processes such as cell migration, cell-cell recognition, and tissue growth regulation. Included in this group is the tumor suppressor protein DCC which is deleted in colorectal carcinoma. DCC and neogenin each have four Ig-like domains followed by six fibronectin type III domains, a transmembrane domain, and an intracellular domain. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409388 Cd Length: 84 Bit Score: 44.49 E-value: 2.21e-05

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  320 PRKVKSSVGSQVSLSCSVTGTEDQELSWYRNGEILNPGKNVRItgINHENLIMDHMVKSDGGAYQCFVRKDKLSAQDYVQ 399
Cdd:cd05723    4 PSNIYAHESMDIVFECEVTGKPTPTVKWVKNGDVVIPSDYFKI--VKEHNLQVLGLVKSDEGFYQCIAENDVGNAQASAQ 81


                 ...
gi 20127422  400 VVL 402
Cdd:cd05723   82 LII 84

Immunoglobulin domain; Members of the immunoglobulin superfamily are found in hundreds of proteins of different functions. Examples include antibodies, the giant muscle kinase titin and receptor tyrosine kinases. Immunoglobulin-like domains may be involved in protein-protein and protein-ligand interactions.

Pssm-ID: 395002 Cd Length: 86 Bit Score: 44.49 E-value: 2.24e-05

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422   1303 IVLPCKAV-GDPSPAVKWMK-DSNGTPSLVTIDGRRSIFSNgSFIIRTVKAEDSGYYSCIANNNWGSDEI 1370
Cdd:pfam00047   14 ATLTCSAStGSPGPDVTWSKeGGTLIESLKVKHDNGRTTQS-SLLISNVTKEDAGTYTCVVNNPGGSATL 82

Fifth Ig-like domain of Roundabout (Robo) homolog 1/2, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fifth Ig-like domain of Roundabout (Robo) homolog 1/2 and similar domains. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, -2, and -3), and three mammalian Slit homologs (Slit-1,-2, -3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, -2, and -3 are expressed by commissural neurons in the vertebrate spinal cord and Slits 1, -2, -3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of slit responsiveness, antagonizes slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be is the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. The fifth Ig-like domain of Robo 1 and 2 is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors

Pssm-ID: 409544 [Multi-domain] Cd Length: 87 Bit Score: 44.79 E-value: 2.25e-05

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 20127422  238 AGQRVELPCKALGHPEPDYRWLKDNMPLELSG-RFQKTVTGLL-IENIRPSDSGSYVCEVSNRYGTAKV 304
Cdd:cd20952   13 VGGTVVLNCQATGEPVPTISWLKDGVPLLGKDeRITTLENGSLqIKGAEKSDTGEYTCVALNLSGEATW 81

Third immunoglobulin (Ig)-like domain of peroxidasin; The members here are composed of the third immunoglobulin (Ig)-like domain in peroxidasin. Peroxidasin has a peroxidase domain and interacting extracellular motifs containing four Ig-like domains. It has been suggested that peroxidasin is secreted and has functions related to the stabilization of the extracellular matrix. It may play a part in various other important processes such as removal and destruction of cells which have undergone programmed cell death and protection of the organism against non-self.

Pssm-ID: 143222 [Multi-domain] Cd Length: 74 Bit Score: 44.16 E-value: 2.27e-05

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 20127422  518 GRDTYIHCRVIGYPYYSIKWYKNSNLLPFNHRQVAFeNNGTLKLSDVQKEvDEGEYTCNVlVQPQLSTSQSVHVTV 593
Cdd:cd05745    2 GQTVDFLCEAQGYPQPVIAWTKGGSQLSVDRRHLVL-SSGTLRISRVALH-DQGQYECQA-VNIVGSQRTVAQLTV 74

Third immunoglobulin (Ig) domain of contactin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409357 [Multi-domain] Cd Length: 88 Bit Score: 44.46 E-value: 2.68e-05

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1285 PARILTFSGTVTTPWMKDIVLPCKAVGDPSPAVKWMKdSNGTPSLVTIDGRrsifSNGSFIIRTVKAEDSGYYSCIANNN 1364
Cdd:cd04968    1 PSIKVRFPADTYALKGQTVTLECFALGNPVPQIKWRK-VDGSPSSQWEITT----SEPVLEIPNVQFEDEGTYECEAENS 75


                 ....
gi 20127422 1365 WGSD 1368
Cdd:cd04968   76 RGKD 79

Domain C2 of human cardiac Myosin Binding Protein C and similar domains; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin (Ig) Domain C2 of human cardiac Myosin Binding Protein C (MyBP-C) and similar domains. MyBP-C is a thick filament protein involved in the regulation of muscle contraction. Mutations in cardiac MyBP-C gene are the second most frequent cause of hypertrophic cardiomyopathy. MyBP-C binds to myosin with two binding sites, one at its C-terminus and another at its N-terminus. The N-terminal binding site, consisting of immunoglobulin (lg) domains C1 and C2 connected by a flexible linker, interacts with the S2 segment of myosin in a phosphorylation-regulated manner. The C1 and C2 Ig domains can bind to and activate or inhibit the thin filament. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structures of the Ig domains of MyBP-C lack this strand and thus belong to the I-set of Ig superfamily domains. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors.

Pssm-ID: 409559 Cd Length: 82 Bit Score: 44.16 E-value: 2.78e-05

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 20127422  321 RKVKSSVGSQVSLSCSVTGtEDQELSWYRNGEILNPGKNVRITGIN-HENLIMDHMVKSDGGAYQCFVRKDKLSAQDYV 398
Cdd:cd20967    5 PAVQVSKGHKIRLTVELAD-PDAEVKWYKDGQELQSSSKVIFESIGaKRTLTVQQASLADAGEYQCVAGGEKCSFELFV 82

First immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the first immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409547 Cd Length: 99 Bit Score: 44.71 E-value: 2.86e-05

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1283 KAPARILTFSGTVTTPwmkdivLPCKAVGDPSPAVKWMKdSNGTpSLVTIDGRRSIFSNGSFIIRTVKAED------SGY 1356
Cdd:cd20955    6 KEPTNRIDFSNSTGAE------IECKASGNPMPEIIWIR-SDGT-AVGDVPGLRQISSDGKLVFPPFRAEDyrqevhAQV 77

                         90
                 ....*....|.
gi 20127422 1357 YSCIANNNWGS 1367
Cdd:cd20955   78 YACLARNQFGS 88

Fifth immunoglobulin (Ig)-like domain of Kirrel (kin of irregular chiasm-like) 3, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the fifth immunoglobulin (Ig)-like domain of Kirrel (kin of irregular chiasm-like) 3 (also known as Neph2). This protein has five Ig-like domains, one transmembrane domain, and a cytoplasmic tail. Included in this group is mammalian Kirrel (also known as Neph1), Kirrel2 (also known as Neph3), and Drosophila RST (also known as irregular chiasm C-roughest) protein. These proteins contain multiple Ig domains, have properties of cell adhesion molecules, and are important in organ development.

Pssm-ID: 319310 Cd Length: 98 Bit Score: 44.83 E-value: 3.03e-05

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  787 PAMITSyPNTTLATQGQKKEMSCTAHGEKP---IIVRWeKEDRIINPEMARYLVSTKEVGEEVISTLQILPTVRED-SGF 862
Cdd:cd05758    2 PPIITA-EATQPAILGEKARLECLVFSSPPpdrIVWSW-DEGFLESGSSGRFSVETFPTEPGVISVLHISGTQRSDfQTS 79

                         90
                 ....*....|....*...
gi 20127422  863 FSCHAINSYGEDRGIIQL 880
Cdd:cd05758   80 FNCSAWNRFGEGTAIVSL 97

Immunoglobulin (Ig)-like domain of myotilin, palladin, and myopalladin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the immunoglobulin (Ig)-like domain in myotilin, palladin, and myopalladin. Myotilin, palladin, and myopalladin function as scaffolds that regulate actin organization. Myotilin and myopalladin are most abundant in skeletal and cardiac muscle; palladin is ubiquitously expressed in the organs of developing vertebrates and plays a key role in cellular morphogenesis. The three family members each interact with specific molecular partners with all three binding to alpha-actinin; In addition, palladin also binds to vasodilator-stimulated phosphoprotein (VASP) and ezrin, myotilin binds to filamin and actin, and myopalladin also binds to nebulin and cardiac ankyrin repeat protein (CARP). This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409405 [Multi-domain] Cd Length: 91 Bit Score: 44.41 E-value: 3.12e-05

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 20127422  328 GSQVSLSCSVTGTEDQELSWYRNGEILNPgkNVRITGINHEN----LIMDHMVKSDGGAYQCFVR 388
Cdd:cd05744   15 GRLCRFDCKVSGLPTPDLFWQLNGKPVRP--DSAHKMLVRENgrhsLIIEPVTKRDAGIYTCIAR 77

Immunoglobulin (Ig)-like domain of myotilin, palladin, and myopalladin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the immunoglobulin (Ig)-like domain in myotilin, palladin, and myopalladin. Myotilin, palladin, and myopalladin function as scaffolds that regulate actin organization. Myotilin and myopalladin are most abundant in skeletal and cardiac muscle; palladin is ubiquitously expressed in the organs of developing vertebrates and plays a key role in cellular morphogenesis. The three family members each interact with specific molecular partners with all three binding to alpha-actinin; In addition, palladin also binds to vasodilator-stimulated phosphoprotein (VASP) and ezrin, myotilin binds to filamin and actin, and myopalladin also binds to nebulin and cardiac ankyrin repeat protein (CARP). This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409405 [Multi-domain] Cd Length: 91 Bit Score: 44.41 E-value: 3.40e-05

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  596 PPFIQPFEFPRFSIGQRVFIPCVVvSGDLPITITWQKDGRPI-PGSLGVTIDNIDFTSSLRISNLSLMHNGNYTCIARNE 674
Cdd:cd05744    1 PHFLQAPGDLEVQEGRLCRFDCKV-SGLPTPDLFWQLNGKPVrPDSAHKMLVRENGRHSLIIEPVTKRDAGIYTCIARNR 79

                         90
                 ....*....|..
gi 20127422  675 AAAVEHQSQLIV 686
Cdd:cd05744   80 AGENSFNAELVV 91

Fourth Ig-like domain from smooth muscle myosin light chain kinase and similar domains ; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain from smooth muscle myosin light chain kinase (MYLK) and similar domains. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of this group shows that the fourth Ig-like domain from myosin light chain kinase lacks this strand and thus belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409568 [Multi-domain] Cd Length: 90 Bit Score: 44.16 E-value: 3.56e-05

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 20127422 1301 KDIVLPCKAVGDPSPAVKWMKdsNGTPslVTIDGRRSIFS--NGSFIIRTVKAEDSGYYSCIANNNWG 1366
Cdd:cd20976   17 QDFVAQCSARGKPVPRITWIR--NAQP--LQYAADRSTCEagVGELHIQDVLPEDHGTYTCLAKNAAG 80

Immunoglobulin domain; Members of the immunoglobulin superfamily are found in hundreds of proteins of different functions. Examples include antibodies, the giant muscle kinase titin and receptor tyrosine kinases. Immunoglobulin-like domains may be involved in protein-protein and protein-ligand interactions.

Pssm-ID: 395002 Cd Length: 86 Bit Score: 44.11 E-value: 3.58e-05

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 20127422    796 TTLATQGQKKEMSCTAH-GEKPIIVRWEKEDRIINPEMaRYLVSTKEVGeevISTLQILPTVREDSGFFSC 865
Cdd:pfam00047    5 TVTVLEGDSATLTCSAStGSPGPDVTWSKEGGTLIESL-KVKHDNGRTT---QSSLLISNVTKEDAGTYTC 71

Third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM); The members here are composed of the third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains, five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM.

Pssm-ID: 409460 [Multi-domain] Cd Length: 83 Bit Score: 44.13 E-value: 3.59e-05

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  796 TTLATQGQKKEMSCTAHGEKPIIVRWEKEDRIINPEMARYLVSTKevgeevisTLQILPTVREDSGFFSCHAINSYGEDR 875
Cdd:cd05876    4 SLVALRGQSLVLECIAEGLPTPTVKWLRPSGPLPPDRVKYQNHNK--------TLQLLNVGESDDGEYVCLAENSLGSAR 75


                 ....*...
gi 20127422  876 GIIQLTVQ 883
Cdd:cd05876   76 HAYYVTVE 83

Second Ig-like domain of Junctional adhesion molecule-1 (JAM1); a member of the I-set of IgSF domains; The members here are composed of the second Ig-like domain of Junctional adhesion molecule-1 (JAM1). JAM1 is an immunoglobulin superfamily (IgSF) protein with two Ig-like domains in its extracellular region; it plays a role in the formation of endothelial and epithelial tight junction and acts as a receptor for mammalian reovirus sigma-1. The IgSF is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. The two sheets are linked together by a conserved disulfide bond between B strand and F strand. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The second Ig-like domain of JAM1 is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, the A strand of the I-set is discontinuous but lacks a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors.

Pssm-ID: 409542 Cd Length: 97 Bit Score: 44.23 E-value: 3.74e-05

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 20127422  236 AMAGQRVELPCKAL-GHPEPDYRWLKDNMPL----ELSGRFQK------TVTG-LLIENIRPSDSGSYVCEVSNRYGTA 302
Cdd:cd20950    9 ATIGNRAVLTCSEPdGSPPSEYTWFKDGVVMptnpKSTRAFSNssysldPTTGeLVFDPLSASDTGEYSCEARNGYGTP 87

Immunoglobulin domain of human Synaptic Adhesion-Like Molecule 5 (SALM5) and similar proteins; member of the I-set of IgSF domains; This group contains the immunoglobulin domain of human Synaptic Adhesion-Like Molecule 5 (SALM5) and similar proteins. The SALM (for synaptic adhesion-like molecules; also known as Lrfn for leucine-rich repeat and fibronectin type III domain containing) family of adhesion molecules consists of five known members: SALM1/Lrfn2, SALM2/Lrfn1, SALM3/Lrfn4, SALM4/Lrfn3, and SALM5/Lrfn5. SALMs share a similar domain structure, containing leucine-rich repeats (LRRs), an immunoglobulin (Ig) domain, and a fibronectin III (FNIII) domain, followed by a transmembrane domain and a C-terminal PDZ-binding motif. SALM5 is implicated in autism spectrum disorders (ASDs) and schizophrenia, induces presynaptic differentiation in contacting axons. SALM5 interacts with the Ig domains of LAR (Leukocyte common Antigen-Related) family receptor protein tyrosine phosphatases (LAR-RPTPs; LAR, PTPdelta, and PTPsigma). In addition, PTPdelta is implicated in ASDs, ADHD, bipolar disorder, and restless leg syndrome. Studies have shown that LAR-RPTPs are novel and splicing-dependent presynaptic ligands for SALM5, and that they mediate SALM5-dependent presynaptic differentiation. Furthermore, SALM5 maintains AMPA receptor (AMPAR)-mediated excitatory synaptic transmission through mechanisms involving the interaction of SALM5 with LAR-RPTPs. This group belongs to the I-set of immunoglobulin superfamily (IgSF) domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409421 [Multi-domain] Cd Length: 88 Bit Score: 44.00 E-value: 3.78e-05

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  789 MITSYPNTTLATQGQKKEMSCTAHGEKPIIVRW-EKEDRIInPEMARYLVSTKevgeeviSTLQILPTVREDSGFFSCHA 867
Cdd:cd05764    2 LITRHTHELRVLEGQRATLRCKARGDPEPAIHWiSPEGKLI-SNSSRTLVYDN-------GTLDILITTVKDTGAFTCIA 73

                         90
                 ....*....|....*
gi 20127422  868 INSYGEDRGIIQLTV 882
Cdd:cd05764   74 SNPAGEATARVELHI 88

First immunoglobulin (Ig) domain of contactin-5; member of the I-set of Ig superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-5. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains, anchored to the membrane by glycosylphosphatidylinositol. The different contactins show different expression patterns in the central nervous system. In rats, a lack of contactin-5 (NB-2) results in an impairment of the neuronal activity in the auditory system. Contactin-5 is expressed specifically in the postnatal nervous system, peaking at about 3 weeks postnatal. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala; lower levels of expression have been detected in the corpus callosum, caudate nucleus, and spinal cord. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409435 Cd Length: 96 Bit Score: 44.16 E-value: 4.01e-05

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  690 PKFVVQPrdQDGIYG-----KAVILNCSAEGYPVPTIVWkFSKGAGVpqfqPIALNGRIQvLSNGSLLIKHVVE-EDSGY 763
Cdd:cd05848    2 PVFVQEP--DDAIFPtdsdeKKVILNCEARGNPVPTYRW-LRNGTEI----DTESDYRYS-LIDGNLIISNPSEvKDSGR 73

                         90
                 ....*....|....*....
gi 20127422  764 YLCKVSNDVGADVSKSMYL 782
Cdd:cd05848   74 YQCLATNSIGSILSREALL 92

Third immunoglobulin (Ig) domain of contactin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409357 [Multi-domain] Cd Length: 88 Bit Score: 44.08 E-value: 4.04e-05

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  787 PAMITSYPNTTLATQGQKKEMSCTAHGEKPIIVRWEKEDriiNPEMARYLVSTKEvgeeviSTLQILPTVREDSGFFSCH 866
Cdd:cd04968    1 PSIKVRFPADTYALKGQTVTLECFALGNPVPQIKWRKVD---GSPSSQWEITTSE------PVLEIPNVQFEDEGTYECE 71

                         90
                 ....*....|....*..
gi 20127422  867 AINSYGEDRGIIQLTVQ 883
Cdd:cd04968   72 AENSRGKDTVQGRIIVQ 88

Fourth Ig domain of the neural cell adhesion molecule contactin-2, and similar domains; The members here are composed of the fourth Ig domain of the neural cell adhesion molecule contactin-2. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-2 (also called TAG-1, axonin-1) facilitates cell adhesion by homophilic binding between molecules in apposed membranes. The first four Ig domains form the intermolecular binding fragment which arranges as a compact U-shaped module by contacts between Ig domains 1 and 4, and domains 2 and 3. It has been proposed that a linear zipper-like array forms, from contactin-2 molecules alternatively provided by the two apposed membranes.

Pssm-ID: 143205 [Multi-domain] Cd Length: 85 Bit Score: 43.74 E-value: 4.31e-05

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 20127422  608 SIGQRVFIPCVVvSGDLPITITWQKDGRPIPGSLGVTIDNidftSSLRISNLSLMHNGNYTCIARNEAAAVEHQSQLIV 686
Cdd:cd05728   12 DIGSSLRWECKA-SGNPRPAYRWLKNGQPLASENRIEVEA----GDLRITKLSLSDSGMYQCVAENKHGTIYASAELAV 85

First immunoglobulin (Ig)-like constant domain in Robo (roundabout) receptors, and similar domains; The members here are composed of the first immunoglobulin (Ig)-like domain in Roundabout (Robo) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit1, Slit2, Slit3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit1, Slit2,and Slit3 are expressed at the ventral midline. Robo3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be is the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site.

Pssm-ID: 409490 [Multi-domain] Cd Length: 99 Bit Score: 44.08 E-value: 4.44e-05

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 20127422  239 GQRVELPCKALGHPEPDYRWLKDNMPLE---LSGRFQKTVT---GLLIENIRP-----SDSGSYVCEVSNRYGTA 302
Cdd:cd07693   15 GDPATLNCKAEGRPTPTIQWLKNGQPLEtdkDDPRSHRIVLpsgSLFFLRVVHgrkgrSDEGVYVCVAHNSLGEA 89

Immunoglobulin (Ig)-like domain of NrCAM (Ng (neuronglia) CAM-related cell adhesion molecule); member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain of NrCAM (Ng (neuronglia) CAM-related cell adhesion molecule). NrCAM belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region, and an intracellular domain. NrCAM is primarily expressed in the nervous system.

Pssm-ID: 409458 Cd Length: 95 Bit Score: 44.20 E-value: 4.45e-05

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  417 VVSPAEPVSLMCNVKGTPLPTITWT-------LDDDP--ILKGGSHRISQMITSEGNVVSYlnisssqvrdGGVYRCTAN 487
Cdd:cd05874   12 IVDPRENIVIQCEAKGKPPPSFSWTrngthfdIDKDPkvTMKPNTGTLVINIMNGEKAEAY----------EGVYQCTAR 81


                 ....*..
gi 20127422  488 NSAGVVL 494
Cdd:cd05874   82 NERGAAV 88

First immunoglobulin (Ig) domain of contactin-5; member of the I-set of Ig superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-5. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains, anchored to the membrane by glycosylphosphatidylinositol. The different contactins show different expression patterns in the central nervous system. In rats, a lack of contactin-5 (NB-2) results in an impairment of the neuronal activity in the auditory system. Contactin-5 is expressed specifically in the postnatal nervous system, peaking at about 3 weeks postnatal. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala; lower levels of expression have been detected in the corpus callosum, caudate nucleus, and spinal cord. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409435 Cd Length: 96 Bit Score: 44.16 E-value: 4.46e-05

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 20127422  419 SPAEPVSLMCNVKGTPLPTITWTLDDDPILKGGSHRISQMitsEGNVVSYlniSSSQVRDGGVYRCTANNSAGVVL 494
Cdd:cd05848   17 SDEKKVILNCEARGNPVPTYRWLRNGTEIDTESDYRYSLI---DGNLIIS---NPSEVKDSGRYQCLATNSIGSIL 86

Fourth immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409548 [Multi-domain] Cd Length: 96 Bit Score: 44.09 E-value: 4.72e-05

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1284 APARILTFSGTVTTPWMkDIVLPCKAVGDPSPAVKWMKDSNGTPSL--------VTIDGRRSIFSNgsfiIRTVKAEDSG 1355
Cdd:cd20956    1 APVLLETFSEQTLQPGP-SVSLKCVASGNPLPQITWTLDGFPIPESprfrvgdyVTSDGDVVSYVN----ISSVRVEDGG 75

                         90
                 ....*....|..
gi 20127422 1356 YYSCIANNNWGS 1367
Cdd:cd20956   76 EYTCTATNDVGS 87

Fourth immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; Members here are composed the fourth immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, Robo3), and three mammalian Slit homologs (Slit-1, Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, and Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409391 [Multi-domain] Cd Length: 98 Bit Score: 44.18 E-value: 4.97e-05

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  415 EKVVSPAEPVSLMCNVKGTPLPTITWTldddpilKGGSHRI---SQMITSEGNV-VSY---LNISSSQVRDGGVYRCTAN 487
Cdd:cd05726    8 DQVVALGRTVTFQCETKGNPQPAIFWQ-------KEGSQNLlfpYQPPQPSSRFsVSPtgdLTITNVQRSDVGYYICQAL 80

                         90
                 ....*....|....*.
gi 20127422  488 NSAGVVLYQARINVRG 503
Cdd:cd05726   81 NVAGSILAKAQLEVTD 96

agrin-responsive first immunoglobulin-like domains (Ig1) of the MuSK ectodomain; a member of the I-set of IgSF domains; The members here are composed of the first immunoglobulin-like domains (Ig1) of the Muscle-specific kinase (MuSK). MuSK is a receptor tyrosine kinase specifically expressed in skeletal muscle, where it plays a central role in the formation and maintenance of the neuromuscular junction (NMJ). MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. The activation of MUSK in myotubes regulates the formation of NMJs through the regulation of different processes including the specific expression of genes in subsynaptic nuclei, the reorganization of the actin cytoskeleton and the clustering of the acetylcholine receptors (AChR) in the postsynaptic membrane. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the MuSK lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409562 [Multi-domain] Cd Length: 92 Bit Score: 43.65 E-value: 5.06e-05

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 20127422  512 NITAIAGRDTYIHCRVIGYPYYSIKWYKNSNLL-PFNHRQVAFENNGTLKLSDVQKEvDEGEYTC 575
Cdd:cd20970   11 TVTAREGENATFMCRAEGSPEPEISWTRNGNLIiEFNTRYIVRENGTTLTIRNIRRS-DMGIYLC 74

First immunoglobulin (Ig) domain of contactin; member of the I-set of (Ig) superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409356 [Multi-domain] Cd Length: 96 Bit Score: 43.77 E-value: 5.24e-05

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 20127422  419 SPAEPVSLMCNVKGTPLPTITWTLDDDPILKGGSHRISQMitsEGNVVsylnISS-SQVRDGGVYRCTANNSAGVVL 494
Cdd:cd04967   17 SDEKKVALNCRARANPVPSYRWLMNGTEIDLESDYRYSLV---DGTLV----ISNpSKAKDAGHYQCLATNTVGSVL 86

Third immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the Constant 2 (C2)-set of IgSF domains; The members here are composed of the third immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. This group belongs to the C2-set of IgSF domains, having A, B, and E strands in one beta-sheet and A', G, F, C, and C' in the other. Unlike other Ig domain sets, the C2-set lacks the D strand.

