Src Homology 3 domain of Membrane Protein, Palmitoylated 7 (or MAGUK p55 subfamily member 7); MPP7 is a scaffolding protein that binds to DLG1 and promotes tight junction formation and epithelial cell polarity. Mutations in the MPP7 gene may be associated with the pathogenesis of diabetes and extreme bone mineral density. It is one of seven vertebrate homologs of the Drosophila Stardust protein, which is required in establishing cell polarity, and it contains two L27 domains followed by the core of three domains characteristic of MAGUK (membrane-associated guanylate kinase) proteins: PDZ, SH3, and guanylate kinase (GuK). The GuK domain in MAGUK proteins is enzymatically inactive; instead, the domain mediates protein-protein interactions and associates intramolecularly with the SH3 domain. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1039756550 232 FIKALFDYDPKEDKAIPCKEAGLSFRKGDILQIMSQDDVTWWQAKHEGDANPRAGLIPSKH 292
Cdd:cd12033     1 FIKALFDYNPNEDKAIPCKEAGLSFKKGDILQIMSQDDATWWQAKHEGDANPRAGLIPSKH 61

domain in receptor targeting proteins Lin-2 and Lin-7;

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|..
gi 1039756550   75 LADDLTEELQNKL-PNSEIRELLKLLSKPNVKALLSVHDTVAQKSYDPVLPP 125
Cdd:smart00569   2 RLLELLEELQSLLsPSEDLQELRRLLQSPHLQALLKIHDKVAETELDPPLPE 53

Src Homology 3 domain of Membrane Protein, Palmitoylated 7 (or MAGUK p55 subfamily member 7); MPP7 is a scaffolding protein that binds to DLG1 and promotes tight junction formation and epithelial cell polarity. Mutations in the MPP7 gene may be associated with the pathogenesis of diabetes and extreme bone mineral density. It is one of seven vertebrate homologs of the Drosophila Stardust protein, which is required in establishing cell polarity, and it contains two L27 domains followed by the core of three domains characteristic of MAGUK (membrane-associated guanylate kinase) proteins: PDZ, SH3, and guanylate kinase (GuK). The GuK domain in MAGUK proteins is enzymatically inactive; instead, the domain mediates protein-protein interactions and associates intramolecularly with the SH3 domain. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1039756550 232 FIKALFDYDPKEDKAIPCKEAGLSFRKGDILQIMSQDDVTWWQAKHEGDANPRAGLIPSKH 292
Cdd:cd12033     1 FIKALFDYNPNEDKAIPCKEAGLSFKKGDILQIMSQDDATWWQAKHEGDANPRAGLIPSKH 61

domain in receptor targeting proteins Lin-2 and Lin-7;

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|...
gi 1039756550   16 ELLAALPAQLQPHVDSQEDLTFLWDVFGEKSLHSLVKIHEKLHCYEKQNPLPI 68
Cdd:smart00569   1 QRLLELLEELQSLLSPSEDLQELRRLLQSPHLQALLKIHDKVAETELDPPLPE 53

PDZ domain; PDZ domains are found in diverse signaling proteins.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1039756550 140 IRLVKNS-EPLGATIK--KDEQTGAITVARIMRGGAADRSGlIHVGDELREVNGIPVEDKRPEEIIKILSQSKGAITFKI 216
Cdd:pfam00595   2 VTLEKDGrGGLGFSLKggSDQGDPGIFVSEVLPGGAAEAGG-LKVGDRILSINGQDVENMTHEEAVLALKGSGGKVTLTI 80

                  .
gi 1039756550 217 I 217
Cdd:pfam00595  81 L 81

L27 domain; The L27 domain is found in receptor targeting proteins Lin-2 and Lin-7.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 1039756550  74 ALADDLTEELQNKL-PNSEIRELLKLLSKPNVKALLSVHDTVAQKSYDPVL 123
Cdd:pfam02828   2 ELVLELLEDLQPLSeASEDLAELQKLLQSPHLQALLEAHDKVAQKVYEPPS 52

C-terminal processing protease CtpA/Prc, contains a PDZ domain [Posttranslational modification, protein turnover, chaperones];

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1039756550 149 LGATIKKDEqtGAITVARIMRGGAADRSGlIHVGDELREVNGIPVEDKRPEEIIKILSQSKG-AITFKIIPSTKEET 224
Cdd:COG0793    62 LGAELGEED--GKVVVVSVIPGSPAEKAG-IKPGDIILAIDGKSVAGLTLDDAVKLLRGKAGtKVTLTIKRPGEGEP 135

Src Homology 3 domain of Membrane Protein, Palmitoylated 7 (or MAGUK p55 subfamily member 7); MPP7 is a scaffolding protein that binds to DLG1 and promotes tight junction formation and epithelial cell polarity. Mutations in the MPP7 gene may be associated with the pathogenesis of diabetes and extreme bone mineral density. It is one of seven vertebrate homologs of the Drosophila Stardust protein, which is required in establishing cell polarity, and it contains two L27 domains followed by the core of three domains characteristic of MAGUK (membrane-associated guanylate kinase) proteins: PDZ, SH3, and guanylate kinase (GuK). The GuK domain in MAGUK proteins is enzymatically inactive; instead, the domain mediates protein-protein interactions and associates intramolecularly with the SH3 domain. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1039756550 232 FIKALFDYDPKEDKAIPCKEAGLSFRKGDILQIMSQDDVTWWQAKHEGDANPRAGLIPSKH 292
Cdd:cd12033     1 FIKALFDYNPNEDKAIPCKEAGLSFKKGDILQIMSQDDATWWQAKHEGDANPRAGLIPSKH 61

PDZ domain of membrane palmitoylated proteins (MPPs), and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of MPP1-7 (also known as MAGUK p55 subfamily members 1-7), and related domains. MPPs comprise a subfamily of a larger group of multidomain proteins, namely, membrane-associated guanylate kinases (MAGUKs). MPPs form diverse protein complexes at the cell membranes, which are involved in a wide range of cellular processes, including establishing proper cell structure, polarity and cell adhesion. MPPs have only one PDZ domain. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This MPP1-like family domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1039756550 138 KIIRLVKN-SEPLGATIKKDEqtGAITVARIMRGGAADRSGLIHVGDELREVNGIPVEDKRPEEIIKILSQSKGAITFKI 216
Cdd:cd06726     1 RLVEFEKArDEPLGATIKMEE--DSVIVARILHGGMAHRSGLLHVGDEILEINGIPVSGKTVDELQKLLSSLSGSVTFKL 78

