calponin homology (CH) domain found in 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. This model corresponds to the CH domain, an actin-binding domain which is present as a single copy in VAV1 protein.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 137483     2 ELWRQCTHWLIQCRVLPPSHRVTWEGAQVCELAQALRDGVLLCQLLNNLLPQAINLREVNLRPQMSQFLCLKNIRTFLST 81
Cdd:cd21262   1 ELWRQCAHWLIQCRVLPPNHRVTWDSAQVCDLAQALRDGVLLCQLLNNLLPHAVNLREINLRPQMSQFLCLKNIRTFLST 80

                        90       100       110       120
                ....*....|....*....|....*....|....*....|
gi 137483    82 CCEKFGLKRSELFEAFDLFDVQDFGKVIYTLSALSWTPIA 121
Cdd:cd21262  81 CCEKFGLRKSELFEAFDLFDVRDFGKVIDTLSILSWTPIA 120

Vav pleckstrin homology (PH) domain; Vav acts as a guanosine nucleotide exchange factor (GEF) for Rho/Rac proteins. They control processes including T cell activation, phagocytosis, and migration of cells. The Vav subgroup of Dbl GEFs consists of three family members (Vav1, Vav2, and Vav3) in mammals. Vav1 is preferentially expressed in the hematopoietic system, while Vav2 and Vav3 are described by broader expression patterns. Mammalian Vav proteins consist of a calponin homology (CH) domain, an acidic region, a catalytic Dbl homology (DH) domain, a PH domain, a zinc finger cysteine rich domain (C1/CRD), and an SH2 domain, flanked by two SH3 domains. In invertebrates such as Drosophila and C. elegans, Vav is missing the N-terminal SH3 domain. The DH domain is involved in RhoGTPase recognition and selectivity and stimulates the reorganization of the switch regions for GDP/GTP exchange. The PH domain is implicated in directing membrane localization, allosteric regulation of guanine nucleotide exchange activity, and as a phospholipid- dependent regulator of GEF activity. Vavs bind RhoGTPases including Rac1, RhoA, RhoG, and Cdc42, while other members of the GEF family are specific for a single RhoGTPase. This promiscuity is thought to be a result of its CRD. PH domains have diverse functions, but in general are involved in targeting proteins to the appropriate cellular location or in the interaction with a binding partner. They share little sequence conservation, but all have a common fold, which is electrostatically polarized. Less than 10% of PH domains bind phosphoinositide phosphates (PIPs) with high affinity and specificity. PH domains are distinguished from other PIP-binding domains by their specific high-affinity binding to PIPs with two vicinal phosphate groups: PtdIns(3,4)P2, PtdIns(4,5)P2 or PtdIns(3,4,5)P3 which results in targeting some PH domain proteins to the plasma membrane. A few display strong specificity in lipid binding. Any specificity is usually determined by loop regions or insertions in the N-terminus of the domain, which are not conserved across all PH domains. PH domains are found in cellular signaling proteins such as serine/threonine kinase, tyrosine kinases, regulators of G-proteins, endocytotic GTPases, adaptors, as well as cytoskeletal associated molecules and in lipid associated enzymes.polarized. PH domains also have diverse functions. They are often involved in targeting proteins to the plasma membrane, but only a few (less than 10%) display strong specificity in binding inositol phosphates. Any specificity is usually determined by loop regions or insertions in the N-terminus of the domain, which are not conserved across all PH domains. PH domains are found in cellular signaling proteins such as serine/threonine kinases, tyrosine kinases, regulators of G-proteins, endocytotic GTPases, adaptors, cytoskeletal associated molecules, and in lipid associated enzymes.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 137483   385 NFQLSIENLDQSLANYGRPKIDGELKITSVERRSKTDRYAFLLDKALLICKR-RGDSYDLKASVNLHSFQVRDDSSGE-- 461
Cdd:cd01223   1 SIQDLIENLNESLADYGRLQIDGELKIKSHEDQKKKDRYAFLFDKVLLICKSlRGDQYEYKEIINLSEYRIEDDPSRRtl 80

                        90       100       110       120
                ....*....|....*....|....*....|....*....|....*..
gi 137483   462 RDNKKWSHMFLLIEDQGAQGYELFFKTRELKKKWMEQFEMAISNIYP 508
Cdd:cd01223  81 KRDKRWSYQFLLVHKQGKTAYTLYAKTEELKKKWMEAIEMALSNIEP 127

protein kinase C conserved region 1 (C1 domain) found in VAV1 protein; VAV1 is expressed predominantly in the hematopoietic system and 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. This model corresponds to the C1 domain. The C1 domain is a cysteine-rich zinc binding domain that does not bind DNA nor possess structural similarity to conventional zinc finger domains; it contains two separate Zn(2+)-binding sites.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*..
gi 137483   510 NATANGHDFQMFSFEETTSCKACQMLLRGTFYQGYRCYRCRAPAHKECLGRVPPCGR 566
Cdd:cd20867   1 NATANGHDFQMFSFEETTSCKACQMLLRGTFYQGYRCHRCRAPAHKECLGRVPPCGR 57

