Src homology 2 (SH2) domain found in the growth factor receptor bound, subclass 7 (Grb7) proteins; The Grb family binds to the epidermal growth factor receptor (EGFR, erbB1) via their SH2 domains. Grb7 is part of the Grb7 family of proteins which also includes Grb10, and Grb14. They are composed of an N-terminal Proline-rich domain, a Ras Associating-like (RA) domain, a Pleckstrin Homology (PH) domain, a phosphotyrosine interaction region (PIR, BPS) and a C-terminal SH2 domain. The SH2 domains of Grb7, Grb10 and Grb14 preferentially bind to a different RTK. Grb7 binds strongly to the erbB2 receptor, unlike Grb10 and Grb14 which bind weakly to it. Grb7 family proteins are phosphorylated on serine/threonine as well as tyrosine residues. 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 1033408890 445 IHRTQPWFHGHISREDTQRLIIQQGLVDGVFLVRDSQRNPKGFVLSLCHLQKVKHYLILPIEEDGRPYYTMDDGQTRFTD 524
Cdd:cd10413     1 IHRTQPWFHGRISREESQRLIGQQGLVDGVFLVRESQRNPQGFVLSLCHLQKVKHYLILPSEEEGRLYFSMDDGQTRFTD 80

                          90       100
                  ....*....|....*....|....*...
gi 1033408890 525 LIQLVEFHQINRGILPCKLKHYCTSVAL 552
Cdd:cd10413    81 LLQLVEFHQLNRGILPCLLRHCCTRVAL 108

Ras-associating (RA) domain found in growth factor receptor-bound (Grb) protein 7; GRB7, also termed B47, or epidermal growth factor receptor GRB-7, or GRB7 adapter protein, is a signal-transducing cytoplasmic adaptor protein that is co-opted by numerous tyrosine kinases involved in various cellular signaling and functions. Grb7 and its related family members Grb10 and Grb14 share a conserved domain architecture that includes an amino-terminal proline-rich region, a central segment termed the GM region (for Grb and Mig) which includes the RA, PIR, and pleckstrin homology (PH) domains, and a carboxyl-terminal SH2 domain. The tandem RA and PH domains of Grb7/10/14 are also found in a second adaptor family, Rap1-interacting adaptor molecule (RIAM) and lamellipodin, which is involved in actin-cytoskeleton rearrangement. Grb7/10/14 family proteins are phosphorylated on serine/threonine as well as tyrosine residues and are mainly localized to the cytoplasm. Grb7 could interact with activated N-Ras in transfected cells.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1033408890 119 GSHVVKVYSEDGTCRSLEVTAGTTARHVCEMLVQKTQALHDDCWSLVEVYQHLALERYLEDHESVVEVQATWPVGGDSRF 198
Cdd:cd16140     1 GPHVVKVYSEDGTCRSLEVTAGATARHVCEMLVQRAHCLDDESWSLVELHPHLALERCLEDHESVVEVQATWPAGGDSRF 80

                  ....*...
gi 1033408890 199 VFRKNYAK 206
Cdd:cd16140    81 VFRKNFAK 88

Src homology 2 (SH2) domain found in the growth factor receptor bound, subclass 7 (Grb7) proteins; The Grb family binds to the epidermal growth factor receptor (EGFR, erbB1) via their SH2 domains. Grb7 is part of the Grb7 family of proteins which also includes Grb10, and Grb14. They are composed of an N-terminal Proline-rich domain, a Ras Associating-like (RA) domain, a Pleckstrin Homology (PH) domain, a phosphotyrosine interaction region (PIR, BPS) and a C-terminal SH2 domain. The SH2 domains of Grb7, Grb10 and Grb14 preferentially bind to a different RTK. Grb7 binds strongly to the erbB2 receptor, unlike Grb10 and Grb14 which bind weakly to it. Grb7 family proteins are phosphorylated on serine/threonine as well as tyrosine residues. 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 1033408890 445 IHRTQPWFHGHISREDTQRLIIQQGLVDGVFLVRDSQRNPKGFVLSLCHLQKVKHYLILPIEEDGRPYYTMDDGQTRFTD 524
Cdd:cd10413     1 IHRTQPWFHGRISREESQRLIGQQGLVDGVFLVRESQRNPQGFVLSLCHLQKVKHYLILPSEEEGRLYFSMDDGQTRFTD 80

                          90       100
                  ....*....|....*....|....*...
gi 1033408890 525 LIQLVEFHQINRGILPCKLKHYCTSVAL 552
Cdd:cd10413    81 LLQLVEFHQLNRGILPCLLRHCCTRVAL 108

Ras-associating (RA) domain found in growth factor receptor-bound (Grb) protein 7; GRB7, also termed B47, or epidermal growth factor receptor GRB-7, or GRB7 adapter protein, is a signal-transducing cytoplasmic adaptor protein that is co-opted by numerous tyrosine kinases involved in various cellular signaling and functions. Grb7 and its related family members Grb10 and Grb14 share a conserved domain architecture that includes an amino-terminal proline-rich region, a central segment termed the GM region (for Grb and Mig) which includes the RA, PIR, and pleckstrin homology (PH) domains, and a carboxyl-terminal SH2 domain. The tandem RA and PH domains of Grb7/10/14 are also found in a second adaptor family, Rap1-interacting adaptor molecule (RIAM) and lamellipodin, which is involved in actin-cytoskeleton rearrangement. Grb7/10/14 family proteins are phosphorylated on serine/threonine as well as tyrosine residues and are mainly localized to the cytoplasm. Grb7 could interact with activated N-Ras in transfected cells.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1033408890 119 GSHVVKVYSEDGTCRSLEVTAGTTARHVCEMLVQKTQALHDDCWSLVEVYQHLALERYLEDHESVVEVQATWPVGGDSRF 198
Cdd:cd16140     1 GPHVVKVYSEDGTCRSLEVTAGATARHVCEMLVQRAHCLDDESWSLVELHPHLALERCLEDHESVVEVQATWPAGGDSRF 80