                  ..
gi 1039756550 217 IP 218
Cdd:cd06726    79 IP 80

Src Homology 3 domain of Membrane Protein, Palmitoylated 1 (or MAGUK p55 subfamily member 1)-like proteins; This subfamily includes MPP1, CASK (Calcium/calmodulin-dependent Serine protein Kinase), Caenorhabditis elegans lin-2, and similar proteins. MPP1 and CASK are scaffolding proteins from the MAGUK (membrane-associated guanylate kinase) protein family, which is characterized by the presence of a core of three domains: PDZ, SH3, and guanylate kinase (GuK). In addition, they also have the Hook (Protein 4.1 Binding) motif in between the SH3 and GuK domains. The GuK domain in MAGUK proteins is enzymatically inactive; instead, the domain mediates protein-protein interactions and associates intramolecularly with the SH3 domain. CASK and lin-2 also contain an N-terminal calmodulin-dependent kinase (CaMK)-like domain and two L27 domains. MPP1 is ubiquitously-expressed and plays roles in regulating neutrophil polarity, cell shape, hair cell development, and neural development and patterning of the retina. CASK is highly expressed in the mammalian nervous system and plays roles in synaptic protein targeting, neural development, and gene expression regulation. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*....
gi 1039756550 232 FIKALFDYDPKEDKAIPCKEAGLSFRKGDILQIMSQDDVTWWQAKHEGDANPRAGLIPS 290
Cdd:cd12035     1 YVRAQFDYDPSKDDLIPCQQAGIAFKTGDILQIISKDDHNWWQARKPGASKEPAGLIPS 59

PDZ domain of membrane palmitoylated protein 5 (MPP5), Drosophila Stardust, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of MPP5, Drosophila Stardust, and related domains. MPP5 (also known as MAGUK p55 subfamily member 1, protein associated with Lin-7 1 or PALS1) and Drosophila Stardust are membrane-associated guanylate kinase (MAGUK)-like proteins that serve as signaling and scaffolding proteins, linking different proteins critical to the formation and maintenance of tight junctions (TJ) and apical-basal polarity. Apical-basal polarity determinants cluster in complexes; in particular, the Crumbs complex (Crb, MPP5, and PATJ) and the PAR/aPKC-complex (PAR-3, PAR-6, aPKC) determine the apical plasma membrane domain. Within the Crumbs complex, Crb is stabilized in the plasma membrane by MPP5, which in turn recruits PATJ and Lin-7 to the complex. MPP5 also links the Crumbs complex with the PAR/aPKC-complex. The Drosophila homolog of the Crumbs complex is the (CRB)-Stardust (Sdt)-Discs Lost (Dlt) complex. MPP5 also acts as an interaction partner for SARS-CoV envelope protein E, which results in delayed formation of TJs and dysregulation of cell polarity. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This MPP5-like family domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1039756550 138 KIIRLVKNSEPLGATIKKDEqtGAITVARIMRGGAADRSGLIHVGDELREVNGIPVEDKRPEEIIKILSQSKGAITFKII 217
Cdd:cd06798     1 KIVRIEKTREPLGATVRNEG--DSVIISRIVKGGAAEKSGLLHEGDEILEINGIEIRGKDVNEVCDLLADMHGTLTFLLI 78

                  .
gi 1039756550 218 P 218
Cdd:cd06798    79 P 79

PDZ domain of peripheral plasma membrane protein CASK, Caenorhabditis Lin-2, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of CASK, Caenorhabditis elegans Lin-2, and related domains. CASK and Lin-2 are membrane-associated guanylate kinase (MAGUK)-like proteins. CASK (also known as Calcium/calmodulin-dependent protein kinase, CAKI, and Camguk) has a role in synaptic transmembrane protein anchoring and ion channel trafficking. CASK may regulate transmembrane proteins that bind calcium, calmodulin, or nucleotides; it regulates the Drosophila ether a go-go (eag) potassium channel, and also regulates autophosphorylation of CaMKII. CASK binding partners include the transcription factor TBR1, and cell-surface proteins, including amyloid precursor protein, neurexins, and syndecans. Lin-2, as a component of the CLin-10-Lin-2-Lin-7 complex, plays a role in controlling the basolateral localization of the EGF receptor Let-23; this complex also associates with the neuron-specific motor protein KIF17 to transport vesicles containing N-methyl-D-aspartate (NMDA) receptor 2B along microtubules. CASK may also function in targeting or scaffolding of the protein parkin which is selectively truncated by a Parkinson's disease-causing mutation; the C-terminus of parkin functions as a class II PDZ-binding motif that binds CASK. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This MPP6-MPP2-like family domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1039756550 138 KIIRLVKNS-EPLGATIKKDEQtGAITVARIMRGGAADRSGLIHVGDELREVNGIPVEDKRPEEIIKILSQSKGAITFKI 216
Cdd:cd10831     1 RLVQFQKNTdEPMGITLKMNED-GRCIVARIMHGGMIHRQGTLHVGDEIREINGISVANQTVEQLQKMLREARGSITFKI 79

