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 530425424 385 NFQLSIENLDQSLAHYGRPKIDGELKITSVERRSKMDRYAFLLDKALLICKR-RGDSYDLKDFVNLHSFQVRDDSSG--D 461
Cdd:cd01223    1 SIQDLIENLNESLADYGRLQIDGELKIKSHEDQKKKDRYAFLFDKVLLICKSlRGDQYEYKEIINLSEYRIEDDPSRrtL 80

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|....*..
gi 530425424 462 RDNKKWSHMFLLIEDQGAQGYELFFKTRELKKKWMEQFEMAISNIYP 508
Cdd:cd01223   81 KRDKRWSYQFLLVHKQGKTAYTLYAKTEELKKKWMEAIEMALSNIEP 127

Src homology 2 (SH2) domain; In general, SH2 domains are involved in signal transduction; they bind pTyr-containing polypeptide ligands via two surface pockets, a pTyr and hydrophobic binding pocket, allowing proteins with SH2 domains to localize to tyrosine phosphorylated sites. They are present in a wide array of proteins including: adaptor proteins (Nck1, Crk, Grb2), scaffolds (Slp76, Shc, Dapp1), kinases (Src, Syk, Fps, Tec), phosphatases (Shp-1, Shp-2), transcription factors (STAT1), Ras signaling molecules (Ras-Gap), ubiquitination factors (c-Cbl), cytoskeleton regulators (Tensin), signal regulators (SAP), and phospholipid second messengers (PLCgamma), amongst others.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 530425424 665 DLSVHLWYAGPMERAGAESILANRSDGTFLVRQRVKDAAEFAISIKYNVEVKHIKIMTAEGLYRITEKKAFRGLT 739
Cdd:cd10405    1 DLSVHLWYAGPMERAGAESILANRSDGTYLVRQRVKDAAEFAISIKYNVEVKHIKIMTAEGLYRITEKKAFRGLT 75

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 530425424 510 NATANGHDFQMFSFEETTSCKACQMLLRGTFYQGYRCHRCRASAHKECLGRVPPCGR 566
Cdd:cd20867    1 NATANGHDFQMFSFEETTSCKACQMLLRGTFYQGYRCHRCRAPAHKECLGRVPPCGR 57

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 530425424 385 NFQLSIENLDQSLAHYGRPKIDGELKITSVERRSKMDRYAFLLDKALLICKR-RGDSYDLKDFVNLHSFQVRDDSSG--D 461
Cdd:cd01223    1 SIQDLIENLNESLADYGRLQIDGELKIKSHEDQKKKDRYAFLFDKVLLICKSlRGDQYEYKEIINLSEYRIEDDPSRrtL 80

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|....*..
gi 530425424 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 530425424   198 CLREIQQTEEKYTDTLGSIQQHFLKPLQR---FLKPQDIEIIFINIEDLLRVHTHFLKEMKEALGT--PGAANLYQVFIK 272
Cdd:smart00325   1 VLKELLQTERNYVRDLKLLVEVFLKPLKKelkLLSPNELETLFGNIEEIYEFHRDFLDELEERIEEwdDSVERIGDVFLK 80

                           90       100       110       120       130       140       150       160
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 530425424   273 YKERFLVYGRYCSQVESASKHLDRvAAAREDVQMKLEECSQRANNGRFTLRDLLMVPMQRVLKYHLLLQELVKHTQEAM- 351
Cdd:smart00325  81 LEEFFKIYSEYCSNHPDALELLKK-LKKNPRFQKFLKEIESSPQCRRLTLESLLLKPVQRLTKYPLLLKELLKHTPEDHe 159

                          170       180
                   ....*....|....*....|.
gi 530425424   352 EKENLRLALDAMRDLAQCVNE 372
Cdd:smart00325 160 DREDLKKALKAIKELANQVNE 180

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 530425424 596 KMEVFQEYYGLPPPPGAIGPFLRLNPGDIVELTKAEAEQNWWEGRNTSTNEIGWFPCNRVKPY 658
Cdd:cd11979    1 KMEVFQEYYGIPPPPGAFGPFLRLNPGDIVELTKAEAEQNWWEGRNTSTNEIGWFPCNRVKPY 63

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 530425424 510 NATANGHDFQMFSFEETTSCKACQMLLRGTFYQGYRCHRCRASAHKECLGRVPPCGR 566
Cdd:cd20867    1 NATANGHDFQMFSFEETTSCKACQMLLRGTFYQGYRCHRCRAPAHKECLGRVPPCGR 57