                  ....*...
gi 1033408890 199 VFRKNYAK 206
Cdd:cd16140    81 VFRKNFAK 88

BPS (Between PH and SH2); The BPS (Between PH and SH2) domain, comprised of 2 beta strands and a C-terminal helix, is an approximately 45 residue region found in the adaptor proteins Grb7/10/14 that mediates inhibition of the tyrosine kinase domain of the insulin receptor by binding of the N-terminal portion of the BPS domain to the substrate peptide groove of the kinase, acting as a pseudosubstrate inhibitor.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*.
gi 1033408890 385 RSVSDNTLVAMDFSGCTGRVIENPNEALSVALEEAQAWRKKTIHRY 430
Cdd:pfam08947   1 RSVSESSLVAMDFSGAGGRVIENPEEALSEAEEEGAAWRKKTLRRC 46

Ras association (RalGDS/AF-6) domain; RasGTP effectors (in cases of AF6, canoe and RalGDS); putative RasGTP effectors in other cases. Recent evidence (not yet in MEDLINE) shows that some RA domains do NOT bind RasGTP. Predicted structure similar to that determined, and that of the RasGTP-binding domain of Raf kinase.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1033408890 119 GSHVVKVYSEDG----TCRSLEVTAGTTARHVCEMLVQKT-QALHDDCWSLVEVYQHLALERYLEDHESVVEVQATWPV- 192
Cdd:pfam00788   1 DDGVLKVYTEDGkpgtTYKTILVSSSTTAEEVIEALLEKFgLEDDPRDYVLVEVLERGGGERRLPDDECPLQIQLQWPRd 80

                          90
                  ....*....|...
gi 1033408890 193 GGDSRFVFRKNYA 205
Cdd:pfam00788  81 ASDSRFLLRKRDD 93

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 1033408890  250 PEIQGFLHLKE-VGRKVWKRFYFSLRRSGLYYSTKGTSKDPRHLQYCVDINESNVYYITQGKkqySTPTEFGFCIkphkt 328
Cdd:smart00233   1 VIKEGWLYKKSgGGKKSWKKRYFVLFNSTLLYYKSKKDKKSYKPKGSIDLSGCTVREAPDPD---SSKKPHCFEI----- 72

                           90       100
                   ....*....|....*....|....*.
gi 1033408890  329 RNGAKGLKLFCSEDEQSRTCWMAAFR 354
Cdd:smart00233  73 KTSDRKTLLLQAESEEEREKWVEALR 98

Src homology 2 (SH2) domain found in the growth factor receptor bound, subclass 7 (Grb7) proteins; The Grb family binds to the epidermal growth factor receptor (EGFR, erbB1) via their SH2 domains. Grb7 is part of the Grb7 family of proteins which also includes Grb10, and Grb14. They are composed of an N-terminal Proline-rich domain, a Ras Associating-like (RA) domain, a Pleckstrin Homology (PH) domain, a phosphotyrosine interaction region (PIR, BPS) and a C-terminal SH2 domain. The SH2 domains of Grb7, Grb10 and Grb14 preferentially bind to a different RTK. Grb7 binds strongly to the erbB2 receptor, unlike Grb10 and Grb14 which bind weakly to it. Grb7 family proteins are phosphorylated on serine/threonine as well as tyrosine residues. 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 1033408890 445 IHRTQPWFHGHISREDTQRLIIQQGLVDGVFLVRDSQRNPKGFVLSLCHLQKVKHYLILPIEEDGRPYYTMDDGQTRFTD 524
Cdd:cd10413     1 IHRTQPWFHGRISREESQRLIGQQGLVDGVFLVRESQRNPQGFVLSLCHLQKVKHYLILPSEEEGRLYFSMDDGQTRFTD 80

                          90       100
                  ....*....|....*....|....*...
gi 1033408890 525 LIQLVEFHQINRGILPCKLKHYCTSVAL 552
Cdd:cd10413    81 LLQLVEFHQLNRGILPCLLRHCCTRVAL 108

Amyloid beta (A4) Precursor protein-Binding, family B, member 1 Interacting Protein pleckstrin homology (PH) domain; APBB1IP consists of a Ras-associated (RA) domain, a PH domain, a family-specific BPS region, and a C-terminal SH2 domain. Grb7, Grb10 and Grb14 are paralogs that are also present in this hierarchy. These adapter proteins bind a variety of receptor tyrosine kinases, including the insulin and insulin-like growth factor-1 (IGF1) receptors. Grb10 and Grb14 are important tissue-specific negative regulators of insulin and IGF1 signaling based and may contribute to type 2 (non-insulin-dependent) diabetes in humans. RA-PH function as a single structural unit and is dimerized via a helical extension of the PH domain. The PH domain here are proposed to bind phosphoinositides non-cannonically ahd are unlikely to bind an activated GTPase. The tandem RA-PH domains are present in a second adapter-protein family, MRL proteins, Caenorhabditis elegans protein MIG-1012, the mammalian proteins RIAM and lamellipodin and the Drosophila melanogaster protein Pico12, all of which are Ena/VASP-binding proteins involved in actin-cytoskeleton rearrangement. 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.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1033408890 245 NSGSCPEIQGFLHLKEVGRKVWKRFYFSLRRSGLYYSTKGTSKDPRHLQYCVDINESNVYYITQGKKQYSTPTEFGFCIK 324
Cdd:cd01259     1 NSVSCPEIEGFLYLKEDGKKSWKKRYFVLRASGLYYSPKGKSKESRDLQCLAQFDDYNVYTGLNGKKKYKAPTDFGFCLK 80

                          90       100       110       120
                  ....*....|....*....|....*....|....*....|....
gi 1033408890 325 PHKTR-NGAKGLKLFCSEDEQSRTCWMAAFRLFKYGIQLYRNYQ 367
Cdd:cd01259    81 PNKQQeKGSKDIKYLCAEDEQSRTCWLTAIRLAKYGKQLYENYR 124

