Serine rich Four helix bundle domain of CAS (Crk-Associated Substrate) scaffolding proteins; a protein interaction module; CAS proteins function as molecular scaffolds to regulate protein complexes that are involved in many cellular processes including migration, chemotaxis, apoptosis, differentiation, and progenitor cell function. They mediate the signaling of integrins at focal adhesions where they localize, and thus, regulate cell invasion and survival. Over-expression of these proteins is implicated in poor prognosis, increased metastasis, and resistance to chemotherapeutics in many cancers such as breast, lung, melanoma, and glioblastoma. CAS proteins have also been linked to the pathogenesis of inflammatory disorders, Alzheimer's, Parkinson's, and developmental defects. They share a common domain structure containing protein interaction modules that enable their scaffolding function, including an N-terminal SH3 domain, an unstructured substrate domain that contains many YxxP motifs, a serine-rich four-helix bundle, and a FAT-like C-terminal domain. Vertebrates contain four CAS proteins: BCAR1 (or p130Cas), NEDD9 (or HEF1), EFS (or SIN), and CASS4 (or HEPL). CAS proteins associate with the 14-3-3 family; this interaction is regulated by integrin-mediated cell adhesion. The serine rich four helix bundle domain of BCAR1 has been shown to bind 14-3-3 in a phosphorylation-dependent manner. This domain is structurally similar to other helical bundles found in cell adhesion components such as alpha-catenin, vinculin, and FAK, and may bind other proteins in addition to the 14-3-3 family.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 221330702 434 LELSSALETLAKLQLQTTAAINRLLSFVVPNWRTRAQLEPAIMDLKLAALRLRTTLHDLAEFGEGALGNATRSEDRNLAL 513
Cdd:cd11549    1 LDLDAAMEKLVRLQQEVSSSVSNLLSFVSSNWRSRENLEPNIDEIKTAVDRLRTSLHEFLEFARGALANAANASDKNLQL 80

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 221330702 514 KLRPLVRALRDANKLIHDSSESLDAQGaWSIDQLarsDEKHGCRPPDALDQLMVCAQTLTEDVRSTTSFIQGNASLLFKR 593
Cdd:cd11549   81 KLRRQLQPLEDSHQILSQTSQALDDCN-WSLEAL---VDNSPSNKPDDLDRFVMCARTLPDDAKQLASFIHGNASLLFKR 156

                 ...
gi 221330702 594 QLT 596
Cdd:cd11549  157 APT 159

Serine rich Four helix bundle domain of CAS (Crk-Associated Substrate) scaffolding proteins; a protein interaction module; CAS proteins function as molecular scaffolds to regulate protein complexes that are involved in many cellular processes including migration, chemotaxis, apoptosis, differentiation, and progenitor cell function. They mediate the signaling of integrins at focal adhesions where they localize, and thus, regulate cell invasion and survival. Over-expression of these proteins is implicated in poor prognosis, increased metastasis, and resistance to chemotherapeutics in many cancers such as breast, lung, melanoma, and glioblastoma. CAS proteins have also been linked to the pathogenesis of inflammatory disorders, Alzheimer's, Parkinson's, and developmental defects. They share a common domain structure containing protein interaction modules that enable their scaffolding function, including an N-terminal SH3 domain, an unstructured substrate domain that contains many YxxP motifs, a serine-rich four-helix bundle, and a FAT-like C-terminal domain. Vertebrates contain four CAS proteins: BCAR1 (or p130Cas), NEDD9 (or HEF1), EFS (or SIN), and CASS4 (or HEPL). CAS proteins associate with the 14-3-3 family; this interaction is regulated by integrin-mediated cell adhesion. The serine rich four helix bundle domain of BCAR1 has been shown to bind 14-3-3 in a phosphorylation-dependent manner. This domain is structurally similar to other helical bundles found in cell adhesion components such as alpha-catenin, vinculin, and FAK, and may bind other proteins in addition to the 14-3-3 family.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 221330702 434 LELSSALETLAKLQLQTTAAINRLLSFVVPNWRTRAQLEPAIMDLKLAALRLRTTLHDLAEFGEGALGNATRSEDRNLAL 513
Cdd:cd11549    1 LDLDAAMEKLVRLQQEVSSSVSNLLSFVSSNWRSRENLEPNIDEIKTAVDRLRTSLHEFLEFARGALANAANASDKNLQL 80