Pssm-ID: 409549 [Multi-domain] Cd Length: 88 Bit Score: 43.67 E-value: 5.32e-05

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 20127422  620 VSGDLPITITWQKDGRPIPGSLGVTIDNIDftsSLRISNLSLMHNGNYTCIARNEAAAVEHQSQL 684
Cdd:cd20957   25 VTGNPIHTVLWMKDGKPLGHSSRVQILSED---VLVIPSVKREDKGMYQCFVRNDGDSAQATAEL 86

Sixth immunoglobulin (Ig) domain of contactin; The members here are composed of the sixth immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409359 Cd Length: 102 Bit Score: 44.08 E-value: 5.80e-05

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  404 DGTpKIISAFSEKVVSPAEPVSLMCNVKGTPLP--TITWTLDDDPI---LKGGSHRISQMITSEGNvvsyLNISSSQVRD 478
Cdd:cd04970    1 DAT-RITLAPSNADITVGENATLQCHASHDPTLdlTFTWSFNGVPIdleKIEGHYRRRYGKDSNGD----LEIVNAQLKH 75

                         90       100
                 ....*....|....*....|....*.
gi 20127422  479 GGVYRCTANNSAGVVLYQARINVRGP 504
Cdd:cd04970   76 AGRYTCTAQTVVDSDSASATLVVRGP 101

First immunoglobulin (Ig) domain of contactin-2; member of the I-set of Ig superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-2-like. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-2 (TAG-1, axonin-1) facilitates cell adhesion by homophilic binding between molecules in apposed membranes. It may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module by contacts between IG domains 1 and 4, and domains 2 and 3. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-2 is also expressed in retinal amacrine cells in the developing chick retina, corresponding to the period of formation and maturation of AC processes. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409437 [Multi-domain] Cd Length: 97 Bit Score: 43.76 E-value: 5.85e-05

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 20127422  237 MAGQRVELPCKALGHPEPDYRWLKD--NMPLELSGRFQKTVTGLLIEN-IRPSDSGSYVCEVSNRYGT 301
Cdd:cd05850   18 SAEEKVTLACRARASPPATYRWKMNgtELKMEPDSRYRLVAGNLVISNpVKAKDAGSYQCLASNRRGT 85

Second Ig-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the titin Z1z2 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409564 [Multi-domain] Cd Length: 91 Bit Score: 43.73 E-value: 6.05e-05

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 20127422 1303 IVLPCKAVGDPSPAVKWMKDSNGTPSLVTIdgrrSIFSNG---SFIIRTVKAEDSGYYSCIANNNWGSD 1368
Cdd:cd20972   19 VRLECRVTGNPTPVVRWFCEGKELQNSPDI----QIHQEGdlhSLIIAEAFEEDTGRYSCLATNSVGSD 83

Fibronectin type 3 domain; One of three types of internal repeats found in the plasma protein fibronectin. Its tenth fibronectin type III repeat contains an RGD cell recognition sequence in a flexible loop between 2 strands. Approximately 2% of all animal proteins contain the FN3 repeat; including extracellular and intracellular proteins, membrane spanning cytokine receptors, growth hormone receptors, tyrosine phosphatase receptors, and adhesion molecules. FN3-like domains are also found in bacterial glycosyl hydrolases.

Pssm-ID: 238020 [Multi-domain] Cd Length: 93 Bit Score: 43.64 E-value: 6.06e-05

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 20127422 1486 SINTTRVRLNLIGWNDGGCPITSFTLEYRPFGTTVWTTAQRTSLSK-SYILYDLQEATWYELQMRVCNSAG 1555
Cdd:cd00063   11 DVTSTSVTLSWTPPEDDGGPITGYVVEYREKGSGDWKEVEVTPGSEtSYTLTGLKPGTEYEFRVRAVNGGG 81

Third immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule 1 (NCAM-1); member of the I-set of IgSF domains; The members here are composed of the third immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule (NCAM-1). NCAM plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM), and heterophilic (NCAM-non-NCAM), interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves Ig1, Ig2, and Ig3. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions) through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain.

Pssm-ID: 143207 [Multi-domain] Cd Length: 95 Bit Score: 43.77 E-value: 6.11e-05

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  422 EPVSLMCNVKGTPLPTITWTLDDDPIlKGGSHRISqmITSEGNVVSYLNISSSqvrDGGVYRCTANNSAG 491
Cdd:cd05730   19 QSVTLACDADGFPEPTMTWTKDGEPI-ESGEEKYS--FNEDGSEMTILDVDKL---DEAEYTCIAENKAG 82

Fourth immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; Members here are composed the fourth immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, Robo3), and three mammalian Slit homologs (Slit-1, Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, and Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409391 [Multi-domain] Cd Length: 98 Bit Score: 43.79 E-value: 6.16e-05

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1301 KDIVLPCKAVGDPSPAVKWMKDsnGTPSLV------TIDGRRSIFSNGSFIIRTVKAEDSGYYSCIANNNWGSdeIILNL 1374
Cdd:cd05726   15 RTVTFQCETKGNPQPAIFWQKE--GSQNLLfpyqppQPSSRFSVSPTGDLTITNVQRSDVGYYICQALNVAGS--ILAKA 90


                 ....
gi 20127422 1375 QVQV 1378
Cdd:cd05726   91 QLEV 94

Immunoglobulin (Ig)-like domain of human titin C terminus and similar proteins; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the fifth immunoglobulin (Ig)-like domain from the C-terminus of human titin x and similar proteins. Titin (also called connectin) is a fibrous sarcomeric protein specifically found in vertebrate striated muscle. Titin is gigantic; depending on isoform composition it ranges from 2970 to 3700 kDa, and is of a length that spans half a sarcomere. Titin largely consists of multiple repeats of Ig-like and fibronectin type 3 (FN-III)-like domains. Titin connects the ends of myosin thick filaments to Z disks and extends along the thick filament to the H zone and appears to function similar to an elastic band, keeping the myosin filaments centered in the sarcomere during muscle contraction or stretching. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 143224 [Multi-domain] Cd Length: 92 Bit Score: 43.50 E-value: 6.25e-05

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1285 PARILTFSGTVTTPWMKDIVLPCKAVGDPSPAVKWMKDSNgtpslVTIDGRRSIFSN----GSFIIRTVKAEDSGYYSCI 1360
Cdd:cd05747    3 PATILTKPRSLTVSEGESARFSCDVDGEPAPTVTWMREGQ-----IIVSSQRHQITSteykSTFEISKVQMSDEGNYTVV 77


                 ....*....
gi 20127422 1361 ANNNWGSDE 1369
Cdd:cd05747   78 VENSEGKQE 86

First immunoglobulin (Ig) domain of contactin-5; member of the I-set of Ig superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-5. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains, anchored to the membrane by glycosylphosphatidylinositol. The different contactins show different expression patterns in the central nervous system. In rats, a lack of contactin-5 (NB-2) results in an impairment of the neuronal activity in the auditory system. Contactin-5 is expressed specifically in the postnatal nervous system, peaking at about 3 weeks postnatal. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala; lower levels of expression have been detected in the corpus callosum, caudate nucleus, and spinal cord. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409435 Cd Length: 96 Bit Score: 43.78 E-value: 6.34e-05

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 20127422  240 QRVELPCKALGHPEPDYRWLKD--NMPLELSGRFQKTVTGLLIENirPS---DSGSYVCEVSNRYGT 301
Cdd:cd05848   20 KKVILNCEARGNPVPTYRWLRNgtEIDTESDYRYSLIDGNLIISN--PSevkDSGRYQCLATNSIGS 84

Immunoglobulin (Ig)-like domain of vascular endothelial growth factor receptor 2 (VEGFR-2); member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the immunoglobulin (Ig)-like domain of vascular endothelial growth factor receptor 2 (VEGFR-2). The VEGFRs have an extracellular component with seven Ig-like domains, a transmembrane segment, and an intracellular tyrosine kinase domain interrupted by a kinase-insert domain. VEGFRs bind VEGFs with high affinity at the Ig-like domains. VEGFR-2 (KDR/Flk-1) is a major mediator of the mitogenic, angiogenic and microvascular permeability-enhancing effects of VEGF-A; VEGF-A is important to the growth and maintenance of vascular endothelial cells and to the development of new blood- and lymphatic-vessels in physiological and pathological states. VEGF-A also interacts with VEGFR-1, which it binds more strongly than VEGFR-2. VEGFR-1 and VEGFR-2 may mediate a chemotactic and a survival signal in hematopoietic stem cells or leukemia cells. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409450 Cd Length: 89 Bit Score: 43.38 E-value: 6.49e-05

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 20127422  235 KAMAGQRVELPCKALGHPEPDYRWLKDNMPLELSGRFQKTVTgLLIENIRPSDSGSYVCEVSN 297
Cdd:cd05864   13 EAKVGERVRIPVKYLGYPPPEIKWYKNGIPIESNHTIKAGHV-LTIMEVTEKDAGNYTVVLTN 74

Second immunoglobulin (Ig)-like domain of a Follistatin-related protein 5, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain found in human Follistatin-related protein 5 (FSTL5) and a follistatin-like molecule encoded by the CNS-related Mahya gene. Mahya genes have been retained in certain Bilaterian branches during evolution. They are conserved in Hymenoptera and Deuterostomes, but are absent from other metazoan species such as fruit fly and nematode. Mahya proteins are secretory, with a follistatin-like domain (Kazal-type serine/threonine protease inhibitor domain and EF-hand calcium-binding domain), two Ig-like domains, and a novel C-terminal domain. Mahya may be involved in learning and memory and in processing of sensory information in Hymenoptera and vertebrates. Follistatin is a secreted, multidomain protein that binds activins with high affinity and antagonizes their signaling.

Pssm-ID: 409399 [Multi-domain] Cd Length: 93 Bit Score: 43.40 E-value: 6.84e-05

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  318 ISPRKVKSSVGSQVSLSCSVTGTEDQELSWYRNGEILNPGKNVRITGI-NHENLIMDHMVKSDGGAYQCFVRKDKLSAQD 396
Cdd:cd05736    5 VYPEFQAKEPGVEASLRCHAEGIPLPRVQWLKNGMDINPKLSKQLTLIaNGSELHISNVRYEDTGAYTCIAKNEGGVDED 84


                 ....*...
gi 20127422  397 YVQVVLED 404
Cdd:cd05736   85 ISSLFVED 92

Immunoglobulin (Ig)-like domain of the human basement membrane heparan sulfate proteoglycan perlecan and similar proteins; The members here are composed of the immunoglobulin (Ig)-like domain of the human basement membrane heparan sulfate proteoglycan perlecan, also known as HSPG2, and similar proteins. Perlecan consists of five domains: domain I has three putative heparan sulfate attachment sites, domain II has four LDL receptor-like repeats, and one Ig-like repeat, domain III resembles the short arm of laminin chains, domain IV has multiple Ig-like repeats (21 repeats in human perlecan), and domain V resembles the globular G domain of the laminin A chain and internal repeats of EGF. Perlecan may participate in a variety of biological functions including cell binding, LDL-metabolism, basement membrane assembly and selective permeability, calcium binding, and growth- and neurite-promoting activities.

Pssm-ID: 143220 Cd Length: 78 Bit Score: 42.86 E-value: 7.41e-05

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 20127422  704 GKAVILNCSAEGYPVPTIVWKFSKGagvpqfqPIALNGRIQVLSN---GSLLIKHVVEEDSGYYLCKVSNDVG 773
Cdd:cd05743    1 GETVEFTCVATGVPTPIINWRLNWG-------HVPDSARVSITSEggyGTLTIRDVKESDQGAYTCEAINTRG 66

Fourth immunoglobulin (Ig)-like domain in neogenin, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain in neogenin and related proteins. Neogenin is a cell surface protein which is expressed in the developing nervous system of vertebrate embryos in the growing nerve cells. It is also expressed in other embryonic tissues, and may play a general role in developmental processes such as cell migration, cell-cell recognition, and tissue growth regulation. Included in this group is the tumor suppressor protein DCC which is deleted in colorectal carcinoma. DCC and neogenin each have four Ig-like domains followed by six fibronectin type III domains, a transmembrane domain, and an intracellular domain. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409388 Cd Length: 84 Bit Score: 42.95 E-value: 7.58e-05

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 20127422 1302 DIVLPCKAVGDPSPAVKWMKDSNGT-PSlvtiDGRRSIFSNGSFIIRTVKAeDSGYYSCIANNNWGS 1367
Cdd:cd05723   14 DIVFECEVTGKPTPTVKWVKNGDVViPS----DYFKIVKEHNLQVLGLVKS-DEGFYQCIAENDVGN 75

Second C-terminal immunoglobulin (Ig)-like domain of palladin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the C-terminal immunoglobulin (Ig)-like domain of palladin. Palladin belongs to the palladin-myotilin-myopalladin family. Proteins belonging to this family contain multiple Ig-like domains and function as scaffolds, modulating actin cytoskeleton. Palladin binds to alpha-actinin ezrin, vasodilator-stimulated phosphoprotein VASP, SPIN90 (also known as DIP or mDia interacting protein), and Src. Palladin also binds F-actin directly, via its Ig3 domain. Palladin is expressed as several alternatively spliced isoforms, having various combinations of Ig-like domains, in a cell-type-specific manner. It has been suggested that palladin's different Ig-like domains may be specialized for distinct functions. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409582 Cd Length: 91 Bit Score: 43.17 E-value: 8.11e-05

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1289 LTFSGTVTTPWMKDIVLPCKAVGDPSPAVKWMKDsnGTPSLVTIDGRRSIFSNG--SFIIRTVKAEDSGYYSCIANNNWG 1366
Cdd:cd20990    4 LQAPGDLTVQEGKLCRMDCKVSGLPTPDLSWQLD--GKPIRPDSAHKMLVRENGvhSLIIEPVTSRDAGIYTCIATNRAG 81

                         90
                 ....*....|
gi 20127422 1367 SDEIILNLQV 1376
Cdd:cd20990   82 QNSFNLELVV 91

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor_like-1(FGFRL1); member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor like-1(FGFRL1). FGFRL1 is comprised of a signal peptide, three extracellular Ig-like modules, a transmembrane segment, and a short intracellular domain. FGFRL1 is expressed preferentially in skeletal tissues. Similar to FGF receptors, the expressed protein interacts specifically with heparin and with FGF2. FGFRL1 does not have a protein tyrosine kinase domain at its C-terminus; neither does its cytoplasmic domain appear to interact with a signaling partner. It has been suggested that FGFRL1 may not have any direct signaling function, but instead acts as a decoy receptor trapping FGFs and preventing them from binding other receptors.

Pssm-ID: 409442 Cd Length: 92 Bit Score: 43.31 E-value: 8.16e-05

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 20127422 1305 LPCKAVGDPSPAVKWMKDSNGTPSLVTIDGRRSIFsngSFIIRTVKAEDSGYYSCIANNNWG 1366
Cdd:cd05856   24 LKCVASGNPRPDITWLKDNKPLTPPEIGENKKKKW---TLSLKNLKPEDSGKYTCHVSNRAG 82

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor. FGF receptors bind FGF signaling polypeptides. FGFs participate in multiple processes such as morphogenesis, development, and angiogenesis. FGFs bind to four FGF receptor tyrosine kinases (FGFR1, FGFR2, FGFR3, FGFR4). Receptor diversity is controlled by alternative splicing producing splice variants with different ligand binding characteristics and different expression patterns. FGFRs have an extracellular region comprised of three IG-like domains, a single transmembrane helix, and an intracellular tyrosine kinase domain. Ligand binding and specificity reside in the Ig-like domains 2 and 3, and the linker region that connects these two. FGFR activation and signaling depend on FGF-induced dimerization, a process involving cell surface heparin or heparin sulfate proteoglycans.

Pssm-ID: 409443 [Multi-domain] Cd Length: 95 Bit Score: 43.30 E-value: 8.24e-05

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 20127422  328 GSQVSLSCSVTGTEDQELSWYRNGEILNpgKNVRITGIN----HENLIMDHMVKSDGGAYQCFV 387
Cdd:cd05857   19 ANTVKFRCPAAGNPTPTMRWLKNGKEFK--QEHRIGGYKvrnqHWSLIMESVVPSDKGNYTCVV 80

Immunoglobulin domain; This domain contains immunoglobulin-like domains.

Pssm-ID: 464026 [Multi-domain] Cd Length: 79 Bit Score: 42.77 E-value: 9.23e-05

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 20127422    326 SVGSQVSLSCSVTGTEDQELSWYRNGEILNPGKNVRITGINHEnlimdhmvksDGGAYQCFVRKDKLSAQ-DYVQVV 401
Cdd:pfam13895   12 TEGEPVTLTCSAPGNPPPSYTWYKDGSAISSSPNFFTLSVSAE----------DSGTYTCVARNGRGGKVsNPVELT 78

Sixth immunoglobulin (Ig) domain of contactin-4; The members here are composed of the sixth immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-4. Contactins are neural cell adhesion molecules, and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The different contactins show different expression patterns in the central nervous system. Highest expression of contactin-4 is in testes, thyroid, small intestine, uterus, and brain. Contactin-4 plays a role in the response of neuroblastoma cells to differentiating agents, such as retinoids. The contactin 4 gene is associated with cerebellar degeneration in spinocerebellar ataxia type 16.

Pssm-ID: 409439 Cd Length: 102 Bit Score: 43.46 E-value: 9.64e-05

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  593 VKVPPFIQPFefprfSIGQRVFIPCVVVSG-DLPITITWQKDGRPIP----GSLGVTIDNIDFTSSLRISNLSLMHNGNY 667
Cdd:cd05853    5 VMVPPSSMDV-----TVGESIVLPCQVSHDhSLDIVFTWSFNGHLIDfqkdGDHFERVGGQDSAGDLMIRSIQLKHAGKY 79

                         90       100
                 ....*....|....*....|...
gi 20127422  668 TCIARNEAAAVEHQSQLIVRVPP 690
Cdd:cd05853   80 VCMVQTSVDKLSAAADLIVRGPP 102

Immunoglobulin (Ig) domain of Down Syndrome Cell Adhesion molecule (DSCAM); The members here are composed of the immunoglobulin (Ig) domain of Down Syndrome Cell Adhesion molecule (DSCAM). DSCAM is a cell adhesion molecule expressed largely in the developing nervous system. The gene encoding DSCAM is located at human chromosome 21q22, the locus associated with the intellectual disability phenotype of Down Syndrome. DSCAM is predicted to be the largest member of the IG superfamily. It has been demonstrated that DSCAM can mediate cation-independent homophilic intercellular adhesion.

Pssm-ID: 409398 Cd Length: 101 Bit Score: 43.25 E-value: 9.71e-05

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1283 KAPARILTFSGTVTTPWMKDIVLPCKAVGDPSPAVKWMKDSNgtpslvTIDGRR------SIFSNGSFIIRTVKA----- 1351
Cdd:cd05735    1 KIPAMITSYPNTTLATKGQKKEMSCTAHGEKPIIVRWEKEDT------IINPSEmsrylvTTKEVGDEVISTLQIlptvr 74

                         90       100
                 ....*....|....*....|....*.
gi 20127422 1352 EDSGYYSCIANNNWGSDEIILNLQVQ 1377
Cdd:cd05735   75 EDSGFFSCHAINSYGEDRGIIQLTVQ 100

Immunoglobulin (Ig)-like domain of the human basement membrane heparan sulfate proteoglycan perlecan and similar proteins; The members here are composed of the immunoglobulin (Ig)-like domain of the human basement membrane heparan sulfate proteoglycan perlecan, also known as HSPG2, and similar proteins. Perlecan consists of five domains: domain I has three putative heparan sulfate attachment sites, domain II has four LDL receptor-like repeats, and one Ig-like repeat, domain III resembles the short arm of laminin chains, domain IV has multiple Ig-like repeats (21 repeats in human perlecan), and domain V resembles the globular G domain of the laminin A chain and internal repeats of EGF. Perlecan may participate in a variety of biological functions including cell binding, LDL-metabolism, basement membrane assembly and selective permeability, calcium binding, and growth- and neurite-promoting activities.

Pssm-ID: 143220 Cd Length: 78 Bit Score: 42.48 E-value: 9.85e-05

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 20127422  422 EPVSLMCNVKGTPLPTITWTLDDDPILKggSHRISqmITSEGNVVSyLNISSSQVRDGGVYRCTANNSAGVVL 494
Cdd:cd05743    2 ETVEFTCVATGVPTPIINWRLNWGHVPD--SARVS--ITSEGGYGT-LTIRDVKESDQGAYTCEAINTRGMVF 69

Fifth immunoglobulin (Ig) domain of contactin-1; The members here are composed of the fifth immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-1. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-1 is differentially expressed in tumor tissues and may through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409438 Cd Length: 89 Bit Score: 43.06 E-value: 9.87e-05

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 20127422 1303 IVLPCKAVGDPSPAVKWmkdSNGTPSLVTiDGRRSIFSNGSFIIRTVKAEDSGYYSCIANNNWG 1366
Cdd:cd05852   20 VIIECKPKAAPKPKFSW---SKGTELLVN-NSRISIWDDGSLEILNITKLDEGSYTCFAENNRG 79

Immunoglobulin I-set domain of the Leucine-rich repeat and immunoglobin-like domain-containing protein 1 (Lingo-1); The members here are composed of the immunoglobulin I-set (IgI) domain of the Leucine-rich repeat and immunoglobin-like domain-containing protein 1 (Lingo-1). Human Lingo-1 is a central nervous system-specific transmembrane glycoprotein also known as LERN-1, which functions as a negative regulator of neuronal survival, axonal regeneration, and oligodendrocyte differentiation and myelination. Lingo-1 is a key component of the Nogo receptor signaling complex (RTN4R/NGFR) in RhoA activation responsible for some inhibition of axonal regeneration by myelin-associated factors. The ligand-binding ectodomain of human Lingo-1 contains a bimodular, kinked structure composed of leucine-rich repeat (LRR) and immunoglobulin (Ig)-like modules. Diseases associated with Lingo-1 include mental retardation, autosomal recessive 64 and essential tremor. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the Lingo-1 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409561 Cd Length: 92 Bit Score: 43.15 E-value: 9.94e-05

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  418 VSPAEPVSLMCNVKGTPLPTITWtldddpiLKGGSHRISQMITSEGNVVS--YLNISSSQVRDGGVYRCTANNSAGVVLY 495
Cdd:cd20969   14 VDEGHTVQFVCRADGDPPPAILW-------LSPRKHLVSAKSNGRLTVFPdgTLEVRYAQVQDNGTYLCIAANAGGNDSM 86


                 ....*.
gi 20127422  496 QARINV 501
Cdd:cd20969   87 PAHLHV 92

Second immunoglobulin (Ig)-like domain of protein tyrosine kinase (PTK) 7; The members here are composed of the second immunoglobulin (Ig)-like domain in protein tyrosine kinase (PTK) 7, also known as CCK4. PTK7 is a subfamily of the receptor protein tyrosine kinase family, and is referred to as an RPTK-like molecule. RPTKs transduce extracellular signals across the cell membrane and play important roles in regulating cell proliferation, migration, and differentiation. PTK7 is organized as an extracellular portion having seven Ig-like domains, a single transmembrane region, and a cytoplasmic tyrosine kinase-like domain. PTK7 is considered a pseudokinase as it has several unusual residues in some of the highly conserved tyrosine kinase (TK) motifs; it is predicted to lack TK activity. PTK7 may function as a cell-adhesion molecule. PTK7 mRNA is expressed at high levels in placenta, melanocytes, liver, lung, pancreas, and kidney. PTK7 is overexpressed in several cancers, including melanoma and colon cancer lines.

Pssm-ID: 409417 Cd Length: 95 Bit Score: 42.99 E-value: 1.01e-04

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  414 SEKVVSPAEPVSLMCNVKGTPLPTITWTLDDDPILKGGSHrisqmiTSEGNVVSYLNISSSQVRDGGVYRCTANNSAGVV 493
Cdd:cd05760    9 SAAEIQPSSRVTLRCHIDGHPRPTYQWFRDGTPLSDGQGN------YSVSSKERTLTLRSAGPDDSGLYYCCAHNAFGSV 82

Fifth Ig-like domain of Roundabout (Robo) homolog 1/2, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fifth Ig-like domain of Roundabout (Robo) homolog 1/2 and similar domains. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, -2, and -3), and three mammalian Slit homologs (Slit-1,-2, -3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, -2, and -3 are expressed by commissural neurons in the vertebrate spinal cord and Slits 1, -2, -3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of slit responsiveness, antagonizes slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be is the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. The fifth Ig-like domain of Robo 1 and 2 is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors

Pssm-ID: 409544 [Multi-domain] Cd Length: 87 Bit Score: 42.87 E-value: 1.03e-04

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 20127422  609 IGQRVFIPCVVVSGDLPiTITWQKDGRPIPG--SLGVTIDNidftSSLRISNLSLMHNGNYTCIARN 673
Cdd:cd20952   13 VGGTVVLNCQATGEPVP-TISWLKDGVPLLGkdERITTLEN----GSLQIKGAEKSDTGEYTCVALN 74

C-terminal immunoglobulin (Ig)-like domain of myomesin and M-protein; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the C-terminal immunoglobulin (Ig)-like domain of myomesin and M-protein (also known as myomesin-2). Myomesin and M-protein are both structural proteins localized to the M-band, a transverse structure in the center of the sarcomere, and are candidates for M-band bridges. Both proteins are modular, consisting mainly of repetitive Ig-like and fibronectin type III (FnIII) domains. Myomesin is expressed in all types of vertebrate striated muscle; M-protein has a muscle-type specific expression pattern. Myomesin is present in both slow and fast fibers; M-protein is present only in fast fibers. It has been suggested that myomesin acts as a molecular spring with alternative splicing as a means of modifying its elasticity.

