Src homology 2 domain found in dual adaptor for phosphotyrosine and 3-phosphoinositides ( DAPP1)/B lymphocyte adaptor molecule of 32 kDa (Bam32)-like proteins; DAPP1/Bam32 contains a putative myristoylation site at its N-terminus, followed by a SH2 domain, and a pleckstrin homology (PH) domain at its C-terminus. DAPP1 could potentially be recruited to the cell membrane by any of these domains. Its putative myristoylation site could facilitate the interaction of DAPP1 with the lipid bilayer. Its SH2 domain may also interact with phosphotyrosine residues on membrane-associated proteins such as activated tyrosine kinase receptors. And finally its PH domain exhibits a high-affinity interaction with the PtdIns(3,4,5)P(3) PtdIns(3,4)P(2) second messengers produced at the cell membrane following the activation of PI 3-kinases. DAPP1 is thought to interact with both tyrosine phosphorylated proteins and 3-phosphoinositides and therefore may play a role in regulating the location and/or activity of such proteins(s) in response to agonists that elevate PtdIns(3,4,5)P(3) and PtdIns(3,4)P(2). This protein is likely to play an important role in triggering signal transduction pathways that lie downstream from receptor tyrosine kinases and PI 3-kinase. It is likely that DAPP1 functions as an adaptor to recruit other proteins to the plasma membrane in response to extracellular signals. 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 157819323  28 DLFQDLGWYHSNLTRHAAEALLLSNGRDGSYLLRDSNEQTGLYSLSVRAKDSVKHFHVEYTGYSFKFGFNEYSSLKDFVK 107
Cdd:cd10355    1 ELLQSLGWYHGNLTRHAAEALLLSNGVDGSYLLRNSNEGTGLFSLSVRAKDSVKHFHVEYTGYSFKFGFNEFSSLQDFVK 80

                         90
                 ....*....|..
gi 157819323 108 HFANQPLIGSET 119
Cdd:cd10355   81 HFANQPLIGSET 92

Src homology 2 domain found in dual adaptor for phosphotyrosine and 3-phosphoinositides ( DAPP1)/B lymphocyte adaptor molecule of 32 kDa (Bam32)-like proteins; DAPP1/Bam32 contains a putative myristoylation site at its N-terminus, followed by a SH2 domain, and a pleckstrin homology (PH) domain at its C-terminus. DAPP1 could potentially be recruited to the cell membrane by any of these domains. Its putative myristoylation site could facilitate the interaction of DAPP1 with the lipid bilayer. Its SH2 domain may also interact with phosphotyrosine residues on membrane-associated proteins such as activated tyrosine kinase receptors. And finally its PH domain exhibits a high-affinity interaction with the PtdIns(3,4,5)P(3) PtdIns(3,4)P(2) second messengers produced at the cell membrane following the activation of PI 3-kinases. DAPP1 is thought to interact with both tyrosine phosphorylated proteins and 3-phosphoinositides and therefore may play a role in regulating the location and/or activity of such proteins(s) in response to agonists that elevate PtdIns(3,4,5)P(3) and PtdIns(3,4)P(2). This protein is likely to play an important role in triggering signal transduction pathways that lie downstream from receptor tyrosine kinases and PI 3-kinase. It is likely that DAPP1 functions as an adaptor to recruit other proteins to the plasma membrane in response to extracellular signals. 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 157819323  28 DLFQDLGWYHSNLTRHAAEALLLSNGRDGSYLLRDSNEQTGLYSLSVRAKDSVKHFHVEYTGYSFKFGFNEYSSLKDFVK 107
Cdd:cd10355    1 ELLQSLGWYHGNLTRHAAEALLLSNGVDGSYLLRNSNEGTGLFSLSVRAKDSVKHFHVEYTGYSFKFGFNEFSSLQDFVK 80

                         90
                 ....*....|..
gi 157819323 108 HFANQPLIGSET 119
Cdd:cd10355   81 HFANQPLIGSET 92

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 157819323    35 WYHSNLTRHAAEALLLSNGrDGSYLLRDSNEQTGLYSLSVRAKDSVKHFHVEYTGYSfKFGFNE---YSSLKDFVKHFAN 111
Cdd:smart00252   3 WYHGFISREEAEKLLKNEG-DGDFLVRDSESSPGDYVLSVRVKGKVKHYRIRRNEDG-KFYLEGgrkFPSLVELVEHYQK 80

                   ...
gi 157819323   112 QPL 114
Cdd:smart00252  81 NSL 83

PH domain; PH stands for pleckstrin homology.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 157819323  166 TKEGYLTKQG-GLVKTWKTRWFTLQRNELKYFKDQMSP---EPIRILDLTECSAVQF--DYSQDRVNCFCLVF----PFR 235
Cdd:pfam00169   2 VKEGWLLKKGgGKKKSWKKRYFVLFDGSLLYYKDDKSGkskEPKGSISLSGCEVVEVvaSDSPKRKFCFELRTgertGKR 81

                          90       100
                  ....*....|....*....|
gi 157819323  236 TFYLCAKTGVEADEWIKILR 255
Cdd:pfam00169  82 TYLLQAESEEERKDWIKAIQ 101