Ras-associating (RA) domain found in growth factor receptor-bound (Grb) protein 7; GRB7, also termed B47, or epidermal growth factor receptor GRB-7, or GRB7 adapter protein, is a signal-transducing cytoplasmic adaptor protein that is co-opted by numerous tyrosine kinases involved in various cellular signaling and functions. Grb7 and its related family members Grb10 and Grb14 share a conserved domain architecture that includes an amino-terminal proline-rich region, a central segment termed the GM region (for Grb and Mig) which includes the RA, PIR, and pleckstrin homology (PH) domains, and a carboxyl-terminal SH2 domain. The tandem RA and PH domains of Grb7/10/14 are also found in a second adaptor family, Rap1-interacting adaptor molecule (RIAM) and lamellipodin, which is involved in actin-cytoskeleton rearrangement. Grb7/10/14 family proteins are phosphorylated on serine/threonine as well as tyrosine residues and are mainly localized to the cytoplasm. Grb7 could interact with activated N-Ras in transfected cells.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1033408890 119 GSHVVKVYSEDGTCRSLEVTAGTTARHVCEMLVQKTQALHDDCWSLVEVYQHLALERYLEDHESVVEVQATWPVGGDSRF 198
Cdd:cd16140     1 GPHVVKVYSEDGTCRSLEVTAGATARHVCEMLVQRAHCLDDESWSLVELHPHLALERCLEDHESVVEVQATWPAGGDSRF 80

                  ....*...
gi 1033408890 199 VFRKNYAK 206
Cdd:cd16140    81 VFRKNFAK 88

Ras-associating (RA) domain found in growth factor receptor-bound (Grb) protein 7/10/14; The RA domain is highly conserved among the members of the Grb proteins family which includes Grb7, Grb10 and Grb14. Grb7/10/14 are multi-domain cytoplasmic adaptor proteins that are recruited to activated receptor tyrosine kinases. RA domain has the beta-grasp ubiquitin-like fold with low sequence similarity to ubiquitin (Ub). Ub is a protein modifier in eukaryotes that is involved in various cellular processes including transcriptional regulation, cell cycle control, and DNA repair in eukaryotes. Grb7 and its related family members Grb10 and Grb14 share a conserved domain architecture that includes an amino-terminal proline-rich region, a central segment termed the GM region (for Grb and Mig) which includes the RA, PIR, and pleckstrin homology (PH) domains, and a carboxyl-terminal SH2 domain. The tandem RA and PH domains of Grb7/10/14 are also found in a second adaptor family, Rap1-interacting adaptor molecule (RIAM) and lamellipodin, which is involved in actin-cytoskeleton rearrangement. Grb7/10/14 family proteins are phosphorylated on serine/threonine as well as tyrosine residues and are mainly localized to the cytoplasm.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1033408890 121 HVVKVYSEDGTCRSLEVTAGTTARHVCEMLVQKTQALHDDCWSLVEVYQHLALERYLEDHESVVEVQATWPVGGDSRFVF 200
Cdd:cd16124     2 QVVKVYSEDGTSRSVEVAADATARDVCQLLVQKAHALDDESWTLVEHHPHLGLERGLEDHELVVEVQSAWPVGGESKFVF 81

                  ....
gi 1033408890 201 RKNY 204
Cdd:cd16124    82 RKNY 85

Ras-associating (RA) domain found in growth factor receptor-bound (Grb) protein 14; Grb14, a member of cytoplasmic adaptor proteins, is a tissue-specific negative regulator of insulin signaling. RA domain has the beta-grasp ubiquitin-like fold with low sequence similarity to ubiquitin (Ub). Ubi is a protein modifier in eukaryotes that is involved in various cellular processes including transcriptional regulation, cell cycle control, and DNA repair in eukaryotes. A novel function of Grb14 RA domain is to interact with the nucleotide binding pocket of a cyclic nucleotide gated channel alpha subunit (CNGA1) and inhibits its activity. Grb7 and its related family members Grb10 and Grb14 share a conserved domain architecture that includes an amino-terminal proline-rich region, a central segment termed the GM region (for Grb and Mig) which includes the RA, PIR, and PH domains, and a carboxyl-terminal SH2 domain. Grb7/10/14 family proteins are phosphorylated on serine/threonine as well as tyrosine residues and are mainly localized to the cytoplasm.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1033408890 120 SHVVKVYSEDGTCRSLEVTAGTTARHVCEMLVQKTQALHDDCWSLVEVYQHLALERYLEDHESVVEVQATWPVGGDSRFV 199
Cdd:cd16139     1 KQVIKVYSEDDTSRALEVPNDITARDVCQLFILKNHYIDDHSWTLFEHLPHIGLERIIEDHESVIEVQSNWGMETDSRLY 80

                  ....*
gi 1033408890 200 FRKNY 204
Cdd:cd16139    81 FRKNY 85

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 1033408890  449 QPWFHGHISREDTQRLIIQQGlvDGVFLVRDSQRNPKGFVLSLCHLQKVKHYLILPIEEDGrpYYTmdDGQTRFTDLIQL 528
Cdd:smart00252   1 QPWYHGFISREEAEKLLKNEG--DGDFLVRDSESSPGDYVLSVRVKGKVKHYRIRRNEDGK--FYL--EGGRKFPSLVEL 74

                   ....*...
gi 1033408890  529 VEFHQINR 536
Cdd:smart00252  75 VEHYQKNS 82

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        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1033408890 450 PWFHGHISREDTQRLIIQQglVDGVFLVRDSQRNPKGFVLSLCH-LQKVKHYLilpIEEDGRPYYTMDDGQTRFTDLIQL 528
Cdd:cd00173     1 PWFHGSISREEAERLLRGK--PDGTFLVRESSSEPGDYVLSVRSgDGKVKHYL---IERNEGGYYLLGGSGRTFPSLPEL 75