Pssm-ID: 319300 Cd Length: 92 Bit Score: 42.96 E-value: 1.03e-04

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 20127422 1301 KDIVLPCKAVGDPSPAVKWMKDSNgtpSLVTIDGRRSIFSNG---SFIIRTVKAEDSGYYSCIANNNWGSDEIILNLQV 1376
Cdd:cd05737   17 KTLNLTCNVWGDPPPEVSWLKNDQ---ALAFLDHCNLKVEAGrtvYFTINGVSSEDSGKYGLVVKNKYGSETSDVTVSV 92

Immunoglobulin (Ig)-like domain of human neurofascin (NF); member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain of human neurofascin (NF). NF belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region, and a cytoplasmic domain. NF has many alternatively spliced isoforms having different temporal expression patterns during development. NF participates in axon subcellular targeting and synapse formation, however little is known of the functions of the different isoforms. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lacks a C" strand.

Pssm-ID: 409459 Cd Length: 95 Bit Score: 43.04 E-value: 1.05e-04

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  692 FVVQPRDQdgiygkaVILNCSAEGYPVPTIVWKFSKgagvpQFQPIALNGRIQVLS-NGSLLI----KHVVEEDSGYYLC 766
Cdd:cd05875   11 YIVDPRDN-------ILIECEAKGNPVPTFHWTRNG-----KFFNVAKDPRVSMRRrSGTLVIdfrgGGRPEDYEGEYQC 78

                         90
                 ....*....|....*.
gi 20127422  767 KVSNDVGADVSKSMYL 782
Cdd:cd05875   79 FARNKFGTALSNKIRL 94

Fourth immunoglobulin (Ig)-like domain of NrCAM (NgCAM-related cell adhesion molecule); The members here are composed of the fourth immunoglobulin (Ig)-like domain of NrCAM (NgCAM-related cell adhesion molecule). NrCAM belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six IG-like domains and five fibronectin type III domains, a transmembrane region, and an intracellular domain. NrCAM is primarily expressed in the nervous system.

Pssm-ID: 409454 Cd Length: 89 Bit Score: 42.66 E-value: 1.06e-04

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 20127422  239 GQRVELPCKALGHPEPDYRWLKDNMPLELSGR-FQKTVTG--LLIENIRPSDSGSYVCEVSNRYG 300
Cdd:cd05868   14 GEDGTLICRANGNPKPSISWLTNGVPIEIAPTdPSRKVDGdtIIFSKVQERSSAVYQCNASNEYG 78

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor, and similar domains; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor. FGF receptors bind FGF signaling polypeptides. FGFs participate in multiple processes such as morphogenesis, development, and angiogenesis. FGFs bind to four FGF receptor tyrosine kinases (FGFR1, FGFR2, FGFR3, FGFR4). Receptor diversity is controlled by alternative splicing producing splice variants with different ligand binding characteristics and different expression patterns. FGFRs have an extracellular region comprised of three Ig-like domains, a single transmembrane helix, and an intracellular tyrosine kinase domain. Ligand binding and specificity reside in the Ig-like domains 2 and 3, and the linker region that connects these two. FGFR activation and signaling depend on FGF-induced dimerization, a process involving cell surface heparin or heparin sulfate proteoglycans. This group also contains fibroblast growth factor (FGF) receptor like-1(FGFRL1). FGFRL1 does not have a protein tyrosine kinase domain at its C-terminus; neither does its cytoplasmic domain appear to interact with a signaling partner. It has been suggested that FGFRL1 may not have any direct signaling function, but instead acts as a decoy receptor trapping FGFs and preventing them from binding other receptors.

Pssm-ID: 409393 [Multi-domain] Cd Length: 95 Bit Score: 42.98 E-value: 1.07e-04

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 20127422  415 EKVVSPAEPVSLMCNVKGTPLPTITWTLDDDPILKggSHRISqmITSEGNVVSYLNISSSQVRDGGVYRCTANNSAGVV 493
Cdd:cd05729   13 EHALPAANKVRLECGAGGNPMPNITWLKDGKEFKK--EHRIG--GTKVEEKGWSLIIERAIPRDKGKYTCIVENEYGSI 87

immunoglobulin-like domain of telokin and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin (Ig) domain in telokin, the C-terminal domain of myosin light chain kinase which is identical to telokin, and similar proteins. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the telokin Ig domain lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409565 [Multi-domain] Cd Length: 88 Bit Score: 42.56 E-value: 1.11e-04

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 20127422 1305 LPCKAVGDPSPAVKWMKDSNGT--PSLVTIDGRRSifSNGSFIIRTVKAEDSGYYSCIANNNWG 1366
Cdd:cd20973   17 FDCKVEGYPDPEVKWMKDDNPIveSRRFQIDQDED--GLCSLIISDVCGDDSGKYTCKAVNSLG 78

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor. FGF receptors bind FGF signaling polypeptides. FGFs participate in multiple processes such as morphogenesis, development, and angiogenesis. FGFs bind to four FGF receptor tyrosine kinases (FGFR1, FGFR2, FGFR3, FGFR4). Receptor diversity is controlled by alternative splicing producing splice variants with different ligand binding characteristics and different expression patterns. FGFRs have an extracellular region comprised of three IG-like domains, a single transmembrane helix, and an intracellular tyrosine kinase domain. Ligand binding and specificity reside in the Ig-like domains 2 and 3, and the linker region that connects these two. FGFR activation and signaling depend on FGF-induced dimerization, a process involving cell surface heparin or heparin sulfate proteoglycans.

Pssm-ID: 409443 [Multi-domain] Cd Length: 95 Bit Score: 42.92 E-value: 1.15e-04

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 20127422 1307 CKAVGDPSPAVKWMKDSNGTPSLVTIDGRRSIFSNGSFIIRTVKAEDSGYYSCIANNNWGS 1367
Cdd:cd05857   26 CPAAGNPTPTMRWLKNGKEFKQEHRIGGYKVRNQHWSLIMESVVPSDKGNYTCVVENEYGS 86

Immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM) and similar proteins; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains NrCAM [Ng(neuronglia)CAM-related cell adhesion molecule], which is primarily expressed in the nervous system, and human neurofascin. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lacks a C" strand.

Pssm-ID: 409396 [Multi-domain] Cd Length: 94 Bit Score: 42.78 E-value: 1.25e-04

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1295 VTTPWMKDIVLPCKAVGDPSPAVKWMKDsnGTPSLVTIDGRRSIFSN-GSFII--RTVKAED-SGYYSCIANNNWG---S 1367
Cdd:cd05733   11 YIVDPRDNITIKCEAKGNPQPTFRWTKD--GKFFDPAKDPRVSMRRRsGTLVIdnHNGGPEDyQGEYQCYASNELGtaiS 88


                 ....*
gi 20127422 1368 DEIIL 1372
Cdd:cd05733   89 NEIRL 93

Third immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the Constant 2 (C2)-set of IgSF domains; The members here are composed of the third immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. This group belongs to the C2-set of IgSF domains, having A, B, and E strands in one beta-sheet and A', G, F, C, and C' in the other. Unlike other Ig domain sets, the C2-set lacks the D strand.

Pssm-ID: 409549 [Multi-domain] Cd Length: 88 Bit Score: 42.52 E-value: 1.37e-04

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 20127422  517 AGRDTYIHCRVIGYPYYSIKWYKNSNLLPFNHRqVAFENNGTLKLSDVQKEvDEGEYTCNV 577
Cdd:cd20957   15 FGRTAVFNCSVTGNPIHTVLWMKDGKPLGHSSR-VQILSEDVLVIPSVKRE-DKGMYQCFV 73

Immunoglobulin (Ig)-like I-set domain of Neural Cell Adhesion Molecule 1 (NCAM-1) and similar proteins; The members here are composed of the fourth immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule (NCAM-1). NCAM plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM), and heterophilic (NCAM-non-NCAM), interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves Ig1, Ig2, and Ig3. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions), through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain. Also included in this group is NCAM-2 (also known as OCAM/mamFas II and RNCAM) NCAM-2 is differentially expressed in the developing and mature olfactory epithelium (OE). One of the unique features of I-set domains is the lack of a C" strand. The structures of this group show that the Ig domain lacks this strand and thus is a member of the I-set of Ig domains.

Pssm-ID: 409395 [Multi-domain] Cd Length: 96 Bit Score: 42.51 E-value: 1.40e-04

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 20127422  236 AMAGQRVELPCKALGHPEPDYRWLK--DNMPLE---LSGRF----QKTVTGLLIENIRPSDSGSYVCEVSNRYG 300
Cdd:cd05732   13 AVELEQITLTCEAEGDPIPEITWRRatRGISFEegdLDGRIvvrgHARVSSLTLKDVQLTDAGRYDCEASNRIG 86

Third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM), and similar domains; The members here are composed of the third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, and spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM and human neurofascin.

Pssm-ID: 409394 [Multi-domain] Cd Length: 83 Bit Score: 42.40 E-value: 1.40e-04

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 20127422 1302 DIVLPCKAVGDPSPAVKWMKDSNGTPSlvtidGRRSIFS-NGSFIIRTVKAEDSGYYSCIANNNWGS 1367
Cdd:cd05731   12 VLLLECIAEGLPTPDIRWIKLGGELPK-----GRTKFENfNKTLKIENVSEADSGEYQCTASNTMGS 73

Third immunoglobulin (Ig) domain of contactin-1; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-1. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-1 is differentially expressed in tumor tissues and may through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 143259 Cd Length: 88 Bit Score: 42.32 E-value: 1.49e-04

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 20127422 1301 KDIVLPCKAVGDPSPAVKWMKDSNGTPSLVTIDgrrsiFSNGSFIIRTVKAEDSGYYSCIANNNWGSDE 1369
Cdd:cd05851   17 QNVTLECFALGNPVPVIRWRKILEPMPATAEIS-----MSGAVLKIFNIQPEDEGTYECEAENIKGKDK 80

C-terminal immunoglobulin (Ig)-like domain of myotilin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the C-terminal immunoglobulin (Ig)-like domain of myotilin. Mytolin belongs to the palladin-myotilin-myopalladin family. Proteins belonging to the latter family contain multiple Ig-like domains and function as scaffolds, modulating the actin cytoskeleton. Myotilin is most abundant in skeletal and cardiac muscle and is involved in maintaining sarcomere integrity. It binds to alpha-actinin, filamin, and actin. Mutations in myotilin lead to muscle disorders. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409473 Cd Length: 92 Bit Score: 42.45 E-value: 1.52e-04

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  407 PKIISAFSEKVVSPAEPVSLMCNVKGTPLPTITWTLDDDpILKGGSHRISQMITSEGNVVsyLNISSSQVRDGGVYRCTA 486
Cdd:cd05892    1 PMFIQKPQNKKVLEGDPVRLECQISAIPPPQIFWKKNNE-MLQYNTDRISLYQDNCGRIC--LLIQNANKKDAGWYTVSA 77

                         90
                 ....*....|....*
gi 20127422  487 NNSAGVVLYQARINV 501
Cdd:cd05892   78 VNEAGVVSCNARLDV 92

First immunoglobulin (Ig)-like domain in neogenin, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain in neogenin and related proteins. Neogenin is a cell surface protein which is expressed in the developing nervous system of vertebrate embryos in the growing nerve cells. It is also expressed in other embryonic tissues and may play a general role in developmental processes such as cell migration, cell-cell recognition, and tissue growth regulation. Included in this group is the tumor suppressor protein DCC which is deleted in colorectal carcinoma. DCC and neogenin each have four Ig-like domains followed by six fibronectin type III domains, a transmembrane domain, and an intracellular domain. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409387 Cd Length: 97 Bit Score: 42.47 E-value: 1.76e-04

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  236 AMAGQRVELPCKALGHPEPDYRWLKDNMPLELSG--RFQKTVTG-LLIENIRPS-----DSGSYVCEVSN-RYG-----T 301
Cdd:cd05722   13 AMRGGPVVLNCSAESDPPPKIEWKKDGVLLNLVSdeRRQQLPNGsLLITSVVHSkhnkpDEGFYQCVAQNeSLGsivsrT 92


                 ...
gi 20127422  302 AKV 304
Cdd:cd05722   93 ARV 95

Third immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, and Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409390 [Multi-domain] Cd Length: 83 Bit Score: 42.00 E-value: 1.80e-04

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 20127422  610 GQRVFIPCVVvSGDLPITITWQKDGRPIP-GSLGVTIDNidftsSLRISNLSLMHNGNYTCIARNEAAAVEHQSQLIV 686
Cdd:cd05725   12 DDSAEFQCEV-GGDPVPTVRWRKEDGELPkGRYEILDDH-----SLKIRKVTAGDMGSYTCVAENMVGKIEASATLTV 83

First Ig-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the first immunoglobulin (Ig)-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the titin Z1z2 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409566 [Multi-domain] Cd Length: 93 Bit Score: 42.34 E-value: 1.84e-04

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  407 PKIISAFSEKVVSPAEPVSLMCNVKGTPLPTITWTLDDDPILKGGSHRIsQMITSEGNvvSYLNISSSQVRDGGVYRCTA 486
Cdd:cd20974    1 PVFTQPLQSVVVLEGSTATFEAHVSGKPVPEVSWFRDGQVISTSTLPGV-QISFSDGR--AKLSIPAVTKANSGRYSLTA 77

                         90
                 ....*....|....*
gi 20127422  487 NNSAGVVLYQARINV 501
Cdd:cd20974   78 TNGSGQATSTAELLV 92

Immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM) and similar proteins; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains NrCAM [Ng(neuronglia)CAM-related cell adhesion molecule], which is primarily expressed in the nervous system, and human neurofascin. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lacks a C" strand.

Pssm-ID: 409396 [Multi-domain] Cd Length: 94 Bit Score: 42.39 E-value: 1.84e-04

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  410 ISAFSEK--VVSPAEPVSLMCNVKGTPLPTITWTLDDDPILKGGSHRISQMITSEGNVVSYLNISSSQVRdgGVYRCTAN 487
Cdd:cd05733    3 ITEQSPKdyIVDPRDNITIKCEAKGNPQPTFRWTKDGKFFDPAKDPRVSMRRRSGTLVIDNHNGGPEDYQ--GEYQCYAS 80


                 ....
gi 20127422  488 NSAG 491
Cdd:cd05733   81 NELG 84

Immunoglobulin V-set domain; This domain is found in antibodies as well as neural protein P0 and CTL4 amongst others.

Pssm-ID: 462230 Cd Length: 109 Bit Score: 42.83 E-value: 1.91e-04

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422    513 ITAIAGRDTYIHCRV---IGYPYYSIKWYKN-------------SNLLPFNHRQVAFE-------NNGTLKLSDVQKEvD 569
Cdd:pfam07686    6 VTVALGGSVTLPCTYsssMSEASTSVYWYRQppgkgptfliayySNGSEEGVKKGRFSgrgdpsnGDGSLTIQNLTLS-D 84

                           90       100
                   ....*....|....*....|....
gi 20127422    570 EGEYTCNVLVQPQLSTSQSVHVTV 593
Cdd:pfam07686   85 SGTYTCAVIPSGEGVFGKGTRLTV 108

IL-beta-binding protein; Provisional

Pssm-ID: 165149 [Multi-domain] Cd Length: 326 Bit Score: 45.78 E-value: 1.95e-04

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422   707 VILNCS-----AEGYPVPTIVWKfSKGAGvpqfqpialNGRIQVLSNGS-LLIKHVVEEDSGYYLCKVSNDVGADVsksM 780
Cdd:PHA02785   44 VILPCPqintlSSGYNILDILWE-KRGAD---------NDRIIPIDNGSnMLILNPTQSDSGIYICITKNETYCDM---M 110

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422   781 YLTVKIPAM------ITSYPNttLATQGQKKEMSC-------TAHGEKPIIvrWEKEDRIINpemarylvstKEVGEEVI 847
Cdd:PHA02785  111 SLNLTIVSVsesnidLISYPQ--IVNERSTGEMVCpninafiASNVNADII--WSGHRRLRN----------KRLKQRTP 176

                         170       180       190       200       210
                  ....*....|....*....|....*....|....*....|....*....|...
gi 20127422   848 STLQILPTVREDSGFFSCHAINSYGED----RGIIQLTVQEPPDPPEIEIKDV 896
Cdd:PHA02785  177 GIITIEDVRKNDAGYYTCVLKYIYGDKtynvTRIVKLEVRDRIIPPTMQLPEG 229

Second immunoglobulin (Ig)-like domain of the receptor protein tyrosine phosphatase (RPTP)-F; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain found in the receptor protein tyrosine phosphatase (RPTP)-F, also known as LAR. LAR belongs to the RPTP type IIa subfamily. Members of this subfamily are cell adhesion molecule-like proteins involved in central nervous system (CNS) development. They have large extracellular portions comprised of multiple Ig-like domains and two to nine fibronectin type III (FNIII) domains and a cytoplasmic portion having two tandem phosphatase domains.

Pssm-ID: 409400 [Multi-domain] Cd Length: 91 Bit Score: 42.31 E-value: 2.00e-04

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 20127422 1307 CKAVGDPSPAVKWMKDSngTP-SLVTIDGRRSIFSNGSFIIRTVKAEDSGYYSCIANNNWGS 1367
Cdd:cd05738   21 CAASGNPDPEISWFKDF--LPvDTATSNGRIKQLRSGALQIENSEESDQGKYECVATNSAGT 80

Immunoglobulin domain I1 of the titin I-band and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin domain I1 of the titin I-band and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. The two sheets are linked together by a conserved disulfide bond between B strand and F strand. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The Ig I1 domain of the titin I-band is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409543 [Multi-domain] Cd Length: 94 Bit Score: 42.02 E-value: 2.07e-04

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  328 GSQVSLSCSVTGTEDQELSWYRNGEILNPGKNVRITGINHEN----LIMDHMVKSDGGAYQCFVRKDKLSAQDYVQVVLE 403
Cdd:cd20951   15 KSDAKLRVEVQGKPDPEVKWYKNGVPIDPSSIPGKYKIESEYgvhvLHIRRVTVEDSAVYSAVAKNIHGEASSSASVVVE 94

Immunoglobulin (Ig)-like ectodomain of the LRIG1 (Leucine-rich Repeats And Immunoglobulin-like Domains Protein 1) and similar proteins; member of the I-set of IgSF domains; The members here are composed of subgroup of the immunoglobulin (Ig) domain found in the Ig superfamily. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. The ectodomain of LRIG1 has two distinct regions: the proposed 15 LRRs and three Ig-like domains closer to the membrane. LRIG1 has been reported to interact with many receptor tyrosine kinases, GDNF/c-Ret, E-cadherin, JAK/STAT, c-Met, and the EGFR family signaling systems. Immunoglobulin Superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The structure of the LRIG1 extracellular Ig domain lacks a C" strand and thus is better described as a member of the I-set of IgSF domains.

Pssm-ID: 409420 [Multi-domain] Cd Length: 91 Bit Score: 42.22 E-value: 2.08e-04

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 20127422  426 LMCNVKGTPLPTITWTLDDDPILKGGSHRISQMITSEgnvvSYLNISSSQVRDGGVYRCTANNSAGVVLYQARINV 501
Cdd:cd05763   19 LECAATGHPTPQIAWQKDGGTDFPAARERRMHVMPED----DVFFIVDVKIEDTGVYSCTAQNSAGSISANATLTV 90

Immunoglobulin (Ig)-like I-set domain of Neural Cell Adhesion Molecule 1 (NCAM-1) and similar proteins; The members here are composed of the fourth immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule (NCAM-1). NCAM plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM), and heterophilic (NCAM-non-NCAM), interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves Ig1, Ig2, and Ig3. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions), through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain. Also included in this group is NCAM-2 (also known as OCAM/mamFas II and RNCAM) NCAM-2 is differentially expressed in the developing and mature olfactory epithelium (OE). One of the unique features of I-set domains is the lack of a C" strand. The structures of this group show that the Ig domain lacks this strand and thus is a member of the I-set of Ig domains.

Pssm-ID: 409395 [Multi-domain] Cd Length: 96 Bit Score: 42.13 E-value: 2.21e-04

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  407 PKIISaFSEKVVSPAEPVSLMCNVKGTPLPTITWTLDDDPILKGGSHRISQMITSEGNVVSYLNISSSQVRDGGVYRCTA 486
Cdd:cd05732    3 PKITY-LENQTAVELEQITLTCEAEGDPIPEITWRRATRGISFEEGDLDGRIVVRGHARVSSLTLKDVQLTDAGRYDCEA 81


                 ....*.
gi 20127422  487 NNSAGV 492
Cdd:cd05732   82 SNRIGG 87

First immunoglobulin (Ig)-like constant domain in Robo (roundabout) receptors, and similar domains; The members here are composed of the first immunoglobulin (Ig)-like domain in Roundabout (Robo) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, and Robo3), and three mammalian Slit homologs (Slit1, Slit2, Slit3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit1, Slit2,and Slit3 are expressed at the ventral midline. Robo3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be is the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site.

Pssm-ID: 409490 [Multi-domain] Cd Length: 99 Bit Score: 42.15 E-value: 2.24e-04

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1287 RILTFSGTVTTPWMKDIVLPCKAVGDPSPAVKWMKdsNGTPsLVT----IDGRRSIFSNGS-FIIRTVKA----EDSGYY 1357
Cdd:cd07693    2 RIVEHPSDLIVSKGDPATLNCKAEGRPTPTIQWLK--NGQP-LETdkddPRSHRIVLPSGSlFFLRVVHGrkgrSDEGVY 78


                 ....*....
gi 20127422 1358 SCIANNNWG 1366
Cdd:cd07693   79 VCVAHNSLG 87

Immunoglobulin domain of human Synaptic Adhesion-Like Molecule 5 (SALM5) and similar proteins; member of the I-set of IgSF domains; This group contains the immunoglobulin domain of human Synaptic Adhesion-Like Molecule 5 (SALM5) and similar proteins. The SALM (for synaptic adhesion-like molecules; also known as Lrfn for leucine-rich repeat and fibronectin type III domain containing) family of adhesion molecules consists of five known members: SALM1/Lrfn2, SALM2/Lrfn1, SALM3/Lrfn4, SALM4/Lrfn3, and SALM5/Lrfn5. SALMs share a similar domain structure, containing leucine-rich repeats (LRRs), an immunoglobulin (Ig) domain, and a fibronectin III (FNIII) domain, followed by a transmembrane domain and a C-terminal PDZ-binding motif. SALM5 is implicated in autism spectrum disorders (ASDs) and schizophrenia, induces presynaptic differentiation in contacting axons. SALM5 interacts with the Ig domains of LAR (Leukocyte common Antigen-Related) family receptor protein tyrosine phosphatases (LAR-RPTPs; LAR, PTPdelta, and PTPsigma). In addition, PTPdelta is implicated in ASDs, ADHD, bipolar disorder, and restless leg syndrome. Studies have shown that LAR-RPTPs are novel and splicing-dependent presynaptic ligands for SALM5, and that they mediate SALM5-dependent presynaptic differentiation. Furthermore, SALM5 maintains AMPA receptor (AMPAR)-mediated excitatory synaptic transmission through mechanisms involving the interaction of SALM5 with LAR-RPTPs. This group belongs to the I-set of immunoglobulin superfamily (IgSF) domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409421 [Multi-domain] Cd Length: 88 Bit Score: 41.69 E-value: 2.33e-04

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  407 PKIISAFSEKVVSPAEPVSLMCNVKGTPLPTITWTLDDDPILKGGSHRIsqmITSEGNvvsyLNISSSQVRDGGVYRCTA 486
Cdd:cd05764    1 PLITRHTHELRVLEGQRATLRCKARGDPEPAIHWISPEGKLISNSSRTL---VYDNGT----LDILITTVKDTGAFTCIA 73


                 ....*
gi 20127422  487 NNSAG 491
Cdd:cd05764   74 SNPAG 78

Third immunoglobulin (Ig)-like domain in Robo (roundabout) receptors; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig)-like domain in Robo (roundabout) receptors. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, Robo2, Robo3), and three mammalian Slit homologs (Slit-1,Slit-2, Slit-3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, Robo2, and Robo3 are expressed by commissural neurons in the vertebrate spinal cord and Slit-1, Slit-2, and Slit-3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of Slit responsiveness, antagonizes Slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409390 [Multi-domain] Cd Length: 83 Bit Score: 41.61 E-value: 2.42e-04

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  414 SEKVVSPAEPVSLMCNVKGTPLPTITWTLDDDPILKGGSHrisqmITSEGNvvsyLNISSSQVRDGGVYRCTANNSAGVV 493
Cdd:cd05725    5 QNQVVLVDDSAEFQCEVGGDPVPTVRWRKEDGELPKGRYE-----ILDDHS----LKIRKVTAGDMGSYTCVAENMVGKI 75


                 ....*...
gi 20127422  494 LYQARINV 501
Cdd:cd05725   76 EASATLTV 83

Sixth immunoglobulin (Ig) domain of contactin; The members here are composed of the sixth immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409359 Cd Length: 102 Bit Score: 42.15 E-value: 2.50e-04

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  608 SIGQRVFIPCVVvSGD--LPITITWQKDGRPI----PGSLGVTIDNIDFTSSLRISNLSLMHNGNYTCIARNEAAAVEHQ 681
Cdd:cd04970   15 TVGENATLQCHA-SHDptLDLTFTWSFNGVPIdlekIEGHYRRRYGKDSNGDLEIVNAQLKHAGRYTCTAQTVVDSDSAS 93


                 ....*....
gi 20127422  682 SQLIVRVPP 690
Cdd:cd04970   94 ATLVVRGPP 102

Immunoglobulin domain of human Synaptic Adhesion-Like Molecule 5 (SALM5) and similar proteins; member of the I-set of IgSF domains; This group contains the immunoglobulin domain of human Synaptic Adhesion-Like Molecule 5 (SALM5) and similar proteins. The SALM (for synaptic adhesion-like molecules; also known as Lrfn for leucine-rich repeat and fibronectin type III domain containing) family of adhesion molecules consists of five known members: SALM1/Lrfn2, SALM2/Lrfn1, SALM3/Lrfn4, SALM4/Lrfn3, and SALM5/Lrfn5. SALMs share a similar domain structure, containing leucine-rich repeats (LRRs), an immunoglobulin (Ig) domain, and a fibronectin III (FNIII) domain, followed by a transmembrane domain and a C-terminal PDZ-binding motif. SALM5 is implicated in autism spectrum disorders (ASDs) and schizophrenia, induces presynaptic differentiation in contacting axons. SALM5 interacts with the Ig domains of LAR (Leukocyte common Antigen-Related) family receptor protein tyrosine phosphatases (LAR-RPTPs; LAR, PTPdelta, and PTPsigma). In addition, PTPdelta is implicated in ASDs, ADHD, bipolar disorder, and restless leg syndrome. Studies have shown that LAR-RPTPs are novel and splicing-dependent presynaptic ligands for SALM5, and that they mediate SALM5-dependent presynaptic differentiation. Furthermore, SALM5 maintains AMPA receptor (AMPAR)-mediated excitatory synaptic transmission through mechanisms involving the interaction of SALM5 with LAR-RPTPs. This group belongs to the I-set of immunoglobulin superfamily (IgSF) domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409421 [Multi-domain] Cd Length: 88 Bit Score: 41.69 E-value: 2.52e-04

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 20127422  233 HRKAMAGQRVELPCKALGHPEPDYRWLK-DNMPLELSGR---FQKTVTGLLIENIRpsDSGSYVCEVSNRYGTA 302
Cdd:cd05764    9 ELRVLEGQRATLRCKARGDPEPAIHWISpEGKLISNSSRtlvYDNGTLDILITTVK--DTGAFTCIASNPAGEA 80

Second immunoglobulin (Ig)-like domain of protein tyrosine kinase (PTK) 7; The members here are composed of the second immunoglobulin (Ig)-like domain in protein tyrosine kinase (PTK) 7, also known as CCK4. PTK7 is a subfamily of the receptor protein tyrosine kinase family, and is referred to as an RPTK-like molecule. RPTKs transduce extracellular signals across the cell membrane and play important roles in regulating cell proliferation, migration, and differentiation. PTK7 is organized as an extracellular portion having seven Ig-like domains, a single transmembrane region, and a cytoplasmic tyrosine kinase-like domain. PTK7 is considered a pseudokinase as it has several unusual residues in some of the highly conserved tyrosine kinase (TK) motifs; it is predicted to lack TK activity. PTK7 may function as a cell-adhesion molecule. PTK7 mRNA is expressed at high levels in placenta, melanocytes, liver, lung, pancreas, and kidney. PTK7 is overexpressed in several cancers, including melanoma and colon cancer lines.

