RUN domain found in small G protein signaling modulator 3 (SGSM3) and similar proteins; SGSM3, also called RUN and TBC1 domain-containing protein 3 (RUTBC3), or Merlin-Associated Protein (MAP), or Rab-GTPase-activating protein-like protein (RabGAPLP), may play a cooperative role in NF2-mediated growth suppression of cells. This model contains the RUN domain of SGSM3.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 686661116 451 DEHCWVGELNGLRGWFPAKFVEVLDERSKE--------------------------ALFEHGLKKPSLLGGACHPWLFIE 504
Cdd:cd17688    1 DEHCWVGELNGLRGWFPAKFVELLDERSKEysiagddsvtetitdlvrgrlcpalkAIFEHGLKKPSLLGGACHPWLFIE 80

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 686661116 505 EAAGREVERDFASVYSRLVLCKTFRLDEDGKVLTPEELLYRAVQSVNVTHDAVHAQMDVKLRSLICVGLNEQVLHLWLEV 584
Cdd:cd17688   81 EAASKEVEKDFNSVYSRLVLCKTFRLDEDGKVLTPEELLYRSVQAVNMSHDAAHAQMDVKLRSLICVGLNEQVLHLWLEV 160

                        170       180       190       200       210
                 ....*....|....*....|....*....|....*....|....*....|....
gi 686661116 585 LCSSLPTVEKWYQPWSFLRSPGWVQIKCELRVLCCFAFSLSQDWELPAKREAQQ 638
Cdd:cd17688  161 LCSSVQIVEKWYHPWSFLRSPGWVQIKCELRVLSQFSFNLSLDWELPKKRTKKS 214

Src Homology 3 domain of Small G protein Signaling Modulator 3; SGSM3 is also called Merlin-associated protein (MAP), RUN and SH3 domain-containing protein (RUSC3), RUN and TBC1 domain-containing protein 3 (RUTBC3), Rab GTPase-activating protein 5 (RabGAP5), or Rab GAP-like protein (RabGAPLP). It is expressed ubiquitously and functions as a regulator of small G protein RAP- and RAB-mediated neuronal signaling. It is involved in modulating NGF-mediated neurite outgrowth and differentiation. It also interacts with the tumor suppressor merlin and may play a role in the merlin-associated suppression of cell growth. SGSM3 contains TBC, SH3, and RUN 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
                 ....*....|....*....|....*....|....*....|....*....|...
gi 686661116 421 RAKALLDFERHDDDELGFRKNDIITIVSQKDEHCWVGELNGLRGWFPAKFVEV 473
Cdd:cd11813    1 RAKALLDFERHDDDELGFRKNDIITIISQKDEHCWVGELNGLRGWFPAKFVEL 53

RUN domain found in small G protein signaling modulator 3 (SGSM3) and similar proteins; SGSM3, also called RUN and TBC1 domain-containing protein 3 (RUTBC3), or Merlin-Associated Protein (MAP), or Rab-GTPase-activating protein-like protein (RabGAPLP), may play a cooperative role in NF2-mediated growth suppression of cells. This model contains the RUN domain of SGSM3.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 686661116 451 DEHCWVGELNGLRGWFPAKFVEVLDERSKE--------------------------ALFEHGLKKPSLLGGACHPWLFIE 504
Cdd:cd17688    1 DEHCWVGELNGLRGWFPAKFVELLDERSKEysiagddsvtetitdlvrgrlcpalkAIFEHGLKKPSLLGGACHPWLFIE 80

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 686661116 505 EAAGREVERDFASVYSRLVLCKTFRLDEDGKVLTPEELLYRAVQSVNVTHDAVHAQMDVKLRSLICVGLNEQVLHLWLEV 584
Cdd:cd17688   81 EAASKEVEKDFNSVYSRLVLCKTFRLDEDGKVLTPEELLYRSVQAVNMSHDAAHAQMDVKLRSLICVGLNEQVLHLWLEV 160

                        170       180       190       200       210
                 ....*....|....*....|....*....|....*....|....*....|....
gi 686661116 585 LCSSLPTVEKWYQPWSFLRSPGWVQIKCELRVLCCFAFSLSQDWELPAKREAQQ 638
Cdd:cd17688  161 LCSSVQIVEKWYHPWSFLRSPGWVQIKCELRVLSQFSFNLSLDWELPKKRTKKS 214

Rab-GTPase-TBC domain; Identification of a TBC domain in GYP6_YEAST and GYP7_YEAST, which are GTPase activator proteins of yeast Ypt6 and Ypt7, implies that these domains are GTPase activator proteins of Rab-like small GTPases.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 686661116   94 KQIEKDLLRTMPSNacFASMGSIGVPRLRRVLRALAWLYPEIGYCQGTGMVAACLLL-FLEEEDAFWMMSAIIEDLLPAS 172
Cdd:pfam00566  10 EQIEKDVPRTFPHS--FFFDNGPGQNSLRRILKAYSIYNPDVGYCQGMNFIAAPLLLvYLDEEDAFWCFVSLLENYLLRD 87