                  ....
gi 1033408890 529 VEFH 532
Cdd:cd00173    76 VEHY 79

Src homology 2 (SH2) domain found in Carboxyl-Terminal Src Kinase (Csk); Both the C-terminal Src kinase (CSK) and CSK-homologous kinase (CHK) are members of the CSK-family of protein tyrosine kinases. These proteins suppress activity of Src-family kinases (SFK) by selectively phosphorylating the conserved C-terminal tail regulatory tyrosine by a similar mechanism. CHK is also capable of inhibiting SFKs by a non-catalytic mechanism that involves binding of CHK to SFKs to form stable protein complexes. The unphosphorylated form of SFKs is inhibited by CSK and CHK by a two-step mechanism. The first step involves the formation of a complex of SFKs with CSK/CHK with the SFKs in the complex are inactive. The second step, involves the phosphorylation of the C-terminal tail tyrosine of SFKs, which then dissociates and adopt an inactive conformation. The structural basis of how the phosphorylated SFKs dissociate from CSK/CHK to adopt the inactive conformation is not known. The inactive conformation of SFKs is stabilized by two intramolecular inhibitory interactions: (a) the pYT:SH2 interaction in which the phosphorylated C-terminal tail tyrosine (YT) binds to the SH2 domain, and (b) the linker:SH3 interaction of which the SH2-kinase domain linker binds to the SH3 domain. SFKs are activated by multiple mechanisms including binding of the ligands to the SH2 and SH3 domains to displace the two inhibitory intramolecular interactions, autophosphorylation, and dephosphorylation of YT. By selective phosphorylation and the non-catalytic inhibitory mechanism CSK and CHK are able to inhibit the active forms of SFKs. CSK and CHK are regulated by phosphorylation and inter-domain interactions. They both contain SH3, SH2, and kinase domains separated by the SH3-SH2 connector and SH2 kinase linker, intervening segments separating the three domains. They lack a conserved tyrosine phosphorylation site in the kinase domain and the C-terminal tail regulatory tyrosine phosphorylation site. The CSK SH2 domain is crucial for stabilizing the kinase domain in the active conformation. A disulfide bond here regulates CSK kinase activity. The subcellular localization and activity of CSK are regulated by its SH2 domain. 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 1033408890 448 TQPWFHGHISREDTQRLIIQQGlvDGVFLVRDSQRNPKGFVLSLCHLQKVKHYLIlpIEEDGRpyYTMDDGQTrFTDLIQ 527
Cdd:cd09937     2 LMPWFHGKISREEAERLLQPPE--DGLFLVRESTNYPGDYTLCVSFEGKVEHYRV--IYRNGK--LTIDEEEY-FENLIQ 74

                          90
                  ....*....|....*..
gi 1033408890 528 LVEFHQINRGILPCKLK 544
Cdd:cd09937    75 LVEHYTKDADGLCTRLV 91

N-terminal Src homology 2 (SH2) domain found in Zeta-chain-associated protein kinase 70 (ZAP-70) and Spleen tyrosine kinase (Syk) proteins; ZAP-70 and Syk comprise a family of hematopoietic cell specific protein tyrosine kinases (PTKs) that are required for antigen and antibody receptor function. ZAP-70 is expressed in T and natural killer (NK) cells and Syk is expressed in B cells, mast cells, polymorphonuclear leukocytes, platelets, macrophages, and immature T cells. They are required for the proper development of T and B cells, immune receptors, and activating NK cells. They consist of two N-terminal Src homology 2 (SH2) domains and a C-terminal kinase domain separated from the SH2 domains by a linker or hinge region. Phosphorylation of both tyrosine residues within the Immunoreceptor Tyrosine-based Activation Motifs (ITAM; consensus sequence Yxx[LI]x(7,8)Yxx[LI]) by the Src-family PTKs is required for efficient interaction of ZAP-70 and Syk with the receptor subunits and for receptor function. ZAP-70 forms two phosphotyrosine binding pockets, one of which is shared by both SH2 domains. In Syk the two SH2 domains do not form such a phosphotyrosine-binding site. The SH2 domains here are believed to function independently. In addition, the two SH2 domains of Syk display flexibility in their relative orientation, allowing Syk to accommodate a greater variety of spacing sequences between the ITAM phosphotyrosines and singly phosphorylated non-classical ITAM ligands. This model contains the N-terminus SH2 domains of both Syk and Zap70. 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 1033408890 450 PWFHGHISREDTQRLIIQQGLVDGVFLVRDSQRNPKGFVLSLCHLQKVKHYlilPIEEDGRPYYTMDDGQTrFTDLIQLV 529
Cdd:cd09938     2 PFFYGSITREEAEEYLKLAGMSDGLFLLRQSLRSLGGYVLSVCHGRKFHHY---TIERQLNGTYAIAGGKA-HCGPAELC 77

                          90
                  ....*....|....*...
gi 1033408890 530 EFHQINRGILPCKLKHYC 547
Cdd:cd09938    78 EYHSTDLDGLVCLLRKPC 95

Ras-associating (RA) domain of Mig10/RIAM/Lpd (MRL) family; MRL proteins share a common structural architecture, including a central structural unit consisting of a Ras-associating (RA) domain and a pleckstrin homology (PH) domain, an upstream coiled-coil region, and a number of polyproline motifs. RA domain-containing proteins function by interacting with Ras proteins directly or indirectly and are involved in several different functions ranging from tumor suppression to being oncoproteins. Ras proteins are small GTPases that are involved in cellular signal transduction. RA domain has the beta-grasp ubiquitin-like fold with low sequence similarity to ubiquitin (Ub). Ub is a protein modifier in eukaryotes that is involved in various cellular processes including transcriptional regulation, cell cycle control, and DNA repair in eukaryotes. RA and PH form a tandem domain pair (RA-PH), and serve tightly coordinated functions in both Ras GTPase signaling via the RA domain and membrane translocalization via the PH domain. MRL proteins have distinct functions in cell migration and adhesion, signaling, and in cell growth.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1033408890 122 VVKVYSEDGTCRSLEVTAGTTARHVCEMLVQKTqalHDDC---WSLVEVYQHLALERYLEDHESVVEVQATW 190
Cdd:cd01787     3 VVKVHMEDGSSKTLLVDERMTVRQVLKQLIEKN---HCDPsvdWCLVEQYPDLYMERVFEDHEKLVENLLNW 71

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        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1033408890 451 WFHGHISREDTQRLIIQQGlVDGVFLVRDSQRNPKGFVLS-LCHLQKVKHYLILpiEEDGRpyYTMDDGQTrFTDLIQLV 529
Cdd:cd09931     2 WFHGHLSGKEAEKLLLEKG-KPGSFLVRESQSKPGDFVLSvRTDDDKVTHIMIR--CQGGK--YDVGGGEE-FDSLTDLV 75