Pssm-ID: 409417 Cd Length: 95 Bit Score: 41.84 E-value: 2.68e-04

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 20127422  241 RVELPCKALGHPEPDYRWLKDNMPLElSGRFQKTVTG----LLIENIRPSDSGSYVCEVSNRYGTA 302
Cdd:cd05760   18 RVTLRCHIDGHPRPTYQWFRDGTPLS-DGQGNYSVSSkertLTLRSAGPDDSGLYYCCAHNAFGSV 82

Immunoglobulin (Ig)-like domain of Down Syndrome Cell Adhesion molecule (DSCAM); The members here are composed of the immunoglobulin (Ig)-like domain of Down Syndrome Cell Adhesion molecule (DSCAM). DSCAM is a cell adhesion molecule expressed largely in the developing nervous system. The gene encoding DSCAM is located at human chromosome 21q22, the locus associated with the intellectual disability phenotype of Down Syndrome. DSCAM is predicted to be the largest member of the IG superfamily. It has been demonstrated that DSCAM can mediate cation-independent homophilic intercellular adhesion.

Pssm-ID: 409397 [Multi-domain] Cd Length: 97 Bit Score: 41.71 E-value: 2.81e-04

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 20127422  239 GQRVELPCKALGHPEPDYRWL--------KDNMPLELSGRFQKTVTG-LLIENIRPSDSGSYVCEVSNRYGT 301
Cdd:cd05734   16 GKAVVLNCSADGYPPPTIVWKhskgsgvpQFQHIVPLNGRIQLLSNGsLLIKHVLEEDSGYYLCKVSNDVGA 87

Fourth immunoglobulin (Ig)-like domain of NrCAM (NgCAM-related cell adhesion molecule); The members here are composed of the fourth immunoglobulin (Ig)-like domain of NrCAM (NgCAM-related cell adhesion molecule). NrCAM belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six IG-like domains and five fibronectin type III domains, a transmembrane region, and an intracellular domain. NrCAM is primarily expressed in the nervous system.

Pssm-ID: 409454 Cd Length: 89 Bit Score: 41.51 E-value: 3.17e-04

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 20127422 1301 KDIVLPCKAVGDPSPAVKWMkdSNGTPSLVT-------IDGRRSIFSNgsfiirtVKAEDSGYYSCIANNNWG 1366
Cdd:cd05868   15 EDGTLICRANGNPKPSISWL--TNGVPIEIAptdpsrkVDGDTIIFSK-------VQERSSAVYQCNASNEYG 78

Fifth immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fifth immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409550 [Multi-domain] Cd Length: 89 Bit Score: 41.40 E-value: 3.23e-04

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 20127422   44 VPCPAAGIPPVTLRWYLAtGEEIydvP-GIRH-VHPNGTLQIFPFPPSSfstliHDNTYYCTAENPSGKIRSQDVHIK 119
Cdd:cd20958   20 LHCPVAGYPISSITWEKD-GRRL---PlNHRQrVFPNGTLVIENVQRSS-----DEGEYTCTARNQQGQSASRSVFVK 88

Immunoglobulin (Ig)-like domain of titin and similar proteins; The members here are composed of the immunoglobulin (Ig)-like domain found in titin-like proteins and similar proteins. Titin (also called connectin) is a fibrous sarcomeric protein specifically found in vertebrate striated muscle. Titin is a giant protein; depending on isoform composition, it ranges from 2970 to 3700 kDa, and is of a length that spans half a sarcomere. Titin largely consists of multiple repeats of Ig-like and fibronectin type 3 (FN-III)-like domains. Titin connects the ends of myosin thick filaments to Z disks and extends along the thick filament to the H zone. It appears to function similarly to an elastic band, keeping the myosin filaments centered in the sarcomere during muscle contraction or stretching. Within the sarcomere, titin is also attached to or is associated with myosin binding protein C (MyBP-C). MyBP-C appears to contribute to the generation of passive tension by titin and like titin has repeated Ig-like and FN-III domains. Also included in this group are worm twitchin and insect projectin, thick filament proteins of invertebrate muscle which also have repeated Ig-like and FN-III domains.

Pssm-ID: 409406 [Multi-domain] Cd Length: 82 Bit Score: 41.04 E-value: 3.31e-04

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 20127422  715 GYPVPTIVWKfsKGAgvpqfQPIALNGRIQV---LSNGSLLIKHVVEEDSGYYLCKVSNDVGadvSKSMYLTVKI 786
Cdd:cd05748   18 GRPTPTVTWS--KDG-----QPLKETGRVQIettASSTSLVIKNAKRSDSGKYTLTLKNSAG---EKSATINVKV 82

Immunoglobulin V-set domain; This domain is found in antibodies as well as neural protein P0 and CTL4 amongst others.

Pssm-ID: 462230 Cd Length: 109 Bit Score: 42.06 E-value: 3.38e-04

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422    694 VQPRDQDGIYGKAVILNC---SAEGYPVPTIVWKFSKGAGVPQF---------QPIALNGRIQVL-----SNGSLLIKHV 756
Cdd:pfam07686    1 QTPREVTVALGGSVTLPCtysSSMSEASTSVYWYRQPPGKGPTFliayysngsEEGVKKGRFSGRgdpsnGDGSLTIQNL 80

                           90       100
                   ....*....|....*....|....*...
gi 20127422    757 VEEDSGYYLCKVSNDVGADVSKSMYLTV 784
Cdd:pfam07686   81 TLSDSGTYTCAVIPSGEGVFGKGTRLTV 108

Fourth immunoglobulin (Ig)-like domain of peroxidasin; The members here are composed of the fourth immunoglobulin (Ig)-like domain in peroxidasin. Peroxidasin has a peroxidase domain and interacting extracellular motifs containing four Ig-like domains. It has been suggested that peroxidasin is secreted, and has functions related to the stabilization of the extracellular matrix. It may play a part in various other important processes such as removal and destruction of cells which have undergone programmed cell death and protection of the organism against non-self.

Pssm-ID: 143223 Cd Length: 69 Bit Score: 40.63 E-value: 3.84e-04

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 20127422  707 VILNCSAEGYPVPTIVWKfSKGAGVPQfqpialNGRIQVLSNGSLLIKHVVEEDSGYYLCKVSNDVGAdVSKSMYLT 783
Cdd:cd05746    1 VQIPCSAQGDPEPTITWN-KDGVQVTE------SGKFHISPEGYLAIRDVGVADQGRYECVARNTIGY-ASVSMVLS 69

Sixth immunoglobulin (Ig) domain of contactin-2; The members here are composed of the sixth immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-2-like. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-2 (TAG-1, axonin-1) facilitates cell adhesion by homophilic binding between molecules in apposed membranes. It may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module by contacts between IG domains 1 and 4, and domains 2 and 3. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-2 is also expressed in retinal amacrine cells (AC) in the developing chick retina, corresponding to the period of formation and maturation of AC processes.

Pssm-ID: 409440 Cd Length: 102 Bit Score: 41.57 E-value: 3.91e-04

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 20127422  626 ITITWQKDGRPI----PGSLGVTIDNIDFTSSLRISNLSLMHNGNYTCIARNEAAAVEHQSQLIVRVPP 690
Cdd:cd05854   34 LTFTWSLDDFPIdldkPNGHYRRMEVKETIGDLVIVNAQLSHAGTYTCTAQTVVDSASASATLVVRGPP 102

Third immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the Constant 2 (C2)-set of IgSF domains; The members here are composed of the third immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. This group belongs to the C2-set of IgSF domains, having A, B, and E strands in one beta-sheet and A', G, F, C, and C' in the other. Unlike other Ig domain sets, the C2-set lacks the D strand.

Pssm-ID: 409549 [Multi-domain] Cd Length: 88 Bit Score: 41.36 E-value: 3.91e-04

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 20127422  238 AGQRVELPCKALGHPEPDYRWLKDNMPLELSGRFQKTVTGLL-IENIRPSDSGSYVCEVSNRYGTAKVIGRL 308
Cdd:cd20957   15 FGRTAVFNCSVTGNPIHTVLWMKDGKPLGHSSRVQILSEDVLvIPSVKREDKGMYQCFVRNDGDSAQATAEL 86

Second C-terminal immunoglobulin (Ig)-like domain of palladin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the C-terminal immunoglobulin (Ig)-like domain of palladin. Palladin belongs to the palladin-myotilin-myopalladin family. Proteins belonging to this family contain multiple Ig-like domains and function as scaffolds, modulating actin cytoskeleton. Palladin binds to alpha-actinin ezrin, vasodilator-stimulated phosphoprotein VASP, SPIN90 (also known as DIP or mDia interacting protein), and Src. Palladin also binds F-actin directly, via its Ig3 domain. Palladin is expressed as several alternatively spliced isoforms, having various combinations of Ig-like domains, in a cell-type-specific manner. It has been suggested that palladin's different Ig-like domains may be specialized for distinct functions. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409582 Cd Length: 91 Bit Score: 41.24 E-value: 4.06e-04

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  690 PKFVVQPRDQDGIYGKAVILNCSAEGYPVPTIVWKFSkgaGVPqFQPIALNgRIQVLSNG--SLLIKHVVEEDSGYYLCK 767
Cdd:cd20990    1 PHFLQAPGDLTVQEGKLCRMDCKVSGLPTPDLSWQLD---GKP-IRPDSAH-KMLVRENGvhSLIIEPVTSRDAGIYTCI 75

                         90
                 ....*....|....*..
gi 20127422  768 VSNDVGADvSKSMYLTV 784
Cdd:cd20990   76 ATNRAGQN-SFNLELVV 91

C-terminal immunoglobulin-like domain of the myosin-associated giant protein kinase Twitchin, and similar domains; member of the I-set IgSF domains; The members here are composed of the C-terminal immunoglobulin-like domain of the myosin-associated giant protein kinase Twitchin and similar proteins, including Caenorhabditis elegans and Aplysia californica Twitchin, Drosophila melanogaster Projectin, and similar proteins. These are very large muscle proteins containing multiple immunoglobulin (Ig)-like and fibronectin type III (FN3) domains and a single kinase domain near the C-terminus. In humans these proteins are called Titin. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The Ig-like domain of the Twitchin is a member of the I-set IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins (titin, telokin, and twitchin), the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D.

Pssm-ID: 409541 [Multi-domain] Cd Length: 89 Bit Score: 41.16 E-value: 4.08e-04

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 20127422  418 VSPAEPVSLMCNVKGTPLPTITWTLDDDPILKGGSHRISQMITSEGnvvsyLNISSSQVRDGGVYRCTANNSAGV 492
Cdd:cd20949   11 VKEGQSATILCEVKGEPQPNVTWHFNGQPISASVADMSKYRILADG-----LLINKVTQDDTGEYTCRAYQVNSI 80

Second immunoglobulin (Ig)-like domain of a Follistatin-related protein 5, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain found in human Follistatin-related protein 5 (FSTL5) and a follistatin-like molecule encoded by the CNS-related Mahya gene. Mahya genes have been retained in certain Bilaterian branches during evolution. They are conserved in Hymenoptera and Deuterostomes, but are absent from other metazoan species such as fruit fly and nematode. Mahya proteins are secretory, with a follistatin-like domain (Kazal-type serine/threonine protease inhibitor domain and EF-hand calcium-binding domain), two Ig-like domains, and a novel C-terminal domain. Mahya may be involved in learning and memory and in processing of sensory information in Hymenoptera and vertebrates. Follistatin is a secreted, multidomain protein that binds activins with high affinity and antagonizes their signaling.

Pssm-ID: 409399 [Multi-domain] Cd Length: 93 Bit Score: 41.09 E-value: 4.33e-04

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  593 VKVPPFIQPFEfprfsIGQRVFIPCVVVSGDLPiTITWQKDGRPIPGSLGVTIDNIDFTSSLRISNLSLMHNGNYTCIAR 672
Cdd:cd05736    3 IRVYPEFQAKE-----PGVEASLRCHAEGIPLP-RVQWLKNGMDINPKLSKQLTLIANGSELHISNVRYEDTGAYTCIAK 76

                         90
                 ....*....|....
gi 20127422  673 NEAAAVEHQSQLIV 686
Cdd:cd05736   77 NEGGVDEDISSLFV 90

C-terminal immunoglobulin-like domain of the myosin-associated giant protein kinase Twitchin, and similar domains; member of the I-set IgSF domains; The members here are composed of the C-terminal immunoglobulin-like domain of the myosin-associated giant protein kinase Twitchin and similar proteins, including Caenorhabditis elegans and Aplysia californica Twitchin, Drosophila melanogaster Projectin, and similar proteins. These are very large muscle proteins containing multiple immunoglobulin (Ig)-like and fibronectin type III (FN3) domains and a single kinase domain near the C-terminus. In humans these proteins are called Titin. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The Ig-like domain of the Twitchin is a member of the I-set IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins (titin, telokin, and twitchin), the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D.

Pssm-ID: 409541 [Multi-domain] Cd Length: 89 Bit Score: 41.16 E-value: 4.33e-04

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 20127422 1301 KDIVLPCKAVGDPSPAVKWMKDSNGTPSLVTIDGRRSIFSNGsFIIRTVKAEDSGYYSCIANNNWGSDEIILNLQV 1376
Cdd:cd20949   15 QSATILCEVKGEPQPNVTWHFNGQPISASVADMSKYRILADG-LLINKVTQDDTGEYTCRAYQVNSIASDMQERTV 89

Immunoglobulin (Ig)-like domain in neuregulins; The members here are composed of the immunoglobulin (Ig)-like domain in neuregulins (NRGs). NRGs are signaling molecules which participate in cell-cell interactions in the nervous system, breast, heart, and other organ systems, and are implicated in the pathology of diseases including schizophrenia, multiple sclerosis, and breast cancer. There are four members of the neuregulin gene family (NRG-1, NRG-2, NRG-3, and NRG-4). The NRG-1 protein, binds to and activates the tyrosine kinases receptors ErbB3 and ErbB4, initiating signaling cascades. The other NRGs proteins bind one or the other or both of these ErbBs. NRG-1 has multiple functions: in the brain it regulates various processes such as radial glia formation and neuronal migration, dendritic development, and expression of neurotransmitters receptors, while in the peripheral nervous system NRG-1 regulates processes such as target cell differentiation, and Schwann cell survival. There are many NRG-1 isoforms which arise from the alternative splicing of mRNA. Less is known of the functions of the other NRGs. NRG-2 and NRG-3 are expressed predominantly in the nervous system. NRG-2 is expressed by motor neurons and terminal Schwann cells, and is concentrated near synaptic sites and may be a signal that regulates synaptic differentiation. NRG-4 has been shown to direct pancreatic islet cell development towards the delta-cell lineage.

Pssm-ID: 409408 [Multi-domain] Cd Length: 92 Bit Score: 41.34 E-value: 4.33e-04

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  697 RDQDGIYGKAVILNCSAEG-YPVPTIVWkFSKGAGVPQFQPIAL---NGRiqvlSNGSLLIKHVVEEDSGYYLCKVSNDV 772
Cdd:cd05750    7 KSQTVQEGSKLVLKCEATSeNPSPRYRW-FKDGKELNRKRPKNIkirNKK----KNSELQINKAKLEDSGEYTCVVENIL 81


                 ....*..
gi 20127422  773 GADVSKS 779
Cdd:cd05750   82 GKDTVTG 88

First immunoglobulin (Ig) domain of contactin; member of the I-set of (Ig) superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409356 [Multi-domain] Cd Length: 96 Bit Score: 41.07 E-value: 4.53e-04

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  690 PKFVVQPRD----QDGIYGKaVILNCSAEGYPVPTIVWKFSKGAgvpqfQPIALNGRIQvLSNGSLLIKHVVE-EDSGYY 764
Cdd:cd04967    2 PVFEEQPDDtifpEDSDEKK-VALNCRARANPVPSYRWLMNGTE-----IDLESDYRYS-LVDGTLVISNPSKaKDAGHY 74

                         90
                 ....*....|....*...
gi 20127422  765 LCKVSNDVGADVSKSMYL 782
Cdd:cd04967   75 QCLATNTVGSVLSREATL 92

Second immunoglobulin (Ig)-like domain of a Follistatin-related protein 5, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the second immunoglobulin (Ig)-like domain found in human Follistatin-related protein 5 (FSTL5) and a follistatin-like molecule encoded by the CNS-related Mahya gene. Mahya genes have been retained in certain Bilaterian branches during evolution. They are conserved in Hymenoptera and Deuterostomes, but are absent from other metazoan species such as fruit fly and nematode. Mahya proteins are secretory, with a follistatin-like domain (Kazal-type serine/threonine protease inhibitor domain and EF-hand calcium-binding domain), two Ig-like domains, and a novel C-terminal domain. Mahya may be involved in learning and memory and in processing of sensory information in Hymenoptera and vertebrates. Follistatin is a secreted, multidomain protein that binds activins with high affinity and antagonizes their signaling.

Pssm-ID: 409399 [Multi-domain] Cd Length: 93 Bit Score: 41.09 E-value: 4.91e-04

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  790 ITSYPNTTLATQGQKKEMSCTAHGEKPIIVRWEKEDRIINPEMARYLVSTKEVGEEVISTLQIlptvrEDSGFFSCHAIN 869
Cdd:cd05736    3 IRVYPEFQAKEPGVEASLRCHAEGIPLPRVQWLKNGMDINPKLSKQLTLIANGSELHISNVRY-----EDTGAYTCIAKN 77

                         90
                 ....*....|....*
gi 20127422  870 SYGEDRGIIQLTVQE 884
Cdd:cd05736   78 EGGVDEDISSLFVED 92

Immunoglobulin (Ig)-like domain of human titin C terminus and similar proteins; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the fifth immunoglobulin (Ig)-like domain from the C-terminus of human titin x and similar proteins. Titin (also called connectin) is a fibrous sarcomeric protein specifically found in vertebrate striated muscle. Titin is gigantic; depending on isoform composition it ranges from 2970 to 3700 kDa, and is of a length that spans half a sarcomere. Titin largely consists of multiple repeats of Ig-like and fibronectin type 3 (FN-III)-like domains. Titin connects the ends of myosin thick filaments to Z disks and extends along the thick filament to the H zone and appears to function similar to an elastic band, keeping the myosin filaments centered in the sarcomere during muscle contraction or stretching. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 143224 [Multi-domain] Cd Length: 92 Bit Score: 40.80 E-value: 5.20e-04

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 20127422  239 GQRVELPCKALGHPEPDYRWLKDNMPLELSGRFQKTVT----GLLIENIRPSDSGSYVCEVSNRYG 300
Cdd:cd05747   18 GESARFSCDVDGEPAPTVTWMREGQIIVSSQRHQITSTeyksTFEISKVQMSDEGNYTVVVENSEG 83

agrin-responsive first immunoglobulin-like domains (Ig1) of the MuSK ectodomain; a member of the I-set of IgSF domains; The members here are composed of the first immunoglobulin-like domains (Ig1) of the Muscle-specific kinase (MuSK). MuSK is a receptor tyrosine kinase specifically expressed in skeletal muscle, where it plays a central role in the formation and maintenance of the neuromuscular junction (NMJ). MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. The activation of MUSK in myotubes regulates the formation of NMJs through the regulation of different processes including the specific expression of genes in subsynaptic nuclei, the reorganization of the actin cytoskeleton and the clustering of the acetylcholine receptors (AChR) in the postsynaptic membrane. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the MuSK lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409562 [Multi-domain] Cd Length: 92 Bit Score: 40.95 E-value: 5.33e-04

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  327 VGSQVSLSCSVTGTEDQELSWYRNGEILNPG-KNVRITGINHEnLIMDHMVKSDGGAYQC 385
Cdd:cd20970   16 EGENATFMCRAEGSPEPEISWTRNGNLIIEFnTRYIVRENGTT-LTIRNIRRSDMGIYLC 74

Immunoglobulin domain of human Synaptic Adhesion-Like Molecule 5 (SALM5) and similar proteins; member of the I-set of IgSF domains; This group contains the immunoglobulin domain of human Synaptic Adhesion-Like Molecule 5 (SALM5) and similar proteins. The SALM (for synaptic adhesion-like molecules; also known as Lrfn for leucine-rich repeat and fibronectin type III domain containing) family of adhesion molecules consists of five known members: SALM1/Lrfn2, SALM2/Lrfn1, SALM3/Lrfn4, SALM4/Lrfn3, and SALM5/Lrfn5. SALMs share a similar domain structure, containing leucine-rich repeats (LRRs), an immunoglobulin (Ig) domain, and a fibronectin III (FNIII) domain, followed by a transmembrane domain and a C-terminal PDZ-binding motif. SALM5 is implicated in autism spectrum disorders (ASDs) and schizophrenia, induces presynaptic differentiation in contacting axons. SALM5 interacts with the Ig domains of LAR (Leukocyte common Antigen-Related) family receptor protein tyrosine phosphatases (LAR-RPTPs; LAR, PTPdelta, and PTPsigma). In addition, PTPdelta is implicated in ASDs, ADHD, bipolar disorder, and restless leg syndrome. Studies have shown that LAR-RPTPs are novel and splicing-dependent presynaptic ligands for SALM5, and that they mediate SALM5-dependent presynaptic differentiation. Furthermore, SALM5 maintains AMPA receptor (AMPAR)-mediated excitatory synaptic transmission through mechanisms involving the interaction of SALM5 with LAR-RPTPs. This group belongs to the I-set of immunoglobulin superfamily (IgSF) domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409421 [Multi-domain] Cd Length: 88 Bit Score: 40.92 E-value: 5.35e-04

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  684 LIVRVPPKFVVqprdqdgIYGKAVILNCSAEGYPVPTIVWKFSKGAGVPQfqpialNGRIQVLSNGSLLIKHVVEEDSGY 763
Cdd:cd05764    2 LITRHTHELRV-------LEGQRATLRCKARGDPEPAIHWISPEGKLISN------SSRTLVYDNGTLDILITTVKDTGA 68

                         90
                 ....*....|
gi 20127422  764 YLCKVSNDVG 773
Cdd:cd05764   69 FTCIASNPAG 78

Fourth immunoglobulin (Ig)-like domain of platelet-derived growth factor receptor (PDGFR); The members here are composed of the fourth immunoglobulin (Ig)-like domain of platelet-derived growth factor receptor (PDGFR; also known as cluster of differentiation (CD) 140a) alpha and beta. PDGF is a potent mitogen for connective tissue cells. PDGF-stimulated processes are mediated by three different PDGFs (PDGF-A,PDGF-B, and PDGF-C). PDGFR alpha binds to all three PDGFs, whereas the PDGFR beta binds only to PDGF-B. PDGF alpha is organized as an extracellular component having five Ig-like domains, a transmembrane segment, and a cytoplasmic portion having protein tyrosine kinase activity. In mice, PDGFR alpha and PDGFR beta are essential for normal development.