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 686661116  173 YFSTTLLGVQTDQRVLRHLIVQYLPRLDKLLQEHDIELSLITLHWFLTAFASVVDIKLLLRIWDLFFYEGSRV-LFQLTL 251
Cdd:pfam00566  88 FYTPDFPGLKRDLYVFEELLKKKLPKLYKHLKELGLDPDLFASQWFLTLFAREFPLSTVLRIWDYFFLEGEKFvLFRVAL 167

                         170
                  ....*....|.
gi 686661116  252 GMLHLKEEELI 262
Cdd:pfam00566 168 AILKRFREELL 178

Src Homology 3 domain of Small G protein Signaling Modulator 3; SGSM3 is also called Merlin-associated protein (MAP), RUN and SH3 domain-containing protein (RUSC3), RUN and TBC1 domain-containing protein 3 (RUTBC3), Rab GTPase-activating protein 5 (RabGAP5), or Rab GAP-like protein (RabGAPLP). It is expressed ubiquitously and functions as a regulator of small G protein RAP- and RAB-mediated neuronal signaling. It is involved in modulating NGF-mediated neurite outgrowth and differentiation. It also interacts with the tumor suppressor merlin and may play a role in the merlin-associated suppression of cell growth. SGSM3 contains TBC, SH3, and RUN 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
                 ....*....|....*....|....*....|....*....|....*....|...
gi 686661116 421 RAKALLDFERHDDDELGFRKNDIITIVSQKDEHCWVGELNGLRGWFPAKFVEV 473
Cdd:cd11813    1 RAKALLDFERHDDDELGFRKNDIITIISQKDEHCWVGELNGLRGWFPAKFVEL 53

Src homology 3 domains; Src homology 3 (SH3) domains bind to target proteins through sequences containing proline and hydrophobic amino acids. Pro-containing polypeptides may bind to SH3 domains in 2 different binding orientations.

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|....*
gi 686661116   419 RRRAKALLDFERHDDDELGFRKNDIITIVSQKDEHCWVGELN-GLRGWFPAKFVE 472
Cdd:smart00326   2 GPQVRALYDYTAQDPDELSFKKGDIITVLEKSDDGWWKGRLGrGKEGLFPSNYVE 56

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.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*..
gi 686661116  423 KALLDFERHDDDELGFRKNDIITIVSQKDEHCWVGELN-GLRGWFPA 468
Cdd:pfam00018   1 VALYDYTAQEPDELSFKKGDIIIVLEKSEDGWWKGRNKgGKEGLIPS 47

RUN domain found in small G protein signaling modulator 3 (SGSM3) and similar proteins; SGSM3, also called RUN and TBC1 domain-containing protein 3 (RUTBC3), or Merlin-Associated Protein (MAP), or Rab-GTPase-activating protein-like protein (RabGAPLP), may play a cooperative role in NF2-mediated growth suppression of cells. This model contains the RUN domain of SGSM3.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 686661116 451 DEHCWVGELNGLRGWFPAKFVEVLDERSKE--------------------------ALFEHGLKKPSLLGGACHPWLFIE 504
Cdd:cd17688    1 DEHCWVGELNGLRGWFPAKFVELLDERSKEysiagddsvtetitdlvrgrlcpalkAIFEHGLKKPSLLGGACHPWLFIE 80

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 686661116 505 EAAGREVERDFASVYSRLVLCKTFRLDEDGKVLTPEELLYRAVQSVNVTHDAVHAQMDVKLRSLICVGLNEQVLHLWLEV 584
Cdd:cd17688   81 EAASKEVEKDFNSVYSRLVLCKTFRLDEDGKVLTPEELLYRSVQAVNMSHDAAHAQMDVKLRSLICVGLNEQVLHLWLEV 160

                        170       180       190       200       210
                 ....*....|....*....|....*....|....*....|....*....|....
gi 686661116 585 LCSSLPTVEKWYQPWSFLRSPGWVQIKCELRVLCCFAFSLSQDWELPAKREAQQ 638
Cdd:cd17688  161 LCSSVQIVEKWYHPWSFLRSPGWVQIKCELRVLSQFSFNLSLDWELPKKRTKKS 214

Rab-GTPase-TBC domain; Identification of a TBC domain in GYP6_YEAST and GYP7_YEAST, which are GTPase activator proteins of yeast Ypt6 and Ypt7, implies that these domains are GTPase activator proteins of Rab-like small GTPases.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 686661116   94 KQIEKDLLRTMPSNacFASMGSIGVPRLRRVLRALAWLYPEIGYCQGTGMVAACLLL-FLEEEDAFWMMSAIIEDLLPAS 172
Cdd:pfam00566  10 EQIEKDVPRTFPHS--FFFDNGPGQNSLRRILKAYSIYNPDVGYCQGMNFIAAPLLLvYLDEEDAFWCFVSLLENYLLRD 87

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 686661116  173 YFSTTLLGVQTDQRVLRHLIVQYLPRLDKLLQEHDIELSLITLHWFLTAFASVVDIKLLLRIWDLFFYEGSRV-LFQLTL 251
Cdd:pfam00566  88 FYTPDFPGLKRDLYVFEELLKKKLPKLYKHLKELGLDPDLFASQWFLTLFAREFPLSTVLRIWDYFFLEGEKFvLFRVAL 167