First 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 first SH3 domain of Vav1 has been shown to bind the adaptor protein Grb2. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 137483   596 KMEVFQEYYGIPPPPGAFGPFLRLNPGDIVELTKAEAEHNWWEGRNTATNEVGWFPCNRVHPY 658
Cdd:cd11979   1 KMEVFQEYYGIPPPPGAFGPFLRLNPGDIVELTKAEAEQNWWEGRNTSTNEIGWFPCNRVKPY 63

calponin homology (CH) domain found in 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. This model corresponds to the CH domain, an actin-binding domain which is present as a single copy in VAV1 protein.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 137483     2 ELWRQCTHWLIQCRVLPPSHRVTWEGAQVCELAQALRDGVLLCQLLNNLLPQAINLREVNLRPQMSQFLCLKNIRTFLST 81
Cdd:cd21262   1 ELWRQCAHWLIQCRVLPPNHRVTWDSAQVCDLAQALRDGVLLCQLLNNLLPHAVNLREINLRPQMSQFLCLKNIRTFLST 80

                        90       100       110       120
                ....*....|....*....|....*....|....*....|
gi 137483    82 CCEKFGLKRSELFEAFDLFDVQDFGKVIYTLSALSWTPIA 121
Cdd:cd21262  81 CCEKFGLRKSELFEAFDLFDVRDFGKVIDTLSILSWTPIA 120

Vav pleckstrin homology (PH) domain; Vav acts as a guanosine nucleotide exchange factor (GEF) for Rho/Rac proteins. They control processes including T cell activation, phagocytosis, and migration of cells. The Vav subgroup of Dbl GEFs consists of three family members (Vav1, Vav2, and Vav3) in mammals. Vav1 is preferentially expressed in the hematopoietic system, while Vav2 and Vav3 are described by broader expression patterns. Mammalian Vav proteins consist of a calponin homology (CH) domain, an acidic region, a catalytic Dbl homology (DH) domain, a PH domain, a zinc finger cysteine rich domain (C1/CRD), and an SH2 domain, flanked by two SH3 domains. In invertebrates such as Drosophila and C. elegans, Vav is missing the N-terminal SH3 domain. The DH domain is involved in RhoGTPase recognition and selectivity and stimulates the reorganization of the switch regions for GDP/GTP exchange. The PH domain is implicated in directing membrane localization, allosteric regulation of guanine nucleotide exchange activity, and as a phospholipid- dependent regulator of GEF activity. Vavs bind RhoGTPases including Rac1, RhoA, RhoG, and Cdc42, while other members of the GEF family are specific for a single RhoGTPase. This promiscuity is thought to be a result of its CRD. PH domains have diverse functions, but in general are involved in targeting proteins to the appropriate cellular location or in the interaction with a binding partner. They share little sequence conservation, but all have a common fold, which is electrostatically polarized. Less than 10% of PH domains bind phosphoinositide phosphates (PIPs) with high affinity and specificity. PH domains are distinguished from other PIP-binding domains by their specific high-affinity binding to PIPs with two vicinal phosphate groups: PtdIns(3,4)P2, PtdIns(4,5)P2 or PtdIns(3,4,5)P3 which results in targeting some PH domain proteins to the plasma membrane. A few display strong specificity in lipid binding. Any specificity is usually determined by loop regions or insertions in the N-terminus of the domain, which are not conserved across all PH domains. PH domains are found in cellular signaling proteins such as serine/threonine kinase, tyrosine kinases, regulators of G-proteins, endocytotic GTPases, adaptors, as well as cytoskeletal associated molecules and in lipid associated enzymes.polarized. PH domains also have diverse functions. They are often involved in targeting proteins to the plasma membrane, but only a few (less than 10%) display strong specificity in binding inositol phosphates. Any specificity is usually determined by loop regions or insertions in the N-terminus of the domain, which are not conserved across all PH domains. PH domains are found in cellular signaling proteins such as serine/threonine kinases, tyrosine kinases, regulators of G-proteins, endocytotic GTPases, adaptors, cytoskeletal associated molecules, and in lipid associated enzymes.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 137483   385 NFQLSIENLDQSLANYGRPKIDGELKITSVERRSKTDRYAFLLDKALLICKR-RGDSYDLKASVNLHSFQVRDDSSGE-- 461
Cdd:cd01223   1 SIQDLIENLNESLADYGRLQIDGELKIKSHEDQKKKDRYAFLFDKVLLICKSlRGDQYEYKEIINLSEYRIEDDPSRRtl 80

                        90       100       110       120
                ....*....|....*....|....*....|....*....|....*..
gi 137483   462 RDNKKWSHMFLLIEDQGAQGYELFFKTRELKKKWMEQFEMAISNIYP 508
Cdd:cd01223  81 KRDKRWSYQFLLVHKQGKTAYTLYAKTEELKKKWMEAIEMALSNIEP 127