                  ..
gi 1039756550 217 IP 218
Cdd:cd10831    80 VP 81

Src Homology 3 domain of Calcium/calmodulin-dependent Serine protein Kinase; CASK is a scaffolding protein that is highly expressed in the mammalian nervous system and plays roles in synaptic protein targeting, neural development, and gene expression regulation. CASK interacts with many different binding partners including parkin, neurexin, syndecans, calcium channel proteins, caskin, among others, to perform specific functions in different subcellular locations. Disruption of the CASK gene in mice results in neonatal lethality while mutations in the human gene have been associated with X-linked mental retardation. Drosophila CASK is associated with both pre- and postsynaptic membranes and is crucial in synaptic transmission and vesicle cycling. CASK contains an N-terminal calmodulin-dependent kinase (CaMK)-like domain, two L27 domains, followed by the core of three domains characteristic of MAGUK (membrane-associated guanylate kinase) proteins: PDZ, SH3, and guanylate kinase (GuK). In addition, it also contains the Hook (Protein 4.1 Binding) motif in between the SH3 and GuK domains. The GuK domain in MAGUK proteins is enzymatically inactive; instead, the domain mediates protein-protein interactions and associates intramolecularly with the SH3 domain. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*....
gi 1039756550 232 FIKALFDYDPKEDKAIPCKEAGLSFRKGDILQIMSQDDVTWWQAKHEGDANPRAGLIPS 290
Cdd:cd12081     1 YVRAQFEYDPLKDDLIPCKQAGIRFRVGDILQIISKDDHNWWQAKLENSKNGTAGLIPS 59

Src Homology 3 domain of Membrane Protein, Palmitoylated 4 (or MAGUK p55 subfamily member 4); MPP4, also called Disks Large homolog 6 (DLG6) or Amyotrophic lateral sclerosis 2 chromosomal region candidate gene 5 protein (ALS2CR5), is a retina-specific scaffolding protein that plays a role in organizing presynaptic protein complexes in the photoreceptor synapse, where it localizes to the plasma membrane. It is required in the proper localization of calcium ATPases and for maintenance of calcium homeostasis. MPP4 is one of seven vertebrate homologs of the Drosophila Stardust protein, which is required in establishing cell polarity, and it contains two L27 domains followed by the core of three domains characteristic of MAGUK (membrane-associated guanylate kinase) proteins: PDZ, SH3, and guanylate kinase (GuK). The GuK domain in MAGUK proteins is enzymatically inactive; instead, the domain mediates protein-protein interactions and associates intramolecularly with the SH3 domain. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1039756550 232 FIKALFDYDPKEDKAIPCKEAGLSFRKGDILQIMSQDDVTWWQAKHEGDANPRAGLIPSKH 292
Cdd:cd12034     1 YVRAMVDYWPQQDPSIPCADAGLPFRKGDILQIVDQNDSLWWQARKLSDLAACAGLIPSNH 61

canonical PDZ domain; Canonical PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain. PDZ domains usually bind to short specific peptide sequences located at the C-terminal end of their partner proteins known as PDZ binding motifs. These domains can also interact with internal peptide motifs and certain lipids, and can take part in a head-to-tail oligomerization with other PDZ domains. The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. The canonical PDZ domain contains six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1039756550 140 IRLVKNS-EPLGATIK--KDEQTGaITVARIMRGGAADRSGLIHVGDELREVNGIPVEDKRPEEIIKILSQSKGAITFKI 216
Cdd:cd00136     2 VTLEKDPgGGLGFSIRggKDGGGG-IFVSRVEPGGPAARDGRLRVGDRILEVNGVSLEGLTHEEAVELLKSAGGEVTLTV 80

Src Homology 3 domain of Disks large homolog proteins; The DLG-like proteins are scaffolding proteins that cluster at synapses and are also called PSD (postsynaptic density)-95 proteins or SAPs (synapse-associated proteins). They play important roles in synaptic development and plasticity, cell polarity, migration and proliferation. They are members of the MAGUK (membrane-associated guanylate kinase) protein family, which is characterized by the presence of a core of three domains: PDZ, SH3, and guanylate kinase (GuK). The GuK domain in MAGUK proteins is enzymatically inactive; instead, the domain mediates protein-protein interactions and associates intramolecularly with the SH3 domain. DLG-like proteins contain three PDZ domains and varying N-terminal regions. All DLG proteins exist as alternatively-spliced isoforms. Vertebrates contain four DLG proteins from different genes, called DLG1-4. DLG4 and DLG2 are found predominantly at postsynaptic sites and they mediate surface ion channel and receptor clustering. DLG3 is found axons and some presynaptic terminals. DLG1 interacts with AMPA-type glutamate receptors and is critical in their maturation and delivery to synapses. The SH3 domain of DLG4 binds and clusters the kainate subgroup of glutamate receptors via two proline-rich sequences in their C-terminal tail. It also binds AKAP79/150 (A-kinase anchoring protein). SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1039756550 232 FIKALFDYDPKEDKAIPCKeaGLSFRKGDILQIMSQDDVTWWQAKHEGDAN--PRAGLIPSK 291
Cdd:cd11861     1 YVRALFDYDPSRDSGLPSQ--GLSFKFGDILHVTNASDDEWWQARRVTPNGeeEEVGVIPSK 60

domain in receptor targeting proteins Lin-2 and Lin-7;

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|...
gi 1039756550   16 ELLAALPAQLQPHVDSQEDLTFLWDVFGEKSLHSLVKIHEKLHCYEKQNPLPI 68
Cdd:smart00569   1 QRLLELLEELQSLLSPSEDLQELRRLLQSPHLQALLKIHDKVAETELDPPLPE 53

Src Homology 3 domain of Disks Large homolog 2; DLG2, also called postsynaptic density-93 (PSD93) or Channel-associated protein of synapse-110 (chapsyn 110), is a scaffolding protein that clusters at synapses and plays an important role in synaptic development and plasticity. The DLG2 delta isoform binds inwardly rectifying potassium Kir2 channels, which determine resting membrane potential in neurons. It regulates the spatial and temporal distribution of Kir2 channels within neuronal membranes. DLG2 is a member of the MAGUK (membrane-associated guanylate kinase) protein family, which is characterized by the presence of a core of three domains: PDZ, SH3, and guanylate kinase (GuK). The GuK domain in MAGUK proteins is enzymatically inactive; instead, the domain mediates protein-protein interactions and associates intramolecularly with the SH3 domain. DLG2 contains three PDZ domains. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 1039756550 231 IFIKALFDYDPKEDKAIPCKeaGLSFRKGDILQIMSQDDVTWWQAKH---EGDANpRAGLIPSKHFQER 296
Cdd:cd12032     6 LYVRAMFDYEKSKDSGLPSQ--GLSFRYGDILHVINASDDEWWQARRvtpDGDSE-EMGVIPSKRRVER 71