                         170
                  ....*....|.
gi 686661116  252 GMLHLKEEELI 262
Cdd:pfam00566 168 AILKRFREELL 178

Src Homology 3 domain of Small G protein Signaling Modulator 3; SGSM3 is also called Merlin-associated protein (MAP), RUN and SH3 domain-containing protein (RUSC3), RUN and TBC1 domain-containing protein 3 (RUTBC3), Rab GTPase-activating protein 5 (RabGAP5), or Rab GAP-like protein (RabGAPLP). It is expressed ubiquitously and functions as a regulator of small G protein RAP- and RAB-mediated neuronal signaling. It is involved in modulating NGF-mediated neurite outgrowth and differentiation. It also interacts with the tumor suppressor merlin and may play a role in the merlin-associated suppression of cell growth. SGSM3 contains TBC, SH3, and RUN 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
                 ....*....|....*....|....*....|....*....|....*....|...
gi 686661116 421 RAKALLDFERHDDDELGFRKNDIITIVSQKDEHCWVGELNGLRGWFPAKFVEV 473
Cdd:cd11813    1 RAKALLDFERHDDDELGFRKNDIITIISQKDEHCWVGELNGLRGWFPAKFVEL 53

RUN domain; RUN domain, named after RPIP8 (Rap2 interacting protein 8), UNC-14 and NESCA (new molecule containing SH3 at the carboxyl-terminus), is a less conserved protein motif that comprises six conserved regions, which in some proteins have considerable insertions between them. The domain core is thought to take up a predominantly alpha fold, with basic amino acids in regions A and D possibly playing a functional role in interactions with Ras GTPases. RUN domains are often found in proteins linked particularly to the functions of GTPases in the Rap and Rab families, suggesting the RUN domain may be involved in Rab-mediated membrane trafficking, possibly as a Rab-binding site. RUN domain-containing proteins could hence play important roles in multiple Ras-like GTPase signalling pathways.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 686661116 480 EALFEHGLKKPSLLGGACHPWLFIEEAAGREVERDfasvysrlvlcktfrldedgkvltpeelLYRAVQSVNVTHDAvhA 559
Cdd:cd17671   39 EAILSHGLKPKRFGGGKVSFWDFLEALEKLLPAPS----------------------------LKQAIRDINSLSNV--K 88

                         90       100       110       120       130       140
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 686661116 560 QMDVKLRSLICVGLNEQVLHLWLEVLCSSLPTVEKWYQPWSFLRSP-GWVQIKCELRVLCCFAFSL 624
Cdd:cd17671   89 TDDGRGRAWIRLALNEKSLESYLAALLSDQSLLRKYYEPWALLRDPeEAELFLSLLVGLSSLDFNL 154

domain involved in Ras-like GTPase signaling;

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 686661116   565 LRSLICVGLNEQVLHLWLEVLCSSLPTVEKWYQPWSFLRSP-GWVQIKCELRVLCCFAFSLSQD 627
Cdd:smart00593   1 FRAWIRLALNEKLLSSWLNLLLSDEELLSKYYEPWAFLRDPeEGEQLLGLLVGLSALDFNLPVD 64

Src Homology 3 domain superfamily; Src Homology 3 (SH3) domains are protein interaction domains that bind proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. Thus, they are referred to as proline-recognition domains (PRDs). SH3 domains are less selective and show more diverse specificity compared to other PRDs. They have been shown to bind peptide sequences that lack the PxxP motif; examples include the PxxDY motif of Eps8 and the RKxxYxxY sequence in SKAP55. SH3 domain containing proteins 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, among others. Many members of this superfamily are adaptor proteins that associate with a number of protein partners, facilitating complex formation and signal transduction.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|.
gi 686661116 421 RAKALLDFERHDDDELGFRKNDIITIVSQKDEHCWVGELNGLR-GWFPAKF 470
Cdd:cd00174    1 YARALYDYEAQDDDELSFKKGDIITVLEKDDDGWWEGELNGGReGLFPANY 51

RUN domain found in RUN domain-containing protein 1 (RUNDC1) and similar proteins; RUN domain-containing protein 1 (RUNDC1) is thought to a role as p53/TP53 inhibitor and as such may have oncogenic activity. This model contains the RUN domain.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 686661116 481 ALFEHGLKKPS------LLGGAC------------HPW-LFI---EEAAGREverdFASVYSRLvLCKTFRLDE-DGKVL 537
Cdd:cd17683   86 DLLQHGLMSPSsssslvPAILACcpsssssspqamHAWdLFLkyyELKNGRE----FNESPARK-LSQSFQLDIvGGKAI 160

                         90       100       110       120       130       140       150
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 686661116 538 TPEELLYRAVQSVNVTHDAVHAQMDVKLRSLICVGLNEQVLHLWLEVLCSSLPTVEKWYQPWSFLRSPGW 607
Cdd:cd17683  161 TPKQSLLTAIGNIISSHEPLKRSPDSHFKAFVCAALNEKRLVSWLRLILRSPTLVDEHYQPWSYVARTGF 230