Pssm-ID: 409445 Cd Length: 101 Bit Score: 41.00 E-value: 5.40e-04

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 20127422  618 VVVSGDLPITITWQKDGRPIPGSLGVTIDNIDFTSSLR-ISNLSLMH-----NGNYTCIARNEAAAVEHQSQLIVRV 688
Cdd:cd05859   25 VEVEAYPPPQIRWLKDNRTLIENLTEITTSTRNVQETRyVSKLKLIRakeedSGLYTALAQNEDAVKSYTFALQIQV 101

Third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM); The members here are composed of the third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains, five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM.

Pssm-ID: 409460 [Multi-domain] Cd Length: 83 Bit Score: 40.66 E-value: 6.03e-04

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 20127422 1303 IVLPCKAVGDPSPAVKWMKDSNGTPSLVTIDGrrsiFSNGSFIIRTVKAEDSGYYSCIANNNWGS 1367
Cdd:cd05876   13 LVLECIAEGLPTPTVKWLRPSGPLPPDRVKYQ----NHNKTLQLLNVGESDDGEYVCLAENSLGS 73

First immunoglobulin (Ig)-like domain of Tyro3 receptor tyrosine kinase (RTK), and similar domains; The members here are composed of the first immunoglobulin (Ig)-like domain of Tyro3 receptor tyrosine kinase (RTK). Tyro3 together with Axl and Mer form the Axl/Tyro3 family of receptor tyrosine kinases (RTKs). This family includes Axl (also known as Ark, Ufo, and Tyro7), Tyro3 (also known as Sky, Rse, Brt, Dtk, and Tif), and Mer (also known as Nyk, c-Eyk, and Tyro12). Axl/Tyro3 family receptors have an extracellular portion with two Ig-like domains followed by two fibronectin-types III (FNIII) domains, a membrane-spanning single helix, and a cytoplasmic tyrosine kinase domain. Axl, Tyro3 and Mer are widely expressed in adult tissues, though they show higher expression in the brain, in the lymphatic and vascular systems, and in the testis. Axl, Tyro3, and Mer bind the vitamin K dependent protein Gas6 with high affinity, and in doing so activate their tyrosine kinase activity. Axl/Gas6 signaling may play a part in cell adhesion processes, prevention of apoptosis, and cell proliferation.

Pssm-ID: 409553 Cd Length: 87 Bit Score: 40.51 E-value: 6.90e-04

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  704 GKAVILNCSAEGYPVPTIVWkFSKGAGVPQ----FQPIALNGRIQVLSngsllIKHVVEEDSGYYLCKVSNDVGADVSKS 779
Cdd:cd20961    8 GQPVKLNCSVEGMEEPDIQW-VKDGAVVQNldqlYIPVSEQHWIGFLS-----LKSVERSDAGRYWCQVEDGGETEISQP 81


                 ....*.
gi 20127422  780 MYLTVK 785
Cdd:cd20961   82 VWLTVE 87

Second Ig domain of the neural cell adhesion molecule contactin-2, and similar domains; The members here are composed of the second Ig domain of the neural cell adhesion molecule contactin-2. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-2 (also called TAG-1, axonin-1) facilitates cell adhesion by homophilic binding between molecules in apposed membranes. The first four Ig domains form the intermolecular binding fragment which arranges as a compact U-shaped module by contacts between Ig domains 1 and 4, and domains 2 and 3. It has been proposed that a linear zipper-like array forms, from contactin-2 molecules alternatively provided by the two apposed membranes.

Pssm-ID: 409392 Cd Length: 88 Bit Score: 40.24 E-value: 7.28e-04

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 20127422  235 KAMAGQRVELPCKALGH-PEPDYRWLKDNMP--LELSGR-FQKTVTG-LLIENIRPSDSGSYVCEVSNRYGTAKVIGR 307
Cdd:cd05727    6 KVKEGWGVVLFCDPPPHyPDLSYRWLLNEFPnfIPEDGRrFVSQTNGnLYIAKVEASDRGNYSCFVSSPSSTKSVFSK 83

C-terminal immunoglobulin (Ig)-like domain of M-protein; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the C-terminal immunoglobulin (Ig)-like domain of M-protein (also known as myomesin-2). M-protein is a structural protein localized to the M-band, a transverse structure in the center of the sarcomere, and is a candidate for M-band bridges. M-protein is modular consisting mainly of repetitive IG-like and fibronectin type III (FnIII) domains and has a muscle-type specific expression pattern. M-protein is present in fast fibers.

Pssm-ID: 143299 Cd Length: 92 Bit Score: 40.66 E-value: 7.45e-04

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1301 KDIVLPCKAVGDPSPAVKWMK-DSNGTPS---LVTIDGRRSIfsngSFIIRTVKAEDSGYYSCIANNNWGSDEIILNLQV 1376
Cdd:cd05891   17 KTLNLTCTVFGNPDPEVIWFKnDQDIELSehySVKLEQGKYA----SLTIKGVTSEDSGKYSINVKNKYGGETVDVTVSV 92

Third immunoglobulin (Ig) domain of contactin-1; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-1. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-1 is differentially expressed in tumor tissues and may through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 143259 Cd Length: 88 Bit Score: 40.39 E-value: 7.46e-04

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  596 PPFIQ-PFEFPRFSIGQRVFIPCVVVSGDLPItITWQKDGRPIPGSLGVTIDNidftSSLRISNLSLMHNGNYTCIARNE 674
Cdd:cd05851    1 PADINvKFKDTYALKGQNVTLECFALGNPVPV-IRWRKILEPMPATAEISMSG----AVLKIFNIQPEDEGTYECEAENI 75

                         90
                 ....*....|...
gi 20127422  675 AAAVEHQSQLIVR 687
Cdd:cd05851   76 KGKDKHQARVYVQ 88

Fourth Ig domain of the neural cell adhesion molecule contactin-2, and similar domains; The members here are composed of the fourth Ig domain of the neural cell adhesion molecule contactin-2. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-2 (also called TAG-1, axonin-1) facilitates cell adhesion by homophilic binding between molecules in apposed membranes. The first four Ig domains form the intermolecular binding fragment which arranges as a compact U-shaped module by contacts between Ig domains 1 and 4, and domains 2 and 3. It has been proposed that a linear zipper-like array forms, from contactin-2 molecules alternatively provided by the two apposed membranes.

Pssm-ID: 143205 [Multi-domain] Cd Length: 85 Bit Score: 40.28 E-value: 8.52e-04

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 20127422  320 PRKVKSSVGSQVSLSCSVTGTEDQELSWYRNGEILNPGKNVRITGinhENLIMDHMVKSDGGAYQC 385
Cdd:cd05728    6 ISDTEADIGSSLRWECKASGNPRPAYRWLKNGQPLASENRIEVEA---GDLRITKLSLSDSGMYQC 68

Immunoglobulin (Ig)-like domain in neuregulins; The members here are composed of the immunoglobulin (Ig)-like domain in neuregulins (NRGs). NRGs are signaling molecules which participate in cell-cell interactions in the nervous system, breast, heart, and other organ systems, and are implicated in the pathology of diseases including schizophrenia, multiple sclerosis, and breast cancer. There are four members of the neuregulin gene family (NRG-1, NRG-2, NRG-3, and NRG-4). The NRG-1 protein, binds to and activates the tyrosine kinases receptors ErbB3 and ErbB4, initiating signaling cascades. The other NRGs proteins bind one or the other or both of these ErbBs. NRG-1 has multiple functions: in the brain it regulates various processes such as radial glia formation and neuronal migration, dendritic development, and expression of neurotransmitters receptors, while in the peripheral nervous system NRG-1 regulates processes such as target cell differentiation, and Schwann cell survival. There are many NRG-1 isoforms which arise from the alternative splicing of mRNA. Less is known of the functions of the other NRGs. NRG-2 and NRG-3 are expressed predominantly in the nervous system. NRG-2 is expressed by motor neurons and terminal Schwann cells, and is concentrated near synaptic sites and may be a signal that regulates synaptic differentiation. NRG-4 has been shown to direct pancreatic islet cell development towards the delta-cell lineage.

Pssm-ID: 409408 [Multi-domain] Cd Length: 92 Bit Score: 40.19 E-value: 8.58e-04

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 20127422  597 PFIQPFEFPRFSIGQRVFIPCVVVSGDLPITITWQKDGRPI--PGSLGVTIDNIDFTSSLRISNLSLMHNGNYTCIARN 673
Cdd:cd05750    1 PKLKEMKSQTVQEGSKLVLKCEATSENPSPRYRWFKDGKELnrKRPKNIKIRNKKKNSELQINKAKLEDSGEYTCVVEN 79

Second immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. DSCAM is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409545 Cd Length: 95 Bit Score: 40.22 E-value: 8.94e-04

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  224 APSI--LDGFDHRKAMAGQRVELPCKALGHPEPDYRWLK------DNMPLELSGRFqKTVTG-LLIENIRPSDSGSYVCE 294
Cdd:cd20953    1 APKIpgLSKSQPLTVSSASSIALLCPAQGYPAPSFRWYKfiegttRKQAVVLNDRV-KQVSGtLIIKDAVVEDSGKYLCV 79

                         90
                 ....*....|
gi 20127422  295 VSNRYGTAKV 304
Cdd:cd20953   80 VNNSVGGESV 89

Immunoglobulin (Ig)-like domain of human carcinoembryonic antigen (CEA) related cell adhesion molecule (CEACAM) domains 2, 4, and 6, and similar domains; The members here are composed of the second, fourth, and sixth immunoglobulin (Ig)-like domains in human carcinoembryonic antigen (CEA) related cell adhesion molecule (CEACAM) protein subfamily. The CEA family is a group of anchored or secreted glycoproteins expressed by epithelial cells, leukocytes, endothelial cells, and placenta. The CEA family is divided into the CEACAM and pregnancy-specific glycoprotein (PSG) subfamilies. This group represents the CEACAM subfamily. CEACAM1 has many important cellular functions; it is a cell adhesion molecule and a signaling molecule that regulates the growth of tumor cells, an angiogenic factor, and a receptor for bacterial and viral pathogens, including mouse hepatitis virus (MHV). In mice, four isoforms of CEACAM1 generated by alternative splicing have either two [D1, D4] or four [D1-D4] Ig-like domains on the cell surface.

Pssm-ID: 409402 [Multi-domain] Cd Length: 89 Bit Score: 40.07 E-value: 9.09e-04

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  240 QRVELPCKALGHPEpDYRWLKDNMPLELSGRFQKTVTG--LLIENIRPSDSGSYVCEVSN 297
Cdd:cd05740   16 DAVTLTCEPETQNT-SYLWWFNGQSLPVTPRLTLSNGNrtLTLLNVTREDAGAYQCEISN 74

Immunoglobulin I-set domain of the Leucine-rich repeat and immunoglobin-like domain-containing protein 1 (Lingo-1); The members here are composed of the immunoglobulin I-set (IgI) domain of the Leucine-rich repeat and immunoglobin-like domain-containing protein 1 (Lingo-1). Human Lingo-1 is a central nervous system-specific transmembrane glycoprotein also known as LERN-1, which functions as a negative regulator of neuronal survival, axonal regeneration, and oligodendrocyte differentiation and myelination. Lingo-1 is a key component of the Nogo receptor signaling complex (RTN4R/NGFR) in RhoA activation responsible for some inhibition of axonal regeneration by myelin-associated factors. The ligand-binding ectodomain of human Lingo-1 contains a bimodular, kinked structure composed of leucine-rich repeat (LRR) and immunoglobulin (Ig)-like modules. Diseases associated with Lingo-1 include mental retardation, autosomal recessive 64 and essential tremor. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the Lingo-1 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409561 Cd Length: 92 Bit Score: 40.45 E-value: 9.30e-04

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 20127422  238 AGQRVELPCKALGHPEPDYRWL---KDNMPLELSGRFQKTVTGLL-IENIRPSDSGSYVCEVSNRYGTAKVIGRLYV 310
Cdd:cd20969   16 EGHTVQFVCRADGDPPPAILWLsprKHLVSAKSNGRLTVFPDGTLeVRYAQVQDNGTYLCIAANAGGNDSMPAHLHV 92

Fifth Ig-like domain of Roundabout (Robo) homolog 1/2, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the fifth Ig-like domain of Roundabout (Robo) homolog 1/2 and similar domains. Robo receptors play a role in the development of the central nervous system (CNS), and are receptors of Slit protein. Slit is a repellant secreted by the neural cells in the midline. Slit acts through Robo to prevent most neurons from crossing the midline from either side. Three mammalian Robo homologs (Robo1, -2, and -3), and three mammalian Slit homologs (Slit-1,-2, -3), have been identified. Commissural axons, which cross the midline, express low levels of Robo; longitudinal axons, which avoid the midline, express high levels of Robo. Robo1, -2, and -3 are expressed by commissural neurons in the vertebrate spinal cord and Slits 1, -2, -3 are expressed at the ventral midline. Robo-3 is a divergent member of the Robo family which instead of being a positive regulator of slit responsiveness, antagonizes slit responsiveness in precrossing axons. The Slit-Robo interaction is mediated by the second leucine-rich repeat (LRR) domain of Slit and the two N-terminal Ig domains of Robo, Ig1 and Ig2. The primary Robo binding site for Slit2 has been shown by surface plasmon resonance experiments and mutational analysis to be is the Ig1 domain, while the Ig2 domain has been proposed to harbor a weak secondary binding site. The fifth Ig-like domain of Robo 1 and 2 is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors

Pssm-ID: 409544 [Multi-domain] Cd Length: 87 Bit Score: 40.17 E-value: 9.71e-04

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  317 TISPRKVKSSVGSQVSLSCSVTGTEDQELSWYRNGEILnPGKNVRITGINHENLIMDHMVKSDGGAYQCFVRkdKLSAQD 396
Cdd:cd20952    3 LQGPQNQTVAVGGTVVLNCQATGEPVPTISWLKDGVPL-LGKDERITTLENGSLQIKGAEKSDTGEYTCVAL--NLSGEA 79


                 ....*..
gi 20127422  397 YVQVVLE 403
Cdd:cd20952   80 TWSAVLD 86

Fourth Ig-like domain from smooth muscle myosin light chain kinase and similar domains ; a member of the I-set of IgSF domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain from smooth muscle myosin light chain kinase (MYLK) and similar domains. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of this group shows that the fourth Ig-like domain from myosin light chain kinase lacks this strand and thus belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409568 [Multi-domain] Cd Length: 90 Bit Score: 39.93 E-value: 1.01e-03

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  504 PASIRPMKNITAIAGRDTYIHCRVIGYPYYSIKWYKNSNLLPFNHRQVAFE-NNGTLKLSDVQKEvDEGEYTCnvLVQPQ 582
Cdd:cd20976    2 PSFSSVPKDLEAVEGQDFVAQCSARGKPVPRITWIRNAQPLQYAADRSTCEaGVGELHIQDVLPE-DHGTYTC--LAKNA 78

                         90
                 ....*....|..
gi 20127422  583 LST-SQSVHVTV 593
Cdd:cd20976   79 AGQvSCSAWVTV 90

Immunoglobulin domain; Members of the immunoglobulin superfamily are found in hundreds of proteins of different functions. Examples include antibodies, the giant muscle kinase titin and receptor tyrosine kinases. Immunoglobulin-like domains may be involved in protein-protein and protein-ligand interactions.

Pssm-ID: 395002 Cd Length: 86 Bit Score: 39.87 E-value: 1.02e-03

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 20127422    417 VVSPAEPVSLMCNVK-GTPLPTITWTLDDDPILkgGSHRISQMITSEGNvvSYLNISSSQVRDGGVYRCTANNSAGVV 493
Cdd:pfam00047    7 TVLEGDSATLTCSAStGSPGPDVTWSKEGGTLI--ESLKVKHDNGRTTQ--SSLLISNVTKEDAGTYTCVVNNPGGSA 80

Immunoglobulin (Ig)-like domain found in Perlecan and similar proteins; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig)-like domain found in Perlecan. Perlecan is a large multi-domain heparin sulfate proteoglycan, important in tissue development and organogenesis. Perlecan can be represented as 5 major portions; its fourth major portion (domain IV) is a tandem repeat of immunoglobulin-like domains (Ig2-Ig15) which can vary in size due to alternative splicing. Perlecan binds many cellular and extracellular ligands. Its domain IV region has many binding sites. Some of these have been mapped at the level of individual Ig-like domains, including a site restricted to the Ig5 domain for heparin/sulfatide, a site restricted to the Ig3 domain for nidogen-1 and nidogen-2, a site restricted to Ig4-5 for fibronectin, and sites restricted to Ig2 and to Ig13-15 for fibulin-2. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409412 Cd Length: 85 Bit Score: 39.85 E-value: 1.05e-03

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 20127422 1294 TVTTPWMKDIVLPCKAVG-DPSPAVKWMKdSNGT-PSlvtidgrRSIFSNGSFIIRTVKAEDSGYYSCIANNNWGSDE 1369
Cdd:cd05754   10 SQEVRPGADVSFICRAKSkSPAYTLVWTR-VNGTlPS-------RAMDFNGILTIRNVQLSDAGTYVCTGSNMLDTDE 79

Immunoglobulin domain I1 of the titin I-band and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin domain I1 of the titin I-band and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. The two sheets are linked together by a conserved disulfide bond between B strand and F strand. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The Ig I1 domain of the titin I-band is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409543 [Multi-domain] Cd Length: 94 Bit Score: 40.10 E-value: 1.07e-03

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  238 AGQRVELPCKALGHPEPDYRWLKDNMPLELSGRFQK-------TVTGLLIENIRPSDSGSYVCEVSNRYGTAKVIGRLYV 310
Cdd:cd20951   14 EKSDAKLRVEVQGKPDPEVKWYKNGVPIDPSSIPGKykieseyGVHVLHIRRVTVEDSAVYSAVAKNIHGEASSSASVVV 93


                 .
gi 20127422  311 K 311
Cdd:cd20951   94 E 94

Immunoglobulin (Ig)-like domain of human carcinoembryonic antigen (CEA) related cell adhesion molecule (CEACAM) domains 2, 4, and 6, and similar domains; The members here are composed of the second, fourth, and sixth immunoglobulin (Ig)-like domains in human carcinoembryonic antigen (CEA) related cell adhesion molecule (CEACAM) protein subfamily. The CEA family is a group of anchored or secreted glycoproteins expressed by epithelial cells, leukocytes, endothelial cells, and placenta. The CEA family is divided into the CEACAM and pregnancy-specific glycoprotein (PSG) subfamilies. This group represents the CEACAM subfamily. CEACAM1 has many important cellular functions; it is a cell adhesion molecule and a signaling molecule that regulates the growth of tumor cells, an angiogenic factor, and a receptor for bacterial and viral pathogens, including mouse hepatitis virus (MHV). In mice, four isoforms of CEACAM1 generated by alternative splicing have either two [D1, D4] or four [D1-D4] Ig-like domains on the cell surface.

Pssm-ID: 409402 [Multi-domain] Cd Length: 89 Bit Score: 40.07 E-value: 1.09e-03

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  706 AVILNCSAEGyPVPTIVWKFSKgagvpqfQPIALNGRIQvLSNG--SLLIKHVVEEDSGYYLCKVSNDVGADVSKSMYLT 783
Cdd:cd05740   17 AVTLTCEPET-QNTSYLWWFNG-------QSLPVTPRLT-LSNGnrTLTLLNVTREDAGAYQCEISNPVSANRSDPVTLD 87


                 .
gi 20127422  784 V 784
Cdd:cd05740   88 V 88

Immunoglobulin-like domain of human Aortic Preferentially Expressed Protein-1 (APEG-1) and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin I-set (IgI) domain of the Human Aortic Preferentially Expressed Protein-1 (APEG-1) and similar proteins. APEG-1 is a novel specific smooth muscle differentiation marker predicted to play a role in the growth and differentiation of arterial smooth muscle cells (SMCs). The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the human APEG-1 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409567 Cd Length: 91 Bit Score: 40.15 E-value: 1.16e-03

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1301 KDIVLPCKAVGDPSPAVKWMKdsNGTPslVTIDGRR--SIFSNGSFIIRTVKAE--DSGYYSCIANNNWGSDEIILNLQV 1376
Cdd:cd20975   16 QDVIMSIRVQGEPKPVVSWLR--NRQP--VRPDQRRfaEEAEGGLCRLRILAAErgDAGFYTCKAVNEYGARQCEARLEV 91

Ig-like domain on T-cell surface glycoprotein CD3 epsilon chain; Ig_5 is an immunoglobulin domain found on T-cell surface glycoprotein CD3 epsilon chain. It forms a first-order complex with T-cell surface glycoprotein CD3 delta chain as part of the T-cell receptor complex.

Pssm-ID: 465232 Cd Length: 75 Bit Score: 39.23 E-value: 1.16e-03

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 20127422    239 GQRVELPCKalGHPEPDYRWLKDNMPLELSGRFQktvtgLLIENI-RPSDSGSYVCEVSNRYGTAkvigRLYVK 311
Cdd:pfam16681    7 GTTVTLTCP--LDSEEKIKWEKNDKPLEDSNDLE-----LKLENFsEMEDSGYYSCYSSNSNKTH----YLYLK 69

Fourth immunoglobulin (Ig)-like domain of L1, Ng-CAM (Neuron-glia CAM cell adhesion molecule), and NrCAM (Ng-CAM-related); The members here are composed of the fourth immunoglobulin (Ig)-like domain of L1, Ng-CAM (Neuron-glia CAM cell adhesion molecule), and NrCAM (Ng-CAM-related). These proteins belong to the L1 subfamily of cell adhesion molecules (CAMs) and are comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. These molecules are primarily expressed in the nervous system. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth.

Pssm-ID: 409367 [Multi-domain] Cd Length: 89 Bit Score: 39.74 E-value: 1.17e-03

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  686 VRVPPKFVVQPrdqdgiyGKAVILNCSAEGYPVPTIVWKFSkgaGVP-QFQPIA----LNGRIQVLSNgsllikhVVEED 760
Cdd:cd04978    3 IIEPPSLVLSP-------GETGELICEAEGNPQPTITWRLN---GVPiEPAPEDmrrtVDGRTLIFSN-------LQPND 65

                         90
                 ....*....|...
gi 20127422  761 SGYYLCKVSNDVG 773
Cdd:cd04978   66 TAVYQCNASNVHG 78

Fifth immunoglobulin (Ig) domain of contactin-1; The members here are composed of the fifth immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-1. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-1 is differentially expressed in tumor tissues and may through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409438 Cd Length: 89 Bit Score: 39.98 E-value: 1.21e-03

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  690 PKFVVQPRDQDGIYGKA--VILNCSAEGYPVPTIVWkfSKGAgvpqfQPIALNGRIQVLSNGSLLIKHVVEEDSGYYLCK 767
Cdd:cd05852    1 PTFEFNPMKKKILAAKGgrVIIECKPKAAPKPKFSW--SKGT-----ELLVNNSRISIWDDGSLEILNITKLDEGSYTCF 73


                 ....*.
gi 20127422  768 VSNDVG 773
Cdd:cd05852   74 AENNRG 79

Immunoglobulin (Ig)-like domain of the human basement membrane heparan sulfate proteoglycan perlecan and similar proteins; The members here are composed of the immunoglobulin (Ig)-like domain of the human basement membrane heparan sulfate proteoglycan perlecan, also known as HSPG2, and similar proteins. Perlecan consists of five domains: domain I has three putative heparan sulfate attachment sites, domain II has four LDL receptor-like repeats, and one Ig-like repeat, domain III resembles the short arm of laminin chains, domain IV has multiple Ig-like repeats (21 repeats in human perlecan), and domain V resembles the globular G domain of the laminin A chain and internal repeats of EGF. Perlecan may participate in a variety of biological functions including cell binding, LDL-metabolism, basement membrane assembly and selective permeability, calcium binding, and growth- and neurite-promoting activities.

Pssm-ID: 143220 Cd Length: 78 Bit Score: 39.40 E-value: 1.26e-03

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 20127422 1305 LPCKAVGDPSPAVKWMKDSNGTPS----LVTIDGRRsifsnGSFIIRTVKAEDSGYYSCIANNNWG 1366
Cdd:cd05743    6 FTCVATGVPTPIINWRLNWGHVPDsarvSITSEGGY-----GTLTIRDVKESDQGAYTCEAINTRG 66

Immunoglobulin-like Ig0 domain of basigin-1 (BSG1) and similar proteins; The members here are composed of the immunoglobulin (Ig) domain of the collagenase stimulatory factor, basigin-1 (BSG1; also known as Cluster of Differentiation 147 (CD147) and Extracellular Matrix Metalloproteinase Inducer (EMMPRIN)) and similar proteins. CD147 is a transmembrane glycoprotein that belongs to the immunoglobulin superfamily. It is expressed in nearly all cells including platelets and fibroblasts and is involved in inflammatory diseases, and cancer progression. CD147 is highly expressed in several cancers and used as a prognostic marker. The two primary isoforms of CD147 that are related to cancer progression have been identified: CD147 Ig1-Ig2 (also called Basigin-2) that is ubiquitously expressed in most tissues and CD147 Ig0-Ig1-Ig2 (also called Basigin-1) that is retinal specific and implicated in retinoblastoma. Studies showed that CD147 Ig0 domain is a potent stimulator of interleukin-6 and suggest that the CD147 Ig0 dimer is the functional unit required for activity.