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 221330702 514 KLRPLVRALRDANKLIHDSSESLDAQGaWSIDQLarsDEKHGCRPPDALDQLMVCAQTLTEDVRSTTSFIQGNASLLFKR 593
Cdd:cd11549   81 KLRRQLQPLEDSHQILSQTSQALDDCN-WSLEAL---VDNSPSNKPDDLDRFVMCARTLPDDAKQLASFIHGNASLLFKR 156

                 ...
gi 221330702 594 QLT 596
Cdd:cd11549  157 APT 159

C-terminal FAT-like Four helix bundle domain, also called DUF3513, of CAS (Crk-Associated Substrate) scaffolding proteins; a protein interaction module; CAS proteins function as molecular scaffolds to regulate protein complexes that are involved in many cellular processes including migration, chemotaxis, apoptosis, differentiation, and progenitor cell function. They mediate the signaling of integrins at focal adhesions where they localize, and thus, regulate cell invasion and survival. Over-expression of these proteins is implicated in poor prognosis, increased metastasis, and resistance to chemotherapeutics in many cancers such as breast, lung, melanoma, and glioblastoma. CAS proteins have also been linked to the pathogenesis of inflammatory disorders, Alzheimer's, Parkinson's, and developmental defects. They share a common domain structure containing protein interaction modules that enable their scaffolding function, including an N-terminal SH3 domain, an unstructured substrate domain that contains many YxxP motifs, a serine-rich four-helix bundle, and a FAT-like C-terminal domain. Vertebrates contain four CAS proteins: BCAR1 (or p130Cas), NEDD9 (or HEF1), EFS (or SIN), and CASS4 (or HEPL). The FAT-like C-terminal domain of CAS proteins binds to the C-terminal domain of NSPs (novel SH2-containing proteins) to form multidomain signaling modules that mediate cell migration and invasion.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 221330702 693 DKKLVRYYAQQISTHMGNLMQAIDSFLETVEKNQPPKFFIAYGKFVVVSAHNLVTIGDNVYRNISKEALREKILRCTNAL 772
Cdd:cd11564    1 DRQLLLFYSEQCESHFGALQKAIDAFLSSVESNQPPKVFVAHSKFVILSAHKLVFIGDTLCRNVQSADVRNKVLRCSNQL 80

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|....*.
gi 221330702 773 SDALKTCVLKSKKAAAHFPSGSAVQEMVDSVVHINNLARDLKSVML 818
Cdd:cd11564   81 CEALKTVVLATKKAALQYPSVAAVQEMVDRVVELSHHAQQFKTSLG 126

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 221330702    81 YAKAIYDNYADTSDELPFKKGDILTVLEQDTEgfqGWWLCSL-RNRQGLCPGNRLR 135
Cdd:smart00326   4 QVRALYDYTAQDPDELSFKKGDIITVLEKSDD---GWWKGRLgRGKEGLFPSNYVE 56

Serine rich Four helix bundle domain of CAS (Crk-Associated Substrate) scaffolding proteins; a protein interaction module; CAS proteins function as molecular scaffolds to regulate protein complexes that are involved in many cellular processes including migration, chemotaxis, apoptosis, differentiation, and progenitor cell function. They mediate the signaling of integrins at focal adhesions where they localize, and thus, regulate cell invasion and survival. Over-expression of these proteins is implicated in poor prognosis, increased metastasis, and resistance to chemotherapeutics in many cancers such as breast, lung, melanoma, and glioblastoma. CAS proteins have also been linked to the pathogenesis of inflammatory disorders, Alzheimer's, Parkinson's, and developmental defects. They share a common domain structure containing protein interaction modules that enable their scaffolding function, including an N-terminal SH3 domain, an unstructured substrate domain that contains many YxxP motifs, a serine-rich four-helix bundle, and a FAT-like C-terminal domain. Vertebrates contain four CAS proteins: BCAR1 (or p130Cas), NEDD9 (or HEF1), EFS (or SIN), and CASS4 (or HEPL). CAS proteins associate with the 14-3-3 family; this interaction is regulated by integrin-mediated cell adhesion. The serine rich four helix bundle domain of BCAR1 has been shown to bind 14-3-3 in a phosphorylation-dependent manner. This domain is structurally similar to other helical bundles found in cell adhesion components such as alpha-catenin, vinculin, and FAK, and may bind other proteins in addition to the 14-3-3 family.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 221330702 434 LELSSALETLAKLQLQTTAAINRLLSFVVPNWRTRAQLEPAIMDLKLAALRLRTTLHDLAEFGEGALGNATRSEDRNLAL 513
Cdd:cd11549    1 LDLDAAMEKLVRLQQEVSSSVSNLLSFVSSNWRSRENLEPNIDEIKTAVDRLRTSLHEFLEFARGALANAANASDKNLQL 80