First Src Homology 3 domain (SH3A) of CD2-associated protein and similar proteins; This subfamily is composed of the first SH3 domain (SH3A) of CD2AP, CIN85 (Cbl-interacting protein of 85 kDa), and similar domains. CD2AP and CIN85 are adaptor proteins that bind to protein partners and assemble complexes that have been implicated in T cell activation, kidney function, and apoptosis of neuronal cells. They also associate with endocytic proteins, actin cytoskeleton components, and other adaptor proteins involved in receptor tyrosine kinase (RTK) signaling. CD2AP and the main isoform of CIN85 contain three SH3 domains, a proline-rich region, and a C-terminal coiled-coil domain. All of these domains enable CD2AP and CIN85 to bind various protein partners and assemble complexes that have been implicated in many different functions. SH3A of both proteins bind to an atypical PXXXPR motif at the C-terminus of Cbl and the cytoplasmic domain of the cell adhesion protein CD2. CIN85 SH3A binds to internal proline-rich motifs within the proline-rich region; this intramolecular interaction serves as a regulatory mechanism to keep CIN85 in a closed conformation, preventing the recruitment of other proteins. CIN85 SH3A has also been shown to bind ubiquitin. 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 686661116 422 AKALLDFERHDDDELGFRKNDIITIVSQKDEHCWVGELNGLRGWFPAKFVEV 473
Cdd:cd11873    2 VIVEFDYDAEEPDELTLKVGDIITNVKKMEEGWWEGTLNGKRGMFPDNFVKV 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.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*..
gi 686661116  423 KALLDFERHDDDELGFRKNDIITIVSQKDEHCWVGELN-GLRGWFPA 468
Cdd:pfam00018   1 VALYDYTAQEPDELSFKKGDIIIVLEKSEDGWWKGRNKgGKEGLIPS 47

Src homology 3 domain of Nitric Oxide Synthase TRaffic INducer; Nostrin is expressed in endothelial and epithelial cells and is involved in the regulation, trafficking and targeting of endothelial NOS (eNOS). It facilitates the endocytosis of eNOS by coordinating the functions of dynamin and the Wiskott-Aldrich syndrome protein (WASP). Increased expression of Nostrin may be correlated to preeclampsia. Nostrin contains an N-terminal F-BAR domain and a C-terminal 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 686661116 421 RAKALLDFERHDDDELGFRKNDIITIVSQKDEHCWVGELNGLRGWFPAKFVEV 473
Cdd:cd11823    1 RCKALYSYTANREDELSLQPGDIIEVHEKQDDGWWLGELNGKKGIFPATYVEE 53

Fifth Src homology 3 domain (or SH3E) of Intersectin; Intersectins (ITSNs) are adaptor proteins that function in exo- and endocytosis, actin cytoskeletal reorganization, and signal transduction. They are essential for initiating clathrin-coated pit formation. They bind to many proteins through their multidomain structure and facilitate the assembly of multimeric complexes. Vertebrates contain two ITSN proteins, ITSN1 and ITSN2, which exist in alternatively spliced short and long isoforms. The short isoforms contain two Eps15 homology domains (EH1 and EH2), a coiled-coil region and five SH3 domains (SH3A-E), while the long isoforms, in addition, contain RhoGEF (also called Dbl-homologous or DH), Pleckstrin homology (PH) and C2 domains. ITSN1 and ITSN2 are both widely expressed, with variations depending on tissue type and stage of development. The fifth SH3 domain (or SH3E) of ITSN1 has been shown to bind many protein partners including SGIP1, Sos1, dynamin1/2, CIN85, c-Cbl, SHIP2, N-WASP, and synaptojanin-1, among others. 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 686661116 424 ALLDFERHDDDELGFRKNDIITIVSQKDEHCWVGELNGLRGWFPAKFVEV 473
Cdd:cd11840    4 ALFPYTAQNEDELSFQKGDIINVLSKDDPDWWRGELNGQTGLFPSNYVEP 53

Src homology 3 domain of Signal Transducing Adaptor Molecules; STAMs were discovered as proteins that are highly phosphorylated following cytokine and growth factor stimulation. They function in cytokine signaling and surface receptor degradation, as well as regulate Golgi morphology. They associate with many proteins including Jak2 and Jak3 tyrosine kinases, Hrs, AMSH, and UBPY. STAM adaptor proteins contain VHS (Vps27, Hrs, STAM homology), ubiquitin interacting (UIM), and SH3 domains. There are two vertebrate STAMs, STAM1 and STAM2, which may be functionally redundant; vertebrate STAMs contain ITAM motifs. They are part of the endosomal sorting complex required for transport (ESCRT-0). STAM2 deficiency in mice did not cause any obvious abnormality, while STAM1 deficiency resulted in growth retardation. Loss of both STAM1 and STAM2 in mice proved lethal, indicating that STAMs are important for embryonic development. 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 686661116 420 RRAKALLDFERHDDDELGFRKNDIITIVSQKDEHCWVGELNGLRGWFPAKFV 471
Cdd:cd11820    1 RKVRALYDFEAAEDNELTFKAGEIITVLDDSDPNWWKGSNHRGEGLFPANFV 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
                 ....*....|....*....|....*....|....*....|....*....|.
gi 686661116 422 AKALLDFERHDDDELGFRKNDIITIVSQKDEHCWVGELNGLRGWFPAKFVE 472
Cdd:cd11949    2 VQALFDFDPQEDGELGFRRGDFIEVMDNSDPNWWKGACHGQTGMFPRNYVT 52