Guanine nucleotide exchange factor for Rho/Rac/Cdc42-like GTPases; Guanine nucleotide exchange factor for Rho/Rac/Cdc42-like GTPases Also called Dbl-homologous (DH) domain. It appears that PH domains invariably occur C-terminal to RhoGEF/DH domains. Improved coverage.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 137483      198 CLREIQQTEEKYTDTLGSIQQHFMKPLQR---FLKPQDMETIFVNIEELFSVHTHFLKELKDALA--GPGATTLYQVFIK 272
Cdd:smart00325   1 VLKELLQTERNYVRDLKLLVEVFLKPLKKelkLLSPNELETLFGNIEEIYEFHRDFLDELEERIEewDDSVERIGDVFLK 80

                           90       100       110       120       130       140       150       160
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 137483      273 YKERFLVYGRYCSQVESASKHLDQVATaREDVQMKLEECSQRANNGRFTLRDLLMVPMQRVLKYHLLLQELVKHTQ-DAT 351
Cdd:smart00325  81 LEEFFKIYSEYCSNHPDALELLKKLKK-NPRFQKFLKEIESSPQCRRLTLESLLLKPVQRLTKYPLLLKELLKHTPeDHE 159

                          170       180
                   ....*....|....*....|.
gi 137483      352 EKENLRLALDAMRDLAQCVNE 372
Cdd:smart00325 160 DREDLKKALKAIKELANQVNE 180

protein kinase C conserved region 1 (C1 domain) found in VAV1 protein; VAV1 is expressed predominantly in the hematopoietic system and 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. This model corresponds to the C1 domain. The C1 domain is a cysteine-rich zinc binding domain that does not bind DNA nor possess structural similarity to conventional zinc finger domains; it contains two separate Zn(2+)-binding sites.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*..
gi 137483   510 NATANGHDFQMFSFEETTSCKACQMLLRGTFYQGYRCYRCRAPAHKECLGRVPPCGR 566
Cdd:cd20867   1 NATANGHDFQMFSFEETTSCKACQMLLRGTFYQGYRCHRCRAPAHKECLGRVPPCGR 57

First 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 first SH3 domain of Vav1 has been shown to bind the adaptor protein Grb2. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 137483   596 KMEVFQEYYGIPPPPGAFGPFLRLNPGDIVELTKAEAEHNWWEGRNTATNEVGWFPCNRVHPY 658
Cdd:cd11979   1 KMEVFQEYYGIPPPPGAFGPFLRLNPGDIVELTKAEAEQNWWEGRNTSTNEIGWFPCNRVKPY 63

SH2 domain;

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 137483     671 WYAGPMERAGAEGILTNR-SDGTYLVRQRVKDTAEFAISIKYNVEVKHIKIMTSE-GLYRITEKKAFRGLLELVEFY 745
Cdd:pfam00017   1 WYHGKISRQEAERLLLNGkPDGTFLVRESESTPGGYTLSVRDDGKVKHYKIQSTDnGGYYISGGVKFSSLAELVEHY 77

CAMSAP CH domain; This domain is the N-terminal CH domain from the CAMSAP proteins.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 137483      18 PPSHRVTWEGAQVCELAQALRDGVLLCQLLNNLLPQAINLREVNLRPQMSQFLCLKNIRTFLSTCCEKFGLKRSELfEAF 97
Cdd:pfam11971   1 PLSQRSLPLSPPVEDLLRDLSDGCALAALIHFYCPQLIDLEDICLKESMSLADSLYNIQLLQEFCQRHLGNRCCHL-TLE 79

                  ....*
gi 137483      98 DLFDV 102
Cdd:pfam11971  80 DLLYA 84

PH domain; PH stands for pleckstrin homology.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 137483     403 PKIDGEL-KITSVERRSKTDRYAFLLDKALLICK--RRGDSYDLKASVNLHSFQVRDDSSGERDNKKWSHMFLLIEDQGA 479
Cdd:pfam00169   1 VVKEGWLlKKGGGKKKSWKKRYFVLFDGSLLYYKddKSGKSKEPKGSISLSGCEVVEVVASDSPKRKFCFELRTGERTGK 80

                          90       100
                  ....*....|....*....|....*
gi 137483     480 QGYELFFKTRELKKKWMEQFEMAIS 504
Cdd:pfam00169  81 RTYLLQAESEEERKDWIKAIQSAIR 105

Pleckstrin homology domain; Domain commonly found in eukaryotic signalling proteins. The domain family possesses multiple functions including the abilities to bind inositol phosphates, and various proteins. PH domains have been found to possess inserted domains (such as in PLC gamma, syntrophins) and to be inserted within other domains. Mutations in Brutons tyrosine kinase (Btk) within its PH domain cause X-linked agammaglobulinaemia (XLA) in patients. Point mutations cluster into the positively charged end of the molecule around the predicted binding site for phosphatidylinositol lipids.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 137483      403 PKIDGEL-KITSVERRSKTDRYAFLLDKALLICKRRGD--SYDLKASVNLHSFQVRDDSSGERDNKKwsHMFLLIEDQGA 479
Cdd:smart00233   1 VIKEGWLyKKSGGGKKSWKKRYFVLFNSTLLYYKSKKDkkSYKPKGSIDLSGCTVREAPDPDSSKKP--HCFEIKTSDRK 78

                           90       100
                   ....*....|....*....|....*
gi 137483      480 QgYELFFKTRELKKKWMEQFEMAIS 504
Cdd:smart00233  79 T-LLLQAESEEEREKWVEALRKAIA 102