Src homology 2 domain found in dual adaptor for phosphotyrosine and 3-phosphoinositides ( DAPP1)/B lymphocyte adaptor molecule of 32 kDa (Bam32)-like proteins; DAPP1/Bam32 contains a putative myristoylation site at its N-terminus, followed by a SH2 domain, and a pleckstrin homology (PH) domain at its C-terminus. DAPP1 could potentially be recruited to the cell membrane by any of these domains. Its putative myristoylation site could facilitate the interaction of DAPP1 with the lipid bilayer. Its SH2 domain may also interact with phosphotyrosine residues on membrane-associated proteins such as activated tyrosine kinase receptors. And finally its PH domain exhibits a high-affinity interaction with the PtdIns(3,4,5)P(3) PtdIns(3,4)P(2) second messengers produced at the cell membrane following the activation of PI 3-kinases. DAPP1 is thought to interact with both tyrosine phosphorylated proteins and 3-phosphoinositides and therefore may play a role in regulating the location and/or activity of such proteins(s) in response to agonists that elevate PtdIns(3,4,5)P(3) and PtdIns(3,4)P(2). This protein is likely to play an important role in triggering signal transduction pathways that lie downstream from receptor tyrosine kinases and PI 3-kinase. It is likely that DAPP1 functions as an adaptor to recruit other proteins to the plasma membrane in response to extracellular signals. 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 157819323  28 DLFQDLGWYHSNLTRHAAEALLLSNGRDGSYLLRDSNEQTGLYSLSVRAKDSVKHFHVEYTGYSFKFGFNEYSSLKDFVK 107
Cdd:cd10355    1 ELLQSLGWYHGNLTRHAAEALLLSNGVDGSYLLRNSNEGTGLFSLSVRAKDSVKHFHVEYTGYSFKFGFNEFSSLQDFVK 80

                         90
                 ....*....|..
gi 157819323 108 HFANQPLIGSET 119
Cdd:cd10355   81 HFANQPLIGSET 92

Src homology 2 (SH2) domain found in the Nck family; Nck proteins are adaptors that modulate actin cytoskeleton dynamics by linking proline-rich effector molecules to tyrosine kinases or phosphorylated signaling intermediates. There are two members known in this family: Nck1 (Nckalpha) and Nck2 (Nckbeta and Growth factor receptor-bound protein 4 (Grb4)). They are characterized by having 3 SH3 domains and a C-terminal SH2 domain. Nck1 and Nck2 have overlapping functions as determined by gene knockouts. Both bind receptor tyrosine kinases and other tyrosine-phosphorylated proteins through their SH2 domains. In addition they also bind distinct targets. Neuronal signaling proteins: EphrinB1, EphrinB2, and Disabled-1 (Dab-1) all bind to Nck-2 exclusively. And in the case of PDGFR, Tyr(P)751 binds to Nck1 while Tyr(P)1009 binds to Nck2. Nck1 and Nck2 have a role in the infection process of enteropathogenic Escherichia coli (EPEC). Their SH3 domains are involved in recruiting and activating the N-WASP/Arp2/3 complex inducing actin polymerization resulting in the production of pedestals, dynamic bacteria-presenting protrusions of the plasma membrane. A similar thing occurs in the vaccinia virus where motile plasma membrane projections are formed beneath the virus. Recently it has been shown that the SH2 domains of both Nck1 and Nck2 bind the G-protein coupled receptor kinase-interacting protein 1 (GIT1) in a phosphorylation-dependent manner. 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 157819323  35 WYHSNLTRHAAEALLLSNGRDGSYLLRDSNEQTGLYSLSVRAKDSVKHFHVEYTGYSFKFGFNEYSSLKDFVKHFANQPL 114
Cdd:cd09943    3 WYYGRITRHQAETLLNEHGHEGDFLIRDSESNPGDYSVSLKAPGRNKHFKVQVVDNVYCIGQRKFHTMDELVEHYKKAPI 82

                         90
                 ....*....|.
gi 157819323 115 IGSETGTLIVL 125
Cdd:cd09943   83 FTSEQGEKLYL 93

Pleckstrin homology (PH) domain; 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 157819323 167 KEGYLTKQGG-LVKTWKTRWFTLQRNELKYFKDQMSP--EPIRILDLTECSAVQFDYSQDRVNCFCLVFPF-RTFYLCAK 242
Cdd:cd00821    1 KEGYLLKRGGgGLKSWKKRWFVLFEGVLLYYKSKKDSsyKPKGSIPLSGILEVEEVSPKERPHCFELVTPDgRTYYLQAD 80

                         90
                 ....*....|..
gi 157819323 243 TGVEADEWIKIL 254
Cdd:cd00821   81 SEEERQEWLKAL 92

Tandem PH-domain-containing proteins 1 and 2 Pleckstrin homology (PH) domain, C-terminal repeat; The binding of TAPP1 (also called PLEKHA1/pleckstrin homology domain containing, family A (phosphoinositide binding specific) member 1) and TAPP2 (also called PLEKHA2) adaptors to PtdIns(3,4)P(2), but not PI(3,4, 5)P3, function as negative regulators of insulin and PI3K signalling pathways (i.e. TAPP/utrophin/syntrophin complex). TAPP1 and TAPP2 contain two sequential PH domains in which the C-terminal PH domain specifically binds PtdIns(3,4)P2 with high affinity. The N-terminal PH domain does not interact with any phosphoinositide tested. They also contain a C-terminal PDZ-binding motif that interacts with several PDZ-binding proteins, including PTPN13 (known previously as PTPL1 or FAP-1) as well as the scaffolding proteins MUPP1 (multiple PDZ-domain-containing protein 1), syntrophin and utrophin. 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 157819323 167 KEGYLTKQGGLVKTWKTRWFTLQRNELKYFKDQMSPEPIRILDLTECSAVQ---FDYSQDRVNCFCLVFPFRTFYLCAKT 243
Cdd:cd13271   10 KSGYCVKQGAVRKNWKRRFFILDDNTISYYKSETDKEPLRTIPLREVLKVHeclVKSLLMRDNLFEIITTSRTFYIQADS 89