SH2 domain;

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 530425424  671 WYAGPMERAGAESILANR-SDGTFLVRQRVKDAAEFAISIKYNVEVKHIKIM-TAEGLYRITEKKAFRGL 738
Cdd:pfam00017   1 WYHGKISRQEAERLLLNGkPDGTFLVRESESTPGGYTLSVRDDGKVKHYKIQsTDNGGYYISGGVKFSSL 70

Phorbol esters/diacylglycerol binding domain (C1 domain); This domain is also known as the Protein kinase C conserved region 1 (C1) domain.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 530425424  516 HDFQMFSFEETTSCKACQMLLRGTFYQGYRCHRCRASAHKECLGRVPP-CGRH 567
Cdd:pfam00130   1 HHFVHRNFKQPTFCDHCGEFLWGLGKQGLKCSWCKLNVHKRCHEKVPPeCGCD 53

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 530425424   403 PKIDGEL-KITSVERRSKMDRYAFLLDKALLICKRRGD--SYDLKDFVNLHSFQVRDdsSGDRDNKKWSHMFLLIEDQGA 479
Cdd:smart00233   1 VIKEGWLyKKSGGGKKSWKKRYFVLFNSTLLYYKSKKDkkSYKPKGSIDLSGCTVRE--APDPDSSKKPHCFEIKTSDRK 78

                           90       100
                   ....*....|....*....|....*
gi 530425424   480 QgYELFFKTRELKKKWMEQFEMAIS 504
Cdd:smart00233  79 T-LLLQAESEEEREKWVEALRKAIA 102

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
                   ....*....|....*....|....*....|....*....|
gi 530425424   617 LRLNPGDIVELTKaEAEQNWWEGRNtSTNEIGWFPCNRVK 656
Cdd:smart00326  19 LSFKKGDIITVLE-KSDDGWWKGRL-GRGKEGLFPSNYVE 56

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

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 530425424  194 KRCCCLREIQQTEEKYTDTLGSIQQHFLKPLQRF-LKPQDIEIIFI-----NIEDLLRVHTHFLKEMKE----ALGTPGA 263
Cdd:COG5422   484 KRQEAIYEVIYTERDFVKDLEYLRDTWIKPLEESnIIPENARRNFIkhvfaNINEIYAVNSKLLKALTNrqclSPIVNGI 563

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 530425424  264 ANLYQVFIKYKERFLVYG------RYCSQVESASKHldrvAAAREDVQMKLEECSQRANngrftLRDLLMVPMQRVLKYH 337
Cdd:COG5422   564 ADIFLDYVPKFEPFIKYGasqpyaKYEFEREKSVNP----NFARFDHEVERLDESRKLE-----LDGYLTKPTTRLARYP 634

                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 530425424  338 LLLQELVKHTQEAM-EKENLRLALDAMRDL----------AQCVNEVKRDNETLrqitnfQLSIENLDQSLAHYGRPKI- 405
Cdd:COG5422   635 LLLEEVLKFTDPDNpDTEDIPKVIDMLREFlsrlnfesgkAENRGDLFHLNQQL------LFKPEYVNLGLNDEYRKIIf 708

                         250       260       270       280       290       300
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 530425424  406 DGELKITSVERRS---KMDRYAFLLDKALLICK------RRGDSYDLKDFVNLHSFQVRDDSSGDR 462
Cdd:COG5422   709 KGVLKRKAKSKTDgslRGDIQFFLLDNMLLFCKakavnkWRQHKVFQRPIPLELLFISPDEDSPDR 774

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 530425424 385 NFQLSIENLDQSLAHYGRPKIDGELKITSVERRSKMDRYAFLLDKALLICKR-RGDSYDLKDFVNLHSFQVRDDSSG--D 461
Cdd:cd01223    1 SIQDLIENLNESLADYGRLQIDGELKIKSHEDQKKKDRYAFLFDKVLLICKSlRGDQYEYKEIINLSEYRIEDDPSRrtL 80

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|....*..
gi 530425424 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 530425424   2 ELWRQCTHWLIQCRVLPPSHRVTWDGAQVCELAQALRDGVLLCQLLNNLLPHAINLREVNLRPQMSQFLCLKNIRTFLST 81
Cdd:cd21201    1 ELWRQCADWLIRCGVLPPDHRATQPNATVFDLAQALRDGVLLCQLLNRLSPGSVDDREINLRPQMSQFLCLKNIRTFLQA 80