RhoGEF, Guanine nucleotide exchange factor for Rho/Rac/Cdc42-like GTPases [Signal transduction mechanisms];

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 137483    194 KRCCCLREIQQTEEKYTDTLGSIQQHFMKPLQRF------LKPQDMETIFVNIEELFSVHTHFLKELKD----ALAGPGA 263
Cdd:COG5422  484 KRQEAIYEVIYTERDFVKDLEYLRDTWIKPLEESniipenARRNFIKHVFANINEIYAVNSKLLKALTNrqclSPIVNGI 563

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 137483    264 TTLYQVFIKYKERFLVYG------RYCSQVESASKHldqvATAREDVQMKLEECSQRANngrftLRDLLMVPMQRVLKYH 337
Cdd:COG5422  564 ADIFLDYVPKFEPFIKYGasqpyaKYEFEREKSVNP----NFARFDHEVERLDESRKLE-----LDGYLTKPTTRLARYP 634

                        170       180       190       200       210       220       230       240
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 137483    338 LLLQELVKHT-QDATEKENLRLALDAMRDL----------AQCVNEVKRDNETLrqitnfQLSIENLDQSLANYGRPKI- 405
Cdd:COG5422  635 LLLEEVLKFTdPDNPDTEDIPKVIDMLREFlsrlnfesgkAENRGDLFHLNQQL------LFKPEYVNLGLNDEYRKIIf 708

                        250       260       270       280       290       300
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 137483    406 DGELKITSVERRSKT---DRYAFLLDKALLICK------RRGDSYDLKASVNLHSFQVRDDSSGER 462
Cdd:COG5422  709 KGVLKRKAKSKTDGSlrgDIQFFLLDNMLLFCKakavnkWRQHKVFQRPIPLELLFISPDEDSPDR 774

Calponin homology domain; Actin binding domains present in duplicate at the N-termini of spectrin-like proteins (including dystrophin, alpha-actinin). These domains cross-link actin filaments into bundles and networks. A calponin homology domain is predicted in yeasst Cdc24p.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 137483       32 ELAQALRDGVLLCQLLNNLLPQAINLREVNlrPQMSQFLCLKNIRTFLStCCEKFGLKRsELFEAFDLFDVQ-DFGKVIY 110
Cdd:smart00033  21 NFSSDLKDGVALCALLNSLSPGLVDKKKVA--ASLSRFKKIENINLALS-FAEKLGGKV-VLFEPEDLVEGPkLILGVIW 96

                   ....*
gi 137483      111 TLSAL 115
Cdd:smart00033  97 TLISL 101

calponin homology (CH) domain found in 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. This model corresponds to the CH domain, an actin-binding domain which is present as a single copy in VAV1 protein.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 137483     2 ELWRQCTHWLIQCRVLPPSHRVTWEGAQVCELAQALRDGVLLCQLLNNLLPQAINLREVNLRPQMSQFLCLKNIRTFLST 81
Cdd:cd21262   1 ELWRQCAHWLIQCRVLPPNHRVTWDSAQVCDLAQALRDGVLLCQLLNNLLPHAVNLREINLRPQMSQFLCLKNIRTFLST 80

                        90       100       110       120
                ....*....|....*....|....*....|....*....|
gi 137483    82 CCEKFGLKRSELFEAFDLFDVQDFGKVIYTLSALSWTPIA 121
Cdd:cd21262  81 CCEKFGLRKSELFEAFDLFDVRDFGKVIDTLSILSWTPIA 120

Vav pleckstrin homology (PH) domain; Vav acts as a guanosine nucleotide exchange factor (GEF) for Rho/Rac proteins. They control processes including T cell activation, phagocytosis, and migration of cells. The Vav subgroup of Dbl GEFs consists of three family members (Vav1, Vav2, and Vav3) in mammals. Vav1 is preferentially expressed in the hematopoietic system, while Vav2 and Vav3 are described by broader expression patterns. Mammalian Vav proteins consist of a calponin homology (CH) domain, an acidic region, a catalytic Dbl homology (DH) domain, a PH domain, a zinc finger cysteine rich domain (C1/CRD), and an SH2 domain, flanked by two SH3 domains. In invertebrates such as Drosophila and C. elegans, Vav is missing the N-terminal SH3 domain. The DH domain is involved in RhoGTPase recognition and selectivity and stimulates the reorganization of the switch regions for GDP/GTP exchange. The PH domain is implicated in directing membrane localization, allosteric regulation of guanine nucleotide exchange activity, and as a phospholipid- dependent regulator of GEF activity. Vavs bind RhoGTPases including Rac1, RhoA, RhoG, and Cdc42, while other members of the GEF family are specific for a single RhoGTPase. This promiscuity is thought to be a result of its CRD. PH domains have diverse functions, but in general are involved in targeting proteins to the appropriate cellular location or in the interaction with a binding partner. They share little sequence conservation, but all have a common fold, which is electrostatically polarized. Less than 10% of PH domains bind phosphoinositide phosphates (PIPs) with high affinity and specificity. PH domains are distinguished from other PIP-binding domains by their specific high-affinity binding to PIPs with two vicinal phosphate groups: PtdIns(3,4)P2, PtdIns(4,5)P2 or PtdIns(3,4,5)P3 which results in targeting some PH domain proteins to the plasma membrane. A few display strong specificity in lipid binding. Any specificity is usually determined by loop regions or insertions in the N-terminus of the domain, which are not conserved across all PH domains. PH domains are found in cellular signaling proteins such as serine/threonine kinase, tyrosine kinases, regulators of G-proteins, endocytotic GTPases, adaptors, as well as cytoskeletal associated molecules and in lipid associated enzymes.polarized. PH domains also have diverse functions. They are often involved in targeting proteins to the plasma membrane, but only a few (less than 10%) display strong specificity in binding inositol phosphates. Any specificity is usually determined by loop regions or insertions in the N-terminus of the domain, which are not conserved across all PH domains. PH domains are found in cellular signaling proteins such as serine/threonine kinases, tyrosine kinases, regulators of G-proteins, endocytotic GTPases, adaptors, cytoskeletal associated molecules, and in lipid associated enzymes.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 137483   385 NFQLSIENLDQSLANYGRPKIDGELKITSVERRSKTDRYAFLLDKALLICKR-RGDSYDLKASVNLHSFQVRDDSSGE-- 461
Cdd:cd01223   1 SIQDLIENLNESLADYGRLQIDGELKIKSHEDQKKKDRYAFLFDKVLLICKSlRGDQYEYKEIINLSEYRIEDDPSRRtl 80