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 221330702 514 KLRPLVRALRDANKLIHDSSESLDAQGaWSIDQLarsDEKHGCRPPDALDQLMVCAQTLTEDVRSTTSFIQGNASLLFKR 593
Cdd:cd11549   81 KLRRQLQPLEDSHQILSQTSQALDDCN-WSLEAL---VDNSPSNKPDDLDRFVMCARTLPDDAKQLASFIHGNASLLFKR 156

                 ...
gi 221330702 594 QLT 596
Cdd:cd11549  157 APT 159

C-terminal FAT-like Four helix bundle domain, also called DUF3513, of CAS (Crk-Associated Substrate) scaffolding proteins; a protein interaction module; CAS proteins function as molecular scaffolds to regulate protein complexes that are involved in many cellular processes including migration, chemotaxis, apoptosis, differentiation, and progenitor cell function. They mediate the signaling of integrins at focal adhesions where they localize, and thus, regulate cell invasion and survival. Over-expression of these proteins is implicated in poor prognosis, increased metastasis, and resistance to chemotherapeutics in many cancers such as breast, lung, melanoma, and glioblastoma. CAS proteins have also been linked to the pathogenesis of inflammatory disorders, Alzheimer's, Parkinson's, and developmental defects. They share a common domain structure containing protein interaction modules that enable their scaffolding function, including an N-terminal SH3 domain, an unstructured substrate domain that contains many YxxP motifs, a serine-rich four-helix bundle, and a FAT-like C-terminal domain. Vertebrates contain four CAS proteins: BCAR1 (or p130Cas), NEDD9 (or HEF1), EFS (or SIN), and CASS4 (or HEPL). The FAT-like C-terminal domain of CAS proteins binds to the C-terminal domain of NSPs (novel SH2-containing proteins) to form multidomain signaling modules that mediate cell migration and invasion.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 221330702 693 DKKLVRYYAQQISTHMGNLMQAIDSFLETVEKNQPPKFFIAYGKFVVVSAHNLVTIGDNVYRNISKEALREKILRCTNAL 772
Cdd:cd11564    1 DRQLLLFYSEQCESHFGALQKAIDAFLSSVESNQPPKVFVAHSKFVILSAHKLVFIGDTLCRNVQSADVRNKVLRCSNQL 80

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|....*.
gi 221330702 773 SDALKTCVLKSKKAAAHFPSGSAVQEMVDSVVHINNLARDLKSVML 818
Cdd:cd11564   81 CEALKTVVLATKKAALQYPSVAAVQEMVDRVVELSHHAQQFKTSLG 126

C-terminal FAT-like Four helix bundle domain, also called DUF3513, of CAS (Crk-Associated Substrate) scaffolding protein, Neural precursor cell Expressed, Developmentally Down-regulated 9; a protein interaction module; NEDD9 is also called human enhancer of filamentation 1 (HEF1) or CAS-L (Crk-associated substrate in lymphocyte). It was first described as a gene predominantly expressed in early embryonic brain, and was also isolated from a screen of human proteins that regulate filamentous budding in yeast, and as a tyrosine phosphorylated protein in lymphocytes. It promotes metastasis in different solid tumors. NEDD9 localizes in focal adhesions and associates with FAK and Abl kinase. It also interacts with SMAD3 and the proteasomal machinery which allows its rapid turnover; these interactions are not shared by other CAS proteins. CAS proteins function as molecular scaffolds to regulate protein complexes that are involved in many cellular processes. They share a common domain structure containing protein interaction modules that enable their scaffolding function, including an N-terminal SH3 domain, an unstructured substrate domain that contains many YxxP motifs, a serine-rich four-helix bundle, and a FAT-like C-terminal domain, which binds to the C-terminal domain of NSPs (novel SH2-containing proteins) to form multidomain signaling modules that mediate cell migration and invasion.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 221330702 693 DKKLVRYYAQQISTHMGNLMQAIDSFLETVEKNQPPKFFIAYGKFVVVSAHNLVTIGDNVYRNISKEALREKILRCTNAL 772
Cdd:cd11570    1 DRQLLGFYADQCETHFISLLNAIDAFFSCVSSGQPPRIFVAHSKFVILSAHKLVFIGDTLTRQVTVQDIRNRVMNSSNQL 80