                 ....*....
gi 157819323 244 GVEADEWIK 252
Cdd:cd13271   90 PEEMHSWIK 98

Src homology 2 (SH2) domain found in Nck; Nck proteins are adaptors that modulate actin cytoskeleton dynamics by linking proline-rich effector molecules to tyrosine kinases or phosphorylated signaling intermediates. There are two members known in this family: Nck1 (Nckalpha) and Nck2 (Nckbeta and Growth factor receptor-bound protein 4 (Grb4)). They are characterized by having 3 SH3 domains and a C-terminal SH2 domain. Nck1 and Nck2 have overlapping functions as determined by gene knockouts. Both bind receptor tyrosine kinases and other tyrosine-phosphorylated proteins through their SH2 domains. In addition they also bind distinct targets. Neuronal signaling proteins: EphrinB1, EphrinB2, and Disabled-1 (Dab-1) all bind to Nck-2 exclusively. And in the case of PDGFR, Tyr(P)751 binds to Nck1 while Tyr(P)1009 binds to Nck2. Nck1 and Nck2 have a role in the infection process of enteropathogenic Escherichia coli (EPEC). Their SH3 domains are involved in recruiting and activating the N-WASP/Arp2/3 complex inducing actin polymerization resulting in the production of pedestals, dynamic bacteria-presenting protrusions of the plasma membrane. A similar thing occurs in the vaccinia virus where motile plasma membrane projections are formed beneath the virus. Recently it has been shown that the SH2 domains of both Nck1 and Nck2 bind the G-protein coupled receptor kinase-interacting protein 1 (GIT1) in a phosphorylation-dependent manner. 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 157819323  34 GWYHSNLTRHAAEALLLSNGRDGSYLLRDSNEQTGLYSLSVRAKDSVKHFHVEYTGYSFKFGFNEYSSLKDFVKHFANQP 113
Cdd:cd10409    2 EWYYGNVTRHQAECALNERGVEGDFLIRDSESSPSDFSVSLKAVGKNKHFKVQLVDNVYCIGQRRFNSMDELVEHYKKAP 81

                         90
                 ....*....|....*
gi 157819323 114 LIGSETGTLIVLKHP 128
Cdd:cd10409   82 IFTSEHGEKLYLVKA 96

Src homology 2 (SH2) domain found in Nck; Nck proteins are adaptors that modulate actin cytoskeleton dynamics by linking proline-rich effector molecules to tyrosine kinases or phosphorylated signaling intermediates. There are two members known in this family: Nck1 (Nckalpha) and Nck2 (Nckbeta and Growth factor receptor-bound protein 4 (Grb4)). They are characterized by having 3 SH3 domains and a C-terminal SH2 domain. Nck1 and Nck2 have overlapping functions as determined by gene knockouts. Both bind receptor tyrosine kinases and other tyrosine-phosphorylated proteins through their SH2 domains. In addition they also bind distinct targets. Neuronal signaling proteins: EphrinB1, EphrinB2, and Disabled-1 (Dab-1) all bind to Nck-2 exclusively. And in the case of PDGFR, Tyr(P)751 binds to Nck1 while Tyr(P)1009 binds to Nck2. Nck1 and Nck2 have a role in the infection process of enteropathogenic Escherichia coli (EPEC). Their SH3 domains are involved in recruiting and activating the N-WASP/Arp2/3 complex inducing actin polymerization resulting in the production of pedestals, dynamic bacteria-presenting protrusions of the plasma membrane. A similar thing occurs in the vaccinia virus where motile plasma membrane projections are formed beneath the virus. Recently it has been shown that the SH2 domains of both Nck1 and Nck2 bind the G-protein coupled receptor kinase-interacting protein 1 (GIT1) in a phosphorylation-dependent manner. 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 157819323  35 WYHSNLTRHAAEALLLSNGRDGSYLLRDSNEQTGLYSLSVRAKDSVKHFHVEYTGYSFKFGFNEYSSLKDFVKHFANQPL 114
Cdd:cd10408    3 WYYGKVTRHQAEMALNERGNEGDFLIRDSESSPNDFSVSLKAQGKNKHFKVQLKECVYCIGQRKFSSMEELVEHYKKAPI 82

                         90
                 ....*....|....
gi 157819323 115 IGSETG-TLIVLKH 127
Cdd:cd10408   83 FTSEQGeKLYLIKA 96