                        90       100       110       120
                ....*....|....*....|....*....|....*....|....*..
gi 137483   462 RDNKKWSHMFLLIEDQGAQGYELFFKTRELKKKWMEQFEMAISNIYP 508
Cdd:cd01223  81 KRDKRWSYQFLLVHKQGKTAYTLYAKTEELKKKWMEAIEMALSNIEP 127

calponin homology (CH) domain found in VAV proteins; VAV proteins function both as cytoplasmic guanine nucleotide exchange factors (GEFs) for Rho GTPases and as scaffold proteins, and they play important roles in cell signaling by coupling cell surface receptors to various effector functions. They play key roles in processes that require cytoskeletal reorganization including immune synapse formation, phagocytosis, cell spreading, and platelet aggregation, among others. Vertebrates have three VAV proteins (VAV1, VAV2, and VAV3). 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. This model corresponds to the CH domain, an actin-binding domain which is present as a single copy in VAV proteins.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 137483     2 ELWRQCTHWLIQCRVLPPSHRVTWEGAQVCELAQALRDGVLLCQLLNNLLPQAINLREVNLRPQMSQFLCLKNIRTFLST 81
Cdd:cd21201   1 ELWRQCADWLIRCGVLPPDHRATQPNATVFDLAQALRDGVLLCQLLNRLSPGSVDDREINLRPQMSQFLCLKNIRTFLQA 80

                        90       100       110
                ....*....|....*....|....*....|....*..
gi 137483    82 CCEKFGLKRSELFEAFDLFDVQDFGKVIYTLSALSWT 118
Cdd:cd21201  81 CRTVFGLRSADLFEPEDLYDVTNFGKVIRTLSKLSHT 117

Guanine nucleotide exchange factor for Rho/Rac/Cdc42-like GTPases; Also called Dbl-homologous (DH) domain. It appears that PH domains invariably occur C-terminal to RhoGEF/DH domains.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 137483   195 RCCCLREIQQTEEKYTDTLGSIQQHFMKPLQRFLK---PQDMETIFVNIEELFSVHTHFLKELKDALAGPGATT--LYQV 269
Cdd:cd00160   1 RQEVIKELLQTERNYVRDLKLLVEVFLKPLDKELLplsPEEVELLFGNIEEIYEFHRIFLKSLEERVEEWDKSGprIGDV 80

                        90       100       110       120       130       140       150       160
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 137483   270 FIKYKERFLVYGRYCSQVESASKHLDQvataREDVQMKLEECSQRANN--GRFTLRDLLMVPMQRVLKYHLLLQELVKHT 347
Cdd:cd00160  81 FLKLAPFFKIYSEYCSNHPDALELLKK----LKKFNKFFQEFLEKAESecGRLKLESLLLKPVQRLTKYPLLLKELLKHT 156

                       170       180
                ....*....|....*....|....*
gi 137483   348 QDAT-EKENLRLALDAMRDLAQCVN 371
Cdd:cd00160 157 PDGHeDREDLKKALEAIKEVASQVN 181

calponin homology (CH) domain found in VAV2 protein and similar proteins; VAV2 is widely expressed and functions as a guanine nucleotide exchange factor (GEF) for RhoA, RhoB and RhoG and also activates Rac1 and Cdc42. It is implicated in many cellular and physiological functions including blood pressure control, eye development, neurite outgrowth and branching, EGFR endocytosis and degradation, and cell cluster morphology, among others. It has been reported to associate with Nek3. 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 model corresponds to CH domain, an actin-binding domain which is present as a single copy in VAV2 protein.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 137483     2 ELWRQCTHWLIQCRVLPPSHRVTWEGAQVCELAQALRDGVLLCQLLNNLLPQAINLREVNLRPQMSQFLCLKNIRTFLST 81
Cdd:cd21263   1 EEWRQCGRWLIDCKVLPPNHRVVWPSAVVFDLAQALRDGVLLCQLLHNLSPGSIDLKDINFRPQMSQFLCLKNIRTFLKV 80