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|....*..
gi 221330702 773 SDALKTCVLKSKKAAAHFPSGSAVQEMVDSVVHINNLARDLKSVMLQ 819
Cdd:cd11570   81 CELLKTIVMATKMAALHYPSTAALQEMVDRVTDLSHLAQLFKLSLSQ 127

C-terminal FAT-like Four helix bundle domain, also called DUF3513, of CAS (Crk-Associated Substrate) scaffolding protein, Breast Cancer Anti-estrogen Resistance 1; a protein interaction module; BCAR1, also called p130cas or CASS1, is the founding member of the CAS family of scaffolding proteins and was originally identified through its ability to associate with Crk. The name BCAR1 was designated because the human gene was identified in a screen for genes that promote resistance to tamoxifen. It is widely expressed and its deletion is lethal in mice. It plays a role in regulating cell motility, survival, proliferation, transformation, cancer progression, and bacterial pathogenesis. CAS proteins function as molecular scaffolds to regulate protein complexes that are involved in many cellular processes. They share a common domain structure containing protein interaction modules that enable their scaffolding function, including an N-terminal SH3 domain, an unstructured substrate domain that contains many YxxP motifs, a serine-rich four-helix bundle, and a FAT-like C-terminal domain, which binds to the C-terminal domain of NSPs (novel SH2-containing proteins) to form multidomain signaling modules that mediate cell migration and invasion.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 221330702 693 DKKLVRYYAQQISTHMGNLMQAIDSFLETVEKNQPPKFFIAYGKFVVVSAHNLVTIGDNVYRNISKEALREKILRCTNAL 772
Cdd:cd11569    6 DRQLLLFYQEQCEANVTTLTNAIDAFFTSISSNQPPKIFVAHSKFVILSAHKLVFIGDTLSRQAKAADVRSKVTHYSNLL 85

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|....*..
gi 221330702 773 SDALKTCVLKSKKAAAHFPSGSAVQEMVDSVVHINNLARDLKSVMLQ 819
Cdd:cd11569   86 CEKLKEIVLSTKTAALQYPSPAAAKDMVERVKELGGSTQQFRMVLGQ 132

Src homology 3 domain of CAS (Crk-Associated Substrate) scaffolding protein family member, Neural precursor cell Expressed, Developmentally Down-regulated 9; NEDD9 is also called human enhancer of filamentation 1 (HEF1) or CAS-L (Crk-associated substrate in lymphocyte). It was first described as a gene predominantly expressed in early embryonic brain, and was also isolated from a screen of human proteins that regulate filamentous budding in yeast, and as a tyrosine phosphorylated protein in lymphocytes. It promotes metastasis in different solid tumors. NEDD9 localizes in focal adhesions and associates with FAK and Abl kinase. It also interacts with SMAD3 and the proteasomal machinery which allows its rapid turnover; these interactions are not shared by other CAS proteins. CAS proteins function as molecular scaffolds to regulate protein complexes that are involved in many cellular processes. They share a common domain structure that includes an N-terminal SH3 domain, an unstructured substrate domain that contains many YxxP motifs, a serine-rich four-helix bundle, and a FAT-like C-terminal domain. The SH3 domain of CAS proteins binds to diverse partners including FAK, FRNK, Pyk2, PTP-PEST, DOCK180, 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 221330702  82 AKAIYDNYADTSDELPFKKGDILTVLEQDTEGFQGWWLCSLRNRQGLCPGNRLRVL 137
Cdd:cd12002    2 ARALYDNVPECAEELAFRKGDILTVIEQNTGGLEGWWLCSLHGRQGIAPGNRLKLL 57

Src homology 3 domain of CAS (Crk-Associated Substrate) scaffolding protein family member 4; CASS4, also called HEPL (HEF1-EFS-p130Cas-like), localizes to focal adhesions and plays a role in regulating FAK activity, focal adhesion integrity, and cell spreading. It is most abundant in blood cells and lung tissue, and is also found in high levels in leukemia and ovarian cell lines. CAS proteins function as molecular scaffolds to regulate protein complexes that are involved in many cellular processes. They share a common domain structure that includes an N-terminal SH3 domain, an unstructured substrate domain that contains many YxxP motifs, a serine-rich four-helix bundle, and a FAT-like C-terminal domain. The SH3 domain of CAS proteins binds to diverse partners including FAK, FRNK, Pyk2, PTP-PEST, DOCK180, 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 221330702  80 LYAKAIYDNYADTSDELPFKKGDILTVLEQDTEGFQGWWLCSLRNRQGLCPGNRLRV 136
Cdd:cd12000    1 LLARALYDNKADCSDELAFRRGDILTVLEQNVPGSEGWWKCLLHGRQGLAPANRLQL 57