ArfGAP with coiled-coil, ankyrin repeat and PH domains Pleckstrin homology (PH) domain; ACAP (also called centaurin beta) functions both as a Rab35 effector and as an Arf6-GTPase-activating protein (GAP) by which it controls actin remodeling and membrane trafficking. ACAP contain an NH2-terminal bin/amphiphysin/Rvs (BAR) domain, a phospholipid-binding domain, a PH domain, a GAP domain, and four ankyrin repeats. The AZAPs constitute a family of Arf GAPs that are characterized by an NH2-terminal pleckstrin homology (PH) domain and a central Arf GAP domain followed by two or more ankyrin repeats. On the basis of sequence and domain organization, the AZAP family is further subdivided into four subfamilies: 1) the ACAPs contain an NH2-terminal bin/amphiphysin/Rvs (BAR) domain (a phospholipid-binding domain that is thought to sense membrane curvature), a single PH domain followed by the GAP domain, and four ankyrin repeats; 2) the ASAPs also contain an NH2-terminal BAR domain, the tandem PH domain/GAP domain, three ankyrin repeats, two proline-rich regions, and a COOH-terminal Src homology 3 domain; 3) the AGAPs contain an NH2-terminal GTPase-like domain (GLD), a split PH domain, and the GAP domain followed by four ankyrin repeats; and 4) the ARAPs contain both an Arf GAP domain and a Rho GAP domain, as well as an NH2-terminal sterile-a motif (SAM), a proline-rich region, a GTPase-binding domain, and five PH domains. PMID 18003747 and 19055940 Centaurin can bind to phosphatidlyinositol (3,4,5)P3. 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 157819323 167 KEGYLTKQ-GGLVKTWKTRWFTLQRNELKYFKDQMSPEP-IRILDLTECSaVQFDYSQDRVNCFCLVFPFRTFYLCAKTG 244
Cdd:cd13250    1 KEGYLFKRsSNAFKTWKRRWFSLQNGQLYYQKRDKKDEPtVMVEDLRLCT-VKPTEDSDRRFCFEVISPTKSYMLQAESE 79

                         90
                 ....*....|.
gi 157819323 245 VEADEWIKILR 255
Cdd:cd13250   80 EDRQAWIQAIQ 90

Arabidopsis thaliana Pleckstrin homolog (PH) 1 (AtPH1) PH domain; AtPH1 is expressed in all plant tissue and is proposed to be the plant homolog of human pleckstrin. Pleckstrin consists of two PH domains separated by a linker region, while AtPH has a single PH domain with a short N-terminal extension. AtPH1 binds PtdIns3P specifically and is thought to be an adaptor molecule since it has no obvious catalytic functions. 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 157819323 167 KEGYLTKQGGLVKTWKTRWFTLQRNELKYFKDQ---MSPEPIRILDLTECSAVQ-FDYSQDRVNCFCLVFPFRTFYLCAK 242
Cdd:cd13276    1 KAGWLEKQGEFIKTWRRRWFVLKQGKLFWFKEPdvtPYSKPRGVIDLSKCLTVKsAEDATNKENAFELSTPEETFYFIAD 80

                 ....*....
gi 157819323 243 TGVEADEWI 251
Cdd:cd13276   81 NEKEKEEWI 89

C-terminal Src homology 2 (C-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 157819323  35 WYHSNLTRHAAEALLLSNGRDGSYLLRDSNEQTGLYSLSVRAKDSVKHFHVEYTGYSFKFGFNEYSSLKDFVKHFANQPL 114
Cdd:cd09932    6 WFHANLTREQAEEMLMRVPRDGAFLVRPSETDPNSFAISFRAEGKIKHCRIKQEGRLFVIGTSQFESLVELVSYYEKHPL 85

                         90
                 ....*....|....
gi 157819323 115 IGSetgtlIVLKHP 128
Cdd:cd09932   86 YRK-----IKLRYP 94

C-terminal Src homology 2 (SH2) domain found in Ras GTPase-activating protein 1 (GAP); RasGAP is part of the GAP1 family of GTPase-activating proteins. The protein is located in the cytoplasm and stimulates the GTPase activity of normal RAS p21, but not its oncogenic counterpart. Acting as a suppressor of RAS function, the protein enhances the weak intrinsic GTPase activity of RAS proteins resulting in RAS inactivation, thereby allowing control of cellular proliferation and differentiation. Mutations leading to changes in the binding sites of either protein are associated with basal cell carcinomas. Alternative splicing results in two isoforms. The shorter isoform which lacks the N-terminal hydrophobic region, has the same activity, and is expressed in placental tissues. In general longer isoform contains 2 SH2 domains, a SH3 domain, a pleckstrin homology (PH) domain, and a calcium-dependent phospholipid-binding C2 domain. The C-terminus contains the catalytic domain of RasGap which catalyzes the activation of Ras by hydrolyzing GTP-bound active Ras into an inactive GDP-bound form of Ras. This model contains the C-terminal 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
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 157819323  35 WYHSNLTRHAAEALLLSNGRDGSYLLRDSNEQTGLYSLSVRAKDSVKHFHVEYTG-YSFKFGFNEYSSLKDFVKHF 109
Cdd:cd10354    2 WFHGKISREEAYNMLVKVGGPGSFLVRESDNTPGDYSLSFRVNEGIKHFKIIPTGnNQFMMGGRYFSSLDDVIDRY 77

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 157819323  35 WYHSNLTRHAAEALLLSNGRDGSYLLRDSNEQTGLYSLSVRAKDSVKHFHVEYTG-YSFKFGFNEYSSLKDFVKHFANQP 113
Cdd:cd10340    2 WFHPVISGIEAENLLKTRGVDGSFLARPSKSNPGDFTLSVRRGDEVTHIKIQNTGdYYDLYGGEKFATLSELVQYYMEQH 81