                  ....*.
gi 1033408890 530 EFHQIN 535
Cdd:cd09931    76 EHYKKN 81

Ras-associating (RA) domain found in Rap1-GTP-interacting adapter molecule (RIAM); RIAM, also termed amyloid beta A4 precursor protein-binding family B member 1-interacting protein, or APBB1-interacting protein 1, or proline-rich EVH1 ligand 1 (PREL-1), or proline-rich protein 73, or retinoic acid-responsive proline-rich protein 1 (RARP-1), is a member of MRL (Mig10/RIAM/Lpd) family proteins that regulates cell migration and promote lamellipodia protrusion in fibroblast by interacting with Ena/VASP proteins. RIAM regulates cell migration and mediates Rap1-induced cell adhesion. MRL proteins share a common structural architecture, including a central structural unit consisting of an RA domain and a pleckstrin homology (PH) domain, an upstream coiled-coil region, and a number of polyproline motifs. RA domain-containing proteins function by interacting with Ras proteins directly or indirectly and are involved in several different functions ranging from tumor suppression to being oncoproteins. RA domain has the beta-grasp ubiquitin-like fold with low sequence similarity to ubiquitin (Ub). Ub is a protein modifier in eukaryotes that is involved in various cellular processes including transcriptional regulation, cell cycle control, and DNA repair in eukaryotes. RIAM also contains a helical region at the amino terminus for talin binding. RA and PH form a tandem domain pair (RA-PH), and serve tightly coordinated functions in both Ras GTPase signaling via the RA domain and membrane translocalization via the PH domain.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1033408890 122 VVKVYSEDGTCRSLEVTAGTTARHVCEMLVQKTqalHDDC---WSLVEVYQHLALERYLEDHESVVEVQATWPVGGDSRF 198
Cdd:cd16137     4 VVKVHMNDSSTKTLMVDERQTVRDVLDNLFEKT---HCDCnvdWCLYEVNPELQIERFFEDHENVVEVLSDWTRDSENKV 80

                  ....*....
gi 1033408890 199 VFRKNYAKY 207
Cdd:cd16137    81 LFLEKKEKY 89

Src homology 2 (SH2) domain found in Abelson murine lymphosarcoma virus (ABL) proteins; ABL-family proteins are highly conserved tyrosine kinases. Each ABL protein contains an SH3-SH2-TK (Src homology 3-Src homology 2-tyrosine kinase) domain cassette, which confers autoregulated kinase activity and is common among nonreceptor tyrosine kinases. Several types of posttranslational modifications control ABL catalytic activity, subcellular localization, and stability, with consequences for both cytoplasmic and nuclear ABL functions. Binding partners provide additional regulation of ABL catalytic activity, substrate specificity, and downstream signaling. By combining this cassette with actin-binding and -bundling domain, ABL proteins are capable of connecting phosphoregulation with actin-filament reorganization. Vertebrate paralogs, ABL1 and ABL2, have evolved to perform specialized functions. ABL1 includes nuclear localization signals and a DNA binding domain which is used to mediate DNA damage-repair functions, while ABL2 has additional binding capacity for actin and for microtubules to enhance its cytoskeletal remodeling functions. SH2 is involved in several autoinhibitory mechanism that constrain the enzymatic activity of the ABL-family kinases. In one mechanism SH2 and SH3 cradle the kinase domain while a cap sequence stabilizes the inactive conformation resulting in a locked inactive state. Another involves phosphatidylinositol 4,5-bisphosphate (PIP2) which binds the SH2 domain through residues normally required for phosphotyrosine binding in the linker segment between the SH2 and kinase domains. The SH2 domain contributes to ABL catalytic activity and target site specificity. It is thought that the ABL catalytic site and SH2 pocket have coevolved to recognize the same sequences. Recent work now supports a hierarchical processivity model in which the substrate target site most compatible with ABL kinase domain preferences is phosphorylated with greatest efficiency. If this site is compatible with the ABL SH2 domain specificity, it will then reposition and dock in the SH2 pocket. This mechanism also explains how ABL kinases phosphorylates poor targets on the same substrate if they are properly positioned and how relatively poor substrate proteins might be recruited to ABL through a complex with strong substrates that can also dock with the SH2 pocket. 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 1033408890 450 PWFHGHISREDTQRLIiqQGLVDGVFLVRDSQRNPKGFVLSLCHLQKVKHYLIlPIEEDGRPYYTMDdgqTRFTDLIQLV 529
Cdd:cd09935     4 SWYHGPISRNAAEYLL--SSGINGSFLVRESESSPGQYSISLRYDGRVYHYRI-SEDSDGKVYVTQE---HRFNTLAELV 77

                          90
                  ....*....|....*.
gi 1033408890 530 EFHQINRGILPCKLKH 545
Cdd:cd09935    78 HHHSKNADGLITTLRY 93

Src homology 2 domain found in Growth factor receptor-bound protein 2 (Grb2) and similar proteins; The adaptor proteins here include homologs Grb2 in humans, Sex muscle abnormal protein 5 (Sem-5) in Caenorhabditis elegans, and Downstream of receptor kinase (drk) in Drosophila melanogaster. They are composed of one SH2 and two SH3 domains. Grb2/Sem-5/drk regulates the Ras pathway by linking the tyrosine kinases to the Ras guanine nucleotide releasing protein Sos, which converts Ras to the active GTP-bound state. The SH2 domain of Grb2/Sem-5/drk binds class II phosphotyrosyl peptides while its SH3 domain binds to Sos and Sos-derived, proline-rich peptides. Besides it function in Ras signaling, Grb2 is also thought to play a role in apoptosis. Unlike most SH2 structures in which the peptide binds in an extended conformation (such that the +3 peptide residue occupies a hydrophobic pocket in the protein, conferring a modest degree of selectivity), Grb2 forms several hydrogen bonds via main chain atoms with the side chain of +2 Asn. 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 1033408890 450 PWFHGHISREDTQRlIIQQGLVDGVFLVRDSQRNPKGFVLSLCHLQKVKHYLILPiEEDGRpYYTMddgQTRFTDLIQLV 529
Cdd:cd09941     4 PWFHGKISRAEAEE-ILMNQRPDGAFLIRESESSPGDFSLSVKFGNDVQHFKVLR-DGAGK-YFLW---VVKFNSLNELV 77

