Src kinase-associated phosphoprotein 1 Pleckstrin homology (PH) domain; Adaptor protein Skap1 (also called Skap55/Src kinase-associated phosphoprotein of 55 kDa) and its partner, ADAP (adhesion and degranulation promoting adapter protein) help reorganize the cytoskeleton and/or promote integrin-mediated adhesion upon immunoreceptor activation. Skap1 is also involved in T Cell Receptor (TCR)-induced RapL-Rap1 complex formation and LFA-1 activation. Skap1 has an N-terminal coiled-coil conformation which is proposed to be involved in homodimer formation, a central PH domain and a C-terminal SH3 domain that associates with ADAP. The Skap1 PH domain plays a role in controlling integrin function via recruitment of ADAP-SKAP complexes to integrins as well as in controlling the ability of ADAP to interact with the CBM signalosome and regulate NF-kappaB. SKAP1 is necessary for RapL binding to membranes in a PH domain-dependent manner and the PI3K pathway. Skap adaptor proteins couple receptors to cytoskeletal rearrangements. Skap55/Skap1, Skap2, and Skap-homology (Skap-hom) have an N-terminal coiled-coil conformation, a central PH domain and a C-terminal SH3 domain. Their PH domains bind 3'-phosphoinositides as well as directly affecting targets such as in Skap55 where it directly affecting integrin regulation by ADAP and NF-kappaB activation or in Skap-hom where the dimerization and PH domains comprise a 3'-phosphoinositide-gated molecular switch that controls ruffle formation. 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 295444858 108 VIKQGYLEKKSKDHSFFGSEWQKRWCVISRGLFLYYANEKSKQPKGTFLIKGYSVRMAPHLRKDSKKESCFELISQDRRS 187
Cdd:cd13380    1 ILKQGYLEKRSKDHSFFGSEWQKRWCVLTNRAFYYYASEKSKQPKGGFLIKGYSAQMAPHLRKDSRRDSCFELTTPGRRT 80

                         90       100
                 ....*....|....*....|....*.
gi 295444858 188 YEFTASSPAEARDWVDQISFLLKDLS 213
Cdd:cd13380   81 YQFTAASPSEARDWVDQIQFLLKDTQ 106

Src kinase-associated phosphoprotein 1 Pleckstrin homology (PH) domain; Adaptor protein Skap1 (also called Skap55/Src kinase-associated phosphoprotein of 55 kDa) and its partner, ADAP (adhesion and degranulation promoting adapter protein) help reorganize the cytoskeleton and/or promote integrin-mediated adhesion upon immunoreceptor activation. Skap1 is also involved in T Cell Receptor (TCR)-induced RapL-Rap1 complex formation and LFA-1 activation. Skap1 has an N-terminal coiled-coil conformation which is proposed to be involved in homodimer formation, a central PH domain and a C-terminal SH3 domain that associates with ADAP. The Skap1 PH domain plays a role in controlling integrin function via recruitment of ADAP-SKAP complexes to integrins as well as in controlling the ability of ADAP to interact with the CBM signalosome and regulate NF-kappaB. SKAP1 is necessary for RapL binding to membranes in a PH domain-dependent manner and the PI3K pathway. Skap adaptor proteins couple receptors to cytoskeletal rearrangements. Skap55/Skap1, Skap2, and Skap-homology (Skap-hom) have an N-terminal coiled-coil conformation, a central PH domain and a C-terminal SH3 domain. Their PH domains bind 3'-phosphoinositides as well as directly affecting targets such as in Skap55 where it directly affecting integrin regulation by ADAP and NF-kappaB activation or in Skap-hom where the dimerization and PH domains comprise a 3'-phosphoinositide-gated molecular switch that controls ruffle formation. 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 295444858 108 VIKQGYLEKKSKDHSFFGSEWQKRWCVISRGLFLYYANEKSKQPKGTFLIKGYSVRMAPHLRKDSKKESCFELISQDRRS 187
Cdd:cd13380    1 ILKQGYLEKRSKDHSFFGSEWQKRWCVLTNRAFYYYASEKSKQPKGGFLIKGYSAQMAPHLRKDSRRDSCFELTTPGRRT 80

                         90       100
                 ....*....|....*....|....*.
gi 295444858 188 YEFTASSPAEARDWVDQISFLLKDLS 213
Cdd:cd13380   81 YQFTAASPSEARDWVDQIQFLLKDTQ 106

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 295444858   108 VIKQGYLEKKSKDhsfFGSEWQKRWCVISRGLFLYYANEKSKQ---PKGTFLIKGYSVRMAPHlRKDSKKESCFELISQD 184
Cdd:smart00233   1 VIKEGWLYKKSGG---GKKSWKKRYFVLFNSTLLYYKSKKDKKsykPKGSIDLSGCTVREAPD-PDSSKKPHCFEIKTSD 76

                           90       100
                   ....*....|....*....|....*.
gi 295444858   185 RRSYEFTASSPAEARDWVDQISFLLK 210
Cdd:smart00233  77 RKTLLLQAESEEEREKWVEALRKAIA 102

Src homology 3 domains; Src homology 3 (SH3) domains bind to target proteins through sequences containing proline and hydrophobic amino acids. Pro-containing polypeptides may bind to SH3 domains in 2 different binding orientations.