                        90       100       110
                ....*....|....*....|....*....|....*....
gi 137483    82 CCEKFGLKRSELFEAFDLFDVQDFGKVIYTLSALSWTPI 120
Cdd:cd21263  81 CHDKFGLRNSELFDPFDLFDVRDFGKVISALSRLSHHSI 119

Src homology 2 (SH2) domain found in the Vav3 proteins; Proto-oncogene vav is a member of the Dbl family of guanine nucleotide exchange factors (GEF) for the Rho family of GTP binding proteins. All vavs are activated by tyrosine phosphorylation leading to their activation. There are three Vav mammalian family members: Vav1 which is expressed in the hematopoietic system, and Vav2 and Vav3 are more ubiquitously expressed. Vav3 preferentially activates RhoA, RhoG and, to a lesser extent, Rac1. Alternatively spliced transcript variants encoding different isoforms have been described for this gene. VAV3 has been shown to interact with Grb2. Vav proteins are involved in several processes that require cytoskeletal reorganization, such as the formation of the immunological synapse (IS), phagocytosis, platelet aggregation, spreading, and transformation. Vavs function as guanine nucleotide exchange factors (GEFs) for the Rho/Rac family of GTPases. Vav family members have several conserved motifs/domains including: a leucine-rich region, a leucine-zipper, a calponin homology (CH) domain, an acidic domain, a Dbl-homology (DH) domain, a pleckstrin homology (PH) domain, a cysteine-rich domain, 2 SH3 domains, a proline-rich region, and a SH2 domain. Vavs are the only known Rho GEFs that have both the DH/PH motifs and SH2/SH3 domains in the same protein. The leucine-rich helix-loop-helix (HLH) domain is thought to be involved in protein heterodimerization with other HLH proteins and it may function as a negative regulator by forming inactive heterodimers. The CH domain is usually involved in the association with filamentous actin, but in Vav it controls NFAT stimulation, Ca2+ mobilization, and its transforming activity. Acidic domains are involved in protein-protein interactions and contain regulatory tyrosines. The DH domain is a GDP-GTP exchange factor on Rho/Rac GTPases. The PH domain in involved in interactions with GTP-binding proteins, lipids and/or phosphorylated serine/threonine residues. The SH3 domain is involved in localization of proteins to specific sites within the cell interacting with protein with proline-rich sequences. The SH2 domain mediates a high affinity interaction with tyrosine phosphorylated proteins. In general SH2 domains are involved in signal transduction. They typically bind pTyr-containing ligands via two surface pockets, a pTyr and hydrophobic binding pocket, allowing proteins with SH2 domains to localize to tyrosine phosphorylated sites.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 137483   665 DLSVHLWYAGPMERAGAEGILTNRSDGTYLVRQRVKDTAEFAISIKYNVEVKHIKIMTSEGLYRITEKKAFRGLLELVEF 744
Cdd:cd10407   1 DYSCQPWYAGAMERLQAETELINRVNSTYLVRHRTKESGEYAISIKYNNEVKHIKILTRDGFFHIAENRKFKSLMELVEY 80

                        90       100
                ....*....|....*....|...
gi 137483   745 YQQNSLKDCFKSLDTTLQFPYKE 767
Cdd:cd10407  81 YKHHSLKEGFRSLDTTLQFPYKE 103

Src homology 2 (SH2) domain found in the Vav2 proteins; Proto-oncogene vav is a member of the Dbl family of guanine nucleotide exchange factors (GEF) for the Rho family of GTP binding proteins. All vavs are activated by tyrosine phosphorylation leading to their activation. There are three Vav mammalian family members: Vav1 which is expressed in the hematopoietic system, and Vav2 and Vav3 are more ubiquitously expressed. Vav2 is a GEF for RhoA, RhoB and RhoG and may activate Rac1 and Cdc42. Vav2 has been shown to interact with CD19 and Grb2. Alternatively spliced transcript variants encoding different isoforms have been found for Vav2. Vav proteins are involved in several processes that require cytoskeletal reorganization, such as the formation of the immunological synapse (IS), phagocytosis, platelet aggregation, spreading, and transformation. Vavs function as guanine nucleotide exchange factors (GEFs) for the Rho/Rac family of GTPases. Vav family members have several conserved motifs/domains including: a leucine-rich region, a leucine-zipper, a calponin homology (CH) domain, an acidic domain, a Dbl-homology (DH) domain, a pleckstrin homology (PH) domain, a cysteine-rich domain, 2 SH3 domains, a proline-rich region, and a SH2 domain. Vavs are the only known Rho GEFs that have both the DH/PH motifs and SH2/SH3 domains in the same protein. The leucine-rich helix-loop-helix (HLH) domain is thought to be involved in protein heterodimerization with other HLH proteins and it may function as a negative regulator by forming inactive heterodimers. The CH domain is usually involved in the association with filamentous actin, but in Vav it controls NFAT stimulation, Ca2+ mobilization, and its transforming activity. Acidic domains are involved in protein-protein interactions and contain regulatory tyrosines. The DH domain is a GDP-GTP exchange factor on Rho/Rac GTPases. The PH domain in involved in interactions with GTP-binding proteins, lipids and/or phosphorylated serine/threonine residues. The SH3 domain is involved in localization of proteins to specific sites within the cell interacting with protein with proline-rich sequences. The SH2 domain mediates a high affinity interaction with tyrosine phosphorylated proteins. In general SH2 domains are involved in signal transduction. They typically bind pTyr-containing ligands via two surface pockets, a pTyr and hydrophobic binding pocket, allowing proteins with SH2 domains to localize to tyrosine phosphorylated sites.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 137483   665 DLSVHLWYAGPMERAGAEGILTNRSDGTYLVRQRVKDTAEFAISIKYNVEVKHIKIMTSEGLYRITEKKAFRGLLELVEF 744
Cdd:cd10406   1 DYTAYPWFAGNMERQQTDNLLKSHASGTYLIRERPAEAERFAISIKFNDEVKHIKVVEKDNWIHITEAKKFESLLELVEY 80