                         90       100       110
                 ....*....|....*....|....*....|....*..
gi 530425424  82 CCEKFGLKRSELFEAFDLFDVQDFGKVIYTLSALSWT 118
Cdd:cd21201   81 CRTVFGLRSADLFEPEDLYDVTNFGKVIRTLSKLSHT 117

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 530425424   198 CLREIQQTEEKYTDTLGSIQQHFLKPLQR---FLKPQDIEIIFINIEDLLRVHTHFLKEMKEALGT--PGAANLYQVFIK 272
Cdd:smart00325   1 VLKELLQTERNYVRDLKLLVEVFLKPLKKelkLLSPNELETLFGNIEEIYEFHRDFLDELEERIEEwdDSVERIGDVFLK 80

                           90       100       110       120       130       140       150       160
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 530425424   273 YKERFLVYGRYCSQVESASKHLDRvAAAREDVQMKLEECSQRANNGRFTLRDLLMVPMQRVLKYHLLLQELVKHTQEAM- 351
Cdd:smart00325  81 LEEFFKIYSEYCSNHPDALELLKK-LKKNPRFQKFLKEIESSPQCRRLTLESLLLKPVQRLTKYPLLLKELLKHTPEDHe 159

                          170       180
                   ....*....|....*....|.
gi 530425424   352 EKENLRLALDAMRDLAQCVNE 372
Cdd:smart00325 160 DREDLKKALKAIKELANQVNE 180

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 530425424 596 KMEVFQEYYGLPPPPGAIGPFLRLNPGDIVELTKAEAEQNWWEGRNTSTNEIGWFPCNRVKPY 658
Cdd:cd11979    1 KMEVFQEYYGIPPPPGAFGPFLRLNPGDIVELTKAEAEQNWWEGRNTSTNEIGWFPCNRVKPY 63

RhoGEF domain; Guanine nucleotide exchange factor for Rho/Rac/Cdc42-like GTPases Also called Dbl-homologous (DH) domain. It appears that pfam00169 domains invariably occur C-terminal to RhoGEF/DH domains.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 530425424  198 CLREIQQTEEKYTDTLGSIQQHFLKPLQRFLK--PQDIEIIFINIEDLLRVHTHFLKEMKEALGtPGAANLYQVFIKYKE 275
Cdd:pfam00621   1 VIKELLQTERSYVRDLEILVEVFLPPNSKPLSesEEEIKTIFSNIEEIYELHRQLLLEELLKEW-ISIQRIGDIFLKFAP 79

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 530425424  276 RFLVYGRYCSQVESASKHLDRVAAAREDVQMKLEECSQRANNGRFTLRDLLMVPMQRVLKYHLLLQELVKHTQEA-MEKE 354
Cdd:pfam00621  80 GFKVYSTYCSNYPKALKLLKKLLKKNPKFRAFLEELEANPECRGLDLNSFLIKPVQRIPRYPLLLKELLKHTPPDhPDYE 159

                         170
                  ....*....|....*..
gi 530425424  355 NLRLALDAMRDLAQCVN 371
Cdd:pfam00621 160 DLKKALEAIKEVAKQIN 176

First Src homology 3 domain of VAV proteins; VAV proteins function both as cytoplasmic guanine nucleotide exchange factors (GEFs) for Rho GTPases and 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. The SH3 domain of VAV is involved in the localization of proteins to specific sites within the cell, by interacting with proline-rich sequences within target proteins. 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 530425424 596 KMEVFQEYYGLPPPPGAIGPFLRLNPGDIVELTKAEAEQNWWEGRNTSTNEIGWFPCNRVKP 657
Cdd:cd11831    1 KMVVMQNYHGNPPPPGAGGPVLTLQTGDVVELLKGDAESPWWEGRNVATREVGYFPSSSVKP 62

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 530425424 508 PENATANGHDFQMFSFEETTSCKACQMLLRGTFYQGYRCHRCRASAHKECLGRVPPCGR 566
Cdd:cd20869    1 PDNATSNSHDFKMHTFERVTSCKVCQMLLRGTFYQGYLCSKCGAGAHKECLGRLDSCGR 59

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 530425424 514 NGHDFQMFSFEETTSCKACQMLLRGTFYQGYRCHRCRASAHKECLGRVPPCG 565
Cdd:cd20810    1 TGHSFELTTFKEPTTCSVCKKLLKGLFFQGYKCSVCGAAVHKECIAKVKRCG 52