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|....*
gi 295444858   278 YYQGLWDCHGDQPDELSFQRGDLIRILSKEYNmyGWWVGELNS-VIGIVPKDYLT 331
Cdd:smart00326   4 QVRALYDYTAQDPDELSFKKGDIITVLEKSDD--GWWKGRLGRgKEGLFPSNYVE 56

Src kinase-associated phosphoprotein 1 Pleckstrin homology (PH) domain; Adaptor protein Skap1 (also called Skap55/Src kinase-associated phosphoprotein of 55 kDa) and its partner, ADAP (adhesion and degranulation promoting adapter protein) help reorganize the cytoskeleton and/or promote integrin-mediated adhesion upon immunoreceptor activation. Skap1 is also involved in T Cell Receptor (TCR)-induced RapL-Rap1 complex formation and LFA-1 activation. Skap1 has an N-terminal coiled-coil conformation which is proposed to be involved in homodimer formation, a central PH domain and a C-terminal SH3 domain that associates with ADAP. The Skap1 PH domain plays a role in controlling integrin function via recruitment of ADAP-SKAP complexes to integrins as well as in controlling the ability of ADAP to interact with the CBM signalosome and regulate NF-kappaB. SKAP1 is necessary for RapL binding to membranes in a PH domain-dependent manner and the PI3K pathway. Skap adaptor proteins couple receptors to cytoskeletal rearrangements. Skap55/Skap1, Skap2, and Skap-homology (Skap-hom) have an N-terminal coiled-coil conformation, a central PH domain and a C-terminal SH3 domain. Their PH domains bind 3'-phosphoinositides as well as directly affecting targets such as in Skap55 where it directly affecting integrin regulation by ADAP and NF-kappaB activation or in Skap-hom where the dimerization and PH domains comprise a 3'-phosphoinositide-gated molecular switch that controls ruffle formation. 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 295444858 108 VIKQGYLEKKSKDHSFFGSEWQKRWCVISRGLFLYYANEKSKQPKGTFLIKGYSVRMAPHLRKDSKKESCFELISQDRRS 187
Cdd:cd13380    1 ILKQGYLEKRSKDHSFFGSEWQKRWCVLTNRAFYYYASEKSKQPKGGFLIKGYSAQMAPHLRKDSRRDSCFELTTPGRRT 80

                         90       100
                 ....*....|....*....|....*.
gi 295444858 188 YEFTASSPAEARDWVDQISFLLKDLS 213
Cdd:cd13380   81 YQFTAASPSEARDWVDQIQFLLKDTQ 106

Src kinase-associated phosphoprotein homolog and Skap 2 Pleckstrin homology (PH) domain; Adaptor protein Skap-hom, a homolog of Skap55, which interacts with actin and with ADAP (adhesion and degranulation promoting adapter protein) undergoes tyrosine phosphorylation in response to plating of bone marrow-derived macrophages on fibronectin. Skap-hom has an N-terminal coiled-coil conformation that is involved in homodimer formation, a central PH domain and a C-terminal SH3 domain that associates with ADAP. The Skap-hom PH domain regulates intracellular targeting; its interaction with the DM domain inhibits Skap-hom actin-based ruffles in macrophages and its binding to 3'-phosphoinositides reverses this autoinhibition. The Skap-hom PH domain binds PI[3,4]P2 and PI[3,4,5]P3, but not to PI[3]P, PI[5]P, or PI[4,5]P2. Skap2 is a downstream target of Heat shock transcription factor 4 (HSF4) and functions in the regulation of actin reorganization during lens differentiation. It is thought that SKAP2 anchors the complex of tyrosine kinase adaptor protein 2 (NCK20/focal adhesion to fibroblast growth factor receptors at the lamellipodium in lens epithelial cells. Skap2 has an N-terminal coiled-coil conformation which interacts with the SH2 domain of NCK2, a central PH domain and a C-terminal SH3 domain that associates with ADAP (adhesion and degranulation promoting adapter protein)/FYB (the Fyn binding protein). Skap2 PH domain binds to membrane lipids. Skap adaptor proteins couple receptors to cytoskeletal rearrangements. Src kinase-associated phosphoprotein of 55 kDa (Skap55)/Src kinase-associated phosphoprotein 1 (Skap1), Skap2, and Skap-hom have an N-terminal coiled-coil conformation, a central PH domain and a C-terminal SH3 domain. Their PH domains bind 3'-phosphoinositides as well as directly affecting targets such as in Skap55 where it directly affecting integrin regulation by ADAP and NF-kappaB activation or in Skap-hom where the dimerization and PH domains comprise a 3'-phosphoinositide-gated molecular switch that controls ruffle formation. 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 295444858 108 VIKQGYLEKKSKDHSFFGSEWQKRWCVISRGLFLYYANEKSKQPKGTFLIKGYSVRMAPHLRKDSKKESCFELISQDRRS 187
Cdd:cd13381    1 VLKAGYLEKRRKDHSFFGFEWQKRWCALSNSVFYYYGSDKDKQQKGEFAIDGYDVKMNNTLRKDAKKDCCFEICAPDKRV 80