Src Homology 3 domain of GTPase Regulator Associated with Focal adhesion kinase and similar proteins; This subfamily is composed of Rho GTPase activating proteins (GAPs) with similarity to GRAF. Members contain an N-terminal BAR domain, followed by a Pleckstrin homology (PH) domain, a Rho GAP domain, and a C-terminal SH3 domain. Although vertebrates harbor four Rho GAPs in the GRAF subfamily including GRAF, GRAF2, GRAF3, and Oligophrenin-1 (OPHN1), only three are included in this model. OPHN1 contains the BAR, PH and GAP domains, but not the C-terminal SH3 domain. GRAF and GRAF2 show GAP activity towards RhoA and Cdc42. GRAF influences Rho-mediated cytoskeletal rearrangements and binds focal adhesion kinase. GRAF2 regulates caspase-activated p21-activated protein kinase-2. The SH3 domain of GRAF and GRAF2 binds PKNbeta, a target of the small GTPase Rho. SH3 domains bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs; they play a role in the regulation of enzymes by intramolecular interactions, changing the subcellular localization of signal pathway components and mediate multiprotein complex assemblies.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|...
gi 686661116 421 RAKALLDFERHDDDELGFRKNDIITIVSQKDEHCW-VGELNGLRGWFPAKFVE 472
Cdd:cd11882    1 RARALYACKAEDESELSFEPGQIITNVQPSDEPGWlEGTLNGRTGLIPENYVE 53

Src homology 3 domain of Signal Transducing Adaptor Molecule 1; STAM1 is part of the endosomal sorting complex required for transport (ESCRT-0) and is involved in sorting ubiquitinated cargo proteins from the endosome. It may also be involved in the regulation of IL2 and GM-CSF mediated signaling, and has been implicated in neural cell survival. STAMs were discovered as proteins that are highly phosphorylated following cytokine and growth factor stimulation. They function in cytokine signaling and surface receptor degradation, as well as regulate Golgi morphology. They associate with many proteins including Jak2 and Jak3 tyrosine kinases, Hrs, AMSH, and UBPY. STAM adaptor proteins contain VHS (Vps27, Hrs, STAM homology), ubiquitin interacting (UIM), and SH3 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
                 ....*....|....*....|....*....|....*....|....*....|..
gi 686661116 420 RRAKALLDFERHDDDELGFRKNDIITIVSQKDEHCWVGELNGLRGWFPAKFV 471
Cdd:cd11964    1 RKVRAIYDFEAAEDNELTFKAGDIITILDDSDPNWWKGETPQGTGLFPSNFV 52

Src homology 3 domain of Ysc84p and similar fungal proteins; This family is composed of the Saccharomyces cerevisiae proteins, Ysc84p (also called LAS17-binding protein 4, Lsb4p) and Lsb3p, and similar fungal proteins. They contain an N-terminal SYLF domain (also called DUF500) and a C-terminal SH3 domain. Ysc84p localizes to actin patches and plays an important in actin polymerization during endocytosis. The N-terminal domain of both Ysc84p and Lsb3p can bind and bundle actin filaments. A study of the yeast SH3 domain interactome predicts that the SH3 domains of Lsb3p and Lsb4p may function as molecular hubs for the assembly of endocytic complexes. 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 686661116 421 RAKALLDFERHDDDELGFRKNDIITIVSQKDEH--CWVGELNGLRGWFPAKFVEV 473
Cdd:cd11842    1 KAVALYDFAGEQPGDLAFQKGDIITILKKSDSQndWWTGRIGGREGIFPANYVEL 55

Src homology 3 domain of Myosins Ie, If, and similar proteins; Myosins Ie (MyoIe) and If (MyoIf) are nonmuscle, unconventional, long tailed, class I myosins containing an N-terminal motor domain and a myosin tail with TH1, TH2, and SH3 domains. MyoIe interacts with the endocytic proteins, dynamin and synaptojanin-1, through its SH3 domain; it may play a role in clathrin-dependent endocytosis. In the kidney, MyoIe is critical for podocyte function and normal glomerular filtration. Mutations in MyoIe is associated with focal segmental glomerulosclerosis, a disease characterized by massive proteinuria and progression to end-stage kidney disease. MyoIf is predominantly expressed in the immune system; it plays a role in immune cell motility and innate immunity. Mutations in MyoIf may be associated with the loss of hearing. The MyoIf gene has also been found to be fused to the MLL (Mixed lineage leukemia) gene in infant acute myeloid leukemias (AML). 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 686661116 421 RAKALLDFERHDDDELGFRKNDIITIVSQKDEHCWVGELNGLRGWFPAKFVE 472
Cdd:cd11827    1 QCKALYAYDAQDTDELSFNEGDIIEILKEDPSGWWTGRLRGKEGLFPGNYVE 52