PDZ domain 6 of glutamate receptor-interacting protein 1 (GRIP1) and GRIP2, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) binding proteins GRIP1 (ABP/GRIP2) and GRIP2, and related domains. GRIP1 and GRIP2 each have 7 PDZ domains. The interaction of GRIP1 and GRIP2 with GluA2/3 (AMPAR subunit) regulates AMPAR trafficking and synaptic targeting. GRIP1 has an essential role in regulating AMPAR trafficking during synaptic plasticity and learning and memory. GRIP1 and GRIP2 interact with a variety of other proteins associated with protein trafficking and internalization, for example GRIP1 also interacts with KIF5 (also known as kinesin 1), EphB receptors, scaffold protein liprin-alpha, and the rasGEF GRASP-1. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This GRIP family PDZ6 domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1039756550 140 IRLVKNSEPLGATIKKDEQTG-AITVARIMRGGAADRSGLIHVGDELREVNGIPVEDKRPEEIIKILSQSKGAITFKI 216
Cdd:cd06683     6 VELKRYGGPLGITISGTEEPFdPIVISGLTEGGLAERTGAIHVGDRILAINGESLRGKPLSEAIHLLQNAGDTVTLKI 83

L27 domain; The L27 domain is found in receptor targeting proteins Lin-2 and Lin-7.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 1039756550  74 ALADDLTEELQNKL-PNSEIRELLKLLSKPNVKALLSVHDTVAQKSYDPVL 123
Cdd:pfam02828   2 ELVLELLEDLQPLSeASEDLAELQKLLQSPHLQALLEAHDKVAQKVYEPPS 52

C-terminal Src homology 3 domain of Growth factor receptor-bound protein 2; GRB2 is a critical signaling molecule that regulates the Ras pathway by linking tyrosine kinases to the Ras guanine nucleotide releasing protein Sos (son of sevenless), which converts Ras to the active GTP-bound state. It is ubiquitously expressed in all tissues throughout development and is important in cell cycle progression, motility, morphogenesis, and angiogenesis. In lymphocytes, GRB2 is associated with antigen receptor signaling components. GRB2 contains an N-terminal SH3 domain, a central SH2 domain, and a C-terminal SH3 domain. The C-terminal SH3 domain of GRB2 binds to Gab2 (Grb2-associated binder 2) through epitopes containing RxxK motifs, as well as to the proline-rich C-terminus of FGRF2. SH3 domains are protein interaction domains that typically bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1039756550 232 FIKALFDYDPKEDKAipckeagLSFRKGDILQIMSQDDVTWWQakheGDANPRAGLIPSKHFQ 294
Cdd:cd11949     1 YVQALFDFDPQEDGE-------LGFRRGDFIEVMDNSDPNWWK----GACHGQTGMFPRNYVT 52

PDZ domain of partitioning defective 6 (Par6), Drosophila Rho GTPase-activating protein 100F (RhoGAP100F), and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of Par6 (also known as PAR6 or Par-6), RhoGAP100F, and related domains. Par6 is part of a conserved machinery that directs metazoan cell polarity, a process necessary for the function of diverse cell types. Par6 forms a cell polarity-regulatory complex with atypical protein kinase C (aPKC) and Par3. Par6 can also directly associate with PALS1 (proteins associated with Lin7, also known as Stardust) providing a link between the Par3/aPKC/Par6 complex and the PALS1-PATJ (protein-associated TJ) complex. Binding partners of the Par6-PDZ domain include Par3, PALS1/Stardust; leucine-rich repeat-containing protein netrin-G ligand-2 (NGL-2), human crumbs (CRB3) involve in the morphogenesis of the tight junctions in mammalian epithelial cells, and PAR-6 co-operates with the Par6 semi-CRIB domain to bind CDC42. CDC42 regulates the Par6 PDZ domain through an allosteric CRIB-PDZ transition. Drosophila RhoGAP100F, also known as synapse defective protein 1 homolog (syd-1 homolog), is a GTPase activator for the Rho-type GTPases by converting them to an inactive GDP-bound form. The RhoGAP100F-PDZ domain binds the neurexin C terminus to control synapse formation at the Drosophila neuromuscular junction. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This Par6-like family domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1039756550 138 KIIRLVK-NSEPLGATIKKD---EQTGAITVARIMRGGAADRSGLIHVGDELREVNGIPVEDKRPEEIIKILS 206
Cdd:cd06718     1 RRVELIKpPGKPLGFYIRDGngvERVPGIFISRLVLGSLADSTGLLAVGDEILEVNGVEVTGKSLDDVTDMMV 73

Src Homology 3 domain of Disks Large homolog 3; DLG3, also called synapse-associated protein 102 (SAP102), is a scaffolding protein that clusters at synapses and plays an important role in synaptic development and plasticity. Mutations in DLG3 cause midgestational embryonic lethality in mice and may be associated with nonsyndromic X-linked mental retardation in humans. It interacts with the NEDD4 (neural precursor cell-expressed developmentally downregulated 4) family of ubiquitin ligases and promotes apical tight junction formation. DLG3 is a member of the MAGUK (membrane-associated guanylate kinase) protein family, which is characterized by the presence of a core of three domains: PDZ, SH3, and guanylate kinase (GuK). The GuK domain in MAGUK proteins is enzymatically inactive; instead, the domain mediates protein-protein interactions and associates intramolecularly with the SH3 domain. DLG3 contains three PDZ domains. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 1039756550 231 IFIKALFDYDPKEDKAIPCKeaGLSFRKGDILQIMSQDDVTWWQAK---HEGDANpRAGLIPSK 291
Cdd:cd12029     3 LYVRALFDYDRTRDSCLPSQ--GLSFSYGDILHVINASDDEWWQARlvtPHGESE-QIGVIPSK 63