                         90       100
                 ....*....|....*....|....*
gi 295444858 188 YEFTASSPAEARDWVDQISFLLKDL 212
Cdd:cd13381   81 YQFTAASPKEAEEWVQQIKFILQDL 105

Src Homology 3 domain of Src Kinase-Associated Phosphoprotein 2; SKAP2, also called SKAP55-Related (SKAP55R) or SKAP55 homolog (SKAP-HOM or SKAP55-HOM), is an immune cell-specific adaptor protein that plays an important role in adhesion and migration of B-cells and macrophages. Binding partners include ADAP (adhesion and degranulation-promoting adaptor protein), YopH, SHPS1, and HPK1. SKAP2 has also been identified as a substrate for lymphoid-specific tyrosine phosphatase (Lyp), which has been implicated in a wide variety of autoimmune diseases. It contains a pleckstrin homology (PH) domain, a C-terminal SH3 domain, and several tyrosine phosphorylation sites. Like SKAP1, SKAP2 is expected to bind primarily to a proline-rich region of ADAP through its SH3 domain; its degradation may be regulated by ADAP. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|...
gi 295444858 278 YYQGLWDCHGDQPDELSFQRGDLIRILSKEYNMYGWWVGELNSVIGIVPKDYL 330
Cdd:cd12045    1 FYQGLWDCTGDQPDELSFKRGDTIYILSKEYNRFGWWVGEMKGTIGLVPKAYI 53

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

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 295444858   108 VIKQGYLEKKSKDhsfFGSEWQKRWCVISRGLFLYYANEKSKQ---PKGTFLIKGYSVRMAPHlRKDSKKESCFELISQD 184
Cdd:smart00233   1 VIKEGWLYKKSGG---GKKSWKKRYFVLFNSTLLYYKSKKDKKsykPKGSIDLSGCTVREAPD-PDSSKKPHCFEIKTSD 76

                           90       100
                   ....*....|....*....|....*.
gi 295444858   185 RRSYEFTASSPAEARDWVDQISFLLK 210
Cdd:smart00233  77 RKTLLLQAESEEEREKWVEALRKAIA 102

SH3 domain-binding protein 2 Pleckstrin homology (PH) domain; SH3BP2 (the gene that encodes the adaptor protein 3BP2), HD, ITU, IT10C3, and ADD1 are located near the Huntington's Disease Gene on Human Chromosome 4pl6.3. SH3BP2 lies in a region that is often missing in individuals with Wolf-Hirschhorn syndrome (WHS). Gain of function mutations in SH3BP2 causes enhanced B-cell antigen receptor (BCR)-mediated activation of nuclear factor of activated T cells (NFAT), resulting in a rare, genetic disorder called cherubism. This results in an increase in the signaling complex formation with Syk, phospholipase C-gamma2 (PLC-gamma2), and Vav1. It was recently discovered that Tankyrase regulates 3BP2 stability through ADP-ribosylation and ubiquitylation by the E3-ubiquitin ligase. Cherubism mutations uncouple 3BP2 from Tankyrase-mediated protein destruction, which results in its stabilization and subsequent hyperactivation of the Src, Syk, and Vav signaling pathways. SH3BP2 is also a potential negative regulator of the abl oncogene. 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 295444858 108 VIKQGYLEKKSKDHsFFGSEWQKRWCVISRGLFLYYANEKSKQPKGTFLIKGYSVRMAPHLRkdSKKESCFELI--SQDR 185
Cdd:cd13308    9 VIHSGTLTKKGGSQ-KTLQNWQLRYVIIHQGCVYYYKNDQSAKPKGVFSLNGYNRRAAEERT--SKLKFVFKIIhlSPDH 85

                         90       100
                 ....*....|....*....|
gi 295444858 186 RSYEFTASSPAEARDWVDQI 205
Cdd:cd13308   86 RTWYFAAKSEDEMSEWMEYI 105

Src homology 3 domains; Src homology 3 (SH3) domains bind to target proteins through sequences containing proline and hydrophobic amino acids. Pro-containing polypeptides may bind to SH3 domains in 2 different binding orientations.

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|....*
gi 295444858   278 YYQGLWDCHGDQPDELSFQRGDLIRILSKEYNmyGWWVGELNS-VIGIVPKDYLT 331
Cdd:smart00326   4 QVRALYDYTAQDPDELSFKKGDIITVLEKSDD--GWWKGRLGRgKEGLFPSNYVE 56

Phosphoinositol 3-phosphate binding proteins 1, 2, and 3 pleckstrin homology (PH) domain; PEPP1 (also called PLEKHA4/PH domain-containing family A member 4 and RHOXF1/Rhox homeobox family member 1), and related homologs PEPP2 (also called PLEKHA5/PH domain-containing family A member 5) and PEPP3 (also called PLEKHA6/PH domain-containing family A member 6), have PH domains that interact specifically with PtdIns(3,4)P3. Other proteins that bind PtdIns(3,4)P3 specifically are: TAPP1 (tandem PH-domain-containing protein-1) and TAPP2], PtdIns3P AtPH1, and Ptd- Ins(3,5)P2 (centaurin-beta2). All of these proteins contain at least 5 of the 6 conserved amino acids that make up the putative phosphatidylinositol 3,4,5- trisphosphate-binding motif (PPBM) located at their N-terminus. 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 295444858 105 LDSVIKQGYLEKKSkdhsffGS---EWQKRWCVISRGLFLYYANEKSKQPKGTFLIKGYSVRMAPHLRKDSKKEScFELI 181
Cdd:cd13248    4 NAPVVMSGWLHKQG------GSglkNWRKRWFVLKDNCLYYYKDPEEEKALGSILLPSYTISPAPPSDEISRKFA-FKAE 76