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
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 530425424 665 DLSVHLWYAGPMERAGAESILANRSDGTFLVRQRVKDAAEFAISIKYNVEVKHIKIMTAEGLYRITEKKAFRGL 738
Cdd:cd10406    1 DYTAYPWFAGNMERQQTDNLLKSHASGTYLIRERPAEAERFAISIKFNDEVKHIKVVEKDNWIHITEAKKFESL 74

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
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 530425424   669 HLWYAGPMERAGAESILANRSDGTFLVRQRVKDAAEFAISIKYNVEVKHIKIM-TAEGLYRITEKKAFRGLT 739
Cdd:smart00252   1 QPWYHGFISREEAEKLLKNEGDGDFLVRDSESSPGDYVLSVRVKGKVKHYRIRrNEDGKFYLEGGRKFPSLV 72

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

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 530425424   18 PPSHRVTWDGAQVCELAQALRDGVLLCQLLNNLLPHAINLREVNLRPQMSQFLCLKNIRTFLSTCCEKFGLKRSELfEAF 97
Cdd:pfam11971   1 PLSQRSLPLSPPVEDLLRDLSDGCALAALIHFYCPQLIDLEDICLKESMSLADSLYNIQLLQEFCQRHLGNRCCHL-TLE 79

                  ....*
gi 530425424   98 DLFDV 102
Cdd:pfam11971  80 DLLYA 84

First Src homology 3 domain of 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. The SH3 domain of VAV is involved in the localization of proteins to specific sites within the cell, by interacting with proline-rich sequences within target proteins. 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 530425424 596 KMEVFQEYYGLPPPPGAigPFLRLNPGDIVELTKAEAEQNWWEGRNTSTNEIGWFPCNRVKP 657
Cdd:cd11980    1 KMVAVQNYHGNPAPPGK--PVLTFQTGDVIELLRGDPDSPWWEGRLLQTKKSGYFPSSSVKP 60

Calponin homology (CH) domain; The CH domain is found in both cytoskeletal proteins and signal transduction proteins. The CH domain is involved in actin binding in some members of the family. However in calponins there is evidence that the CH domain is not involved in its actin binding activity. Most member proteins have from two to four copies of the CH domain, however some proteins such as calponin have only a single copy.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 530425424    1 MELWRQCTHWLIQCRVLPPSHRvtwdgaQVCELAQALRDGVLLCQLLNNLLPHAINLREVNLRPqmsqFLCLKNIRTFLS 80
Cdd:pfam00307   1 LELEKELLRWINSHLAEYGPGV------RVTNFTTDLRDGLALCALLNKLAPGLVDKKKLNKSE----FDKLENINLALD 70

                          90       100       110
                  ....*....|....*....|....*....|....*...
gi 530425424   81 TCCEKFGLKRSELfEAFDLFDVQDFgKVIYTLSALSWT 118
Cdd:pfam00307  71 VAEKKLGVPKVLI-EPEDLVEGDNK-SVLTYLASLFRR 106

protein kinase C conserved region 1 (C1 domain) superfamily; 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 the motif HX12CX2CXnCX2CX4HX2CX7C, where C and H are cysteine and histidine, respectively; X represents other residues; and n is either 13 or 14. C1 has a globular fold with two separate Zn(2+)-binding sites. It was originally discovered as lipid-binding modules in protein kinase C (PKC) isoforms. C1 domains that bind and respond to phorbol esters (PE) and diacylglycerol (DAG) are referred to as typical, and those that do not respond to PE and DAG are deemed atypical. A C1 domain may also be referred to as PKC or non-PKC C1, based on the parent protein's activity. Most C1 domain-containing non-PKC proteins act as lipid kinases and scaffolds, except PKD which acts as a protein kinase. PKC C1 domains play roles in membrane translocation and activation of the enzyme.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|
gi 530425424 516 HDFQMFSFEETTSCKACQMLLRGTFYQGYRCHRCRASAHKECLGRVP-PC 564
Cdd:cd00029    1 HRFVPTTFSSPTFCDVCGKLIWGLFKQGLKCSDCGLVCHKKCLDKAPsPC 50

calponin homology (CH) domain superfamily; CH domains are actin filament (F-actin) binding motifs, which may be present as a single copy or in tandem repeats (which increase binding affinity). They either function as autonomous actin binding motifs or serve a regulatory function. CH domains are found in cytoskeletal and signal transduction proteins, including actin-binding proteins like spectrin, alpha-actinin, dystrophin, utrophin, and fimbrin, as well as proteins essential for regulation of cell shape (cortexillins), and signaling proteins (Vav).