PDZ domain of Golgi-associated PDZ and coiled-coil motif-containing protein (GOPC), and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of GOPC and related domains. GOPC, also known as PIST (PDZ domain protein interacting specifically with TC10), FIG (fused in glioblastoma), and CAL (CFTR-associated ligand), regulates the trafficking of a wide array of proteins, including small GTPases, receptors, and cell surface molecules such as cadherin 23 and CFTR. It may regulate CFTR chloride currents and acid-sensing ASIC3 currents by modulating cell surface expression of both channels, and may play a role in autophagy. Interaction partners of the GOPC PDZ domains include: FZD5, FZD8, ASIC3, CFTR, MUC3, ARFRP1, Ggamma13, neuroligin, and Stargazin. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This GOPC-like family domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1039756550 140 IRLVKN-SEPLGATIKKDEQTGA-ITVARIMRGGAADRSGLIHVGDELREVNGIPVEDKRPEEIIKILSQSKGAITFKII 217
Cdd:cd06800     3 VLLSKEpHEGLGISITGGKEHGVpILISEIHEGQPADRCGGLYVGDAILSVNGIDLRDAKHKEAVTILSQQRGEITLEVV 82

Src Homology 3 domain of metazoan osteoclast stimulating factor 1; OSTF1, also named OSF or SH3P2, is a signaling protein containing SH3 and ankyrin-repeat domains. It acts through a Src-related pathway to enhance the formation of osteoclasts and bone resorption. It also acts as a negative regulator of cell motility. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 1039756550 232 FIKALFDYDPKEDKAipckeagLSFRKGDILQIMSQDDVTWWQAKHEGdanpRAGLIPSKHFQE 295
Cdd:cd11772     1 VFRALYDYEAQHPDE-------LSFEEGDLLYISDKSDPNWWKATCGG----KTGLIPSNYVEE 53

PDZ domain 4 of membrane-associated guanylate kinase inverted 1 (MAGI-1), MAGI-2, and MAGI-3, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 4 of MAGI1, 2, 3 (MAGI is also known as Membrane-associated guanylate kinase, WW and PDZ domain-containing protein) and related domains. MAGI proteins have been implicated in the control of cell migration and invasion through altering the activity of phosphatase and tensin homolog (PTEN) and modulating Akt signaling. Four MAGI proteins have been identified (MAGI1-3 and MAGIX). MAGI1-3 have 6 PDZ domains and bind to the C-terminus of PTEN via their PDZ2 domain. MAGIX has a single PDZ domain that is related to MAGI1-3 PDZ domain 5. Other binding partners for MAGI1 include JAM4, C-terminal tail of high risk HPV-18 E6, megalin, TRAF6, Kir4.1 (basolateral K+ channel subunit), and cadherin 23; for MAGI2, include DASM1, dendrin, axin, beta- and delta-catenin, neuroligin, hyperpolarization-activated cation channels, beta1-adrenergic receptors, NMDA receptor, and TARPs; and for MAGI3 includes LPA2. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This MAGI family PDZ4 domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2); arranged as beta-strands A, -B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

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                  ....*....|....*....|....*....|....*....|....*....|....*.
gi 1039756550 163 TVARIMRGGAADRSGLIHVGDELREVNGIPVEDKRPEEIIKILSQSKGAITFKIIP 218
Cdd:cd06734    29 KIGRIIPGSPADRCGQLKVGDRILAVNGISILNLSHGDIVNLIKDSGLSVTLTIVP 84

Src homology 3 domain of Src kinase-like Protein Tyrosine Kinases; Src subfamily members include Src, Lck, Hck, Blk, Lyn, Fgr, Fyn, Yrk, Yes, and Brk. Src (or c-Src) proteins are cytoplasmic (or non-receptor) PTKs which are anchored to the plasma membrane. They contain an N-terminal SH4 domain with a myristoylation site, followed by SH3 and SH2 domains, a tyr kinase domain, and a regulatory C-terminal region containing a conserved tyr. They are activated by autophosphorylation at the tyr kinase domain, but are negatively regulated by phosphorylation at the C-terminal tyr by Csk (C-terminal Src Kinase). However, Brk lacks the N-terminal myristoylation sites. Src proteins are involved in signaling pathways that regulate cytokine and growth factor responses, cytoskeleton dynamics, cell proliferation, survival, and differentiation. They were identified as the first proto-oncogene products, and they regulate cell adhesion, invasion, and motility in cancer cells, and tumor vasculature, contributing to cancer progression and metastasis. Src kinases are overexpressed in a variety of human cancers, making them attractive targets for therapy. They are also implicated in acute inflammatory responses and osteoclast function. Src, Fyn, Yes, and Yrk are widely expressed, while Blk, Lck, Hck, Fgr, Lyn, and Brk show a limited expression pattern. This subfamily also includes Drosophila Src42A, Src oncogene at 42A (also known as Dsrc41) which accumulates at sites of cell-cell or cell-matrix adhesion, and participates in Drosphila development and wound healing. It has been shown to promote tube elongation in the tracheal system, is essential for proper cell-cell matching during dorsal closure, and regulates cell-cell contacts in developing Drosophila eyes. The SH3 domain of Src kinases contributes to substrate recruitment by binding adaptor proteins/substrates, and regulation of kinase activity through an intramolecular interaction. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

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                  ....*....|....*....|....*....|....*....|....*....|....*...
gi 1039756550 235 ALFDYDP--KEDkaipckeagLSFRKGDILQIMSQDDVTWWQAKHEgdANPRAGLIPS 290
Cdd:cd11845     4 ALYDYEArtDDD---------LSFKKGDRLQILDDSDGDWWLARHL--STGKEGYIPS 50

PDZ domain 3 of Discs Large 5 (Dlg5) and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 3 of Drosophila and mammalian Dlg5, and related domains. Dlg5 is a scaffold protein with multiple conserved functions that are independent of each other in regulating growth, cell polarity, and cell adhesion. It has a coiled-coil domain, 4 PDZ domains and a MAGUK domain (an SH3 domain next to a non-catalytically active guanylate kinase domain). Deregulation of Dlg5 has been implicated in the malignancy of several cancer types. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This Dlg5-like family PDZ3 domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1039756550 140 IRLVKNSEPLGATIKKDEQtGAITVARIMRGGAADRSGLiHVGDELREVNGIPVEDKRPEEIIKILSQSKGAITFKI 216
Cdd:cd06767     6 VSIEKGSEPLGISIVSGEN-GGIFVSSVTEGSLAHQAGL-EYGDQLLEVNGINLRNATEQQAALILRQCGDTITMLV 80