                         90       100
                 ....*....|....*....|....*
gi 295444858 182 SQDRRSYEFTASSPAEARDWVDQIS 206
Cdd:cd13248   77 HANMRTYYFAADTAEEMEQWMNAMS 101

Fungal proteins Pleckstrin homology (PH) domain, repeat 1; The functions of these fungal proteins are unknown, but they all contain 2 PH domains. This cd represents the first 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 295444858 104 ELDSVIKQGYLEKKSKDHSFfgseWQKRWCVISRGLFLYYANEKSKQPKGTF-LIKGYSVrmAPhlRKDSKKESCFELIS 182
Cdd:cd13298    2 EFDRVLKSGYLLKRSRKTKN----WKKRWVVLRPCQLSYYKDEKEYKLRRVInLSELLAV--AP--LKDKKRKNVFGIYT 73

                         90       100
                 ....*....|....*....|...
gi 295444858 183 QDrRSYEFTASSPAEARDWVDQI 205
Cdd:cd13298   74 PS-KNLHFRATSEKDANEWVEAL 95

Sesquipedalian family Pleckstrin homology (PH) domain; The sesquipedalian family has 2 mammalian members: Ses1 and Ses2, which are also callled 7 kDa inositol polyphosphate phosphatase-interacting protein 1 and 2. They play a role in endocytic trafficking and are required for receptor recycling from endosomes, both to the trans-Golgi network and the plasma membrane. Members of this family form homodimers and heterodimers. Sesquipedalian interacts with inositol polyphosphate 5-phosphatase OCRL-1 (INPP5F) also known as Lowe oculocerebrorenal syndrome protein, a phosphatase enzyme that is involved in actin polymerization and is found in the trans-Golgi network and INPP5B. Sesquipedalian contains a single 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 295444858 110 KQGYLEKKSKDHSFFgsewQKRWCVIsRGLFLYYANEK-SKQPKGTFLIKGYSVRMAphlrkDSKKESCFELI--SQDRR 186
Cdd:cd13288   10 KEGYLWKKGERNTSY----QKRWFVL-KGNLLFYFEKKgDREPLGVIVLEGCTVELA-----EDAEPYAFAIRfdGPGAR 79

                         90       100
                 ....*....|....*....|
gi 295444858 187 SYEFTASSPAEARDWVDQIS 206
Cdd:cd13288   80 SYVLAAENQEDMESWMKALS 99

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 295444858  92 DEGIEDilrgaqeldsVIKQGYLEKKSkdHSFfgSEWQKRWCVISRGLFLYYANEKSKQPKGTFLIKGY-SVRMAPhlrk 170
Cdd:cd13273    2 DELILD----------VIKKGYLWKKG--HLL--PTWTERWFVLKPNSLSYYKSEDLKEKKGEIALDSNcCVESLP---- 63

                         90       100       110
                 ....*....|....*....|....*....|....*
gi 295444858 171 DSKKESCFELISQDRRSYEFTASSPAEARDWVDQI 205
Cdd:cd13273   64 DREGKKCRFLVKTPDKTYELSASDHKTRQEWIAAI 98

Src Homology 3 domain of SH3 domain-containing protein 21 (SH3D21) and similar proteins; N-terminal SH3 domain of the uncharacterized protein SH3 domain-containing protein 21, and similar uncharacterized domains, it belongs to the CD2AP-like_3 subfamily of proteins. The CD2AP-like_3 subfamily is composed of the third SH3 domain (SH3C) of CD2AP, CIN85 (Cbl-interacting protein of 85 kDa), and similar domains. CD2AP and CIN85 are adaptor proteins that bind to protein partners and assemble complexes that have been implicated in T cell activation, kidney function, and apoptosis of neuronal cells. They also associate with endocytic proteins, actin cytoskeleton components, and other adaptor proteins involved in receptor tyrosine kinase (RTK) signaling. CD2AP and the main isoform of CIN85 contain three SH3 domains, a proline-rich region, and a C-terminal coiled-coil domain. All of these domains enable CD2AP and CIN85 to bind various protein partners and assemble complexes that have been implicated in many different functions. SH3C of both proteins have been shown to bind to ubiquitin. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|...
gi 295444858 278 YYQGLWDCHGDQPDELSFQRGDLIRILSKEYNMYGWWVGELNSVIGIVPKDYL 330
Cdd:cd12142    1 YCRVLFDYNPVAPDELALKKGDVIEVISKETEDEGWWEGELNGRRGFFPDNFV 53