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 530425424   5 RQCTHWLiqCRVLPPShrvtwDGAQVCELAQALRDGVLLCQLLNNLLPHAINLREvnlRPQMSQFLCLKNIRTFLSTcCE 84
Cdd:cd00014    2 EELLKWI--NEVLGEE-----LPVSITDLFESLRDGVLLCKLINKLSPGSIPKIN---KKPKSPFKKRENINLFLNA-CK 70

                         90       100       110
                 ....*....|....*....|....*....|...
gi 530425424  85 KFGLKRSELFEAFDLFDVQDFGKVIYTLSALSW 117
Cdd:cd00014   71 KLGLPELDLFEPEDLYEKGNLKKVLGTLWALAL 103

second protein kinase C conserved region 1 (C1 domain) found in protein kinase D2 (PKD2) and similar proteins; PKD2, also called PRKD2, HSPC187, or serine/threonine-protein kinase D2 (nPKC-D2), is a serine/threonine-protein kinase that converts transient diacylglycerol (DAG) signals into prolonged physiological effects downstream of PKC, and is involved in the regulation of cell proliferation via MAPK1/3 (ERK1/2) signaling, oxidative stress-induced NF-kappa-B activation, inhibition of HDAC7 transcriptional repression, signaling downstream of T-cell antigen receptor (TCR) and cytokine production, and plays a role in Golgi membrane trafficking, angiogenesis, secretory granule release and cell adhesion. PKD2 contains N-terminal tandem cysteine-rich zinc binding C1 (PKC conserved region 1), central PH (Pleckstrin Homology), and C-terminal catalytic kinase domains. This model corresponds to the second 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
                 ....*....|....*....|....*....|....*....|....*..
gi 530425424 516 HDFQMFSFEETTSCKACQMLLRGTFYQGYRCHRCRASAHKECLGRVP 562
Cdd:cd20843   12 HTFVIHSYTRPTVCQFCKKLLKGLFRQGLQCKDCKFNCHKRCATRVP 58

second protein kinase C conserved region 1 (C1 domain) found in the family of protein kinase D (PKD); PKDs are important regulators of many intracellular signaling pathways such as ERK and JNK, and cellular processes including the organization of the trans-Golgi network, membrane trafficking, cell proliferation, migration, and apoptosis. They are activated in a PKC-dependent manner by many agents including diacylglycerol (DAG), PDGF, neuropeptides, oxidative stress, and tumor-promoting phorbol esters, among others. Mammals harbor three types of PKDs: PKD1 (or PKCmu), PKD2, and PKD3 (or PKCnu). PKDs contain N-terminal tandem cysteine-rich zinc binding C1 (PKC conserved region 1), central PH (Pleckstrin Homology), and C-terminal catalytic kinase domains. This model corresponds to the second 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
                 ....*....|....*....|....*....|....*....|....*..
gi 530425424 516 HDFQMFSFEETTSCKACQMLLRGTFYQGYRCHRCRASAHKECLGRVP 562
Cdd:cd20796    2 HTFVVHTYTKPTVCQHCKKLLKGLFRQGLQCKDCKFNCHKKCAEKVP 48

protein kinase C conserved region 1 (C1 domain) found in uncharacterized Rho guanine nucleotide exchange factor (ARHGEF)-like proteins; The family includes a group of uncharacterized proteins that show high sequence similarity to vertebrate Rho guanine nucleotide exchange factors ARHGEF11 and ARHGEF12, which may play a role in the regulation of RhoA GTPase by guanine nucleotide-binding alpha-12 (GNA12) and alpha-13 (GNA13). Unlike typical ARHGEF11 and ARHGEF12, members of this family contain a C1 domain. 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
                 ....*....|....*....|....*....|....*....|....
gi 530425424 515 GHDFQMFSFEETTSCKACQMLLRGTFYQGYRCHRCRASAHKECL 558
Cdd:cd20832    1 GHQFVLQHYYQVTFCNHCSGLLWGIGYQGYQCSDCEFNIHKQCI 44

Protein kinase C conserved region 1 (C1) domains (Cysteine-rich domains); Some bind phorbol esters and diacylglycerol. Some bind RasGTP. Zinc-binding domains.