Src Homology 3 domain of beta-Pak Interactive eXchange factor; Beta-PIX, also called Rho guanine nucleotide exchange factor 7 (ARHGEF7) or Cool (Cloned out of Library)-1, activates small GTPases by exchanging bound GDP for free GTP. It acts as a GEF for both Cdc42 and Rac 1, and plays important roles in regulating neuroendocrine exocytosis, focal adhesion maturation, cell migration, synaptic vesicle localization, and insulin secretion. PIX proteins contain an N-terminal SH3 domain followed by RhoGEF (also called Dbl-homologous or DH) and Pleckstrin Homology (PH) domains, and a C-terminal leucine-zipper domain for dimerization. The SH3 domain of PIX binds to an atypical PxxxPR motif in p21-activated kinases (PAKs) with high affinity. The binding of PAKs to PIX facilitate the localization of PAKs to focal complexes and also localizes PAKs to PIX targets Cdc43 and Rac, leading to the activation of PAKs. 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 686661116 423 KALLDFERHDDDELGFRKNDIITIVSQKDEHCWVGELNGLRGWFPAKFV 471
Cdd:cd12061    3 RAKFNFQQTNEDELSFSKGDVIHVTRVEEGGWWEGTHNGRTGWFPSNYV 51

Src homology 3 domain of Phospholipase C (PLC) gamma; PLC catalyzes the hydrolysis of phosphatidylinositol (4,5)-bisphosphate [PtdIns(4,5)P2] to produce Ins(1,4,5)P3 and diacylglycerol (DAG) in response to various receptors. Ins(1,4,5)P3 initiates the calcium signaling cascade while DAG functions as an activator of PKC. PLCgamma catalyzes this reaction in tyrosine kinase-dependent signaling pathways. It is activated and recruited to its substrate at the membrane. Vertebrates contain two forms of PLCgamma, PLCgamma1, which is widely expressed, and PLCgamma2, which is primarily found in haematopoietic cells. PLCgamma contains a Pleckstrin homology (PH) domain followed by an elongation factor (EF) domain, two catalytic regions of PLC domains that flank two tandem SH2 domains, followed by a SH3 domain and C2 domain. The SH3 domain of PLCgamma1 directly interacts with dynamin-1 and can serve as a guanine nucleotide exchange factor (GEF). It also interacts with Cbl, inhibiting its phosphorylation and activity. 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 686661116 422 AKALLDFERHDDDELGFRKNDIITIVSQKDEHCWVGELNGLR-GWFPAKFVE 472
Cdd:cd11825    2 VKALYDYRAQRPDELSFCKHAIITNVEKEDGGWWRGDYGGKKqKWFPANYVE 53

Second Src Homology 3 domain of Bzz1 and similar domains; Bzz1 (or Bzz1p) is a WASP/Las17-interacting protein involved in endocytosis and trafficking to the vacuole. It physically interacts with type I myosins and functions in the early steps of endocytosis. Together with other proteins, it induces membrane scission in yeast. Bzz1 contains an N-terminal F-BAR (FES-CIP4 Homology and Bin/Amphiphysin/Rvs), a central coiled-coil, and two C-terminal SH3 domains. This model represents the second C-terminal 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.

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gi 686661116 423 KALLDFERHDDDELGFRKNDIITIVSQKDEHCWV-GELNGLRGWFPAKF 470
Cdd:cd11778    3 EALYDYEAQGDDEISIRVGDRIAVIRGDDGSGWTyGEINGVKGLFPTSY 51

C-terminal Src homology 3 domain of GRB2-related adaptor protein 2; GRAP2 is also called GADS (GRB2-related adapter downstream of Shc), GrpL, GRB2L, Mona, or GRID (Grb2-related protein with insert domain). It is expressed specifically in the hematopoietic system. It 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. It also has roles in antigen-receptor and tyrosine kinase mediated signaling. GRAP2 is unique from other GRB2-like adaptor proteins in that it can be regulated by caspase cleavage. It contains an N-terminal SH3 domain, a central SH2 domain, and a C-terminal SH3 domain. The C-terminal SH3 domain of GRAP2 binds to different motifs found in substrate peptides including the typical PxxP motif in hematopoietic progenitor kinase 1 (HPK1), the RxxK motif in SLP-76 and HPK1, and the RxxxxK motif in phosphatase-like protein HD-PTP. 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 686661116 422 AKALLDFERHDDDELGFRKNDIITIVSQKDEHCWVGELNGLRGWFPAKFVE 472
Cdd:cd11950    2 VRALYDFEALEDDELGFNSGDVIEVLDSSNPSWWKGRLHGKLGLFPANYVA 52

Src homology 3 domain of ArfGAP with SH3 domain, ankyrin repeat and PH domain containing proteins; ASAPs are Arf GTPase activating proteins (GAPs) and they function in regulating cell growth, migration, and invasion. They contain an N-terminal BAR domain, followed by a Pleckstrin homology (PH) domain, an Arf GAP domain, ankyrin (ANK) repeats, and a C-terminal SH3 domain. Vertebrates contain at least three members, ASAP1, ASAP2, and ASAP3, but some ASAP3 proteins do not seem to harbor a C-terminal SH3 domain. ASAP1 and ASAP2 show GTPase activating protein (GAP) activity towards Arf1 and Arf5. They do not show GAP activity towards Arf6, but are able to mediate Arf6 signaling by binding stably to GTP-Arf6. ASAP3 is an Arf6-specific GAP. 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 686661116 421 RAKALLDFERHDDDELGFRKNDIITIVSQKDEHCWVGELNG---LRGWFPAKF 470
Cdd:cd11821    1 RVRALYDCQADNDDELTFSEGEIIVVTGEEDDEWWEGHIEGdpsRRGVFPVSF 53