circularly permuted PDZ domain of C-terminal processing peptidase (CPP), a serine protease, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of CPP (also known as tail-specific protease, PRC protein, Protease Re, and Photosystem II D1 protein processing peptidase), and related domains. CPP belongs to the peptidase S41A family. It cleaves a C-terminal 11 residue peptide from the precursor form of penicillin-binding protein 3, and may have a role in protecting bacterium from thermal and osmotic stresses. In the plant chloroplast, the enzyme removes the C-terminal extension of the D1 polypeptide of photosystem II. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains and as well as those with circular permutations and domain swapping of beta-strands. The canonical PDZ domain contains six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2); arranged as A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F. This CPP-like PDZ domain is a circularly permuted PDZ domain which places beta-strand A on the C-terminus. Another permutation exists in the PDZ superfamily which places both beta-strands A and B on the C-terminus.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 1039756550 149 LGATIKKDEQtGAITVARIMRGGAADRSGlIHVGDELREVNGIPVEDKRPEEIIKILSQSKG-AITFKIIPSTKEET 224
Cdd:cd06782     4 IGIEIGKDDD-GYLVVVSPIPGGPAEKAG-IKPGDVIVAVDGESVRGMSLDEVVKLLRGPKGtKVKLTIRRGGEGEP 78

PDZ domain 8 of multi-PDZ-domain protein 1 (MUPP1), PDZ domain 7 of protein-associated tight junction (PATJ), PDZ domain 2 of Drosophila melanogaster inactivation-no-after-potential D (INAD), and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 8 of MUPP1, PDZ domain 7 of PATJ, and PDZ domain 2 of Drosophila melanogaster INAD, and related domains. MUPP1 and PATJ serve as scaffolding proteins linking different proteins and protein complexes involved in the organization of tight junctions and epithelial polarity. MUPP1 contains an L27 (Lin-2 and Lin-7 binding) domain and 13 PDZ domains. PATJ (also known as INAD-like) contains an L27 domain and ten PDZ domains. MUPP1 and PATJ share several binding partners, including junctional adhesion molecules (JAM), zonula occludens (ZO)-3, Pals1 (protein associated with Lin-7), Par (partitioning defective)-6 proteins, and nectins (adherence junction adhesion molecules). PATJ lacks 3 PDZ domains seen in MUPP1: PDZ6, 9, and 13; consequently, MUPP1 PDZ7 and 8 align with PATJ PDZ6 and 7; and MUPP1 PDZ domains 10-12 align with PATJ PDZ domains 8-10. INAD assembles key enzymes of the Drosophila compound eye photo-transduction pathway into a supramolecular complex, supporting efficient and fast light signaling. It contains 5 PDZ domains arranged in tandem (PDZ1-PDZ5) which independently bind various proteins. INAD PDZ2 binds eye-specific protein kinase C. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This MUPP1-like family PDZ8 domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

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                  ....*....|....*....|....*....|....*....|....*....|....*..
gi 1039756550 139 IIRLVKNSEPLGATI--KKDEQTGAITVARIMRGGAADRSGLIHVGDELREVNGIPV 193
Cdd:cd06672     3 LIELEKGSSGLGLSLagNKDRSRMSVFVVGIDPDGAAGKDGRIQVGDELLEINGQVL 59

PDZ domain 6 of multi-PDZ-domain protein 1 (MUPP1) and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 6 of multi-PDZ-domain protein 1 (MUPP1). MUPP1 and PATJ serve as scaffolding proteins linking different proteins and protein complexes involved in the organization of tight junctions and epithelial polarity. MUPP1 contains an L27 (Lin-2 and Lin-7 binding) domain and 13 PDZ domains. PATJ (also known as INAD-like) contains an L27 domain and ten PDZ domains. PATJ lacks 3 PDZ domains seen in MUPP1: PDZ6, PDZ9, and PDZ13. This MuPP1-like PDZ6 domain is therefore absent from PATJ. MUPP1 and PATJ share several binding partners, including junctional adhesion molecules (JAM), zonula occludens (ZO)-3, Pals1 (protein associated with Lin-7), Par (partitioning defective)-6 proteins, and nectins (adherence junction adhesion molecules). PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This MUPP1-like family PDZ6 domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F

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                  ....*....|....*....|....*....|....*....|....*....|....*..
gi 1039756550 137 VKIIRLVKNSEPLGATIKKDEQTGAITVARIMRGGAADRSGLIHVGDELREVNGIPV 193
Cdd:cd06670     4 ERTITIVKGNSSLGITVSADKDGNGCIVKSIIHGGAVSRDGRISVGDFIVSINNESL 60

PDZ domain 1 of harmonin isoforms a, b, and c, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 1 of harmonin isoforms a, b, and c, and related domains. Harmonin (also known as Usher Type 1C, PDZ-73 and AIE-75) is a key organizer of the Usher (USH) protein interactome. USH syndrome is the leading cause of hereditary sensory deaf-blindness in humans; three clinically distinct types of USH have been identified, type 1 to 3. The gene encoding harmonin (USH1C) is the causative gene for the USH type 1C phenotype. There are at least 10 alternatively spliced isoforms of harmonin, which are divided into three subclasses (a, b, and c). All isoforms contain the first two PDZ domains and the first coiled-coil domain. The a and b isoforms all have a third PDZ domain. The different PDZ domains are responsible for interactions with all known Usher syndrome type 1 proteins, and most Usher syndrome type 2 proteins. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This harmonin family PDZ1 domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1039756550 137 VKIIRLVKNS-EPLGATIKKDEQTG-AITVARIMRGGAADRSGLiHVGDELREVNGIPVEDKRPEEIIKiLSQSKGAITF 214
Cdd:cd06737     2 LRLVRLDRRGpESLGFSVRGGLEHGcGLFVSHVSPGSQADNKGL-RVGDEIVRINGYSISQCTHEEVIN-LIKTKKTVSL 79