Pleckstrin homology (PH) domain containing, family H (with MyTH4 domain) members 1 and 2 (PLEKHH1) PH domain, repeat 1; PLEKHH1 and PLEKHH2 (also called PLEKHH1L) are thought to function in phospholipid binding and signal transduction. There are 3 Human PLEKHH genes: PLEKHH1, PLEKHH2, and PLEKHH3. There are many isoforms, the longest of which contain a FERM domain, a MyTH4 domain, two PH domains, a peroximal domain, a vacuolar domain, and a coiled coil stretch. The FERM domain has a cloverleaf tripart structure (FERM_N, FERM_M, FERM_C/N, alpha-, and C-lobe/A-lobe, B-lobe, C-lobe/F1, F2, F3). The C-lobe/F3 within the FERM domain is part of the PH domain family. 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 295444858 110 KQGYLEK---KSKDhsffgseWQKRWCVISRGLFLYYA--NEKSKQPKGTFLIKGYSvRMAPhlrkdSKKESCFELISqD 184
Cdd:cd13282    1 KAGYLTKlggKVKT-------WKRRWFVLKNGELFYYKspNDVIRKPQGQIALDGSC-EIAR-----AEGAQTFEIVT-E 66

                         90       100       110
                 ....*....|....*....|....*....|
gi 295444858 185 RRSYEFTASSPAEARDWVDQISFLLKDLSS 214
Cdd:cd13282   67 KRTYYLTADSENDLDEWIRVIQNVLRRQAS 96

General Receptor for Phosphoinositides-1-like Pleckstrin homology (PH) domain; GRP1/cytohesin3 and the related proteins ARNO (ARF nucleotide-binding site opener)/cytohesin-2 and cytohesin-1 are ARF exchange factors that contain a pleckstrin homology (PH) domain thought to target these proteins to cell membranes through binding polyphosphoinositides. The PH domains of all three proteins exhibit relatively high affinity for PtdIns(3,4,5)P3. Within the Grp1 family, diglycine (2G) and triglycine (3G) splice variants, differing only in the number of glycine residues in the PH domain, strongly influence the affinity and specificity for phosphoinositides. The 2G variants selectively bind PtdIns(3,4,5)P3 with high affinity,the 3G variants bind PtdIns(3,4,5)P3 with about 30-fold lower affinity and require the polybasic region for plasma membrane targeting. These ARF-GEFs share a common, tripartite structure consisting of an N-terminal coiled-coil domain, a central domain with homology to the yeast protein Sec7, a PH domain, and a C-terminal polybasic region. The Sec7 domain is autoinhibited by conserved elements proximal to the PH domain. GRP1 binds to the DNA binding domain of certain nuclear receptors (TRalpha, TRbeta, AR, ER, but not RXR), and can repress thyroid hormone receptor (TR)-mediated transactivation by decreasing TR-complex formation on thyroid hormone response elements. ARNO promotes sequential activation of Arf6, Cdc42 and Rac1 and insulin secretion. Cytohesin acts as a PI 3-kinase effector mediating biological responses including cell spreading and adhesion, chemotaxis, protein trafficking, and cytoskeletal rearrangements, only some of which appear to depend on their ability to activate ARFs. 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 295444858 108 VIKQGYLEKKSKDHSffgsEWQKRWCVISRGLFLYYANEKSKQPKGTFLIKGYSVRMAPhlrkDSKKESCFELIS----- 182
Cdd:cd01252    3 PDREGWLLKLGGRVK----SWKRRWFILTDNCLYYFEYTTDKEPRGIIPLENLSVREVE----DKKKPFCFELYSpsngq 74

                         90       100       110
                 ....*....|....*....|....*....|....*....
gi 295444858 183 --------QDRR-------SYEFTASSPAEARDWVDQIS 206
Cdd:cd01252   75 vikacktdSDGKvvegnhtVYRISAASEEERDEWIKSIK 113

Third Src Homology 3 domain (SH3C) of CD2-associated protein and similar proteins; This subfamily is composed of the third SH3 domain (SH3C) of CD2AP, CIN85 (Cbl-interacting protein of 85 kDa), and similar domains. CD2AP and CIN85 are adaptor proteins that bind to protein partners and assemble complexes that have been implicated in T cell activation, kidney function, and apoptosis of neuronal cells. They also associate with endocytic proteins, actin cytoskeleton components, and other adaptor proteins involved in receptor tyrosine kinase (RTK) signaling. CD2AP and the main isoform of CIN85 contain three SH3 domains, a proline-rich region, and a C-terminal coiled-coil domain. All of these domains enable CD2AP and CIN85 to bind various protein partners and assemble complexes that have been implicated in many different functions. SH3C of both proteins have been shown to bind to ubiquitin. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....
gi 295444858 278 YYQGLWDCHGDQPDELSFQRGDLIRILSKEYNMYGWWVGELNSVIGIVPKDYLT 331
Cdd:cd11875    1 KARVLFDYEAENEDELTLREGDIVTILSKDCEDKGWWKGELNGKRGVFPDNFVE 54

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 295444858 110 KQGYLEKKSKDHSFFG-SEWQKRWCVISRGLFLYYAN-EKSKQPKGTFlikgySVRMAPHLRKDSKKESCFELISQDRrS 187
Cdd:cd13296    1 KSGWLTKKGGGSSTLSrRNWKSRWFVLRDTVLKYYENdQEGEKLLGTI-----DIRSAKEIVDNDPKENRLSITTEER-T 74