Pssm-ID: 409534 Cd Length: 116 Bit Score: 40.72 E-value: 1.28e-03

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1292 SGTVTTP-----WMKDIV-LPCKAVGDPSPAVKWMKDSNGTPSLVT--IDGRR----------SIFSNGSFIIRTVKAED 1353
Cdd:cd20940    1 AGFIKSPlsqqrLVGDSVeLHCEAVGSPIPEIQWWFEGQEPNEICSqlWDGARldrvhinatyHQHATSTISIDNLTEED 80

                         90
                 ....*....|.
gi 20127422 1354 SGYYSCIANNN 1364
Cdd:cd20940   81 TGTYECRASND 91

First immunoglobulin (Ig)-like domain of neural cell adhesion molecule NCAM-1, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain of neural cell adhesion molecule NCAM-1. NCAM-1 plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM) and heterophilic (NCAM-nonNCAM) interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves the Ig1, Ig2, and Ig3 domains. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions), through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain. Also included in this group is NCAM-2 (also known as OCAM/mamFas II and RNCAM). NCAM-2 is differentially expressed in the developing and mature olfactory epithelium (OE). This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409366 Cd Length: 95 Bit Score: 39.93 E-value: 1.34e-03

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  314 LKATISPRKVKSSVGSQVSLSCSVTGtEDQELSWYR-NGEILNPgKNVRITGINHEN----LIMDHMVKSDGGAYQCfVR 388
Cdd:cd04977    1 LQVKIIPSYAEISVGESKFFLCKVSG-DAKNINWVSpNGEKVLT-KHGNLKVVNHGSvlssLTIYNANINDAGIYKC-VA 77

                         90
                 ....*....|....*
gi 20127422  389 KDKLSAQDYVQVVLE 403
Cdd:cd04977   78 TNGKGTESEATVKLD 92

Immunoglobulin (Ig)-like domain of the human basement membrane heparan sulfate proteoglycan perlecan and similar proteins; The members here are composed of the immunoglobulin (Ig)-like domain of the human basement membrane heparan sulfate proteoglycan perlecan, also known as HSPG2, and similar proteins. Perlecan consists of five domains: domain I has three putative heparan sulfate attachment sites, domain II has four LDL receptor-like repeats, and one Ig-like repeat, domain III resembles the short arm of laminin chains, domain IV has multiple Ig-like repeats (21 repeats in human perlecan), and domain V resembles the globular G domain of the laminin A chain and internal repeats of EGF. Perlecan may participate in a variety of biological functions including cell binding, LDL-metabolism, basement membrane assembly and selective permeability, calcium binding, and growth- and neurite-promoting activities.

Pssm-ID: 143220 Cd Length: 78 Bit Score: 39.40 E-value: 1.34e-03

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 20127422  610 GQRVFIPCVVVSGDLPItITWQKDGRPIPGSLGVTIDNIDFTSSLRISNLSLMHNGNYTCIARNEAAAVEHQSQLIVRV 688
Cdd:cd05743    1 GETVEFTCVATGVPTPI-INWRLNWGHVPDSARVSITSEGGYGTLTIRDVKESDQGAYTCEAINTRGMVFGIPDGILTV 78

immunoglobulin-like domain of telokin and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin (Ig) domain in telokin, the C-terminal domain of myosin light chain kinase which is identical to telokin, and similar proteins. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the telokin Ig domain lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409565 [Multi-domain] Cd Length: 88 Bit Score: 39.48 E-value: 1.37e-03

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 20127422  507 IRPMKNITAIAGRDTYIHCRVIGYPYYSIKWYKNSN-LLPFNHRQVAFENNG--TLKLSDVQKEvDEGEYTC 575
Cdd:cd20973    1 IQTLRDKEVVEGSAARFDCKVEGYPDPEVKWMKDDNpIVESRRFQIDQDEDGlcSLIISDVCGD-DSGKYTC 71

Seventh immunoglobulin domain of the Drosophila melanogaster Dscam protein, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the seventh immunoglobulin domain of the Drosophila melanogaster Down syndrome cell adhesion molecule (DSCAM) protein and similar proteins. Down syndrome cell adhesion molecule (DSCAM) is a cell adhesion molecule that plays critical roles in neural development, including axon guidance and branching, axon target recognition, self-avoidance and synaptic formation. DSCAM belongs to the immunoglobulin superfamily and contributes to defects in the central nervous system in Down syndrome patients. Vertebrate DSCAMs differ from Drosophila Dscam1 in that they lack the extensive alternative splicing that occurs in the insect gene. Drosophila melanogaster Dscam has 38,016 isoforms generated by the alternative splicing of four variable exon clusters, which allows every neuron in the fly to display a distinctive set of Dscam proteins on its cell surface. Drosophila Dscam1 is a cell-surface protein that plays important roles in neural development and axon tiling of neurons. It is shown that thousands of isoforms bind themselves through specific homophilic (self-binding) interactions, a process which mediates cellular self-recognition. Drosophila Dscam2 is also alternatively spliced and plays a key role in the development of two visual system neurons, monopolar cells L1 and L2. This group is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand.

Pssm-ID: 409546 [Multi-domain] Cd Length: 96 Bit Score: 39.99 E-value: 1.38e-03

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  238 AGQRVELPCKALGHPEPDYRWLK---------------DNMPLELSGrfqktvtGLLIENIRPSDSGSYVCEVSNRYGT- 301
Cdd:cd20954   15 AGQDVMLHCQADGFPTPTVTWKKatgstpgeykdllydPNVRILPNG-------TLVFGHVQKENEGHYLCEAKNGIGSg 87


                 ....*
gi 20127422  302 -AKVI 305
Cdd:cd20954   88 lSKVI 92

Second C-terminal immunoglobulin (Ig)-like domain of palladin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the C-terminal immunoglobulin (Ig)-like domain of palladin. Palladin belongs to the palladin-myotilin-myopalladin family. Proteins belonging to this family contain multiple Ig-like domains and function as scaffolds, modulating actin cytoskeleton. Palladin binds to alpha-actinin ezrin, vasodilator-stimulated phosphoprotein VASP, SPIN90 (also known as DIP or mDia interacting protein), and Src. Palladin also binds F-actin directly, via its Ig3 domain. Palladin is expressed as several alternatively spliced isoforms, having various combinations of Ig-like domains, in a cell-type-specific manner. It has been suggested that palladin's different Ig-like domains may be specialized for distinct functions. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409582 Cd Length: 91 Bit Score: 39.70 E-value: 1.41e-03

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 20127422  239 GQRVELPCKALGHPEPDYRWLKDNMPLELSGRF-----QKTVTGLLIENIRPSDSGSYVCEVSNRYG 300
Cdd:cd20990   15 GKLCRMDCKVSGLPTPDLSWQLDGKPIRPDSAHkmlvrENGVHSLIIEPVTSRDAGIYTCIATNRAG 81

Immunoglobulin domain; This domain contains immunoglobulin-like domains.

Pssm-ID: 464026 [Multi-domain] Cd Length: 79 Bit Score: 39.30 E-value: 1.51e-03

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422    794 PNTTLATQGQKKEMSCTAHGEKPIIVRWEKEDRIINPEMaRYLVSTKEVgeevistlqilptvrEDSGFFSCHAINS-YG 872
Cdd:pfam13895    6 PSPTVVTEGEPVTLTCSAPGNPPPSYTWYKDGSAISSSP-NFFTLSVSA---------------EDSGTYTCVARNGrGG 69

                           90
                   ....*....|
gi 20127422    873 EDRGIIQLTV 882
Cdd:pfam13895   70 KVSNPVELTV 79

Immunoglobulin domain I1 of the titin I-band and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin domain I1 of the titin I-band and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. The two sheets are linked together by a conserved disulfide bond between B strand and F strand. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The Ig I1 domain of the titin I-band is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409543 [Multi-domain] Cd Length: 94 Bit Score: 39.71 E-value: 1.55e-03

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  504 PASIRPMKNITAIAGRDTYIHCRVIGYPYYSIKWYKNSNLL-----PFNHRQVAFENNGTLKLSDVQKEvDEGEYTCNVL 578
Cdd:cd20951    1 PEFIIRLQSHTVWEKSDAKLRVEVQGKPDPEVKWYKNGVPIdpssiPGKYKIESEYGVHVLHIRRVTVE-DSAVYSAVAK 79

                         90
                 ....*....|....
gi 20127422  579 -VQPQLSTSQSVHV 591
Cdd:cd20951   80 nIHGEASSSASVVV 93

agrin-responsive second immunoglobulin-like domains (Ig2) of the Muscle-specific kinase (MuSK) ectodomain; a member of the I-set of Ig superfamily domains; The members here are composed of the second immunoglobulin-like (Ig) domains of the Muscle-specific kinase (MuSK) ectodomain. MuSK is a receptor tyrosine kinase specifically expressed in skeletal muscle, where it plays a central role in the formation and maintenance of the neuromuscular junction (NMJ). MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. The activation of MUSK in myotubes regulates the formation of NMJs through the regulation of different processes including the specific expression of genes in subsynaptic nuclei, the reorganization of the actin cytoskeleton and the clustering of the acetylcholine receptors (AChR) in the postsynaptic membrane. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the MuSK lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409560 [Multi-domain] Cd Length: 88 Bit Score: 39.53 E-value: 1.57e-03

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 20127422  426 LMCNVKGTPLPTITWTLDDDpILKGGShRISqmITSEGNvvsyLNISSSQVRDGGVYRCTANNSAGV 492
Cdd:cd20968   19 LPCTTMGNPKPSVSWIKGDD-LIKENN-RIA--VLESGS----LRIHNVQKEDAGQYRCVAKNSLGI 77

Immunoglobulin domain; This domain contains immunoglobulin-like domains.

Pssm-ID: 464026 [Multi-domain] Cd Length: 79 Bit Score: 39.30 E-value: 1.58e-03

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422    407 PKIISAFSekVVSPAEPVSLMCNVKGTPLPTITWTLDDDPILKGGShrisqmitsegnvVSYLNISSSqvrDGGVYRCTA 486
Cdd:pfam13895    2 PVLTPSPT--VVTEGEPVTLTCSAPGNPPPSYTWYKDGSAISSSPN-------------FFTLSVSAE---DSGTYTCVA 63


                   ....*.
gi 20127422    487 NNSAGV 492
Cdd:pfam13895   64 RNGRGG 69

Second immunoglobulin (Ig)-like domain of hemolin, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of hemolin and similar proteins. Hemolin, an insect immunoglobulin superfamily (IgSF) member containing four Ig-like domains, is a lipopolysaccharide-binding immune protein induced during bacterial infection. Hemolin shares significant sequence similarity with the first four Ig-like domains of the transmembrane cell adhesion molecules (CAMs) of the L1 family. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structures of this group show that the second Ig domain lacks this strand and thus belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules, including vascular (VCAM), intercellular (ICAM), neural (NCAM) and mucosal addressin (MADCAM) cell adhesion molecules, as well as junction adhesion molecules (JAM).

Pssm-ID: 409557 Cd Length: 101 Bit Score: 39.92 E-value: 1.63e-03

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 20127422  702 IYGKAVILNCS-AEGYPVPTIVWKFSKGAGVPQFQPIaLNGRIQVLSNGSLLIKHVVEED---SGYYLCKVSN 770
Cdd:cd20965   15 VEGKPFKLDCNvPPGYPKPTIEWKKQLVSDSSKADTI-LDRRITISPNGDLYFTNVTKEDvstDYKYVCVAKT 86

Third immunoglobulin-like domain of the human WFIKKN (WAP, follistatin, immunoglobulin, Kunitz and NTR domain-containing protein), and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin-like domain of the human WFIKKN (WAP, follistatin, immunoglobulin, Kunitz and NTR domain-containing protein) and similar proteins. WFIKKN is a secreted protein that consists of multiple types of protease inhibitory modules, including two tandem Kunitz-type protease inhibitor-domains. The Ig superfamily is a heterogenous group of proteins built on a common fold comprised of a sandwich of two beta sheets. Members of the Ig superfamily are components of immunoglobulin, neuroglia, cell surface glycoproteins, such as T-cell receptors, CD2, CD4, CD8, and membrane glycoproteins, such as butyrophilin and chondroitin sulfate proteoglycan core protein. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409422 [Multi-domain] Cd Length: 95 Bit Score: 39.45 E-value: 1.69e-03

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  690 PKFVVQPRDQDGIYGKAVILNCSAEGYPVPTIVW-KFSKGAGVPQFQPIALNGRIQVLSNGSLLIKHVVEEDSGYYLCKV 768
Cdd:cd05765    1 PALVNSPTHQTVKVGETASFHCDVTGRPQPEITWeKQVPGKENLIMRPNHVRGNVVVTNIGQLVIYNAQPQDAGLYTCTA 80


                 ....*
gi 20127422  769 SNDVG 773
Cdd:cd05765   81 RNSGG 85

Immunoglobulin (Ig)-like domain in neuregulins; The members here are composed of the immunoglobulin (Ig)-like domain in neuregulins (NRGs). NRGs are signaling molecules which participate in cell-cell interactions in the nervous system, breast, heart, and other organ systems, and are implicated in the pathology of diseases including schizophrenia, multiple sclerosis, and breast cancer. There are four members of the neuregulin gene family (NRG-1, NRG-2, NRG-3, and NRG-4). The NRG-1 protein, binds to and activates the tyrosine kinases receptors ErbB3 and ErbB4, initiating signaling cascades. The other NRGs proteins bind one or the other or both of these ErbBs. NRG-1 has multiple functions: in the brain it regulates various processes such as radial glia formation and neuronal migration, dendritic development, and expression of neurotransmitters receptors, while in the peripheral nervous system NRG-1 regulates processes such as target cell differentiation, and Schwann cell survival. There are many NRG-1 isoforms which arise from the alternative splicing of mRNA. Less is known of the functions of the other NRGs. NRG-2 and NRG-3 are expressed predominantly in the nervous system. NRG-2 is expressed by motor neurons and terminal Schwann cells, and is concentrated near synaptic sites and may be a signal that regulates synaptic differentiation. NRG-4 has been shown to direct pancreatic islet cell development towards the delta-cell lineage.

Pssm-ID: 409408 [Multi-domain] Cd Length: 92 Bit Score: 39.42 E-value: 1.73e-03

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  506 SIRPMKNITAIAGRDTYIHCRVIG-YPYYSIKWYKNSNLL----PFNHRQVAFENNGTLKLSDVQKEvDEGEYTCnvLVQ 580
Cdd:cd05750    2 KLKEMKSQTVQEGSKLVLKCEATSeNPSPRYRWFKDGKELnrkrPKNIKIRNKKKNSELQINKAKLE-DSGEYTC--VVE 78

                         90
                 ....*....|....
gi 20127422  581 PQL---STSQSVHV 591
Cdd:cd05750   79 NILgkdTVTGNVTV 92

Immunoglobulin domain; This domain contains immunoglobulin-like domains.

Pssm-ID: 464026 [Multi-domain] Cd Length: 79 Bit Score: 38.92 E-value: 1.93e-03

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 20127422   1301 KDIVLPCKAVGDPSPAVKWMKDSNGTPSlvtidgrrsifsNGSFIIRTVKAEDSGYYSCIANNNWGS 1367
Cdd:pfam13895   15 EPVTLTCSAPGNPPPSYTWYKDGSAISS------------SPNFFTLSVSAEDSGTYTCVARNGRGG 69

N-terminal immunoglobulin (Ig)-like domain of T-cell surface antigen CD2, and similar domains; The members here are composed of the N-terminal immunoglobulin (Ig)-like domain (or domain 1) of T-cell surface antigen Clusters of Differentiation (CD) 2 and similar proteins. CD2 is a T-cell specific surface glycoprotein and is critically important for mediating adhesion between T cells and antigen-presenting cells or between cytolytic T cells and target cells. CD2 is located on chromosome 1 at 1p13 in humans and on chromosome 3 in mice. CD2 contains an extracellular domain with two or Ig-like domains, a single transmembrane segment, and a cytoplasmic region rich in proline and basic residues.

Pssm-ID: 409431 Cd Length: 98 Bit Score: 39.64 E-value: 1.93e-03

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  701 GIYGKAVILNCSAEGYPVPTIVWKFSK--------GAGVPQFQPiaLNGRIQVL-SNGSLLIKHVVEEDSGYYLCKVSND 771
Cdd:cd05775    7 GALGGNVTLTISSLQDDIDEIKWKKTKdkivewenNIGPTYFGS--FKDRVLLDkESGSLTIKNLTKEDSGTYELEITST 84

                         90
                 ....*....|....
gi 20127422  772 VGADVSKSMYLTVK 785
Cdd:cd05775   85 NGKVLSSKFTLEVL 98

Immunoglobulin Variable (IgV) domain in HERV-H LTR-associating 2 (HHLA2); The members here are composed of the immunoglobulin variable (IgV) region in HERV-H LTR-associating 2 (HHLA2; also known as B7-H7/B7 homolog 7). HHLA2 is a member of the B7 family of immune regulatory proteins. Mature human HHLA2 consists of an extracellular domain (ECD) with three immunoglobulin-like domains, a transmembrane segment, and a cytoplasmic domain. HHLA2 is widely expressed in human cancers including non-small cell lung carcinoma (NSCLS), triple negative breast cancer (TNBC), and melanoma, but has limited expression on normal tissues. Interestingly, unlike other members of B7 family, HHLA2 is not expressed in mice or rats. HHLA2 functions as a T cell coinhibitory molecules as it inhibits the proliferation of activated CD4(+) and CD8(+) T cells and their cytokine production. Furthermore, HHLA2 is constitutively expressed on the surface of human monocytes and is induced on B cells after stimulation, however it is not inducible on T cells.

Pssm-ID: 409512 Cd Length: 107 Bit Score: 39.68 E-value: 2.01e-03

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1295 VTTPWMKDIVLPCKAVGDPSPAVKWMKDSN---------GTPSLVTID----GRRSIFS------NGSFIIRTVKAEDSG 1355
Cdd:cd16091    7 VVCLLSEDCILPCSFTPGSEVVIHWYKQDSdikvhsyyyGKDQLESQDqryrNRTSLFKdqisngNASLLLRRVQLQDEG 86

                         90       100
                 ....*....|....*....|.
gi 20127422 1356 YYSCIANNNWGSDEIILNLQV 1376
Cdd:cd16091   87 RYKCYTSTIIGNQESFVNLKV 107

Immunoglobulin domain I1 of the titin I-band and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin domain I1 of the titin I-band and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. The two sheets are linked together by a conserved disulfide bond between B strand and F strand. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The Ig I1 domain of the titin I-band is a member of the I-set Ig domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409543 [Multi-domain] Cd Length: 94 Bit Score: 39.33 E-value: 2.01e-03

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  690 PKFVVQPRDQDGIYGKAVILNCSAEGYPVPTIVWKFSkgaGVPqFQPIALNGRIQVLSNG---SLLIKHVVEEDSGYYLC 766
Cdd:cd20951    1 PEFIIRLQSHTVWEKSDAKLRVEVQGKPDPEVKWYKN---GVP-IDPSSIPGKYKIESEYgvhVLHIRRVTVEDSAVYSA 76


                 ....*..
gi 20127422  767 KVSNDVG 773
Cdd:cd20951   77 VAKNIHG 83

Fifth immunoglobulin (Ig)-like domain of Kirrel (kin of irregular chiasm-like) 3, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the fifth immunoglobulin (Ig)-like domain of Kirrel (kin of irregular chiasm-like) 3 (also known as Neph2). This protein has five Ig-like domains, one transmembrane domain, and a cytoplasmic tail. Included in this group is mammalian Kirrel (also known as Neph1), Kirrel2 (also known as Neph3), and Drosophila RST (also known as irregular chiasm C-roughest) protein. These proteins contain multiple Ig domains, have properties of cell adhesion molecules, and are important in organ development.

Pssm-ID: 319310 Cd Length: 98 Bit Score: 39.44 E-value: 2.04e-03

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  224 APSILDGFDHRKAMAGQRVELPCKALGHPEPD-YRWLKDNMPLE--LSGRF--------QKTVTGLLIENIRPSD-SGSY 291
Cdd:cd05758    1 GPPIITAEATQPAILGEKARLECLVFSSPPPDrIVWSWDEGFLEsgSSGRFsvetfptePGVISVLHISGTQRSDfQTSF 80

                         90
                 ....*....|....*..
gi 20127422  292 VCEVSNRYGTAKVIGRL 308
Cdd:cd05758   81 NCSAWNRFGEGTAIVSL 97

Fifth immunoglobulin (Ig) domain of contactin-1; The members here are composed of the fifth immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-1. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-1 is differentially expressed in tumor tissues and may through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409438 Cd Length: 89 Bit Score: 39.21 E-value: 2.04e-03

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 20127422  236 AMAGQRVELPCKALGHPEPDYRWLKDNMPLELSGRFQKTVTGLL-IENIRPSDSGSYVCEVSNRYGTAKVIGRLYV 310
Cdd:cd05852   14 AAKGGRVIIECKPKAAPKPKFSWSKGTELLVNNSRISIWDDGSLeILNITKLDEGSYTCFAENNRGKANSTGVLSV 89

First immunoglobulin (Ig) domain of Cluster of Differentiation (CD) 4; member of the V-set of IgSF domains; The members here are composed of the first immunoglobulin (Ig) domain of Cluster of Differentiation (CD) 4. CD4 and CD8 are the two primary co-receptor proteins found on the surface of T cells, and the presence of either CD4 or CD8 determines the function of the T cell. CD4 is found on helper T cells, where it is required for the binding of MHC (major histocompatibility complex) class II molecules, while CD8 is found on cytotoxic T cells, where it is required for the binding of MHC class I molecules. CD4 contains four immunoglobulin domains, with the first three included in this hierarchy. The fourth domain has a general Ig architecture, but has slight topological changes in the arrangement of beta strands relative to the other structures in this family and is not specifically included in the hierarchy.

Pssm-ID: 409487 Cd Length: 97 Bit Score: 39.45 E-value: 2.09e-03

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  238 AGQRVELPCKALGHPEPDYRW--------------LKDNMPLELSGRFQKTVTG-------LLIENIRPSDSGSYVCEVS 296
Cdd:cd07690    8 KGDTAELPCTASQKKSIQFHWknsnqikilgnqgsFLTKGPSKLNDRADSRRNLwdqgsfpLIIKNLKIEDSDTYICEVE 87


                 ..
gi 20127422  297 NR 298
Cdd:cd07690   88 DK 89

Immunoglobulin domain; Members of the immunoglobulin superfamily are found in hundreds of proteins of different functions. Examples include antibodies, the giant muscle kinase titin and receptor tyrosine kinases. Immunoglobulin-like domains may be involved in protein-protein and protein-ligand interactions.

Pssm-ID: 395002 Cd Length: 86 Bit Score: 39.10 E-value: 2.09e-03

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 20127422    318 ISPRKVKSSVGSQVSLSCSV-TGTEDQELSWYRNGE--ILNPGKNVRITGINHENLIMDHMVKSDGGAYQCFVR 388
Cdd:pfam00047    1 SAPPTVTVLEGDSATLTCSAsTGSPGPDVTWSKEGGtlIESLKVKHDNGRTTQSSLLISNVTKEDAGTYTCVVN 74

Immunoglobulin (Ig)-like domain found in Perlecan and similar proteins; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig)-like domain found in Perlecan. Perlecan is a large multi-domain heparin sulfate proteoglycan, important in tissue development and organogenesis. Perlecan can be represented as 5 major portions; its fourth major portion (domain IV) is a tandem repeat of immunoglobulin-like domains (Ig2-Ig15) which can vary in size due to alternative splicing. Perlecan binds many cellular and extracellular ligands. Its domain IV region has many binding sites. Some of these have been mapped at the level of individual Ig-like domains, including a site restricted to the Ig5 domain for heparin/sulfatide, a site restricted to the Ig3 domain for nidogen-1 and nidogen-2, a site restricted to Ig4-5 for fibronectin, and sites restricted to Ig2 and to Ig13-15 for fibulin-2. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409412 Cd Length: 85 Bit Score: 39.08 E-value: 2.14e-03

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 20127422  239 GQRVELPCKALGH-PEPDYRWLKDNMPLELSGR-FQKTVTgllIENIRPSDSGSYVCEVSNRYGTAKVIGRLY 309
Cdd:cd05754   16 GADVSFICRAKSKsPAYTLVWTRVNGTLPSRAMdFNGILT---IRNVQLSDAGTYVCTGSNMLDTDEATATLY 85

Immunoglobulin (Ig) constant domain of the complement receptor of the immunoglobulin superfamily (CRIg); The members here are composed of the Immunoglobulin (Ig) constant domain of the complement receptor of the immunoglobulin superfamily (CRIg). The N-terminal domain of CRIg (also referred to as Z39Ig and V-set and Ig domain-containing 4 (VSIG4)) belongs to the IgV family of immunoglobulin-like domains while the C-terminal domain of CRIg belongs to the IgC family of immunoglobulin-like domains. CRIg plays a role in the complement system, an inhibitor of the alternative pathway convertases, and a negative regulator of T cell activation. The Ig superfamily is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. Members of this group are components of immunoglobulin, neuroglia, cell surface glycoproteins such as T-cell receptors, CD2, CD4, CD8, and membrane glycoproteins such as butyrophilin and chondroitin sulfate proteoglycan core protein. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond.