                         90
                 ....*....|....*.
gi 157819323 114 -LIGSETGTLIVLKHP 128
Cdd:cd10340   82 gQLREKNGDVIELKYP 97

RAS p21 protein activator (GTPase activating protein) 1 Pleckstrin homology (PH) domain; RASA1 (also called RasGap1 or p120) is a member of the RasGAP family of GTPase-activating proteins. RASA1 contains N-terminal SH2-SH3-SH2 domains, followed by two C2 domains, a PH domain, a RasGAP domain, and a BTK domain. Splice variants lack the N-terminal domains. It is a cytosolic vertebrate protein that acts as a suppressor of RAS via its C-terminal GAP domain function, enhancing the weak intrinsic GTPase activity of RAS proteins resulting in the inactive GDP-bound form of RAS, allowing control of cellular proliferation and differentiation. Additionally, it is involved in mitogenic signal transmission towards downstream interacting partners through its N-terminal SH2-SH3-SH2 domains. RASA1 interacts with a number of proteins including: G3BP1, SOCS3, ANXA6, Huntingtin, KHDRBS1, Src, EPHB3, EPH receptor B2, Insulin-like growth factor 1 receptor, PTK2B, DOK1, PDGFRB, HCK, Caveolin 2, DNAJA3, HRAS, GNB2L1 and NCK1. 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 157819323 167 KEGYLTKQGGLVKTWKTRWFTLQRNE--LKYFKDQMSPEPIRILDLTECSAVQFDYS-QDRVNCFCLV---FPFRT-FYL 239
Cdd:cd13260    5 KKGYLLKKGGKNKKWKNLYFVLEGKEqhLYFFDNEKRTKPKGLIDLSYCSLYPVHDSlFGRPNCFQIVvraLNESTiTYL 84

                         90
                 ....*....|....*.
gi 157819323 240 CAKTGVEADEWIKILR 255
Cdd:cd13260   85 CADTAELAQEWMRALR 100

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 157819323  35 WYHSNLTRHAAEaLLLSNGRDGSYLLRDSNEQTGLYSLSVRAKDSVKHFHVEYTGYSFKFGFNE--YSSLKDFVKHFANQ 112
Cdd:cd09935    5 WYHGPISRNAAE-YLLSSGINGSFLVRESESSPGQYSISLRYDGRVYHYRISEDSDGKVYVTQEhrFNTLAELVHHHSKN 83

                         90
                 ....*....|....*.
gi 157819323 113 PligseTGTLIVLKHP 128
Cdd:cd09935   84 A-----DGLITTLRYP 94

Type 2 Diacylglycerol kinase Pleckstrin homology (PH) domain; DGK (also called DAGK) catalyzes the conversion of diacylglycerol (DAG) to phosphatidic acid (PA) utilizing ATP as a source of the phosphate. In non-stimulated cells, DGK activity is low and DAG is used for glycerophospholipid biosynthesis. Upon receptor activation of the phosphoinositide pathway, DGK activity increases which drives the conversion of DAG to PA. DGK acts as a switch by terminating the signalling of one lipid while simultaneously activating signalling by another. There are 9 mammalian DGK isoforms all with conserved catalytic domains and two cysteine rich domains. These are further classified into 5 groups according to the presence of additional functional domains and substrate specificity: Type 1 - DGK-alpha, DGK-beta, DGK-gamma - contain EF-hand motifs and a recoverin homology domain; Type 2 - DGK-delta, DGK-eta, and DGK-kappa- contain a pleckstrin homology domain, two cysteine-rich zinc finger-like structures, and a separated catalytic region; Type 3 - DGK-epsilon - has specificity for arachidonate-containing DAG; Type 4 - DGK-zeta, DGK-iota- contain a MARCKS homology domain, ankyrin repeats, a C-terminal nuclear localization signal, and a PDZ-binding motif; Type 5 - DGK-theta - contains a third cysteine-rich domain, a pleckstrin homology domain and a proline rich region. The type 2 DGKs are present as part of this Metazoan DGK hierarchy. They have a N-terminal PH domain, two cysteine rich domains, followed by bipartite catalytic domains, and a C-terminal SAM domain. Their catalytic domains and perhaps other DGK catalytic domains may function as two independent units in a coordinated fashion. They may also require other motifs for maximal activity because several DGK catalytic domains have very little DAG kinase activity when expressed as isolated subunits. 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 157819323 167 KEGYLTKQGGLVKTWKTRWFTLQRNELKYFKDQMSP--EPIRILDLT--ECSavqfdySQDRVNCFCLVFPFRTFYLCAK 242
Cdd:cd13274    2 KEGPLLKQTSSFQRWKRRYFKLKGRKLYYAKDSKSLifEEIDLSDASvaECS------TKNVNNSFTVITPFRKLILCAE 75

                         90
                 ....*....|...
gi 157819323 243 TGVEADEWIKILR 255
Cdd:cd13274   76 SRKEMEEWISALK 88

Myosin X Pleckstrin homology (PH) domain, repeat 2; MyoX, a MyTH-FERM myosin, is a molecular motor that has crucial functions in the transport and/or tethering of integrins in the actin-based extensions known as filopodia, microtubule binding, and in netrin-mediated axon guidance. It functions as a dimer. MyoX walks on bundles of actin, rather than single filaments, unlike the other unconventional myosins. MyoX is present in organisms ranging from humans to choanoflagellates, but not in Drosophila and Caenorhabditis elegans.MyoX consists of a N-terminal motor/head region, a neck made of 3 IQ motifs, and a tail consisting of a coiled-coil domain, a PEST region, 3 PH domains, a myosin tail homology 4 (MyTH4), and a FERM domain at its very C-terminus. The first PH domain in the MyoX tail is a split-PH domain, interupted by the second PH domain such that PH 1a and PH 1b flanks PH 2. The third PH domain (PH 3) follows the PH 1b domain. This cd contains the second PH repeat. 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 157819323 167 KEGYLTKQGGLV-----KTWKTRWFTLQRNELKYFK-DQMSPEPIRILDLTECSAVqFDYSQDRvNCFCLVFPFRTFYLC 240
Cdd:cd13296    1 KSGWLTKKGGGSstlsrRNWKSRWFVLRDTVLKYYEnDQEGEKLLGTIDIRSAKEI-VDNDPKE-NRLSITTEERTYHLV 78