                         90
                 ....*....|....*....
gi 295444858 188 YEFTASSPAEARDWVDQIS 206
Cdd:cd13296   75 YHLVAESPEDASQWVNVLT 93

Connector enhancer of KSR (Kinase suppressor of ras) (CNK) pleckstrin homology (PH) domain; CNK family members function as protein scaffolds, regulating the activity and the subcellular localization of RAS activated RAF. There is a single CNK protein present in Drosophila and Caenorhabditis elegans in contrast to mammals which have 3 CNK proteins (CNK1, CNK2, and CNK3). All of the CNK members contain a sterile a motif (SAM), a conserved region in CNK (CRIC) domain, and a PSD-95/DLG-1/ZO-1 (PDZ) domain, and, with the exception of CNK3, a PH domain. A CNK2 splice variant CNK2A also has a PDZ domain-binding motif at its C terminus and Drosophila CNK (D-CNK) also has a domain known as the Raf-interacting region (RIR) that mediates binding of the Drosophila Raf kinase. This cd contains CNKs from mammals, chickens, amphibians, fish, and crustacea. 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 295444858 111 QGYLEKKSKDHSFFGSEWQKRWCVISRGLFLYYANEKSKQPKGTFLIKGYSVRMAphlrKDSKKESCFELISQDRRSYEF 190
Cdd:cd01260   16 QGWLWKKKEAKSFFGQKWKKYWFVLKGSSLYWYSNQQDEKAEGFINLPDFKIERA----SECKKKYAFKACHPKIKTFYF 91

                         90
                 ....*....|....*
gi 295444858 191 TASSPAEARDWVDQI 205
Cdd:cd01260   92 AAENLDDMNKWLSKL 106

Src Homology 3 domain of Mixed Lineage Kinase 4; MLK4 is a Serine/Threonine Kinase (STK), catalyzing the transfer of the gamma-phosphoryl group from ATP to S/T residues on protein substrates. MLKs act as mitogen-activated protein kinase kinase kinases (MAP3Ks, MKKKs, MAPKKKs), which phosphorylate and activate MAPK kinases (MAPKKs or MKKs or MAP2Ks), which in turn phosphorylate and activate MAPKs during signaling cascades that are important in mediating cellular responses to extracellular signals. MLKs play roles in immunity and inflammation, as well as in cell death, proliferation, and cell cycle regulation. The specific function of MLK4 is yet to be determined. Mutations in the kinase domain of MLK4 have been detected in colorectal cancers. MLK4 contains an SH3 domain, a catalytic kinase domain, a leucine zipper, a proline-rich region, and a CRIB domain that mediates binding to GTP-bound Cdc42 and Rac. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*.
gi 295444858 279 YQGLWDCHGDQPDELSFQRGDLIRILSKEYNMY---GWWVGELNSVIGIVPKDYLT 331
Cdd:cd12058    2 WTALYDYEASGEDELSLRRGDVVEVLSQDAAVSgddGWWAGKIRHRLGIFPANYVT 57

Src Homology 3 domain of Nephrocystin (or Nephrocystin-1); Nephrocystin contains an SH3 domain involved in signaling pathways that regulate cell adhesion and cytoskeletal organization. It is a protein that in humans is associated with juvenile nephronophthisis, an inherited kidney disease characterized by renal fibrosis that lead to chronic renal failure in children. It is localized in cell-cell junctions in renal duct cells, and is known to interact with Ack1, an activated Cdc42-associated kinase. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*
gi 295444858 278 YYQGLWDCHGDQPDELSFQRGDLIRILSKEYNmyGWWVGElNSV--IGIVPKDYL 330
Cdd:cd11770    1 LYEALSDFQAEQEGDLSFKKGEVLRIISKRAD--GWWLAE-NSKgnRGLVPKTYL 52

Second Src Homology 3 domain of FCH and double SH3 domains proteins; This group is composed of FCH and double SH3 domains protein 1 (FCHSD1) and FCHSD2. These proteins have a common domain structure consisting of an N-terminal F-BAR (FES-CIP4 Homology and Bin/Amphiphysin/Rvs), two SH3, and C-terminal proline-rich domains. They have only been characterized in silico and their functions remain unknown. This group also includes the insect protein, nervous wreck, which acts as a regulator of synaptic growth signaling. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|.
gi 295444858 278 YYQGLWDCHGDQPDELSFQRGDLIRILSKEYNMY--GWWVGELNSVIGIVP 326
Cdd:cd11762    1 LVRALYDYEAQSDEELSFPEGAIIRILRKDDNGVddGWWEGEFNGRVGVFP 51

Src homology 3 domain of Nitric Oxide Synthase TRaffic INducer; Nostrin is expressed in endothelial and epithelial cells and is involved in the regulation, trafficking and targeting of endothelial NOS (eNOS). It facilitates the endocytosis of eNOS by coordinating the functions of dynamin and the Wiskott-Aldrich syndrome protein (WASP). Increased expression of Nostrin may be correlated to preeclampsia. Nostrin contains an N-terminal F-BAR domain and a C-terminal SH3 domain. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*...
gi 295444858 282 LWDCHGDQPDELSFQRGDLIRILSKEYNmyGWWVGELNSVIGIVPKDY 329
Cdd:cd11823    5 LYSYTANREDELSLQPGDIIEVHEKQDD--GWWLGELNGKKGIFPATY 50