                        90       100
                ....*....|....*....|..
gi 137483   745 YQQNSLKDCFKSLDTTLQFPYK 766
Cdd:cd10406  81 YQCHSLKESFKQLDTTLKYPYK 102

First 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 first SH3 domain of Vav1 has been shown to bind the adaptor protein Grb2. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 137483   596 KMEVFQEYYGIPPPPGAFGPFLRLNPGDIVELTKAEAEHNWWEGRNTATNEVGWFPCNRVHPY 658
Cdd:cd11979   1 KMEVFQEYYGIPPPPGAFGPFLRLNPGDIVELTKAEAEQNWWEGRNTSTNEIGWFPCNRVKPY 63

protein kinase C conserved region 1 (C1 domain) found in VAV3 protein; VAV3 is ubiquitously expressed and functions as a phosphorylation-dependent guanine nucleotide exchange factor (GEF) for RhoA, RhoG, and Rac1. Its function has been implicated in the hematopoietic, bone, cerebellar, and cardiovascular systems. VAV3 is essential in axon guidance in neurons that control blood pressure and respiration. It is overexpressed in prostate cancer cells and plays a role in regulating androgen receptor transcriptional activity. 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. This model corresponds to the C1 domain. The C1 domain is a cysteine-rich zinc binding domain that does not bind DNA nor possess structural similarity to conventional zinc finger domains; it contains two separate Zn(2+)-binding sites.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*....
gi 137483   508 PENATANGHDFQMFSFEETTSCKACQMLLRGTFYQGYRCYRCRAPAHKECLGRVPPCGR 566
Cdd:cd20869   1 PDNATSNSHDFKMHTFERVTSCKVCQMLLRGTFYQGYLCSKCGAGAHKECLGRLDSCGR 59

protein kinase C conserved region 1 (C1 domain) found in VAV2 protein; VAV2 is widely expressed and functions as a guanine nucleotide exchange factor (GEF) for RhoA, RhoB and RhoG and also activates Rac1 and Cdc42. It is implicated in many cellular and physiological functions including blood pressure control, eye development, neurite outgrowth and branching, EGFR endocytosis and degradation, and cell cluster morphology, among others. It has been reported to associate with Nek3. 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. This model corresponds to the C1 domain. The C1 domain is a cysteine-rich zinc binding domain that does not bind DNA nor possess structural similarity to conventional zinc finger domains; it contains two separate Zn(2+)-binding sites.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 137483   511 ATANGHDFQMFSFEETTSCKACQMLLRGTFYQGYRCYRCRAPAHKECLGRVPPC 564
Cdd:cd20868   1 ATANHHNFQMYTFDKTTNCKACKMLLRGTFYQGYYCSKCGAGAHKECLEVIPPC 54

protein kinase C conserved region 1 (C1 domain) found in VAV proteins; VAV proteins function both as cytoplasmic guanine nucleotide exchange factors (GEFs) for Rho GTPases and as scaffold proteins, and they play important roles in cell signaling by coupling cell surface receptors to various effector functions. They play key roles in processes that require cytoskeletal reorganization including immune synapse formation, phagocytosis, cell spreading, and platelet aggregation, among others. Vertebrates have three VAV proteins (VAV1, VAV2, and VAV3). 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. This model corresponds to the C1 domain. The C1 domain is a cysteine-rich zinc binding domain that does not bind DNA nor possess structural similarity to conventional zinc finger domains; it contains two separate Zn(2+)-binding sites.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 137483   514 NGHDFQMFSFEETTSCKACQMLLRGTFYQGYRCYRCRAPAHKECLGRVPPCG 565
Cdd:cd20810   1 TGHSFELTTFKEPTTCSVCKKLLKGLFFQGYKCSVCGAAVHKECIAKVKRCG 52