                         90
                 ....*....|....
gi 157819323 241 AKTGVEADEWIKIL 254
Cdd:cd13296   79 AESPEDASQWVNVL 92

Set binding factor 1 (also called Human MTMR5) Pleckstrin Homology (PH) domain; Sbf1 is a myotubularin-related pseudo-phosphatase. Both Sbf1 and myotubularin interact with the SET domains of Hrx and other epigenetic regulatory proteins, but Sbf1 lacks phosphatase activity due to several amino acid changes in its structurally preserved catalytic pocket. It contains pleckstrin (PH), GEF, and myotubularin homology domains that are thought to be responsible for signaling and growth control. Sbf1 functions as an inhibitor of cellular growth. The N-terminal GEF homology domain serves to inhibit the transforming effects of Sbf1. 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 157819323 166 TKEGYLTKQGGLVKTWKTRWFTLQ--RNELKYFKDQMSPEPIRILDLTECSAVQF--------DYSQDRVNcFCLVFPFR 235
Cdd:cd01235    4 THEGYLYKRGALLKGWKQRWFVLDstKHQLRYYESREDTKCKGFIDLAEVESVTPatpiigapKRADEGAF-FDLKTNKR 82

                         90
                 ....*....|....*.
gi 157819323 236 TFYLCAKTGVEADEWI 251
Cdd:cd01235   83 VYNFCAFDAESAQQWI 98

Grb2-associated binding protein family Pleckstrin homology (PH) domain; Gab proteins are scaffolding adaptor proteins, which possess N-terminal PH domains and a C-terminus with proline-rich regions and multiple phosphorylation sites. Following activation of growth factor receptors, Gab proteins are tyrosine phosphorylated and activate PI3K, which generates 3-phosphoinositide lipids. By binding to these lipids via the PH domain, Gab proteins remain in proximity to the receptor, leading to further signaling. While not all Gab proteins depend on the PH domain for recruitment, it is required for Gab activity. There are 3 families: Gab1, Gab2, and Gab3. 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 157819323 168 EGYLTKQGGLVK----TWKTRWFTLQRNE-------LKYFKDQMSPEPIRILDLTECSAVQ----FDYSQDRVN-CFCLV 231
Cdd:cd13324    4 EGWLTKSPPEKKiwraAWRRRWFVLRSGRlsggqdvLEYYTDDHCKKLKGIIDLDQCEQVDagltFEKKKFKNQfIFDIR 83

                         90       100
                 ....*....|....*....|
gi 157819323 232 FPFRTFYLCAKTGVEADEWI 251
Cdd:cd13324   84 TPKRTYYLVAETEEEMNKWV 103

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
                 ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 157819323  31 QDLGWYHSNLTRHAAEALLLSNGRDGSYLLRDSNeQTGLYSLSVRAKDS----VKHFHVEYT 88
Cdd:cd09934    4 EKYEWYVGDMSRQRAESLLKQEDKEGCFVVRNSS-TKGLYTVSLFTKVPgsphVKHYHIKQN 64

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
                 ....*....|....*....|....*....|....*....|....*....|.
gi 157819323  35 WYHSNLTRHAAEALLLSNGRDGSYLLRDSNEQTGLYSLSVRAKDSVKHFHV 85
Cdd:cd09941    5 WFHGKISRAEAEEILMNQRPDGAFLIRESESSPGDFSLSVKFGNDVQHFKV 55

Src homology 2 (SH2) domain found in the Src oncogene at 42A (Src42); Src42 is a member of the Src non-receptor type tyrosine kinase family of proteins. The integration of receptor tyrosine kinase-induced RAS and Src42 signals by Connector eNhancer of KSR (CNK) as a two-component input is essential for RAF activation in Drosophila. Src42 is present in a wide variety of organisms including: California sea hare, pea aphid, yellow fever mosquito, honey bee, Panamanian leafcutter ant, and sea urchin. Src42 has a unique N-terminal domain, an SH3 domain, an SH2 domain, a kinase domain and a regulatory tail, as do the other members of the family. Like the other members of the Src family the SH2 domain in addition to binding the target, also plays an autoinhibitory role by binding to its C-terminal tail. 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 157819323  35 WYHSNLTRHAAEA-LLLSNGRDGSYLLRDSNEQTGLYSLSVRAKDSVKHFHV---EYTGYsFKFGFNEYSSLKDFVKHFA 110
Cdd:cd10370    5 WYFGKIKRIEAEKkLLLPENEHGAFLIRDSESRHNDYSLSVRDGDTVKHYRIrqlDEGGF-FIARRTTFRTLQELVEHYS 83

                 ...
gi 157819323 111 NQP 113
Cdd:cd10370   84 KDS 86

Src homology 2 (SH2) domain found in SLAM-associated protein (SAP) 1a; 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[VI], 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
                 ....*....|....*....|....*....|....*....|....*....|....
gi 157819323  36 YHSNLTRHAAEALLLSNGRDGSYLLRDSNEQTGLYSLSVRAKDSVKHFHVEYTG 89
Cdd:cd10400    6 YHGKISRETGEKLLLAAGLDGSYLLRDSESVPGVYCLCVLYKGYVYTYRVSQTE 59