First Src homology 3 domain (or SH3A) of Intersectin; Intersectins (ITSNs) are adaptor proteins that function in exo- and endocytosis, actin cytoskeletal reorganization, and signal transduction. They are essential for initiating clathrin-coated pit formation. They bind to many proteins through their multidomain structure and facilitate the assembly of multimeric complexes. Vertebrates contain two ITSN proteins, ITSN1 and ITSN2, which exist in alternatively spliced short and long isoforms. The short isoforms contain two Eps15 homology domains (EH1 and EH2), a coiled-coil region and five SH3 domains (SH3A-E), while the long isoforms, in addition, contain RhoGEF (also called Dbl-homologous or DH), Pleckstrin homology (PH) and C2 domains. ITSN1 and ITSN2 are both widely expressed, with variations depending on tissue type and stage of development. The first SH3 domain (or SH3A) of ITSN1 has been shown to bind many proteins including Sos1, dynamin1/2, CIN85, c-Cbl, PI3K-C2, SHIP2, N-WASP, and CdGAP, among others. 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 686661116 421 RAKALLDFERHDDDELGFRKNDIITI-VSQKDEHCWV-GELNGLRGWFPAKFVE 472
Cdd:cd11836    1 KYRALYAFEARNPDEISFQPGDIIQVdESQVAEPGWLaGELKGKTGWFPANYVE 54

Src homology 3 domain of Signal Transducing Adaptor Molecule 2; STAM2, also called EAST (Epidermal growth factor receptor-associated protein with SH3 and TAM domain) or Hbp (Hrs binding protein), is part of the endosomal sorting complex required for transport (ESCRT-0). It plays a role in sorting mono-ubiquinated endosomal cargo for trafficking to the lysosome for degradation. It is also involved in the regulation of exocytosis. STAMs were discovered as proteins that are highly phosphorylated following cytokine and growth factor stimulation. They function in cytokine signaling and surface receptor degradation, as well as regulate Golgi morphology. They associate with many proteins including Jak2 and Jak3 tyrosine kinases, Hrs, AMSH, and UBPY. STAM adaptor proteins contain VHS (Vps27, Hrs, STAM homology), ubiquitin interacting (UIM), and SH3 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.

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gi 686661116 420 RRAKALLDFERHDDDELGFRKNDIITIVSQKDEHCWVGELNGLRGWFPAKFV 471
Cdd:cd11963    2 RKVRALYDFEAVEDNELTFKHGEIIIVLDDSDANWWKGENHRGVGLFPSNFV 53

Src homology 3 domain of Abl Interactor proteins; Abl interactor (Abi) proteins are adaptor proteins serving as binding partners and substrates of Abl tyrosine kinases. They are involved in regulating actin cytoskeletal reorganization and play important roles in membrane-ruffling, endocytosis, cell motility, and cell migration. They localize to sites of actin polymerization in epithelial adherens junction and immune synapses, as well as to the leading edge of lamellipodia. Vertebrates contain two Abi proteins, Abi1 and Abi2. Abi1 displays a wide expression pattern while Abi2 is highly expressed in the eye and brain. Abi proteins contain a homeobox homology domain, a proline-rich region, and a SH3 domain. The SH3 domain of Abi binds to a PxxP motif in Abl. 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 686661116 423 KALLDFERHDDDELGFRKNDIITIVSQKDEHCWVGELNGLRGWFPAKFVE 472
Cdd:cd11826    3 VALYDYTADKDDELSFQEGDIIYVTKKNDDGWYEGVLNGVTGLFPGNYVE 52

First Src Homology 3 domain of Sorbin and SH3 domain containing (Sorbs) proteins and similar domains; This family, also called the vinexin family, is composed predominantly of adaptor proteins containing one sorbin homology (SoHo) and three SH3 domains. Members include the first SH3 domains of Sorbs1 (or ponsin), Sorbs2 (or ArgBP2), Vinexin (or Sorbs3), and similar domains. They are involved in the regulation of cytoskeletal organization, cell adhesion, and growth factor signaling. Members of this family bind multiple partners including signaling molecules like c-Abl, c-Arg, Sos, and c-Cbl, as well as cytoskeletal molecules such as vinculin and afadin. They may have overlapping functions. 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 686661116 422 AKALLDFERHDDDELGFRKNDIITIVSQKDEHCWVGELNGLRGWFPAKFVEV 473
Cdd:cd11781    2 ARALYPFKAQSAKELSLKKGDIIYIRRQIDKNWYEGEHNGRVGIFPASYVEI 53

Src Homology 3 domain of Sorting nexin 18; SNX18 is localized to peripheral endosomal structures, and acts in a trafficking pathway that is clathrin-independent but relies on AP-1 and PACS1. It binds FIP5 and is required for apical lumen formation. It may also play a role in axonal elongation. SNXs are Phox homology (PX) domain containing proteins that are involved in regulating membrane traffic and protein sorting in the endosomal system. SNX18 also contains BAR and SH3 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.