                  ....
gi 1033408890 530 EFHQ 533
Cdd:cd09941    78 DYHR 81

C-terminal Src homology 2 (SH2) domain found in SH2 domains, ANK, and kinase domain (shark) proteins; These non-receptor protein-tyrosine kinases contain two SH2 domains, five ankyrin (ANK)-like repeats, and a potential tyrosine phosphorylation site in its carboxyl-terminal tail which resembles the phosphorylation site in members of the src family. Like, mammalian non-receptor protein-tyrosine kinases, ZAP-70 and syk proteins, they do not have SH3 domains. However, the presence of ANK makes these unique among protein-tyrosine kinases. Both tyrosine kinases and ANK repeats have been shown to transduce developmental signals, and SH2 domains are known to participate intimately in tyrosine kinase signaling. These tyrosine kinases are believed to be involved in epithelial cell polarity. The members of this family include the shark (SH2 domains, ANK, and kinase domain) gene in Drosophila and yellow fever mosquitos, as well as the hydra protein HTK16. Drosophila Shark is proposed to transduce intracellularly the Crumbs, a protein necessary for proper organization of ectodermal epithelia, intercellular signal. 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 1033408890 451 WFHGHISREDTQRLIIQQGLVDGVFLVRDSQRNPKGFVLSLCHLQKVKHYLIlpIEEDGRpYYTMDDGQTrFTDLIQLVE 530
Cdd:cd10348     2 WLHGALDRNEAVEILKQKADADGSFLVRYSRRRPGGYVLTLVYENHVYHFEI--QNRDDK-WFYIDDGPY-FESLEHLIE 77

Src homology 2 (SH2) domain found in feline sarcoma, Fujinami poultry sarcoma, and fes-related (Fes/Fps/Fer) proteins; The Fps family consists of members Fps/Fes and Fer/Flk/Tyk3. They are cytoplasmic protein-tyrosine kinases implicated in signaling downstream from cytokines, growth factors and immune receptors. Fes/Fps/Fer contains three coiled-coil regions, an SH2 (Src-homology-2) and a TK (tyrosine kinase catalytic) domain signature. Members here include: Fps/Fes, Fer, Kin-31, and 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 1033408890 446 HRTQPWFHGHISREDTQRLIIQQGlvDgvFLVRDSQRNPKG---FVLSLCHLQKVKHYLILpiEEDGRPYYTMDdgqTRF 522
Cdd:cd10361     3 LENEPYYHGLLPREDAEELLKNDG--D--FLVRKTEPKGGGkrkLVLSVRWDGKIRHFVIN--RDDGGKYYIEG---KSF 73

                          90
                  ....*....|....
gi 1033408890 523 TDLIQLVEFHQINR 536
Cdd:cd10361    74 KSISELINYYQKTK 87

C-terminal Src homology 2 (SH2) domain found in Spleen tyrosine kinase (Syk) proteins; ZAP-70 and Syk comprise a family of hematopoietic cell specific protein tyrosine kinases (PTKs) that are required for antigen and antibody receptor function. ZAP-70 is expressed in T and natural killer (NK) cells and Syk is expressed in B cells, mast cells, polymorphonuclear leukocytes, platelets, macrophages, and immature T cells. They are required for the proper development of T and B cells, immune receptors, and activating NK cells. They consist of two N-terminal Src homology 2 (SH2) domains and a C-terminal kinase domain separated from the SH2 domains by a linker or hinge region. Phosphorylation of both tyrosine residues within the Immunoreceptor Tyrosine-based Activation Motifs (ITAM; consensus sequence Yxx[LI]x(7,8)Yxx[LI]) by the Src-family PTKs is required for efficient interaction of ZAP-70 and Syk with the receptor subunits and for receptor function. ZAP-70 forms two phosphotyrosine binding pockets, one of which is shared by both SH2 domains. In Syk the two SH2 domains do not form such a phosphotyrosine-binding site. The SH2 domains here are believed to function independently. In addition, the two SH2 domains of Syk display flexibility in their relative orientation, allowing Syk to accommodate a greater variety of spacing sequences between the ITAM phosphotyrosines and singly phosphorylated non-classical ITAM ligands. This model contains the C-terminus SH2 domains of Syk. 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 1033408890 450 PWFHGHISREDTQRLIIQQGLVDGVFLVRdSQRNPKGFVLSLCHLQKVKHYlilPIEEDGRPYYTMDDGQtRFTDLIQLV 529
Cdd:cd10401     4 PWFHGKISREESEQILLIGSKTNGKFLIR-ERDNNGSYALCLLHDGKVLHY---RIDKDKTGKLSIPDGK-KFDTLWQLV 78

                  .
gi 1033408890 530 E 530
Cdd:cd10401    79 E 79

Ras-associating (RA) domain found in Caenorhabditis elegans abnormal cell migration protein 10 (MIG-10) and similar proteins; MIG-10 is lamellipodin (Lpd) found in C. elegans. It stabilizes invading cell adhesion to basement membrane and is a negative transcriptional target of Evi-1 proto-oncogene, EGL-43, in C. elegans. It also shows netrin-independent functions and is a transcriptional target of FOS-1A, a transcription factor that promotes basement membrane breaching, during anchor cell invasion in C. elegans. MIG-10 is a member of MRL (Mig10/RIAM/Lpd) family of proteins that is involved in antero-posterior migration of embryonic neurons CAN (canalassociated neurons), ALM (anterior lateral microtubule cells) and HSN (hermaphrodite-specific neurons). MRL proteins share a common structural architecture, including a central structural unit consisting of an RA domain and a pleckstrin homology (PH) domain, an upstream coiled-coil region, and a number of polyproline motifs. RA domain-containing proteins function by interacting with Ras proteins directly or indirectly and are involved in several different functions ranging from tumor suppression to being oncoproteins. RA domain has the beta-grasp ubiquitin-like fold with low sequence similarity to ubiquitin (Ub). Ub is a protein modifier in eukaryotes that is involved in various cellular processes including transcriptional regulation, cell cycle control, and DNA repair in eukaryotes. RA and PH form a tandem domain pair (RA-PH), and serve tightly coordinated functions in both Ras GTPase signaling via the RA domain and membrane translocalization via the PH domain.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1033408890 123 VKVYSEDGTCRSLEVTAGTTARHVCEMLVQKTQALHDDCWSLVEVYQHLALERYLEDHESVVEVQATWPVGGDSRFVF 200
Cdd:cd16138     5 VKAFTEDGSAKSLLVDERMTVGHVTRLLADKNHVAMMPDWAIVEHIPDLYMERVYEDHEKLVENLMMWTRDSPNRLLF 82