Src homology 3 domain of CAS (Crk-Associated Substrate) scaffolding protein family member, Embryonal Fyn-associated Substrate; EFS is also called HEFS, CASS3 (Cas scaffolding protein family member 3) or SIN (Src-interacting protein). It was identified based on interactions with the Src kinases, Fyn and Yes. It plays a role in thymocyte development and acts as a negative regulator of T cell proliferation. CAS proteins function as molecular scaffolds to regulate protein complexes that are involved in many cellular processes. They share a common domain structure that includes an N-terminal SH3 domain, an unstructured substrate domain that contains many YxxP motifs, a serine-rich four-helix bundle, and a FAT-like C-terminal domain. The SH3 domain of CAS proteins binds to diverse partners including FAK, FRNK, Pyk2, PTP-PEST, DOCK180, 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 221330702  82 AKAIYDNYADTSDELPFKKGDILTVLEQDTEGFQGWWLCSLRNRQGLCPGNRLRVL 137
Cdd:cd12003    3 AKALYDNAAESPEELSFRRGDVLMVLKREHGSLPGWWLCSLHGQQGIAPANRLRLL 58

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 221330702  81 YAKAIYDNYADTSDELPFKKGDILTVLEQDTEgfqGWWLCSLRN-RQGLCPGN 132
Cdd:cd00174    1 YARALYDYEAQDDDELSFKKGDIITVLEKDDD---GWWEGELNGgREGLFPAN 50

C-terminal FAT-like Four helix bundle domain, also called DUF3513, of CAS (Crk-Associated Substrate) scaffolding protein family member 4; a protein interaction module; CASS4, also called HEPL (HEF1-EFS-p130Cas-like), localizes to focal adhesions and plays a role in regulating FAK activity, focal adhesion integrity, and cell spreading. It is most abundant in blood cells and lung tissue, and is also found in high levels in leukemia and ovarian cell lines. CAS proteins function as molecular scaffolds to regulate protein complexes that are involved in many cellular processes. They share a common domain structure containing protein interaction modules that enable their scaffolding function, including an N-terminal SH3 domain, an unstructured substrate domain that contains many YxxP motifs, a serine-rich four-helix bundle, and a FAT-like C-terminal domain, which binds to the C-terminal domain of NSPs (novel SH2-containing proteins) to form multidomain signaling modules that mediate cell migration and invasion.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 221330702 709 GNLMQAIDSFLETVEKNQPPKFFIAYGKFVVVSAHNLVtigDNVYRNISKEALREKILRCTNALSDALKTCVLKSKKAAA 788
Cdd:cd11568   17 GALQKAISVFHSSLSSNQPPEVFISHSKLIIMVGQKLV---DTLCQEAKEREARNEILAGSSQLCALLKNLALATKNAAL 93

                         90
                 ....*....|....*
gi 221330702 789 HFPSGSAVQEMVDSV 803
Cdd:cd11568   94 QYPSPAALRELQDIA 108

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 221330702   83 KAIYDNYADTSDELPFKKGDILTVLEQDTEgfqGWWLC-SLRNRQGLCP 130
Cdd:pfam00018   1 VALYDYTAQEPDELSFKKGDIIIVLEKSED---GWWKGrNKGGKEGLIP 46

Src Homology 3 (SH3) domain of Inhibitor of ASPP protein (iASPP); iASPP, also called RelA-associated inhibitor (RAI), is an oncoprotein that inhibits the apoptotic transactivation potential of p53. It is upregulated in human breast cancers expressing wild-type p53, in acute leukemias regardless of the p53 mutation status, as well as in ovarian cancer where it is associated with poor patient outcome and chemoresistance. iASPP is also a binding partner and negative regulator of p65RelA, which promotes cell proliferation and inhibits apoptosis; p65RelA has the opposite effect on cell growth compared to the p53 family. It contains a proline-rich region, four ankyrin (ANK) repeats, and an SH3 domain at its C-terminal half. The SH3 domain and the ANK repeats of iASPP contribute to the p53 binding site; they bind to the DNA binding domain of p53. 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
                 ....*....|....*....|....*....|....*....|....*....
gi 221330702  84 AIYDNYADTSDELPFKKGDILTVLEQDTEGfQGWWLCSLRNRQGLCPGN 132
Cdd:cd11952    5 ALWDYSAEFPDELSFKEGDMVTVLRKDGEG-TDWWWASLCGREGYVPRN 52