                  ..
gi 1039756550 215 KI 216
Cdd:cd06737    80 KV 81

PDZ domain 3 of multi-PDZ-domain protein 1 (MUPP1) and PATJ (protein-associated tight junction) and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 3 of MUPP1 and PATJ, and related domains. MUPP1 and PATJ serve as scaffolding proteins linking different proteins and protein complexes involved in the organization of tight junctions and epithelial polarity. MUPP1 contains an L27 (Lin-2 and Lin-7 binding) domain and 13 PDZ domains. PATJ (also known as INAD-like) contains an L27 domain and ten PDZ domains. MUPP1 and PATJ share several binding partners, including junctional adhesion molecules (JAM), zonula occludens (ZO)-3, Pals1 (protein associated with Lin-7), Par (partitioning defective)-6 proteins, and nectins (adherence junction adhesion molecules). PATJ lacks 3 PDZ domains seen in MUPP1: PDZ6, 9, and 13; consequently, MUPP1 PDZ7 and 8 align with PATJ PDZ6 and 7; and MUPP1 PDZ domains 10-12 align with PATJ PDZ domains 8-10. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This MUPP1-like family domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

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gi 1039756550 140 IRLVKNSEPLGATI-------KKDEQTGaITVARIMRGGAADRSGLIHVGDELREVNGIPVEDKRPEEIIKILSQS 208
Cdd:cd06791     5 VELVKDEQGLGITIagyvgekASGELSG-IFVKSIIPGSAADQDGRIQVNDQIIAVDGVNLQGFTNQEAVEVLRNT 79

PDZ domain of segment polarity protein dishevelled homolog DVL1, DVL2, DVL3, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of DVL1-3, and related domains. The dishevelleds (DVL1, 2 and 3 in humans) act downstream of Frizzled (FZD) receptors in both the canonical and non-canonical WNT signaling pathway; they bind the cytoplasmic C-terminus of frizzled family members and transduce the Wnt signal to down-stream effectors. They bind to several proteins known to modulate Wnt signaling. Binding partners of the DVL1 PDZ domain include nucleoredoxin (NXN), Van Gogh-like (VANGL1), Wnt receptor RYK, Dapper 1 (DACT1), Frizzled7 (FZD7), transmembrane protein 88 (TMEM88), Daple (dishevelled-associating protein with a high frequency of leucines), also known as Ccdc88c), and cysteine-rich protein Idax. The DVL2 PDZ domain has been shown to bind the nuclear export signal sequence of the DVL2 protein. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This DVL-like family domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 1039756550 144 KNSEPLGATI---KKDEQTGAITVARIMRGGAADRSGLIHVGDELREVNGIPVEDKRPEEIIKIL---SQSKGAITFKI 216
Cdd:cd06717     7 EKVNFLGISIvgqSNERGDGGIYVGSIMKGGAVAADGRIEPGDMILQVNDISFENMSNDDAVRVLreaVHKPGPITLTV 85

C-terminal Src homology 3 domain of Growth factor receptor-bound protein 2 (GRB2) and related proteins; This family includes the adaptor protein GRB2 and related proteins including Drosophila melanogaster Downstream of receptor kinase (DRK), Caenorhabditis elegans Sex muscle abnormal protein 5 (Sem-5), GRB2-related adaptor protein (GRAP), GRAP2, and similar proteins. Family members contain an N-terminal SH3 domain, a central SH2 domain, and a C-terminal SH3 domain. GRB2/Sem-5/DRK is a critical signaling molecule that regulates the Ras pathway by linking tyrosine kinases to the Ras guanine nucleotide releasing protein Sos (son of sevenless), which converts Ras to the active GTP-bound state. GRAP2 plays an important role in T cell receptor (TCR) signaling by promoting the formation of the SLP-76:LAT complex, which couples the TCR to the Ras pathway. GRAP acts as a negative regulator of T cell receptor (TCR)-induced lymphocyte proliferation by downregulating the signaling to the Ras/ERK pathway. The C-terminal SH3 domains (SH3c) of GRB2 and GRAP2 have been shown to bind to classical PxxP motif ligands, as well as to non-classical motifs. GRB2 SH3c binds Gab2 (Grb2-associated binder 2) through epitopes containing RxxK motifs, while the SH3c of GRAP2 binds to the phosphatase-like protein HD-PTP via a RxxxxK motif. SH3 domains are protein interaction domains that typically bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 1039756550 232 FIKALFDYDPKEdkaipckEAGLSFRKGDILQIMSQDDVTWWqakhEGDANPRAGLIPSKHFQE 295
Cdd:cd11805     1 RVQALYDFNPQE-------PGELEFRRGDIITVLDSSDPDWW----KGELRGRVGIFPANYVQP 53

SH3 domain; SH3 (Src homology 3) domains are often indicative of a protein involved in signal transduction related to cytoskeletal organization. First described in the Src cytoplasmic tyrosine kinase. The structure is a partly opened beta barrel.

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gi 1039756550 234 KALFDYDPKEDKaipckEagLSFRKGDILQIMSQDDVTWWQAKHEGDanpRAGLIPS 290
Cdd:pfam00018   1 VALYDYTAQEPD-----E--LSFKKGDIIIVLEKSEDGWWKGRNKGG---KEGLIPS 47

PDZ domain 2 of PDZ domain containing 2 (PDZD2), and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 2 of PDZD2, also known as KIAA0300, PIN-1, activated in prostate cancer (AIPC) and PDZ domain-containing protein 3 (PDZK3). PDZD2 has seven PDZ domains, and is expressed at exceptionally high levels in the pancreas and certain cancer tissues such as prostate cancer. It promotes the proliferation of insulinoma cells and is upregulated during prostate tumorigenesis. In osteosarcoma (OS), the microRNA miR-363 acts as a tumor suppressor by inhibiting PDZD2. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This PDZD2-like family PDZ2 domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1039756550 136 SVKIIRLVKNSEPLGATIK--KDEQTG--AITVARIMRGGAADRSGLIHVGDELREVNGIPVEDKRPEEIIKILSQSKGA 211
Cdd:cd06758     1 RVWKMHLLKEKGGLGIQITggKGSKRGdiGIFVAGVEEGGSADRDGRLKKGDELLMINGQSLIGLSHQEAVAILRSSASP 80