Src homology 2 (SH2) domain found in SH2-containing inositol-5'-phosphatase (SHIP) and SLAM-associated protein (SAP); The SH2-containing inositol-5'-phosphatase, SHIP (also called SHIP1/SHIP1a), is a hematopoietic-restricted phosphatidylinositide phosphatase that translocates to the plasma membrane after extracellular stimulation and hydrolyzes the phosphatidylinositol-3-kinase (PI3K)-generated second messenger PI-3,4,5-P3 (PIP3) to PI-3,4-P2. As a result, SHIP dampens down PIP3 mediated signaling and represses the proliferation, differentiation, survival, activation, and migration of hematopoietic cells. PIP3 recruits lipid-binding pleckstrin homology(PH) domain-containing proteins to the inner wall of the plasma membrane and activates them. PH domain-containing downstream effectors include the survival/proliferation enhancing serine/threonine kinase, Akt (protein kinase B), the tyrosine kinase, Btk, the regulator of protein translation, S6K, and the Rac and cdc42 guanine nucleotide exchange factor, Vav. SHIP is believed to act as a tumor suppressor during leukemogenesis and lymphomagenesis, and may play a role in activating the immune system to combat cancer. SHIP contains an N-terminal SH2 domain, a centrally located phosphatase domain that specifically hydrolyzes the 5'-phosphate from PIP3, PI-4,5-P2 and inositol-1,3,4,5- tetrakisphosphate (IP4), a C2 domain, that is an allosteric activating site when bound by SHIP's enzymatic product, PI-3,4-P2; 2 NPXY motifs that bind proteins with a phosphotyrosine binding (Shc, Dok 1, Dok 2) or an SH2 (p85a, SHIP2) domain; and a proline-rich domain consisting of four PxxP motifs that bind a subset of SH3-containing proteins including Grb2, Src, Lyn, Hck, Abl, PLCg1, and PIAS1. The SH2 domain of SHIP binds to the tyrosine phosphorylated forms of Shc, SHP-2, Doks, Gabs, CD150, platelet-endothelial cell adhesion molecule, Cas, c-Cbl, immunoreceptor tyrosine-based inhibitory motifs (ITIMs), and immunoreceptor tyrosine-based activation motifs (ITAMs). The X-linked lymphoproliferative syndrome (XLP) gene encodes SAP (also called SH2D1A/DSHP) a protein that consists of a 5 residue N-terminus, a single SH2 domain, and a short 25 residue C-terminal tail. XLP is characterized by an extreme sensitivity to Epstein-Barr virus. Both T and natural killer (NK) cell dysfunctions have been seen in XLP patients. SAP binds the cytoplasmic tail of Signaling lymphocytic activation molecule (SLAM), 2B4, Ly-9, and CD84. SAP is believed to function as a signaling inhibitor, by blocking or regulating binding of other signaling proteins. SAP and the SAP-like protein EAT-2 recognize the sequence motif TIpYXX(V/I), which is found in the cytoplasmic domains of a restricted number of T, B, and NK cell surface receptors and are proposed to be natural inhibitors or regulators of the physiological role of a small family of receptors on the surface of these cells. 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 1033408890 449 QPWFHGHISREDTQRLIIQQGlVDGVFLVRDSQRNPKGFVLSLCHLQKVKHYLILPIEEDGRPYYTMDDGQTR-FTDLIQ 527
Cdd:cd10343     3 PPWYHGNITRSKAEELLSKAG-KDGSFLVRDSESVSGAYALCVLYQNCVHTYRILPNAEDKLSVQASEGVPVRfFTTLPE 81

                  ....*.
gi 1033408890 528 LVEFHQ 533
Cdd:cd10343    82 LIEFYQ 87

N-terminal Src homology 2 (N-SH2) domain in Phospholipase C gamma; Phospholipase C gamma is a signaling molecule that is recruited to the C-terminal tail of the receptor upon autophosphorylation of a highly conserved tyrosine. PLCgamma is composed of a Pleckstrin homology (PH) domain followed by an elongation factor (EF) domain, 2 catalytic regions of PLC domains that flank 2 tandem SH2 domains (N-SH2, C-SH2), and ending with a SH3 domain and C2 domain. N-SH2 SH2 domain-mediated interactions represent a crucial step in transmembrane signaling by receptor tyrosine kinases. SH2 domains recognize phosphotyrosine (pY) in the context of particular sequence motifs in receptor phosphorylation sites. Both N-SH2 and C-SH2 have a very similar binding affinity to pY. But in growth factor stimulated cells these domains bind to different target proteins. N-SH2 binds to pY containing sites in the C-terminal tails of tyrosine kinases and other receptors. Recently it has been shown that this interaction is mediated by phosphorylation-independent interactions between a secondary binding site found exclusively on the N-SH2 domain and a region of the FGFR1 tyrosine kinase domain. This secondary site on the SH2 cooperates with the canonical pY site to regulate selectivity in mediating a specific cellular process. C-SH2 binds to an intramolecular site on PLCgamma itself which allows it to hydrolyze phosphatidylinositol-4,5-bisphosphate into diacylglycerol and inositol triphosphate. These then activate protein kinase C and release calcium. 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 1033408890 446 HRTQPWFHGHIS--REDTQRLIIQ-QGLVDGVFLVRDSQRNPKGFVLSLCHLQKVKHYLILPIEEDGRP-YYTMDDGQtr 521
Cdd:cd10341     1 HFTEPWFHGKLGdgRDEAEKLLLEyCEGGDGTFLVRESETFVGDYTLSFWRNGKVQHCRIRSRQENGEKkYYLTDNLV-- 78