Pssm-ID: 409504 Cd Length: 86 Bit Score: 38.97 E-value: 2.23e-03

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 20127422  239 GQRVELPCKALGHPEPDYRWLK----DNMPLELSgrfqkTVTGLLIENIRPSDSGSYVCEVSNRYGT 301
Cdd:cd16082   13 GMRISLQCQAWGSPPISYVWYKeqtnNQEPIKVA-----ALSTLLFKPAVVADSGSYFCTAKGRVGS 74

Third immunoglobulin (Ig) domain of contactin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409357 [Multi-domain] Cd Length: 88 Bit Score: 39.07 E-value: 2.27e-03

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 20127422  610 GQRVFIPCVVVSGDLPiTITWQK-DGRPIPGSLGVTIDNIdftssLRISNLSLMHNGNYTCIARNEAAAVEHQSQLIV 686
Cdd:cd04968   16 GQTVTLECFALGNPVP-QIKWRKvDGSPSSQWEITTSEPV-----LEIPNVQFEDEGTYECEAENSRGKDTVQGRIIV 87

First immunoglobulin (Ig) domain of contactin-2; member of the I-set of Ig superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-2-like. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-2 (TAG-1, axonin-1) facilitates cell adhesion by homophilic binding between molecules in apposed membranes. It may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module by contacts between IG domains 1 and 4, and domains 2 and 3. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-2 is also expressed in retinal amacrine cells in the developing chick retina, corresponding to the period of formation and maturation of AC processes. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409437 [Multi-domain] Cd Length: 97 Bit Score: 39.14 E-value: 2.31e-03

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 20127422  419 SPAEPVSLMCNVKGTPLPTITWTLDDDPILKGGSHRISQMitsEGNVVsylnISSSQ-VRDGGVYRCTANNSAGVVL 494
Cdd:cd05850   18 SAEEKVTLACRARASPPATYRWKMNGTELKMEPDSRYRLV---AGNLV----ISNPVkAKDAGSYQCLASNRRGTVV 87

immunoglobulin-like domain of telokin and similar proteins; a member of the I-set of IgSF domains; The members here are composed of the immunoglobulin (Ig) domain in telokin, the C-terminal domain of myosin light chain kinase which is identical to telokin, and similar proteins. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the telokin Ig domain lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409565 [Multi-domain] Cd Length: 88 Bit Score: 39.09 E-value: 2.32e-03

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  599 IQPFEFPRFSIGQRVFIPCVVVSGDLPiTITWQKDGRPIPGSLGVTID-NIDFTSSLRISNLSLMHNGNYTCIARNEAAA 677
Cdd:cd20973    1 IQTLRDKEVVEGSAARFDCKVEGYPDP-EVKWMKDDNPIVESRRFQIDqDEDGLCSLIISDVCGDDSGKYTCKAVNSLGE 79


                 ....*....
gi 20127422  678 VEHQSQLIV 686
Cdd:cd20973   80 ATCSAELTV 88

First immunoglobulin (Ig) domain of Cluster of Differentiation (CD) 4; member of the V-set of IgSF domains; The members here are composed of the first immunoglobulin (Ig) domain of Cluster of Differentiation (CD) 4. CD4 and CD8 are the two primary co-receptor proteins found on the surface of T cells, and the presence of either CD4 or CD8 determines the function of the T cell. CD4 is found on helper T cells, where it is required for the binding of MHC (major histocompatibility complex) class II molecules, while CD8 is found on cytotoxic T cells, where it is required for the binding of MHC class I molecules. CD4 contains four immunoglobulin domains, with the first three included in this hierarchy. The fourth domain has a general Ig architecture, but has slight topological changes in the arrangement of beta strands relative to the other structures in this family and is not specifically included in the hierarchy.

Pssm-ID: 409487 Cd Length: 97 Bit Score: 39.07 E-value: 2.33e-03

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 20127422 1305 LPCKAVGDPSPAVKWmKDSNGT------PSLVT---------IDGRRSIFSNGSF--IIRTVKAEDSGYYSC 1359
Cdd:cd07690   14 LPCTASQKKSIQFHW-KNSNQIkilgnqGSFLTkgpsklndrADSRRNLWDQGSFplIIKNLKIEDSDTYIC 84

First immunoglobulin (Ig) domain of contactin-1; member of the I-set of Ig superfamily domains; The members here are composed of the first immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-1. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma. This group belongs to the I-set of IgSF domains.

Pssm-ID: 409436 [Multi-domain] Cd Length: 95 Bit Score: 39.17 E-value: 2.45e-03

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 20127422 1303 IVLPCKAVGDPSPAVKWMKDsNGTPSLVTidGRRSIFSNGSFIIRTVKAEDSGYYSCIANNNWG---SDEIILNL 1374
Cdd:cd05849   22 VSVNCRARANPFPIYKWRKN-NLDIDLTN--DRYSMVGGNLVINNPDKYKDAGRYVCIVSNIYGkvrSREATLSF 93

agrin-responsive first immunoglobulin-like domains (Ig1) of the MuSK ectodomain; a member of the I-set of IgSF domains; The members here are composed of the first immunoglobulin-like domains (Ig1) of the Muscle-specific kinase (MuSK). MuSK is a receptor tyrosine kinase specifically expressed in skeletal muscle, where it plays a central role in the formation and maintenance of the neuromuscular junction (NMJ). MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. The activation of MUSK in myotubes regulates the formation of NMJs through the regulation of different processes including the specific expression of genes in subsynaptic nuclei, the reorganization of the actin cytoskeleton and the clustering of the acetylcholine receptors (AChR) in the postsynaptic membrane. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the MuSK lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409562 [Multi-domain] Cd Length: 92 Bit Score: 39.03 E-value: 2.49e-03

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 20127422  610 GQRVFIPCVVVSGDLPiTITWQKDG-RPIPGSLGVTIDNIDFTssLRISNLSLMHNGNYTCIARNEAA-AVEHQSQLIV 686
Cdd:cd20970   17 GENATFMCRAEGSPEP-EISWTRNGnLIIEFNTRYIVRENGTT--LTIRNIRRSDMGIYLCIASNGVPgSVEKRITLQV 92

Fourth immunoglobulin (Ig)-like domain of peroxidasin; The members here are composed of the fourth immunoglobulin (Ig)-like domain in peroxidasin. Peroxidasin has a peroxidase domain and interacting extracellular motifs containing four Ig-like domains. It has been suggested that peroxidasin is secreted, and has functions related to the stabilization of the extracellular matrix. It may play a part in various other important processes such as removal and destruction of cells which have undergone programmed cell death and protection of the organism against non-self.

Pssm-ID: 143223 Cd Length: 69 Bit Score: 38.32 E-value: 2.59e-03

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 20127422  613 VFIPCVVvSGDLPITITWQKDGRPIPGSLGVTIDNIDFtssLRISNLSLMHNGNYTCIARN 673
Cdd:cd05746    1 VQIPCSA-QGDPEPTITWNKDGVQVTESGKFHISPEGY---LAIRDVGVADQGRYECVARN 57

Immunoglobulin variable domain (IgV); The members here are composed of the immunoglobulin variable domain (IgV). The IgV family contains the standard Ig superfamily V-set AGFCC'C"/DEB domain topology, and are components of immunoglobulin (Ig) and T cell receptors. The basic structure of Ig molecules is a tetramer of two light chains and two heavy chains linked by disulfide bonds. In Ig, each chain is composed of one variable domain (IgV) and one or more constant domains (IgC); these names reflect the fact that the variability in sequences is higher in the variable domain than in the constant domain. Within the variable domain, there are regions of even more variability called the hypervariable or complementarity-determining regions (CDRs) which are responsible for antigen binding. A predominant feature of most Ig domains is the disulfide bridge connecting 2 beta-sheets with a tryptophan residue packed against the disulfide bond. Ig superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Typically, the V-set domains have A, B, E and, D strands in one sheet and A', G, F, C, C', and C" strands in the other.

Pssm-ID: 409355 [Multi-domain] Cd Length: 111 Bit Score: 39.62 E-value: 2.62e-03

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  704 GKAVILNCSAEG-YPVPTIVWKFSKGAGVPQF----------QPIALNGRIQVLSNG----SLLIKHVVEEDSGYYLCKV 768
Cdd:cd00099   13 GESVTLSCEVSSsFSSTYIYWYRQKPGQGPEFliylssskgkTKGGVPGRFSGSRDGtssfSLTISNLQPEDSGTYYCAV 92


                 .
gi 20127422  769 S 769
Cdd:cd00099   93 S 93

Second Ig-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of the giant muscle protein titin Z1z2 in the sarcomeric Z-disk and similar proteins. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structure of the titin Z1z2 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409564 [Multi-domain] Cd Length: 91 Bit Score: 38.72 E-value: 2.70e-03

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  320 PRKVKSSVGSQVSLSCSVTGTEDQELSWYRNGEILNPGKNVRI-TGINHENLIMDHMVKSDGGAYQCF----VRKDKLSA 394
Cdd:cd20972    8 LRSQEVAEGSKVRLECRVTGNPTPVVRWFCEGKELQNSPDIQIhQEGDLHSLIIAEAFEEDTGRYSCLatnsVGSDTTSA 87


                 ....
gi 20127422  395 QDYV 398
Cdd:cd20972   88 EIFV 91

First immunoglobulin-like domains A168 within the A-band segment of human cardiac titin, and similar domains; a member of the I-set of IgSF domains; The members here are composed of the first immunoglobulin-like domain A168 within the A-band segment of human cardiac titin. Titin is a key component in the assembly and functioning of vertebrate striated muscles. By providing connections at the level of individual microfilaments, it contributes to the fine balance of forces between the two halves of the sarcomere. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Unlike the V-set, one of the distinctive features of I-set domains is the lack of a C" strand. The structures of the titin-A168169 lacks this strand and thus it belongs to the I-set of the IgSF. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins titin, telokin, and twitchin, the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D that is involved in axonal guidance, immune function and angiogenesis.

Pssm-ID: 409563 Cd Length: 93 Bit Score: 38.99 E-value: 2.74e-03

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 20127422  421 AEPVSLMCNVKGTPLPTITWTLDDDPILKGGSHrisqmITSEGNV-VSYLNISSSQVR-DGGVYRCTANNSAG 491
Cdd:cd20971   16 QSNATLVCKVTGHPKPIVKWYRQGKEIIADGLK-----YRIQEFKgGYHQLIIASVTDdDATVYQVRATNQGG 83

Third immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule 1 (NCAM-1); member of the I-set of IgSF domains; The members here are composed of the third immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule (NCAM-1). NCAM plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM), and heterophilic (NCAM-non-NCAM), interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves Ig1, Ig2, and Ig3. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions) through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain.

Pssm-ID: 143207 [Multi-domain] Cd Length: 95 Bit Score: 39.14 E-value: 2.86e-03

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 20127422  504 PASIRPMK---NITAIAGRDTYIHCRVIGYPYYSIKWYKNSNLLPFNHRQVAFENNGT-LKLSDVQKEvDEGEYTC 575
Cdd:cd05730    1 PPTIRARQsevNATANLGQSVTLACDADGFPEPTMTWTKDGEPIESGEEKYSFNEDGSeMTILDVDKL-DEAEYTC 75

Fifth immunoglobulin (Ig) domain of contactin; The members here are composed of the fifth immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409358 [Multi-domain] Cd Length: 89 Bit Score: 38.60 E-value: 2.86e-03

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 20127422  610 GQRVFIPCVVVSGDLPiTITWQKDGRPIPGSLGVTI-DNidftSSLRISNLSLMHNGNYTCIARN 673
Cdd:cd04969   17 GGDVIIECKPKASPKP-TISWSKGTELLTNSSRICIlPD----GSLKIKNVTKSDEGKYTCFAVN 76

Fifth immunoglobulin (Ig) domain of contactin; The members here are composed of the fifth immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409358 [Multi-domain] Cd Length: 89 Bit Score: 38.60 E-value: 3.09e-03

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 20127422  311 KQPLKatispRKVKSSVGSQVSLSCSVTGTEDQELSWYRNGEILNPGKnvRITGINHENLIMDHMVKSDGGAYQCF 386
Cdd:cd04969    5 LNPVK-----KKILAAKGGDVIIECKPKASPKPTISWSKGTELLTNSS--RICILPDGSLKIKNVTKSDEGKYTCF 73

C-terminal immunoglobulin-like domain of the myosin-associated giant protein kinase Twitchin, and similar domains; member of the I-set IgSF domains; The members here are composed of the C-terminal immunoglobulin-like domain of the myosin-associated giant protein kinase Twitchin and similar proteins, including Caenorhabditis elegans and Aplysia californica Twitchin, Drosophila melanogaster Projectin, and similar proteins. These are very large muscle proteins containing multiple immunoglobulin (Ig)-like and fibronectin type III (FN3) domains and a single kinase domain near the C-terminus. In humans these proteins are called Titin. The Ig superfamily (IgSF) is a heterogenous group of proteins, built on a common fold comprised of a sandwich of two beta sheets. IgSF domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. The Ig-like domain of the Twitchin is a member of the I-set IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand but lack a C" strand. I-set domains are found in several cell adhesion molecules (such as VCAM, ICAM, and MADCAM), and are also present in numerous other diverse protein families, including several tyrosine-protein kinase receptors, the hemolymph protein hemolin, the muscle proteins (titin, telokin, and twitchin), the neuronal adhesion molecule axonin-1, and the signaling molecule semaphorin 4D.

Pssm-ID: 409541 [Multi-domain] Cd Length: 89 Bit Score: 38.47 E-value: 3.24e-03

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  791 TSYPNTTLATQGQKKEMSCTAHGEKPIIVRWEKEDRIIN---PEMARYLVSTkevgeeviSTLQILPTVREDSGFFSCHA 867
Cdd:cd20949    3 TENAYVTTVKEGQSATILCEVKGEPQPNVTWHFNGQPISasvADMSKYRILA--------DGLLINKVTQDDTGEYTCRA 74

                         90
                 ....*....|....*
gi 20127422  868 INSYGEDRGIIQLTV 882
Cdd:cd20949   75 YQVNSIASDMQERTV 89

Immunoglobulin (Ig)-like I-set domain of Neural Cell Adhesion Molecule 2 (NCAM-2); The members here are composed of the fourth Ig domain of Neural Cell Adhesion Molecule NCAM-2 (also known as OCAM/mamFas II and RNCAM). NCAM-2 is organized similarly to NCAM, including five N-terminal Ig-like domains and two fibronectin type III domains. NCAM-2 is differentially expressed in the developing and mature olfactory epithelium (OE), and may function like NCAM, as an adhesion molecule. One of the unique features of I-set domains is the lack of a C" strand. The structures of this group show that the Ig domain lacks this strand and thus is a member of the I-set of Ig domains.

Pssm-ID: 143278 [Multi-domain] Cd Length: 98 Bit Score: 38.80 E-value: 3.27e-03

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422 1303 IVLPCKAVGDPSPAVKWMKDSNG---TPSLVTIDGR---RSIFSNGSFIIRTVKAEDSGYYSCIANNNWG 1366
Cdd:cd05870   19 ATLSCKAEGEPIPEITWKRASDGhtfSEGDKSPDGRievKGQHGESSLHIKDVKLSDSGRYDCEAASRIG 88

Third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM), and similar domains; The members here are composed of the third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, and spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM and human neurofascin.

Pssm-ID: 409394 [Multi-domain] Cd Length: 83 Bit Score: 38.16 E-value: 3.51e-03

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  628 ITWQKDGRPIPGSLGVTiDNidFTSSLRISNLSLMHNGNYTCIARNEAAAVEHQSQLIVR 687
Cdd:cd05731   27 IRWIKLGGELPKGRTKF-EN--FNKTLKIENVSEADSGEYQCTASNTMGSARHTISVTVE 83

Fifth immunoglobulin (Ig) domain of contactin; The members here are composed of the fifth immunoglobulin (Ig) domain of contactins. Contactins are neural cell adhesion molecules and are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. The first four Ig domains form the intermolecular binding fragment, which arranges as a compact U-shaped module via contacts between Ig domains 1 and 4, and between Ig domains 2 and 3. Contactin-2 (TAG-1, axonin-1) may play a part in the neuronal processes of neurite outgrowth, axon guidance and fasciculation, and neuronal migration. This group also includes contactin-1 and contactin-5. The different contactins show different expression patterns in the central nervous system. During development and in adulthood, contactin-2 is transiently expressed in subsets of central and peripheral neurons. Contactin-5 is expressed specifically in the rat postnatal nervous system, peaking at about 3 weeks postnatal, and a lack of contactin-5 (NB-2) results in an impairment of neuronal activity in the rat auditory system. Contactin-5 is highly expressed in the adult human brain in the occipital lobe and in the amygdala. Contactin-1 is differentially expressed in tumor tissues and may, through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409358 [Multi-domain] Cd Length: 89 Bit Score: 38.60 E-value: 3.55e-03

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  408 KIISAFSEKVVSPAEPvslmcnvKGTPLPTITWTLDDDpILKGGShRISqmITSEGNvvsyLNISSSQVRDGGVYRCTAN 487
Cdd:cd04969   11 KILAAKGGDVIIECKP-------KASPKPTISWSKGTE-LLTNSS-RIC--ILPDGS----LKIKNVTKSDEGKYTCFAV 75


                 ....
gi 20127422  488 NSAG 491
Cdd:cd04969   76 NFFG 79

Fibronectin type 3 domain; One of three types of internal repeat within the plasma protein, fibronectin. The tenth fibronectin type III repeat contains a RGD cell recognition sequence in a flexible loop between 2 strands. Type III modules are present in both extracellular and intracellular proteins.

Pssm-ID: 214495 [Multi-domain] Cd Length: 83 Bit Score: 38.36 E-value: 3.56e-03

                            10        20        30        40        50        60        70
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 20127422    1486 SINTTRVRLNligW-----NDGGCPITSFTLEYRPFGTTvWTTAQRTSLSKSYILYDLQEATWYELQMRVCNSAG 1555
Cdd:smart00060   11 DVTSTSVTLS---WepppdDGITGYIVGYRVEYREEGSE-WKEVNVTPSSTSYTLTGLKPGTEYEFRVRAVNGAG 81

Third immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule 1 (NCAM-1); member of the I-set of IgSF domains; The members here are composed of the third immunoglobulin (Ig)-like domain of Neural Cell Adhesion Molecule (NCAM-1). NCAM plays important roles in the development and regeneration of the central nervous system, in synaptogenesis and neural migration. NCAM mediates cell-cell and cell-substratum recognition and adhesion via homophilic (NCAM-NCAM), and heterophilic (NCAM-non-NCAM), interactions. NCAM is expressed as three major isoforms having different intracellular extensions. The extracellular portion of NCAM has five N-terminal Ig-like domains and two fibronectin type III domains. The double zipper adhesion complex model for NCAM homophilic binding involves Ig1, Ig2, and Ig3. By this model, Ig1 and Ig2 mediate dimerization of NCAM molecules situated on the same cell surface (cis interactions), and Ig3 domains mediate interactions between NCAM molecules expressed on the surface of opposing cells (trans interactions) through binding to the Ig1 and Ig2 domains. The adhesive ability of NCAM is modulated by the addition of polysialic acid chains to the fifth Ig-like domain.

Pssm-ID: 143207 [Multi-domain] Cd Length: 95 Bit Score: 38.76 E-value: 3.57e-03

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  627 TITWQKDGRPIPGSLGVTIDNIDfTSSLRISNLSLMHNGNYTCIARNEAAAVEHQSQLIV 686
Cdd:cd05730   34 TMTWTKDGEPIESGEEKYSFNED-GSEMTILDVDKLDEAEYTCIAENKAGEQEAEIHLKV 92

Fourth immunoglobulin (Ig)-like domain in neogenin, and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the fourth immunoglobulin (Ig)-like domain in neogenin and related proteins. Neogenin is a cell surface protein which is expressed in the developing nervous system of vertebrate embryos in the growing nerve cells. It is also expressed in other embryonic tissues, and may play a general role in developmental processes such as cell migration, cell-cell recognition, and tissue growth regulation. Included in this group is the tumor suppressor protein DCC which is deleted in colorectal carcinoma. DCC and neogenin each have four Ig-like domains followed by six fibronectin type III domains, a transmembrane domain, and an intracellular domain. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409388 Cd Length: 84 Bit Score: 38.33 E-value: 3.62e-03

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 20127422  707 VILNCSAEGYPVPTIVWKFSKGAGVPqfqpialNGRIQVLSNGSLLIKHVVEEDSGYYLCKVSNDVG 773
Cdd:cd05723   15 IVFECEVTGKPTPTVKWVKNGDVVIP-------SDYFKIVKEHNLQVLGLVKSDEGFYQCIAENDVG 74

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor, and similar domains; member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor. FGF receptors bind FGF signaling polypeptides. FGFs participate in multiple processes such as morphogenesis, development, and angiogenesis. FGFs bind to four FGF receptor tyrosine kinases (FGFR1, FGFR2, FGFR3, FGFR4). Receptor diversity is controlled by alternative splicing producing splice variants with different ligand binding characteristics and different expression patterns. FGFRs have an extracellular region comprised of three Ig-like domains, a single transmembrane helix, and an intracellular tyrosine kinase domain. Ligand binding and specificity reside in the Ig-like domains 2 and 3, and the linker region that connects these two. FGFR activation and signaling depend on FGF-induced dimerization, a process involving cell surface heparin or heparin sulfate proteoglycans. This group also contains fibroblast growth factor (FGF) receptor like-1(FGFRL1). FGFRL1 does not have a protein tyrosine kinase domain at its C-terminus; neither does its cytoplasmic domain appear to interact with a signaling partner. It has been suggested that FGFRL1 may not have any direct signaling function, but instead acts as a decoy receptor trapping FGFs and preventing them from binding other receptors.

Pssm-ID: 409393 [Multi-domain] Cd Length: 95 Bit Score: 38.74 E-value: 3.66e-03

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 20127422  327 VGSQVSLSCSVTGTEDQELSWYRNGEILNPGKNVRITGI--NHENLIMDHMVKSDGGAYQCFV 387
Cdd:cd05729   18 AANKVRLECGAGGNPMPNITWLKDGKEFKKEHRIGGTKVeeKGWSLIIERAIPRDKGKYTCIV 80

Third immunoglobulin-like domain of the human WFIKKN (WAP, follistatin, immunoglobulin, Kunitz and NTR domain-containing protein), and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin-like domain of the human WFIKKN (WAP, follistatin, immunoglobulin, Kunitz and NTR domain-containing protein) and similar proteins. WFIKKN is a secreted protein that consists of multiple types of protease inhibitory modules, including two tandem Kunitz-type protease inhibitor-domains. The Ig superfamily is a heterogenous group of proteins built on a common fold comprised of a sandwich of two beta sheets. Members of the Ig superfamily are components of immunoglobulin, neuroglia, cell surface glycoproteins, such as T-cell receptors, CD2, CD4, CD8, and membrane glycoproteins, such as butyrophilin and chondroitin sulfate proteoglycan core protein. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409422 [Multi-domain] Cd Length: 95 Bit Score: 38.68 E-value: 3.92e-03

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  225 PSILDGFDHRKAMAGQRVELPCKALGHPEPDYRWLK-----DNM---PLELSGRFQKTVTG-LLIENIRPSDSGSYVCEV 295
Cdd:cd05765    1 PALVNSPTHQTVKVGETASFHCDVTGRPQPEITWEKqvpgkENLimrPNHVRGNVVVTNIGqLVIYNAQPQDAGLYTCTA 80


                 ....*....
gi 20127422  296 SNRYGTAKV 304
Cdd:cd05765   81 RNSGGLLRA 89

C5 immunoglobulin (Ig) domain of cardiac myosin binding protein C (MyBP-C); The members here are composed of the C5 immunoglobulin (Ig) domain of cardiac myosin binding protein C (MyBP-C). MyBP-C consists of repeated domains, Ig and fibronectin type 3, and various linkers. Three isoforms of MYBP-C exist: slow-skeletal (ssMyBP-C), fast-skeletal (fsMyBP-C), and cardiac (cMyBP-C). cMYBP-C has insertions between and inside domains and an additional cardiac-specific Ig domain at the N-terminus. For cMYBP_C an interaction has been demonstrated between this C5 domain and the Ig C8 domain.