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.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 295444858 106 DSVIKQGYLEKK-SKDHSffgseWQKRWCVISRGLFLYYANEKSKQPKGTFLIKGYSVrMAPHLRKDsKKESCFELISQD 184
Cdd:cd13301    1 PGIIKEGYLVKKgHVVNN-----WKARWFVLKEDGLEYYKKKTDSSPKGMIPLKGCTI-TSPCLEYG-KRPLVFKLTTAK 73

                         90       100       110
                 ....*....|....*....|....*....|
gi 295444858 185 RRSYEFTASSPAEARDWVDQISFLLKDLSS 214
Cdd:cd13301   74 GQEHFFQACSREERDAWAKDITKAITCLEG 103

Tandem PH-domain-containing protein 2 Pleckstrin homology (PH) domain; The binding of 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). TAPP2 contains 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. The members here are most sequence similar to TAPP2 proteins, but may not be actual TAPP2 proteins. 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 295444858 106 DSVIKQGYLEKKSKDHSffgsEWQKRWCVISRGLFLYYANEKSKQpkgtfLIKGYSV----RMAPHLRKdsKKESCFELI 181
Cdd:cd13255    4 EAVLKAGYLEKKGERRK----TWKKRWFVLRPTKLAYYKNDKEYR-----LLRLIDLtdihTCTEVQLK--KHDNTFGIV 72

                         90       100
                 ....*....|....*....|....
gi 295444858 182 SQDRRSYeFTASSPAEARDWVDQI 205
Cdd:cd13255   73 TPARTFY-VQADSKAEMESWISAI 95

Src Homology 3 domain of Mixed Lineage Kinases; MLKs are Serine/Threonine Kinases (STKs), catalyzing the transfer of the gamma-phosphoryl group from ATP to S/T residues on protein substrates. MLKs act as mitogen-activated protein kinase kinase kinases (MAP3Ks, MKKKs, MAPKKKs), which phosphorylate and activate MAPK kinases (MAPKKs or MKKs or MAP2Ks), which in turn phosphorylate and activate MAPKs during signaling cascades that are important in mediating cellular responses to extracellular signals. MLKs play roles in immunity and inflammation, as well as in cell death, proliferation, and cell cycle regulation. Mammals have four MLKs (MLK1-4), mostly conserved in vertebrates, which contain an SH3 domain, a catalytic kinase domain, a leucine zipper, a proline-rich region, and a CRIB domain that mediates binding to GTP-bound Cdc42 and Rac. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|..
gi 295444858 283 WDCHGDqpDELSFQRGDLIRILSKEYNMYG---WWVGELNSVIGIVPKDYLT 331
Cdd:cd11876    8 YDARGE--DELTLRRGQPVEVLSKDAAVSGdegWWTGKIGDKVGIFPSNYVA 57

Src homology 3 domain of Proline-Serine-Threonine Phosphatase-Interacting Protein 1; PSTPIP1, also called CD2 Binding Protein 1 (CD2BP1), is mainly expressed in hematopoietic cells. It is a binding partner of the cell surface receptor CD2 and PTP-PEST, a tyrosine phosphatase which functions in cell motility and Rac1 regulation. It also plays a role in the activation of the Wiskott-Aldrich syndrome protein (WASP), which couples actin rearrangement and T cell activation. Mutations in the gene encoding PSTPIP1 cause the autoinflammatory disorder known as PAPA (pyogenic sterile arthritis, pyoderma gangrenosum, and acne) syndrome. PSTPIP1 contains an N-terminal F-BAR domain, PEST motifs, and a C-terminal SH3 domain. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|...
gi 295444858 279 YQGLWDCHGDQPDELSFQRGDLIRILSKEYNmyGWWVGELNSVIGIVPKDYLT 331
Cdd:cd11824    2 YSVLYDYTAQEDDELSISKGDVVAVIEKGED--GWWTVERNGQKGLVPGTYLE 52

Src Homology 3 domain of metazoan osteoclast stimulating factor 1; OSTF1, also named OSF or SH3P2, is a signaling protein containing SH3 and ankyrin-repeat domains. It acts through a Src-related pathway to enhance the formation of osteoclasts and bone resorption. It also acts as a negative regulator of cell motility. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....
gi 295444858 279 YQGLWDCHGDQPDELSFQRGDLIRILSKEYNmyGWWVGELNSVIGIVPKDYLTT 332
Cdd:cd11772    2 FRALYDYEAQHPDELSFEEGDLLYISDKSDP--NWWKATCGGKTGLIPSNYVEE 53