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gi 686661116 421 RAKALLDFERHDDDELGFRKNDIITIVSQKDEHCWVGELN--GLRGWFPAKFVEV 473
Cdd:cd11897    1 RARALYDFRSENPGEISLREHEVLSLCSEQDIEGWLEGVNsrGDRGLFPASYVEV 55

Second Src Homology 3 domain (SH3B) of CD2-associated protein and similar proteins; This subfamily is composed of the second SH3 domain (SH3B) of CD2AP, CIN85 (Cbl-interacting protein of 85 kDa), and similar domains. CD2AP and CIN85 are adaptor proteins that bind to protein partners and assemble complexes that have been implicated in T cell activation, kidney function, and apoptosis of neuronal cells. They also associate with endocytic proteins, actin cytoskeleton components, and other adaptor proteins involved in receptor tyrosine kinase (RTK) signaling. CD2AP and the main isoform of CIN85 contain three SH3 domains, a proline-rich region, and a C-terminal coiled-coil domain. All of these domains enable CD2AP and CIN85 to bind various protein partners and assemble complexes that have been implicated in many different functions. SH3B of both proteins have been shown to bind to Cbl. In the case of CD2AP, its SH3B binds to Cbl at a site distinct from the c-Cbl/SH3A binding site. The CIN85 SH3B also binds ubiquitin. 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 686661116 421 RAKALLDFERHDDDELGFRKNDIITIVSQKDEHCWVGELNGLRGWFPAKFVEV 473
Cdd:cd11874    1 RCKVLFSYTPQNEDELELKVGDTIEVLGEVEEGWWEGKLNGKVGVFPSNFVKE 53

First Src Homology 3 domain (SH3A) of Cbl-interacting protein of 85 kDa; CIN85, also called SH3 domain-containing kinase-binding protein 1 (SH3KBP1) or CD2-binding protein 3 (CD2BP3) or Ruk, is an adaptor protein that is involved in the downregulation of receptor tyrosine kinases by facilitating endocytosis through interaction with endophilin-associated ubiquitin ligase Cbl proteins. It is also important in many other cellular processes including vesicle-mediated transport, cytoskeletal remodelling, apoptosis, cell adhesion and migration, and viral infection, among others. CIN85 exists as multiple variants from alternative splicing; the main variant contains three SH3 domains, a proline-rich region, and a C-terminal coiled-coil domain. All of these domains enable CIN85 to bind various protein partners and assemble complexes that have been implicated in many different functions. This alignment model represents the first SH3 domain (SH3A) of CIN85; SH3A binds to internal proline-rich motifs within the proline-rich region. This intramolecular interaction serves as a regulatory mechanism to keep CIN85 in a closed conformation, preventing the recruitment of other proteins. SH3A has also been shown to bind ubiquitin and to an atypical PXXXPR motif at the C-terminus of Cbl and the cytoplasmic end of the cell adhesion protein CD2. 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 686661116 426 LDFERHDDDELGFRKNDIITIVSQKDEHCWVGELNGLRGWFPAKFV 471
Cdd:cd12052    6 FDYKAQHEDELTITVGDIITKIKKDDGGWWEGEIKGRRGLFPDNFV 51

C-terminal (or second) Src homology 3 domain of VAV1 protein; VAV1 is expressed predominantly in the hematopoietic system and it plays an important role in the development and activation of B and T cells. It is activated by tyrosine phosphorylation to function as a guanine nucleotide exchange factor (GEF) for Rho GTPases following cell surface receptor activation, triggering various effects such as cytoskeletal reorganization, transcription regulation, cell cycle progression, and calcium mobilization. It also serves as a scaffold protein and has been shown to interact with Ku70, Socs1, Janus kinase 2, SIAH2, S100B, Abl gene, ZAP-70, SLP76, and Syk, among others. VAV proteins contain several domains that enable their function: N-terminal calponin homology (CH), acidic, RhoGEF (also called Dbl-homologous or DH), Pleckstrin Homology (PH), C1 (zinc finger), SH2, and two SH3 domains. The C-terminal SH3 domain of Vav1 interacts with a wide variety of proteins including cytoskeletal regulators (zyxin), RNA-binding proteins (Sam68), transcriptional regulators, viral proteins, and dynamin 2. 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 686661116 422 AKALLDFERHDDDELGFRKNDIITIVSQKDEH-CWVGELNGLRGWFPAKFVE 472
Cdd:cd11976    2 AKARYDFCARDRSELSLKEGDIIKILNKKGQQgWWRGEIYGRVGWFPANYVE 53

Second Src Homology 3 domain of FCH and double SH3 domains protein 2; FCHSD2 has a domain structure consisting of an N-terminal F-BAR (FES-CIP4 Homology and Bin/Amphiphysin/Rvs), two SH3, and C-terminal proline-rich domains. It has only been characterized in silico and its function is unknown. 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 686661116 423 KALLDFERHDDDELGFRKNDIITIVS---QKDEHCWVGELNGLRGWFPAKFVE 472
Cdd:cd11894    3 KALYDYEGQTDDELSFPEGAIIRILNkenQDDDGFWEGEFNGRIGVFPSVLVE 55