Switch-associated protein-70 Pleckstrin homology (PH) domain; SWAP-70 (also called Differentially expressed in FDCP 6/DEF-6 or IRF4-binding protein) functions in cellular signal transduction pathways (in conjunction with Rac), regulates cell motility through actin rearrangement, and contributes to the transformation and invasion activity of mouse embryo fibroblasts. Metazoan SWAP-70 is found in B lymphocytes, mast cells, and in a variety of organs. Metazoan SWAP-70 contains an N-terminal EF-hand motif, a centrally located PH domain, and a C-terminal coiled-coil domain. The PH domain of Metazoan SWAP-70 contains a phosphoinositide-binding site and a nuclear localization signal (NLS), which localize SWAP-70 to the plasma membrane and nucleus, respectively. The NLS is a sequence of four Lys residues located at the N-terminus of the C-terminal a-helix; this is a unique characteristic of the Metazoan SWAP-70 PH domain. The SWAP-70 PH domain binds PtdIns(3,4,5)P3 and PtdIns(4,5)P2 embedded in lipid bilayer vesicles. There are additional plant SWAP70 proteins, but these are not included in this hierarchy. Rice SWAP70 (OsSWAP70) exhibits GEF activity toward the its Rho GTPase, OsRac1, and regulates chitin-induced production of reactive oxygen species and defense gene expression in rice. Arabidopsis SWAP70 (AtSWAP70) plays a role in both PAMP- and effector-triggered immunity. Plant SWAP70 contains both DH and PH domains, but their arrangement is the reverse of that in typical DH-PH-type Rho GEFs, wherein the DH domain is flanked by a C-terminal PH domain. 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 157819323 167 KEGYLTKQGGLVKTWKTRWFTLQRNELKYFKDQMSPEPIRILDLTE-CSAVQFDYSQDRVNCFCLVFPFRTFYLCAKTGV 245
Cdd:cd13273   10 KKGYLWKKGHLLPTWTERWFVLKPNSLSYYKSEDLKEKKGEIALDSnCCVESLPDREGKKCRFLVKTPDKTYELSASDHK 89

                 ....*.
gi 157819323 246 EADEWI 251
Cdd:cd13273   90 TRQEWI 95

Src homology 2 (SH2) domain found in the Src family of non-receptor tyrosine kinases; The Src family kinases are nonreceptor tyrosine kinases that have been implicated in pathways regulating proliferation, angiogenesis, invasion and metastasis, and bone metabolism. It is thought that transforming ability of Src is linked to its ability to activate key signaling molecules in these pathways, rather than through direct activity. As such blocking Src activation has been a target for drug companies. Src family members can be divided into 3 groups based on their expression pattern: 1) Src, Fyn, and Yes; 2) Blk, Fgr, Hck, Lck, and Lyn; and 3) Frk-related kinases Frk/Rak and Iyk/Bsk Of these, cellular c-Src is the best studied and most frequently implicated in oncogenesis. The c-Src contains five distinct regions: a unique N-terminal domain, an SH3 domain, an SH2 domain, a kinase domain and a regulatory tail, as do the other members of the family. Src exists in both active and inactive conformations. Negative regulation occurs through phosphorylation of Tyr, resulting in an intramolecular association between phosphorylated Tyr and the SH2 domain of SRC, which locks the protein in a closed conformation. Further stabilization of the inactive state occurs through interactions between the SH3 domain and a proline-rich stretch of residues within the kinase domain. Conversely, dephosphorylation of Tyr allows SRC to assume an open conformation. Full activity requires additional autophosphorylation of a Tyr residue within the catalytic domain. Loss of the negative-regulatory C-terminal segment has been shown to result in increased activity and transforming potential. Phosphorylation of the C-terminal Tyr residue by C-terminal Src kinase (Csk) and Csk homology kinase results in increased intramolecular interactions and consequent Src inactivation. Specific phosphatases, protein tyrosine phosphatase a (PTPa) and the SH-containing phosphatases SHP1/SHP2, have also been shown to take a part in Src activation. Src is also activated by direct binding of focal adhesion kinase (Fak) and Crk-associated substrate (Cas) to the SH2 domain. SRC activity can also be regulated by numerous receptor tyrosine kinases (RTKs), such as Her2, epidermal growth factor receptor (EGFR), fibroblast growth factor receptor, platelet-derived growth factor receptor (PDGFR), and vascular endothelial growth factor receptor (VEGFR). 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.

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gi 157819323  35 WYHSNLTRHAAEALLLSNGRD-GSYLLRDSNEQTGLYSLSVR-----AKDSVKHF---HVEYTGYSF----KFgfneySS 101
Cdd:cd09933    5 WFFGKIKRKDAEKLLLAPGNPrGTFLIRESETTPGAYSLSVRdgddaRGDTVKHYrirKLDNGGYYIttraTF-----PT 79

                         90
                 ....*....|.
gi 157819323 102 LKDFVKHFANQ 112
Cdd:cd09933   80 LQELVQHYSKD 90

Pleckstrin 2 Pleckstrin homology (PH) domain, repeat 1; Pleckstrin is a protein found in platelets. This name is derived from platelet and leukocyte C kinase substrate and the KSTR string of amino acids. Pleckstrin 2 contains two PH domains and a DEP (dishvelled, egl-10, and pleckstrin) domain. Unlike pleckstrin 1, pleckstrin 2 does not contain obvious sites of PKC phosphorylation. Pleckstrin 2 plays a role in actin rearrangement, large lamellipodia and peripheral ruffle formation, and may help orchestrate cytoskeletal arrangement. The PH domains of pleckstrin 2 are thought to contribute to lamellipodia formation. This cd contains the first PH domain repeat. 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.