                  .
gi 1039756550 212 I 212
Cdd:cd06758    81 V 81

Third Src homology 3 domain of Rab3-interacting molecules (RIMs) binding proteins; RIMs binding proteins (RBPs, RIM-BPs) associate with calcium channels present in photoreceptors, neurons, and hair cells; they interact simultaneously with specific calcium channel subunits, and active zone proteins, RIM1 and RIM2. RIMs are part of the matrix at the presynaptic active zone and are associated with synaptic vesicles through their interaction with the small GTPase Rab3. RIM-BPs play a role in regulating synaptic transmission by serving as adaptors and linking calcium channels with the synaptic vesicle release machinery. RIM-BPs contain three SH3 domains and two to three fibronectin III repeats. Invertebrates contain one, while vertebrates contain at least two RIM-BPs, RIM-BP1 and RIM-BP2. RIM-BP1 is also called peripheral-type benzodiazapine receptor associated protein 1 (PRAX-1). Mammals contain a third protein, RIM-BP3. RIM-BP1 and RIM-BP2 are predominantly expressed in the brain where they display overlapping but distinct expression patterns, while RIM-BP3 is almost exclusively expressed in the testis and is essential in spermiogenesis. The SH3 domains of RIM-BPs bind to the PxxP motifs of RIM1, RIM2, and L-type (alpha1D) and N-type (alpha1B) calcium channel subunits. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 1039756550 235 ALFDYDPKEDKAIPCKEAGLSFRKGDILQI---MSQDDVtwwqakHEGDANPRAGLIPSKHFQE 295
Cdd:cd12013     4 ALFDYDPRESSPNVDAEVELSFRAGDIITVfgeMDEDGF------YYGELNGQRGLVPSNFLEE 61

PDZ domain of Rab3-interacting molecule 1 (RIM), RIM2, piccolo and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of RIM, RIM2, piccolo and related domains. RIM proteins and Gallus gallus protein piccolo (also called aczonin) are involved in neurotransmitter release at presynaptic active zones, the site of vesicle fusion. A protein complex containing RIM proteins positions synaptic vesicles containing synaptotagmin at the active zone. RIM proteins simultaneously activate docking and priming of synaptic vesicles and recruit Ca2+-channels to active zones, thereby connecting primed synaptic vesicles to Ca2+-channels. RIM binding to vesicular Rab proteins (Rab3 and Rab27 isoforms) mediates vesicle docking; RIM binding to Munc13 activates vesicle priming; RIM binding to the Ca2+-channel, both directly and indirectly via RIM-BP, recruits the Ca2+-channels. The RIM PDZ domain interacts with the C-termini of N- and P/Q-type voltage-gated Ca2+-channels. RIM1, RIM2 and piccolo also participate in regulated exocytosis through binding cAMP-GEFII (cAMP-binding protein-guanidine nucleotide exchange factor II). The piccolo PDZ domain binds cAMP-GEFII. RIM2 also plays a role in dendrite formation by melanocytes. Caenorhabditis elegans RIM (also known as unc-10) may be involved in the regulation of defecation and daumone response. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This RIM-like family domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

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gi 1039756550 158 QTGAItVARIMRGGAADRSGLIHVGDELREVNGIPVEDKRPEEIIKILSQSKG 210
Cdd:cd06714    37 RLGAY-VTKVKPGSVADTVGHLREGDEVLEWNGISLQGKTFEEVQDIISQSKG 88

PDZ domain 2 of glutamate receptor-interacting protein 1 (GRIP1) and GRIP2, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) binding proteins GRIP1 (ABP/GRIP2) and GRIP2, and related domains. GRIP1 and GRIP2 each have 7 PDZ domains. The interaction of GRIP1 and GRIP2 with GluA2/3 (AMPAR subunit) regulates AMPAR trafficking and synaptic targeting. GRIP1 has an essential role in regulating AMPAR trafficking during synaptic plasticity and learning and memory. GRIP1 and GRIP2 interact with a variety of other proteins associated with protein trafficking and internalization, for example GRIP1 also interacts with KIF5 (also known as kinesin 1), EphB receptors, scaffold protein liprin-alpha, and the rasGEF GRASP-1. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This GRIP family PDZ2 domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

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gi 1039756550 140 IRLVKNSEPLGATI-----KKDEQTGAITVARIMRGGAADRSGLIHVGDELREVNGIPVEDKRPEEIIKILSQSKGAITF 214
Cdd:cd06681     5 VTLEKEGNSFGFVIrggahEDRNKSRPLTVTHVRPGGPADREGTIKPGDRLLSVDGISLHGATHAEAMSILKQCGQEATL 84

                  ..
gi 1039756550 215 KI 216
Cdd:cd06681    85 LI 86

PDZ domain 2 of tyrosine kinase PTPN13, FERM and PDZ domain-containing protein 2 (FRMPD2), and similar domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 2 of human PTPN13, and related domains. PTPN13, also known as Fas-associated protein-tyrosine phosphatase 1 (FAP-1), protein-tyrosine phosphatase 1E (PTP-E1), and protein-tyrosine phosphatase (PTPL1), negatively regulates FAS-mediated apoptosis and NGFR-mediated pro-apoptotic signaling, and may also regulate phosphoinositide 3-kinase (PI3K) signaling. It contains 5 PDZ domains; interaction partners of its second PDZ domain (PDZ2) include the Fas receptor (TNFRSF6) and thyroid receptor-interacting protein 6 (TRIP6). The second PDZ (PDZ2) domain, but not PDZ1 or PDZ3, of FRMPD2 binds to GluN2A and GluN2B, two subunits of N-methyl-d-aspartic acid (NMDA) receptors. Other binding partners of the FRMPDZ2 PDZ2 domain include NOD2, and catenin family members, delta catenin (CTNND2), armadillo repeat gene deleted in velo-cardio-facial syndrome (ARVCF) and p0071 (also known as plakophilin 4; PKP4). PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This PTPN13-like family PDZ2 domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

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gi 1039756550 160 GAITVARIMRGGAADRSGLIHVGDELREVNGIPVEDKRPEEIIKILSQSKGAITF 214
Cdd:cd06792    29 GGIYVKSLVPGGAAEQDGRIQKGDRLLEVNGVSLEGVTHKQAVECLKNAGQVVTL 83