Src homology 2 domains; Src homology 2 domains bind phosphotyrosine-containing polypeptides via 2 surface pockets. Specificity is provided via interaction with residues that are distinct from the phosphotyrosine. Only a single occurrence of a SH2 domain has been found in S. cerevisiae.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 137483      669 HLWYAGPMERAGAEGILTNRSDGTYLVRQRVKDTAEFAISIKYNVEVKHIKIM-TSEGLYRITEKKAFRGLLELVEFYQQ 747
Cdd:smart00252   1 QPWYHGFISREEAEKLLKNEGDGDFLVRDSESSPGDYVLSVRVKGKVKHYRIRrNEDGKFYLEGGRKFPSLVELVEHYQK 80

                   ...
gi 137483      748 NSL 750
Cdd:smart00252  81 NSL 83

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 137483      785 GTAKARYDFCARDRSELSLKEGDIIKILNKKGqQGWWRGEI-YGRIGWFPSNYVE 838
Cdd:smart00326   3 PQVRALYDYTAQDPDELSFKKGDIITVLEKSD-DGWWKGRLgRGKEGLFPSNYVE 56

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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 137483   786 TAKARYDFCARDRSELSLKEGDIIKIlNKKGQQGWWRGEIYGRIGWFPSNYVEE 839
Cdd:cd11877   1 LVRAKFNFEGTNEDELSFDKGDIITV-TQVVEGGWWEGTLNGKTGWFPSNYVKE 53

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 137483   788 KARYDFCARDRSELSLKEGDIIKIlNKKGQQGWWRGEIYGRIGWFPSNYVEE 839
Cdd:cd11823   3 KALYSYTANREDELSLQPGDIIEV-HEKQDDGWWLGELNGKKGIFPATYVEE 53

Src Homology 3 domain of fungal peroxisomal membrane protein Pex13p; Pex13p, located in the peroxisomal membrane, contains two transmembrane regions and a C-terminal SH3 domain. It binds to the peroxisomal targeting type I (PTS1) receptor Pex5p and the docking factor Pex14p through its SH3 domain. It is essential for both PTS1 and PTS2 protein import pathways into the peroxisomal matrix. Pex13p binds Pex14p, which contains a PxxP motif, in a classical fashion to the proline-rich ligand binding site of its SH3 domain. It binds the WxxxF/Y motif of Pex5p in a novel site that does not compete with Pex14p binding. 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 137483   787 AKARYDFCARDRS-ELSLKEGDIIKILNKKGQQG----WWRGEIY-GRIGWFPSNYVEE 839
Cdd:cd11771   2 CRALYDFTPENPEmELSLKKGDIVAVLSKTDPLGrdseWWKGRTRdGRIGWFPSNYVEV 60

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 137483     788 KARYDFCARDRSELSLKEGDIIKILNKKGqQGWWRGE-IYGRIGWFPS 834
Cdd:pfam00018   1 VALYDYTAQEPDELSFKKGDIIIVLEKSE-DGWWKGRnKGGKEGLIPS 47

C-terminal Src homology 3 domain of GRB2-related adaptor protein; GRAP is a GRB-2 like adaptor protein that is highly expressed in lymphoid tissues. It acts as a negative regulator of T cell receptor (TCR)-induced lymphocyte proliferation by downregulating the signaling to the Ras/ERK pathway. It has been identified as a regulator of TGFbeta signaling in diabetic kidney tubules and may have a role in the pathogenesis of the disease. GRAP contains an N-terminal SH3 domain, a central SH2 domain, and a C-terminal SH3 domain. The C-terminal SH3 domains (SH3c) of the related proteins, 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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|.
gi 137483   787 AKARYDFCARDRSELSLKEGDIIKILNKKgQQGWWRGEIYGRIGWFPSNYV 837
Cdd:cd11951   2 VQAQYDFSAEDPSQLSFRRGDIIEVLDCP-DPNWWRGRISGRVGFFPRNYV 51

Second Src Homology 3 domain of FCH and double SH3 domains proteins; This group is composed of FCH and double SH3 domains protein 1 (FCHSD1) and FCHSD2. These proteins have a common domain structure consisting of an N-terminal F-BAR (FES-CIP4 Homology and Bin/Amphiphysin/Rvs), two SH3, and C-terminal proline-rich domains. They have only been characterized in silico and their functions remain unknown. This group also includes the insect protein, nervous wreck, which acts as a regulator of synaptic growth signaling. 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 137483   787 AKARYDFCARDRSELSLKEGDIIKILNKKGQQ---GWWRGEIYGRIGWFPSNYVEE 839
Cdd:cd11762   2 VRALYDYEAQSDEELSFPEGAIIRILRKDDNGvddGWWEGEFNGRVGVFPSLVVEE 57

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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 137483   787 AKARYDFCARDRSELSLKEGDIIKILNKKGQQgWWRGEIYGRIGWFPSNYVEE 839
Cdd:cd11805   2 VQALYDFNPQEPGELEFRRGDIITVLDSSDPD-WWKGELRGRVGIFPANYVQP 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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 137483   788 KARYDFCARDRSELSLKEGDIIKI-LNKKGQQGWWRGEIYGRIGWFPSNYVE 838
Cdd:cd11836   3 RALYAFEARNPDEISFQPGDIIQVdESQVAEPGWLAGELKGKTGWFPANYVE 54