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gi 157819323 167 KEGYLTKQGGLVKTWKTRWFTLQRNELKYFKDQMSPEPIRILDLTECSavqfdysqdrVNCFCLVFPFRTF--------- 237
Cdd:cd13301    5 KEGYLVKKGHVVNNWKARWFVLKEDGLEYYKKKTDSSPKGMIPLKGCT----------ITSPCLEYGKRPLvfklttakg 74

                         90
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gi 157819323 238 ---YLCAKTGVEADEWIK 252
Cdd:cd13301   75 qehFFQACSREERDAWAK 92

Src homology 2 domain found in SH2 domain-containing adapter protein E (SHE); SHE is expressed in heart, lung, brain, and skeletal muscle. SHE contains two pTry protein binding domains, protein interaction domain (PID) and a SH2 domain, followed by a glycine-proline rich region, all of which are N-terminal to the phosphotyrosine binding (PTB) 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.

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gi 157819323  35 WYHSNLTRHAAEALLLSnGRDGSYLLRDSNEQTGLYSLSVRAKDSVKHFHVEYT---GYSFKFGFNEYSSLKDFVKHFAN 111
Cdd:cd10391    3 WYHGSISRAEAESRLQP-CKEASYLVRNSESGNSKYSIALKTSQGCVHIIVAQTkdnKYTLNQTSAVFDSIPEVVHYYSN 81

                         90
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gi 157819323 112 Q--PLIGSETGTLIvlkHP 128
Cdd:cd10391   82 EklPFKGAEHMTLL---HP 97

Src homology 2 (SH2) domain in lymphocyte cell kinase (Lck); Lck is a member of the Src non-receptor type tyrosine kinase family of proteins. It is expressed in the brain, T-cells, and NK cells. The unique domain of Lck mediates its interaction with two T-cell surface molecules, CD4 and CD8. It associates with their cytoplasmic tails on CD4 T helper cells and CD8 cytotoxic T cells to assist signaling from the T cell receptor (TCR) complex. When the T cell receptor is engaged by the specific antigen presented by MHC, Lck phosphorylase the intracellular chains of the CD3 and zeta-chains of the TCR complex, allowing ZAP-70 to bind them. Lck then phosphorylates and activates ZAP-70, which in turn phosphorylates Linker of Activated T cells (LAT), a transmembrane protein that serves as a docking site for proteins including: Shc-Grb2-SOS, PI3K, and phospholipase C (PLC). The tyrosine phosphorylation cascade culminates in the intracellular mobilization of a calcium ions and activation of important signaling cascades within the lymphocyte, including the Ras-MEK-ERK pathway, which goes on to activate certain transcription factors such as NFAT, NF-kappaB, and AP-1. These transcription factors regulate the production cytokines such as Interleukin-2 that promote long-term proliferation and differentiation of the activated lymphocytes. The N-terminal tail of Lck is myristoylated and palmitoylated and it tethers the protein to the plasma membrane of the cell. Lck also contains a SH3 domain, a SH2 domain, and a C-terminal tyrosine kinase domain. Lck has 2 phosphorylation sites, the first an autophosphorylation site that is linked to activation of the protein and the second which is phosphorylated by Csk, which inhibits it. Lck is also inhibited by SHP-1 dephosphorylation and by Cbl ubiquitin ligase, which is part of the ubiquitin-mediated pathway. 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.

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gi 157819323  35 WYHSNLTRHAAEALLLSNGR-DGSYLLRDSNEQTGLYSLSVRAKD-----SVKHFHV---EYTGY--SFKFGFNeysSLK 103
Cdd:cd10362    5 WFFKNLSRNDAERQLLAPGNtHGSFLIRESETTAGSFSLSVRDFDqnqgeVVKHYKIrnlDNGGFyiSPRITFP---GLH 81

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gi 157819323 104 DFVKHFAN 111
Cdd:cd10362   82 ELVRHYTN 89

Src homology 2 (SH2) domain found in Tec protein, Bmx; A member of the Tec protein tyrosine kinase Bmx is expressed in the endothelium of large arteries, fetal endocardium, adult endocardium of the left ventricle, bone marrow, lung, testis, granulocytes, myeloid cell lines, and prostate cell lines. Bmx is involved in the regulation of Rho and serum response factor (SRF). Bmx has been shown to interact with PAK1, PTK2, PTPN21, and RUFY1. Most of the Tec family members have a PH domain (Txk and the short (type 1) splice variant of Drosophila Btk29A are exceptions), a Tec homology (TH) domain, a SH3 domain, a SH2 domain, and a protein kinase catalytic domain. The TH domain consists of a Zn2+-binding Btk motif and a proline-rich region. The Btk motif is found in Tec kinases, Ras GAP, and IGBP. It is crucial for the function of Tec PH domains. It is not present in Txk and the type 1 splice form of the Drosophila homolog. The proline-rich regions are highly conserved for the most part with the exception of Bmx whose residues surrounding the PXXP motif are not conserved (TH-like) and Btk29A which is entirely unique with large numbers of glycine residues (TH-extended). Tec family members all lack a C-terminal tyrosine having an autoinhibitory function in its phosphorylated state. 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.

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gi 157819323  32 DLGWYHSNLTRHAAEALLLSNGRDGSYLLRDSNeQTGLYSLSVRA------KDSVKHFHVEYT 88
Cdd:cd10399    5 AYDWFAGNISRSQSEQLLRQKGKEGAFMVRNSS-QVGMYTVSLFSkavndkKGTVKHYHVHTN 66