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 221330702  83 KAIYDNYADTSDELPFKKGDILTVLEQDTEgfqGWWLCSLRNRQGLCPGN 132
Cdd:cd11823    3 KALYSYTANREDELSLQPGDIIEVHEKQDD---GWWLGELNGKKGIFPAT 49

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.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*.
gi 221330702  81 YAKAIYDNYADTSDELPFKKGDILTVLEQdTEGFQGWWLCSLRNRQGLCPGNRLRV 136
Cdd:cd11842    1 KAVALYDFAGEQPGDLAFQKGDIITILKK-SDSQNDWWTGRIGGREGIFPANYVEL 55

Src homology 3 domain of Protein kinase C and Casein kinase Substrate in Neurons (PACSIN) proteins; PACSINs, also called Synaptic dynamin-associated proteins (Syndapins), act as regulators of cytoskeletal and membrane dynamics. They bind both dynamin and Wiskott-Aldrich syndrome protein (WASP), and may provide direct links between the actin cytoskeletal machinery through WASP and dynamin-dependent endocytosis. Vetebrates harbor three isoforms with distinct expression patterns and specific functions. PACSINs contain 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 221330702  83 KAIYDNYADTSDELPFKKGDILTVLEQDTEgfQGWWLCSLRNRQGLCPGN 132
Cdd:cd11843    3 RALYDYEGQESDELSFKAGDILTKLEEEDE--QGWCKGRLDGRVGLYPAN 50

Src Homology 3 domain of Pak Interactive eXchange factors; PIX proteins are Rho guanine nucleotide exchange factors (GEFs), which activate small GTPases by exchanging bound GDP for free GTP. They act as GEFs for both Cdc42 and Rac 1, and have been implicated in cell motility, adhesion, neurite outgrowth, and cell polarity. Vertebrates contain two proteins from the PIX subfamily, alpha-PIX and beta-PIX. Alpha-PIX, also called ARHGEF6, is localized in dendritic spines where it regulates spine morphogenesis. Mutations in the ARHGEF6 gene cause X-linked intellectual disability in humans. Beta-PIX play 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 221330702  82 AKAIYDNYADTSDELPFKKGDILTVLEQdTEGfqGWWLCSLRNRQGLCPGN 132
Cdd:cd11877    2 VRAKFNFEGTNEDELSFDKGDIITVTQV-VEG--GWWEGTLNGKTGWFPSN 49

Src homology 3 domain of Proline-Serine-Threonine Phosphatase-Interacting Protein 1; PSTPIP1, also called CD2 Binding Protein 1 (CD2BP1), is mainly expressed in hematopoietic cells. It is a binding partner of the cell surface receptor CD2 and PTP-PEST, a tyrosine phosphatase which functions in cell motility and Rac1 regulation. It also plays a role in the activation of the Wiskott-Aldrich syndrome protein (WASP), which couples actin rearrangement and T cell activation. Mutations in the gene encoding PSTPIP1 cause the autoinflammatory disorder known as PAPA (pyogenic sterile arthritis, pyoderma gangrenosum, and acne) syndrome. PSTPIP1 contains an N-terminal F-BAR domain, PEST motifs, 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.

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gi 221330702  82 AKAIYDNYADTSDELPFKKGDILTVLEQDTEgfqGWWLCSLRNRQGLCPGNRL 134
Cdd:cd11824    2 YSVLYDYTAQEDDELSISKGDVVAVIEKGED---GWWTVERNGQKGLVPGTYL 51