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|
gi 530425424   516 HDFQMFSFEETTSCKACQMLLRGTFYQGYRCHRCRASAHKECLGRVP-PC 564
Cdd:smart00109   1 HKHVFRTFTKPTFCCVCRKSIWGSFKQGLRCSECKVKCHKKCADKVPkAC 50

Src homology 2 (SH2) domain found in suppressor of cytokine signaling (SOCS) proteins; SH2 domain found in SOCS proteins. SOCS was first recognized as a group of cytokine-inducible SH2 (CIS) domain proteins comprising eight family members in human (CIS and SOCS1-SOCS7). In addition to the SH2 domain, SOCS proteins have a variable N-terminal domain and a conserved SOCS box in the C-terminal domain. SOCS proteins bind to a substrate via their SH2 domain. The prototypical members, CIS and SOCS1-SOCS3, have been shown to regulate growth hormone signaling in vitro and in a classic negative feedback response compete for binding at phosphotyrosine sites in JAK kinase and receptor pathways to displace effector proteins and target bound receptors for proteasomal degradation. Loss of SOCS activity results in excessive cytokine signaling associated with a variety of hematopoietic, autoimmune, and inflammatory diseases and certain cancers. Members (SOCS4-SOCS7) were identified by their conserved SOCS box, an adapter motif of 3 helices that associates substrate binding domains, such as the SOCS SH2 domain, ankryin, and WD40 with ubiquitin ligase components. These show limited cytokine induction. 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
                 ....*....|....*....|....*....|....*....|....*....|
gi 530425424 671 WYAGPMERAGAESILANRSDGTFLVRQRVKDAAEFAISIKYNVEVKHIKI 720
Cdd:cd10388   12 WYWGPMSWEDAEKVLSNKPDGSFLVRDSSDDRYIFSLSFRSQGSVHHTRI 61

C-terminal Src homology 2 (C-SH2) domain found in SH2 domain Phosphatases (SHP) proteins; The SH2 domain phosphatases (SHP-1, SHP-2/Syp, Drosophila corkscrew (csw), and Caenorhabditis elegans Protein Tyrosine Phosphatase (Ptp-2)) are cytoplasmic signaling enzymes. They are both targeted and regulated by interactions of their SH2 domains with phosphotyrosine docking sites. These proteins contain two SH2 domains (N-SH2, C-SH2) followed by a tyrosine phosphatase (PTP) domain, and a C-terminal extension. Shp1 and Shp2 have two tyrosyl phosphorylation sites in their C-tails, which are phosphorylated differentially by receptor and nonreceptor PTKs. Csw retains the proximal tyrosine and Ptp-2 lacks both sites. Shp-binding proteins include receptors, scaffolding adapters, and inhibitory receptors. Some of these bind both Shp1 and Shp2 while others bind only one. Most proteins that bind a Shp SH2 domain contain one or more immuno-receptor tyrosine-based inhibitory motifs (ITIMs): [SIVL]xpYxx[IVL]. Shp1 N-SH2 domain blocks the catalytic domain and keeps the enzyme in the inactive conformation, and is thus believed to regulate the phosphatase activity of SHP-1. Its C-SH2 domain is thought to be involved in searching for phosphotyrosine activators. The SHP2 N-SH2 domain is a conformational switch; it either binds and inhibits the phosphatase, or it binds phosphoproteins and activates the enzyme. The C-SH2 domain contributes binding energy and specificity, but it does not have a direct role in activation. Csw SH2 domain function is essential, but either SH2 domain can fulfill this requirement. The role of the csw SH2 domains during Sevenless receptor tyrosine kinase (SEV) signaling is to bind Daughter of Sevenless rather than activated SEV. Ptp-2 acts in oocytes downstream of sheath/oocyte gap junctions to promote major sperm protein (MSP)-induced MAP Kinase (MPK-1) phosphorylation. Ptp-2 functions in the oocyte cytoplasm, not at the cell surface to inhibit multiple RasGAPs, resulting in sustained Ras activation. It is thought that MSP triggers PTP-2/Ras activation and ROS production to stimulate MPK-1 activity essential for oocyte maturation and that secreted MSP domains and Cu/Zn superoxide dismutases function antagonistically to control ROS and MAPK signaling. 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
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 530425424 671 WYAGPMERAGAESILANR-SDGTFLVRQRVKDAAEFAISIKYN-VEVKHIKIMTAEGLYRITEKKAFRGLT 739
Cdd:cd09931    2 WFHGHLSGKEAEKLLLEKgKPGSFLVRESQSKPGDFVLSVRTDdDKVTHIMIRCQGGKYDVGGGEEFDSLT 72