                          90
                  ....*....|....*
gi 1033408890 522 FTDLIQLVEFHQINR 536
Cdd:cd10341    79 FDSLYELIDYYRQNP 93

Ras-associating (RA) domain found in Arf-GAP with Rho-GAP domain, ANK repeat and PH domain-containing proteins ARAP1, ARAP2, ARAP3, and similar proteins; ARAPs are phosphatidylinositol 3,4,5-trisphosphate (PtdIns(3,4,5)P(3))-dependent Arf Rap-activated guanosine triphosphatase (GTPase)-activating proteins (GAPs). They contain multiple functional domains, including ArfGAP and RhoGAP domains, as well as a sterile alpha motif (Sam) domain, five PH domains, and a RA domain. The RA domain has the beta-grasp ubiquitin-like fold with low sequence similarity to ubiquitin (Ub); Ub is a protein modifier in eukaryotes that is involved in various cellular processes including transcriptional regulation, cell cycle control, and DNA repair in eukaryotes.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1033408890 123 VKVYSEDGTCRSLEVTAGTTARHVCEMLVQKTQ-ALHDDCWSLVEVYQHLALERYLEDHESVVEVQATWPV--GGDSRFV 199
Cdd:cd17113     8 VYIEEKEGTSVNIKVTPTMTAEEVVEQALNKKNlGGPEGNWALFEVIEDGGLERPLHESEKVLDVVLRWSQwpRKSNYLC 87

                  ....*
gi 1033408890 200 FRKNY 204
Cdd:cd17113    88 VKKNP 92

Src homology 2 domain found in the SH2 domain containing protein 4A (SH2D4A); SH2D4A contains a single SH2 domain. 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 1033408890 450 PWFHGHISREDTQRLIiqQGLVDGVFLVRDSQRnPKGFVLSLCHLQKVKHYLilpIEEDGRPYYTMDDGQTRFTDLIQLV 529
Cdd:cd10350     8 PWFHGILTLKKANELL--LSTMPGSFLIRVSEK-IKGYALSYLSEEGCKHFL---IDASADSYSFLGVDQLQHATLADLV 81

                  ....
gi 1033408890 530 EFHQ 533
Cdd:cd10350    82 EYHK 85

Ras-associating (RA) domain found in the adapter protein lamellipodin (Lpd); Lpd, also termed Ras-associated and pleckstrin homology domains-containing protein 1 (RAPH1), or amyotrophic lateral sclerosis 2 chromosomal region candidate gene 18 protein, or amyotrophic lateral sclerosis 2 chromosomal region candidate gene 9 protein, or proline-rich EVH1 ligand 2 (PREL-2), or protein RMO1, is a member of MRL (Mig10/RIAM/Lpd) family proteins that regulates cell migration and promote lamellipodia protrusion in fibroblast by interacting with Ena/VASP proteins. MRL proteins share a common structural architecture, including a central structural unit consisting of an RA domain and a pleckstrin homology (PH) domain, an upstream coiled-coil region, and a number of polyproline motifs. Lpd also contains a helical region at the amino terminus for talin binding. RA domain-containing proteins function by interacting with Ras proteins directly or indirectly and are involved in several different functions ranging from tumor suppression to being oncoproteins. RA domain has the beta-grasp ubiquitin-like fold with low sequence similarity to ubiquitin (Ub). Ub is a protein modifier in eukaryotes that is involved in various cellular processes including transcriptional regulation, cell cycle control, and DNA repair in eukaryotes. RA and PH domain in Lpd form a tandem domain pair (RA-PH), and serve tightly coordinated functions in both Ras GTPase signaling via the RA domain and membrane translocalization via the PH domain. Lpd also exhibits other unique enzymatic functions including its catalytic activity of butyrylcholinesterase, a potent therapeutic treatment targeting cocaine abuse.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1033408890 122 VVKVYSEDGTCRSLEVTAGTTARHVCEMLVQKTQALHDDCWSLVEVYQHLALERYLEDHESVVEVQATWPVGGDSRFVFR 201
Cdd:cd16136     6 VIRVHMSDDSSKTMMVDERQTVRQVLDNLMDKSHCGYSLDWSLVETISELQMERIFEDHENLVENLLNWTRDSQNKLMFV 85

                  ....*
gi 1033408890 202 KNYAK 206
Cdd:cd16136    86 ERIEK 90

N-terminal Src homology 2 (N-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): [IVL]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        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1033408890 451 WFHGHISREDTQRLIIQQGlVDGVFLVRDSQRNPKGFVLSLCHLQKVKHYLILPIEEDGRPYytmddGQTRFTDLIQLVE 530
Cdd:cd10340     2 WFHPVISGIEAENLLKTRG-VDGSFLARPSKSNPGDFTLSVRRGDEVTHIKIQNTGDYYDLY-----GGEKFATLSELVQ 75

                  ....*....
gi 1033408890 531 FHQINRGIL 539
Cdd:cd10340    76 YYMEQHGQL 84

Src homology 2 (SH2) domain found in Tec-like proteins; The Tec protein tyrosine kinase is the founding member of a family that includes Btk, Itk, Bmx, and Txk. The members have a PH domain, a zinc-binding motif, a SH3 domain, a SH2 domain, and a protein kinase catalytic domain. Btk is involved in B-cell receptor signaling with mutations in Btk responsible for X-linked agammaglobulinemia (XLA) in humans and X-linked immunodeficiency (xid) in mice. Itk is involved in T-cell receptor signaling. Tec is expressed in both T and B cells, and is thought to function in activated and effector T lymphocytes to induce the expression of genes regulated by NFAT transcription factors. 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 1033408890 451 WFHGHISREDTQRLIIQQGlVDGVFLVRDSqRNPKGFVLSL----CHLQKVKHYLILPIEEDgrPYYTMDdgQTRFTDLI 526
Cdd:cd09934     8 WYVGDMSRQRAESLLKQED-KEGCFVVRNS-STKGLYTVSLftkvPGSPHVKHYHIKQNARS--EFYLAE--KHCFETIP 81