Src Homology 3 (SH3) domain of Apoptosis Stimulating of p53 protein 2; ASPP2 is the full length form of the previously-identified tumor supressor, p53-binding protein 2 (p53BP2). ASPP2 activates the apoptotic function of the p53 family of tumor suppressors (p53, p63, and p73). It plays a central role in regulating apoptosis and cell growth; ASPP2-deficient mice show postnatal death. Downregulated expression of ASPP2 is frequently found in breast tumors, lung cancer, and diffuse large B-cell lymphoma where it is correlated with a poor clinical outcome. ASPP2 contains a proline-rich region, four ankyrin (ANK) repeats, and an SH3 domain at its C-terminal half. The SH3 domain and the ANK repeats of ASPP2 contribute to the p53 binding site; they bind to the DNA binding domain of p53. 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 221330702  84 AIYDNYADTSDELPFKKGDILTVLEQDTEGFQGWWLCSLRNRQGLCPGNRL 134
Cdd:cd11953    5 ALWDYEGESDDELSFKEGDCMTILRREDEDETEWWWARLNDKEGYVPRNLL 55

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 221330702  81 YAKAIYDNYADTSDELPFKKGDILTVLEQDtegFQGWWLCSLRNRQGLCPGN 132
Cdd:cd11805    1 RVQALYDFNPQEPGELEFRRGDIITVLDSS---DPDWWKGELRGRVGIFPAN 49

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 221330702  81 YAKAIYDNYADTSDELPFKKGDILTVLEQDTEgfqGWWLCSLRNRQGLCPGN 132
Cdd:cd11826    1 KVVALYDYTADKDDELSFQEGDIIYVTKKNDD---GWYEGVLNGVTGLFPGN 49

Third Src Homology 3 domain (SH3C) 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 third SH3 domain (SH3C) of CIN85. SH3C has 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.

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gi 221330702  81 YAKAIYDNYADTSDELPFKKGDILTVLEQDTEGfQGWWLCSLRNRQGLCPGNRLRVL 137
Cdd:cd12057    1 YCKVLFPYEAQNEDELTIKEGDIVTLISKDCID-AGWWEGELNGRRGVFPDNFVKLL 56

Second C-terminal Src homology 3 domain of Dynamin Binding Protein, also called Tuba, and similar domains; DNMBP or Tuba is a cdc42-specific guanine nucleotide exchange factor (GEF) that contains four N-terminal SH3 domains, a central RhoGEF [or Dbl homology (DH)] domain followed by a Bin/Amphiphysin/Rvs (BAR) domain, and two C-terminal SH3 domains. It provides a functional link between dynamin, Rho GTPase signaling, and actin dynamics. It plays an important role in regulating cell junction configuration. The C-terminal SH3 domains of DNMBP bind to N-WASP and Ena/VASP proteins, which are key regulatory proteins of the actin cytoskeleton. Also included in this subfamily is the second C-terminal SH3 domain of Rho guanine nucleotide exchange factor 37 (ARHGEF37), whose function is still 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 221330702  84 AIYDNYADTSDELPFKKGDILTVLE-QDTEGFQGWWLCSLRNRQGLCPGNRLR 135
Cdd:cd11800    4 ALYTFEARSPGELSVTEGQVVTVLEkHDLKGNPEWWLVEDRGKQGYVPSNYLA 56

Fourth Src homology 3 domain of ADAM-binding protein Eve-1; Eve-1, also called SH3 domain-containing protein 19 (SH3D19) or EEN-binding protein (EBP), exists in multiple alternatively spliced isoforms. The longest isoform contains five SH3 domain in the C-terminal region and seven proline-rich motifs in the N-terminal region. It is abundantly expressed in skeletal muscle and heart, and may be involved in regulating the activity of ADAMs (A disintegrin and metalloproteases). Eve-1 interacts with EEN, an endophilin involved in endocytosis and may be the target of the MLL-EEN fusion protein that is implicated in leukemogenesis. 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 221330702  81 YAKAIYDNYADTSDELPFKKGDILTVLEQ-DTEgfqgWWLCSLRNRQGLCPGN 132
Cdd:cd11817    1 WAVALYDFTGETEEDLSFQRGDRILVTEHlDAE----WSRGRLNGREGIFPRA 49