Pssm-ID: 409475 Cd Length: 86 Bit Score: 38.28 E-value: 3.97e-03

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 20127422 1311 GDPSPAVKWMKdsnGTPSLVTIDGRRSIFSN---GSFIIRTVKAEDSGYYSCIANNNWGSDEIILNLQV 1376
Cdd:cd05894   21 GEPAPTVTWSR---GDKAFTATEGRVRVESYkdlSSFVIEGAEREDEGVYTITVTNPVGEDHASLFVKV 86

Immunoglobulin Variable (V) domain of the Coxsackievirus and Adenovirus Receptor (CAR), and similar proteins; The members here are composed of the Variable (V) domain of the Coxsackievirus and Adenovirus Receptor (CAR), and similar proteins. CAR, which is encoded by human CXADR gene, is a cell adhesion molecule of the Immunoglobulin (Ig) superfamily. The CAR acts as a type I membrane receptor for group B1-B6 coxsackie viruses and subgroup C adenoviruses. For instance, adenovirus interacts with the coxsackievirus and adenovirus receptor to enter epithelial airway cells. The CAR is also shown to be involved in physiological processes such as neuronal and heart development, epithelial tight junction integrity, and tumor suppression. The CAR is a component of the epithelial apical junction complex that may function as a homophilic cell adhesion molecule and is essential for tight junction integrity. The CAR is also involved in transepithelial migration of leukocytes through adhesive interactions with JAML a transmembrane protein of the plasma membrane of leukocytes. The interaction between both receptors also mediates the activation of gamma-delta T-cells, a subpopulation of T-cells residing in epithelia and involved in tissue homeostasis and repair. The CAR is composed of one V-set and one C2-set Ig module, a single transmembrane helix, and an intracellular domain. This group belongs to the V-set of IgSF domains, having A, B, E and D strands in one beta-sheet and A', G, F, C, C' and C" in the other

Pssm-ID: 409552 Cd Length: 114 Bit Score: 38.97 E-value: 4.22e-03

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  235 KAMAGQRVELPCK-ALGHPEP---DYRWLK-------------------DNMPLELSGRFQKTVT------GLLIENIRP 285
Cdd:cd20960   11 KKVAGENVTLPCHhQLGLEDQgtlDIEWLLlpsdkvekvvitysgdrvyNHYYPALKGRVAFTSNdlsgdaSLNISNLKL 90

                         90       100
                 ....*....|....*....|..
gi 20127422  286 SDSGSYVCEVSN--RYGTAKVI 305
Cdd:cd20960   91 SDTGTYQCKVKKapGYAWSKIT 112

Third immunoglobulin (Ig)-like domain of peroxidasin; The members here are composed of the third immunoglobulin (Ig)-like domain in peroxidasin. Peroxidasin has a peroxidase domain and interacting extracellular motifs containing four Ig-like domains. It has been suggested that peroxidasin is secreted and has functions related to the stabilization of the extracellular matrix. It may play a part in various other important processes such as removal and destruction of cells which have undergone programmed cell death and protection of the organism against non-self.

Pssm-ID: 143222 [Multi-domain] Cd Length: 74 Bit Score: 38.00 E-value: 4.29e-03

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  424 VSLMCNVKGTPLPTITWTldddpilKGGSH----RISQMITSegnvvSYLNISSSQVRDGGVYRCTANNSAGVVLYQARI 499
Cdd:cd05745    5 VDFLCEAQGYPQPVIAWT-------KGGSQlsvdRRHLVLSS-----GTLRISRVALHDQGQYECQAVNIVGSQRTVAQL 72


                 ..
gi 20127422  500 NV 501
Cdd:cd05745   73 TV 74

Immunoglobulin (Ig)-like I-set domain of Neural Cell Adhesion Molecule 2 (NCAM-2); The members here are composed of the fourth Ig domain of Neural Cell Adhesion Molecule NCAM-2 (also known as OCAM/mamFas II and RNCAM). NCAM-2 is organized similarly to NCAM, including five N-terminal Ig-like domains and two fibronectin type III domains. NCAM-2 is differentially expressed in the developing and mature olfactory epithelium (OE), and may function like NCAM, as an adhesion molecule. One of the unique features of I-set domains is the lack of a C" strand. The structures of this group show that the Ig domain lacks this strand and thus is a member of the I-set of Ig domains.

Pssm-ID: 143278 [Multi-domain] Cd Length: 98 Bit Score: 38.42 E-value: 4.78e-03

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 20127422  236 AMAGQRVELPCKALGHPEPDYRWLK----------DNMP---LELSGRFQKTVtgLLIENIRPSDSGSYVCEVSNRYG 300
Cdd:cd05870   13 TVENGAATLSCKAEGEPIPEITWKRasdghtfsegDKSPdgrIEVKGQHGESS--LHIKDVKLSDSGRYDCEAASRIG 88

First immunoglobulin (Ig)-like domain of carcinoembryonic antigen (CEA) related cell adhesion molecule (CEACAM); The members here are composed of the immunoglobulin (Ig)-like domain 1 in carcinoembryonic antigen (CEA) related cell adhesion molecule (CEACAM) proteins. The CEA family is a group of anchored or secreted glycoproteins, expressed by epithelial cells, leukocytes, endothelial cells, and placenta. The CEA family is divided into the CEACAM and pregnancy-specific glycoprotein (PSG) subfamilies. This group represents the CEACAM subfamily. CEACAM1 has many important cellular functions: it is a cell adhesion molecule and a signaling molecule that regulates the growth of tumor cells, an angiogenic factor, and a receptor for bacterial and viral pathogens, including mouse hepatitis virus (MHV). In mice, four isoforms of CEACAM1 generated by alternative splicing have either two (D1, D4) or four (D1-D4) Ig-like domains on the cell surface.

Pssm-ID: 409430 Cd Length: 105 Bit Score: 38.40 E-value: 4.80e-03

                         10        20
                 ....*....|....*....|....
gi 20127422  741 GRIQVLSNGSLLIKHVVEEDSGYY 764
Cdd:cd05774   62 GRETIYPNGSLLIQNVTQKDTGFY 85

IL-beta-binding protein; Provisional

Pssm-ID: 165149 [Multi-domain] Cd Length: 326 Bit Score: 41.54 E-value: 4.86e-03

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422   272 QKTVTGLLIENIRPSDSGSYVCEVSNRYGTAKVIGRLYVKQPLKATISPRKVK------SSVGSQVSLSCSVT---GTED 342
Cdd:PHA02785  173 QRTPGIITIEDVRKNDAGYYTCVLKYIYGDKTYNVTRIVKLEVRDRIIPPTMQlpegvvTSIGSNLTIACRVSlrpPTTD 252

                          90
                  ....*....|
gi 20127422   343 QELSWYRNGE 352
Cdd:PHA02785  253 ADVFWISNGM 262

Interferon-alpha/beta receptor, fibronectin type III; Members of this family adopt a secondary structure consisting of seven beta-strands arranged in an immunoglobulin-like beta-sandwich, in a Greek-key topology. They are required for binding to interferon-alpha.

Pssm-ID: 462746 Cd Length: 103 Bit Score: 38.48 E-value: 4.96e-03

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 20127422   1124 FRVIYWANlmdGELGEIKNITTTQPSLELDGLEKYTNYSIQVLAFTRAGD--GVRSEQIFTRTK 1185
Cdd:pfam09294   43 YRVSYWKN---SSNGEKKNTTSTNSFVVLSDLEPGTTYCVSVQAFSPLDNksSQRSPPQCIRTT 103

Third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM); The members here are composed of the third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains, five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM.

Pssm-ID: 409460 [Multi-domain] Cd Length: 83 Bit Score: 37.97 E-value: 5.05e-03

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  414 SEKVVSPAEPVSLMCNVKGTPLPTITWTLDDDPILKGGshrisqmiTSEGNVVSYLNISSSQVRDGGVYRCTANNSAGVV 493
Cdd:cd05876    3 SSLVALRGQSLVLECIAEGLPTPTVKWLRPSGPLPPDR--------VKYQNHNKTLQLLNVGESDDGEYVCLAENSLGSA 74

Fifth immunoglobulin (Ig) domain of contactin-1; The members here are composed of the fifth immunoglobulin (Ig) domain of the neural cell adhesion molecule contactin-1. Contactins are comprised of six Ig domains followed by four fibronectin type III (FnIII) domains anchored to the membrane by glycosylphosphatidylinositol. Contactin-1 is differentially expressed in tumor tissues and may through a RhoA mechanism, facilitate invasion and metastasis of human lung adenocarcinoma.

Pssm-ID: 409438 Cd Length: 89 Bit Score: 38.06 E-value: 5.23e-03

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 20127422  509 PM-KNITAIAGRDTYIHCRVIGYPYYSIKWYKNSNLLpFNHRQVAFENNGTLKLSDVQKeVDEGEYTC 575
Cdd:cd05852    7 PMkKKILAAKGGRVIIECKPKAAPKPKFSWSKGTELL-VNNSRISIWDDGSLEILNITK-LDEGSYTC 72

Immunoglobulin variable domain (IgV); The members here are composed of the immunoglobulin variable domain (IgV). The IgV family contains the standard Ig superfamily V-set AGFCC'C"/DEB domain topology, and are components of immunoglobulin (Ig) and T cell receptors. The basic structure of Ig molecules is a tetramer of two light chains and two heavy chains linked by disulfide bonds. In Ig, each chain is composed of one variable domain (IgV) and one or more constant domains (IgC); these names reflect the fact that the variability in sequences is higher in the variable domain than in the constant domain. Within the variable domain, there are regions of even more variability called the hypervariable or complementarity-determining regions (CDRs) which are responsible for antigen binding. A predominant feature of most Ig domains is the disulfide bridge connecting 2 beta-sheets with a tryptophan residue packed against the disulfide bond. Ig superfamily (IgSF) domains can be divided into 4 main classes based on their structures and sequences: the Variable (V), Constant 1 (C1), Constant 2 (C2), and Intermediate (I) sets. Typically, the V-set domains have A, B, E and, D strands in one sheet and A', G, F, C, C', and C" strands in the other.

Pssm-ID: 409355 [Multi-domain] Cd Length: 111 Bit Score: 38.47 E-value: 5.64e-03

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 20127422  238 AGQRVELPCKALGHPEPD----YRWLKDNMPLEL--------------SGRFQKTVTG-----LLIENIRPSDSGSYVCE 294
Cdd:cd00099   12 EGESVTLSCEVSSSFSSTyiywYRQKPGQGPEFLiylssskgktkggvPGRFSGSRDGtssfsLTISNLQPEDSGTYYCA 91

                         90
                 ....*....|.
gi 20127422  295 VSNRYGTAKVI 305
Cdd:cd00099   92 VSESGGTDKLT 102

Third immunoglobulin-like domain of the human WFIKKN (WAP, follistatin, immunoglobulin, Kunitz and NTR domain-containing protein), and similar domains; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the third immunoglobulin-like domain of the human WFIKKN (WAP, follistatin, immunoglobulin, Kunitz and NTR domain-containing protein) and similar proteins. WFIKKN is a secreted protein that consists of multiple types of protease inhibitory modules, including two tandem Kunitz-type protease inhibitor-domains. The Ig superfamily is a heterogenous group of proteins built on a common fold comprised of a sandwich of two beta sheets. Members of the Ig superfamily are components of immunoglobulin, neuroglia, cell surface glycoproteins, such as T-cell receptors, CD2, CD4, CD8, and membrane glycoproteins, such as butyrophilin and chondroitin sulfate proteoglycan core protein. A predominant feature of most Ig domains is a disulfide bridge connecting the two beta-sheets with a tryptophan residue packed against the disulfide bond. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409422 [Multi-domain] Cd Length: 95 Bit Score: 37.91 E-value: 5.79e-03

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 20127422 1307 CKAVGDPSPAVKWMKDSNGTPSLVT----IDGRRSIFSNGSFIIRTVKAEDSGYYSCIANNNWGS 1367
Cdd:cd05765   22 CDVTGRPQPEITWEKQVPGKENLIMrpnhVRGNVVVTNIGQLVIYNAQPQDAGLYTCTARNSGGL 86

Immunoglobulin (Ig)-like domain of epithelial V-like antigen (EVA) 1; The members here are composed of the immunoglobulin (Ig) domain of epithelial V-like antigen 1 (EVA 1). EVA is also known as myelin protein zero-like 2. EVA is an adhesion molecule and may play a role in the structural organization of the thymus and early lymphocyte development.

Pssm-ID: 409464 Cd Length: 116 Bit Score: 38.66 E-value: 5.94e-03

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gi 20127422  249 LGHPEPDYRWLKDNMPlELSGRFQKTVT----------GLLIENIRPSDSGSYVCEVSNRYGTAKVIGRLYVK 311
Cdd:cd05880   44 GGREESVFYYHKRPYP-PPDGRFKGRVVwdgnimrrdaSILIWQLQPTDNGTYTCQVKNPPDVHGPIGEIRLR 115

Immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM) and similar proteins; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the first immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, or spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains NrCAM [Ng(neuronglia)CAM-related cell adhesion molecule], which is primarily expressed in the nervous system, and human neurofascin. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lacks a C" strand.

Pssm-ID: 409396 [Multi-domain] Cd Length: 94 Bit Score: 38.16 E-value: 6.06e-03

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gi 20127422  244 LPCKALGHPEPDYRWLKDNMPLEL-----------SGRFQKTVTGLLIENIRpsdsGSYVCEVSNRYGTA 302
Cdd:cd05733   21 IKCEAKGNPQPTFRWTKDGKFFDPakdprvsmrrrSGTLVIDNHNGGPEDYQ----GEYQCYASNELGTA 86

Immunoglobulin like; IG domains that cannot be classified into one of IGv1, IGc1, IGc2, IG.

Pssm-ID: 214653 [Multi-domain] Cd Length: 85 Bit Score: 37.87 E-value: 6.20e-03

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gi 20127422      44 VPCPAAGIPPVTLRWYLATGEEIYDVPG--IRHVHPNGTLQIFPFppssfsTLIHDNTYYCTAENPSGKIRS 113
Cdd:smart00410   14 LSCEASGSPPPEVTWYKQGGKLLAESGRfsVSRSGSTSTLTISNV------TPEDSGTYTCAATNSSGSASS 79

Second immunoglobulin (Ig)-like domain of protein tyrosine kinase (PTK) 7; The members here are composed of the second immunoglobulin (Ig)-like domain in protein tyrosine kinase (PTK) 7, also known as CCK4. PTK7 is a subfamily of the receptor protein tyrosine kinase family, and is referred to as an RPTK-like molecule. RPTKs transduce extracellular signals across the cell membrane and play important roles in regulating cell proliferation, migration, and differentiation. PTK7 is organized as an extracellular portion having seven Ig-like domains, a single transmembrane region, and a cytoplasmic tyrosine kinase-like domain. PTK7 is considered a pseudokinase as it has several unusual residues in some of the highly conserved tyrosine kinase (TK) motifs; it is predicted to lack TK activity. PTK7 may function as a cell-adhesion molecule. PTK7 mRNA is expressed at high levels in placenta, melanocytes, liver, lung, pancreas, and kidney. PTK7 is overexpressed in several cancers, including melanoma and colon cancer lines.

Pssm-ID: 409417 Cd Length: 95 Bit Score: 37.99 E-value: 6.31e-03

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gi 20127422 1303 IVLPCKAVGDPSPAVKWMKDsnGTPsLVTIDGRRSIFSNG-SFIIRTVKAEDSGYYSCIANNNWGS 1367
Cdd:cd05760   19 VTLRCHIDGHPRPTYQWFRD--GTP-LSDGQGNYSVSSKErTLTLRSAGPDDSGLYYCCAHNAFGS 81

Second immunoglobulin (Ig)-like domain of interleukin-1 receptor (IL1R), and similar domains; The members here are composed of the second immunoglobulin (Ig)-like domain of interleukin-1 receptor (IL1R; also known as cluster of differentiation (CD) 121). IL-1 alpha and IL-1 beta are cytokines which participate in the regulation of inflammation, immune responses, and hematopoiesis. These cytokines bind to the IL-1 receptor type 1 (IL1R1), which is activated on additional association with interleukin-1 receptor accessory protein (IL1RAP). IL-1 also binds a second receptor designated type II (IL1R2). Mature IL1R1 consists of three IG-like domains, a transmembrane domain, and a large cytoplasmic domain. Mature IL1R2 is organized similarly except that it has a short cytoplasmic domain. The latter does not initiate signal transduction. A naturally occurring cytokine IL-1RA (IL-1 receptor antagonist) is widely expressed and binds to IL-1 receptors, inhibiting the binding of IL-1 alpha and IL-1 beta. This group also contains ILIR-like 1 (IL1R1L) which maps to the same chromosomal location as IL1R1 and IL1R2.

Pssm-ID: 409415 Cd Length: 92 Bit Score: 37.69 E-value: 6.69e-03

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gi 20127422  738 ALNGRIQVLSNGS-LLIKHVVEEDSGYYLCKVS---NDVGADVSKSMYLTVK 785
Cdd:cd05757   40 PLQGDKRFIPKGSkLLIQNVTEEDAGNYTCKFTythNGKQYNVTRTISLTVT 91

Second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor_like-1(FGFRL1); member of the I-set of IgSF domains; The members here are composed of the second immunoglobulin (Ig)-like domain of fibroblast growth factor (FGF) receptor like-1(FGFRL1). FGFRL1 is comprised of a signal peptide, three extracellular Ig-like modules, a transmembrane segment, and a short intracellular domain. FGFRL1 is expressed preferentially in skeletal tissues. Similar to FGF receptors, the expressed protein interacts specifically with heparin and with FGF2. FGFRL1 does not have a protein tyrosine kinase domain at its C-terminus; neither does its cytoplasmic domain appear to interact with a signaling partner. It has been suggested that FGFRL1 may not have any direct signaling function, but instead acts as a decoy receptor trapping FGFs and preventing them from binding other receptors.

Pssm-ID: 409442 Cd Length: 92 Bit Score: 37.92 E-value: 7.01e-03

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gi 20127422  596 PPFIQPFEFPRFSI----GQRVFIPCVVvSGDLPITITWQKDGRPI-PGSLGvtiDNIDFTSSLRISNLSLMHNGNYTCI 670
Cdd:cd05856    1 PRFTQPAKMRRRVIarpvGSSVRLKCVA-SGNPRPDITWLKDNKPLtPPEIG---ENKKKKWTLSLKNLKPEDSGKYTCH 76


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gi 20127422  671 ARNEAAAV 678
Cdd:cd05856   77 VSNRAGEI 84

Immunoglobulin (Ig)-like domain of the class IV semaphorin Sema4B; The members here are composed of the immunoglobulin (Ig)-like domain of Sema4B and similar proteins. Sema4B is a Class IV semaphorin. Semaphorins are classified based on structural features additional to the Sema domain. Sema4B has extracellular Sema and Ig domains, a transmembrane domain, and a short cytoplasmic domain. Sema4B has been shown to preferentially regulate the development of the postsynaptic specialization at the glutamatergic synapses. This cytoplasmic domain includes a PDZ-binding motif upon which the synaptic localization of Sem4B is dependent. Sema4B is a ligand of CLCP1. CLCP1 was identified in an expression profiling analysis, which compared a highly metastic lung cancer subline with its low metastic parental line. Sema4B was shown to promote CLCP1 endocytosis and their interaction is a potential target for therapeutic intervention of metastasis.

Pssm-ID: 409456 Cd Length: 86 Bit Score: 37.42 E-value: 7.47e-03

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gi 20127422  234 RKAMAGQRVELPCK---ALGHPepdyRWLKDNMPLELS-GRFQKTVTGLLIENIRPSDSGSYVCEvSNRYGTAKVI 305
Cdd:cd05872    6 RTVVAGADVVLPCQlrsNLASP----VWLFNGTPLNAQfSYLRLGTDGLLILVTSPEHSGTYRCY-SEEEGFQQLV 76

C-terminal immunoglobulin (Ig)-like domain of myotilin; member of the I-set of Ig superfamily (IgSF) domains; The members here are composed of the C-terminal immunoglobulin (Ig)-like domain of myotilin. Mytolin belongs to the palladin-myotilin-myopalladin family. Proteins belonging to the latter family contain multiple Ig-like domains and function as scaffolds, modulating the actin cytoskeleton. Myotilin is most abundant in skeletal and cardiac muscle and is involved in maintaining sarcomere integrity. It binds to alpha-actinin, filamin, and actin. Mutations in myotilin lead to muscle disorders. This group belongs to the I-set of IgSF domains, having A-B-E-D strands in one beta-sheet and A'-G-F-C-C' in the other. Like the V-set Ig domains, members of the I-set have a discontinuous A strand, but lack a C" strand.

Pssm-ID: 409473 Cd Length: 92 Bit Score: 37.44 E-value: 8.31e-03

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gi 20127422  690 PKFVVQPRDQDGIYGKAVILNCSAEGYPVPTIVWKfsKGAGVPQFQPialnGRIQVLSNGS----LLIKHVVEEDSGYYL 765
Cdd:cd05892    1 PMFIQKPQNKKVLEGDPVRLECQISAIPPPQIFWK--KNNEMLQYNT----DRISLYQDNCgricLLIQNANKKDAGWYT 74


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gi 20127422  766 CKVSNDVG 773
Cdd:cd05892   75 VSAVNEAG 82

First immunoglobulin variable (IgV) domain of poliovirus receptor (PVR, also known as CD155 and necl-5), and similar domains; The members here are composed of the first immunoglobulin (Ig) domain of poliovirus receptor (PVR, also known as CD155 and nectin-like protein 5 (necl-5)). Poliovirus (PV) binds to its cellular receptor (PVR/CD155) to initiate infection. CD155 is a membrane-anchored, single-span glycoprotein; its extracellular region has three Ig-like domains. There are four different isotypes of CD155 (referred to as alpha, beta, gamma, and delta), that result from alternate splicing of the CD155 mRNA, and have identical extracellular domains. CD155-beta and CD155-gamma are secreted; CD155-alpha and CD155-delta are membrane-bound and function as PV receptors. The virus recognition site is contained in the amino-terminal domain, D1. Having the virus attachment site on the receptor distal from the plasma membrane may be important for successful initiation of infection of cells by the virus. CD155 binds in the poliovirus "canyon" with a footprint similar to that of the intercellular adhesion molecule-1 receptor on human rhinoviruses. This group also includes the first Ig-like domain of nectin-1 (also known as poliovirus receptor related protein(PVRL)1; CD111), nectin-3 (also known as PVRL 3), nectin-4 (also known as PVRL4; LNIR receptor)and DNAX accessory molecule 1 (DNAM-1; CD226).

Pssm-ID: 409383 Cd Length: 113 Bit Score: 38.20 E-value: 8.65e-03

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gi 20127422  606 RFSIGQRVFIPCVV-VSGDLPIT-ITWQKDGRPIPGSL-------GVTIDN-----IDFTS--------SLRISNLSLMH 663
Cdd:cd05718   10 TGFLGGSVTLPCSLtSPGTTKITqVTWMKIGAGSSQNVavfhpqyGPSVPNpyaerVEFLAarlglrnaTLRIRNLRVED 89


                 ....*.
gi 20127422  664 NGNYTC 669
Cdd:cd05718   90 EGNYIC 95

Fourth immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM); The members here are composed of the fourth immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region, and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, and spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM.

Pssm-ID: 409453 [Multi-domain] Cd Length: 89 Bit Score: 37.18 E-value: 9.16e-03

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gi 20127422  697 RDQDGIY--GKAVILNCSAEGYPVPTIVWKFSkgaGVPqFQPIALNGRIQVlSNGSLLIKHVVEEDSGYYLCKVSNDVG 773
Cdd:cd05867    5 RPQSHLYgpGETARLDCQVEGIPTPNITWSIN---GAP-IEGTDPDPRRHV-SSGALILTDVQPSDTAVYQCEARNRHG 78

Immunoglobulin-like domain of human nephrin and similar proteins; member of the C1-set of Ig superfamily (IgSF) domains; The members here are composed of the immunoglobulin-like domain in human nephrin and similar proteins. Nephrin is an integral component of the slit diaphragm and is a central component of the glomerular ultrafilter. Nephrin plays a structural role and has a role in signaling. Nephrin is a transmembrane protein having a short intracellular portion, an extracellular portion comprised of eight Ig-like domains, and one fibronectin type III-like domain. The extracellular portions of nephrin from neighboring foot processes of separate podocyte cells may interact with each other, and in association with other components of the slit diaphragm form a porous molecular sieve within the slit pore. The intracellular portion of nephrin is associated with linker proteins, which connect nephrin to the actin cytoskeleton. The intracellular portion is tyrosine phosphorylated, and mediates signaling from the slit diaphragm into the podocytes.

Pssm-ID: 143250 Cd Length: 109 Bit Score: 37.99 E-value: 9.90e-03

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gi 20127422  809 CTAHGEKPIIVRWEKEDRIINPEMARYLVSTKEVGEEVISTLQILP-TVREDSGFFSCHAINSYGEDRGIIQLTVQEPPD 887
Cdd:cd05773   30 CQAQGVPRVQFRWAKNGVPLDLGNPRYEETTEHTGTVHTSILTIINvSAALDYALFTCTAHNSLGEDSLDIQLVSTSRPD 109

Third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM), and similar domains; The members here are composed of the third immunoglobulin (Ig)-like domain of the L1 cell adhesion molecule (CAM). L1 belongs to the L1 subfamily of cell adhesion molecules (CAMs) and is comprised of an extracellular region having six Ig-like domains and five fibronectin type III domains, a transmembrane region and an intracellular domain. L1 is primarily expressed in the nervous system and is involved in its development and function. L1 is associated with an X-linked recessive disorder, X-linked hydrocephalus, MASA syndrome, and spastic paraplegia type 1, that involves abnormalities of axonal growth. This group also contains the chicken neuron-glia cell adhesion molecule, Ng-CAM and human neurofascin.

Pssm-ID: 409394 [Multi-domain] Cd Length: 83 Bit Score: 37.00 E-value: 9.91e-03

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gi 20127422  414 SEKVVSPAEPVSLMCNVKGTPLPTITWTLDDDPILKGGshrisqmiTSEGNVVSYLNISSSQVRDGGVYRCTANNSAG 491
Cdd:cd05731    3 SSTMVLRGGVLLLECIAEGLPTPDIRWIKLGGELPKGR--------TKFENFNKTLKIENVSEADSGEYQCTASNTMG 72