Src homology 3 domain of Apoptosis Stimulating of p53 proteins (ASPP); The ASPP family of proteins bind to important regulators of apoptosis (p53, Bcl-2, and RelA) and cell growth (APCL, PP1). They share similarity at their C-termini, where they harbor a proline-rich region, four ankyrin (ANK) repeats, and an SH3 domain. Vertebrates contain three members of the family: ASPP1, ASPP2, and iASPP. ASPP1 and ASPP2 activate the apoptotic function of the p53 family of tumor suppressors (p53, p63, and p73), while iASPP is an oncoprotein that specifically inhibits p53-induced apoptosis. The expression of ASPP proteins is altered in tumors; ASPP1 and ASPP2 are downregulated whereas iASPP is upregulated is some cancer types. ASPP proteins also bind and regulate protein phosphatase 1 (PP1), and this binding is competitive with p53 binding. The SH3 domain and the ANK repeats of ASPP contribute to the p53 binding site; they bind to the DNA binding domain of p53. 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 221330702  84 AIYDNYADTSDELPFKKGDILTVLEQDTEGFQGWWLCSLRNRQGLCPGNRL 134
Cdd:cd11807    5 ALFDYEAENGDELSFREGDELTVLRKGDDDETEWWWARLNDKEGYVPRNLL 55

Fifth Src homology 3 domain of ADAM-binding protein Eve-1; Eve-1, also called SH3 domain-containing protein 19 (SH3D19) or EEN-binding protein (EBP), exists in multiple alternatively spliced isoforms. The longest isoform contains five SH3 domain in the C-terminal region and seven proline-rich motifs in the N-terminal region. It is abundantly expressed in skeletal muscle and heart, and may be involved in regulating the activity of ADAMs (A disintegrin and metalloproteases). Eve-1 interacts with EEN, an endophilin involved in endocytosis and may be the target of the MLL-EEN fusion protein that is implicated in leukemogenesis. 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 221330702  82 AKAIYDNYADTSDELPFKKGDILTVLEQ-DTEGFQGwwlcSLRNRQGLCPGN 132
Cdd:cd11818    2 ARALYDFTGENEDELSFKAGDIITELESiDEEWMSG----ELRGKSGIFPKN 49

Src Homology 3 domain of Mixed Lineage Kinases; MLKs are Serine/Threonine Kinases (STKs), catalyzing the transfer of the gamma-phosphoryl group from ATP to S/T residues on protein substrates. MLKs act as mitogen-activated protein kinase kinase kinases (MAP3Ks, MKKKs, MAPKKKs), which phosphorylate and activate MAPK kinases (MAPKKs or MKKs or MAP2Ks), which in turn phosphorylate and activate MAPKs during signaling cascades that are important in mediating cellular responses to extracellular signals. MLKs play roles in immunity and inflammation, as well as in cell death, proliferation, and cell cycle regulation. Mammals have four MLKs (MLK1-4), mostly conserved in vertebrates, which contain an SH3 domain, a catalytic kinase domain, a leucine zipper, a proline-rich region, and a CRIB domain that mediates binding to GTP-bound Cdc42 and Rac. 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 221330702  84 AIYDNYADTSDELPFKKGDILTVLEQDTE--GFQGWWLCSLRNRQGLCPGN 132
Cdd:cd11876    4 ALFDYDARGEDELTLRRGQPVEVLSKDAAvsGDEGWWTGKIGDKVGIFPSN 54

N-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. Its N-terminal SH3 domain binds to Sos and Sos-derived proline-rich peptides. 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 221330702  82 AKAIYDNYADTSDELPFKKGDILTVLEQDTEgfQGWWLCSLRNRQGLCPGNRLRV 136
Cdd:cd11946    3 AIAKYDFKATADDELSFKRGDILKVLNEECD--QNWYKAELNGKDGFIPKNYIEM 55

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 221330702  82 AKAIYDNYADTSDELPFKKGDILTVLEQDTEgfqGWWLCSLRNRQGLCPGNRLR 135
Cdd:cd11950    2 VRALYDFEALEDDELGFNSGDVIEVLDSSNP---SWWKGRLHGKLGLFPANYVA 52

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 221330702  84 AIYDNYADTSDELPFKKGDILTVLEqDTEGfqGWWL-CSLR-NRQGLCPGN 132
Cdd:cd11845    4 ALYDYEARTDDDLSFKKGDRLQILD-DSDG--DWWLaRHLStGKEGYIPSN 51

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.

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gi 221330702  84 AIYDNYADTSDELPFKKGDILTVLEQDTegfQGWWLCSLRNRQGLCPGN 132
Cdd:cd11840    4 ALFPYTAQNEDELSFQKGDIINVLSKDD---PDWWRGELNGQTGLFPSN 49

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 221330702  82 AKAIYDNYADTSDELPFKKGDILTVLEQDTEgfqGWWLCSLRNRQGLCPGN 132
Cdd:cd11874    2 CKVLFSYTPQNEDELELKVGDTIEVLGEVEE---GWWEGKLNGKVGVFPSN 49