Second Src Homology 3 domain of FCH and double SH3 domains protein 2; FCHSD2 has a domain structure consisting of an N-terminal F-BAR (FES-CIP4 Homology and Bin/Amphiphysin/Rvs), two SH3, and C-terminal proline-rich domains. It has only been characterized in silico and its function is unknown. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|
gi 295444858 278 YYQGLWDCHGDQPDELSFQRGDLIRILSKEYNM-YGWWVGELNSVIGIVP 326
Cdd:cd11894    1 FVKALYDYEGQTDDELSFPEGAIIRILNKENQDdDGFWEGEFNGRIGVFP 50

Fifth Src homology 3 domain (or SH3E) of Intersectin-2; Intersectin-2 (ITSN2) is an adaptor protein that functions in exo- and endocytosis, actin cytoskeletal reorganization, and signal transduction. It plays a role in clathrin-coated pit (CCP) formation. It binds to many proteins through its multidomain structure and facilitate the assembly of multimeric complexes. ITSN2 also functions as a specific GEF for Cdc42 activation in epithelial morphogenesis, and is required in mitotic spindle orientation. It exists in alternatively spliced short and long isoforms. The short isoform contains two Eps15 homology domains (EH1 and EH2), a coiled-coil region and five SH3 domains (SH3A-E), while the long isoform, in addition, contains RhoGEF (also called Dbl-homologous or DH), Pleckstrin homology (PH) and C2 domains. The fifth SH3 domain (or SH3E) of ITSN2 is expected to bind protein partners, similar to ITSN1 which has been shown to bind many protein partners including SGIP1, Sos1, dynamin1/2, CIN85, c-Cbl, SHIP2, N-WASP, and synaptojanin-1, among others. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

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gi 295444858 282 LWDCHGDQPDELSFQRGDLIRILSKEYNmyGWWVGELNSVIGIVPKDYL 330
Cdd:cd11996    6 MYDYTANNEDELSFSKGQLINVLNKDDP--DWWQGEINGVTGLFPSNYV 52

Pleckstrin homology (PH) domain; Budding yeast contain two main p21-activated kinases (PAKs), Cla4 and Ste20. The yeast Ste20 protein kinase is involved in pheromone response, though the function of Ste20 mammalian homologs is unknown. Cla4 is involved in budding and cytokinesis and interacts with Cdc42, a GTPase required for polarized cell growth as is Pak. Cla4 and Ste20 kinases share a function in localizing cell growth with respect to the septin ring. They both contain a PH domain, a Cdc42/Rac interactive binding (CRIB) domain, and a C-terminal Protein Kinase catalytic (PKc) 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.

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gi 295444858 108 VIKQGYLekKSKDHSFFGSEWQKRWCVISRGLFLYYANEKSKQPKGTFLIKGYS-VRmaphlRKDSkKESCFELI-SQDR 185
Cdd:cd13279    1 VVKSGWV--SVKEDGLLSFRWSKRYLVLREQSLDFYKNESSSSASLSIPLKDISnVS-----RTDL-KPYCFEIVrKSST 72

                         90       100
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gi 295444858 186 RSYEFTASSPAEARDWVDQI 205
Cdd:cd13279   73 KSIYISVKSDDELYDWMDDI 92

Src Homology 3 (SH3) domain of Inhibitor of ASPP protein (iASPP); iASPP, also called RelA-associated inhibitor (RAI), is an oncoprotein that inhibits the apoptotic transactivation potential of p53. It is upregulated in human breast cancers expressing wild-type p53, in acute leukemias regardless of the p53 mutation status, as well as in ovarian cancer where it is associated with poor patient outcome and chemoresistance. iASPP is also a binding partner and negative regulator of p65RelA, which promotes cell proliferation and inhibits apoptosis; p65RelA has the opposite effect on cell growth compared to the p53 family. It contains a proline-rich region, four ankyrin (ANK) repeats, and an SH3 domain at its C-terminal half. The SH3 domain and the ANK repeats of iASPP contribute to the p53 binding site; they bind to the DNA binding domain of p53. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

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gi 295444858 282 LWDCHGDQPDELSFQRGDLIRILSKEYNMYGWWVGELNSVIGIVPKDYL 330
Cdd:cd11952    6 LWDYSAEFPDELSFKEGDMVTVLRKDGEGTDWWWASLCGREGYVPRNYF 54

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.

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gi 295444858 110 KQGYLEKKSKdhsfFGSEWQKRWCVISRGLFLYYANEK---SKQPKGT-FLIKGYSVRMAphlRKDSKKESCFELISQDR 185
Cdd:cd13276    1 KAGWLEKQGE----FIKTWRRRWFVLKQGKLFWFKEPDvtpYSKPRGViDLSKCLTVKSA---EDATNKENAFELSTPEE 73

                         90       100
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gi 295444858 186 RSYeFTASSPAEARDWVDQI 205
Cdd:cd13276   74 TFY-FIADNEKEKEEWIGAI 92

N-terminal Src homology 3 domain of Growth factor receptor-bound protein 2 (GRB2) and related proteins; This family includes the adaptor protein GRB2 and related proteins including Drosophila melanogaster Downstream of receptor kinase (DRK), Caenorhabditis elegans Sex muscle abnormal protein 5 (Sem-5), GRB2-related adaptor protein (GRAP), GRAP2, and similar proteins. Family members contain an N-terminal SH3 domain, a central SH2 domain, and a C-terminal SH3 domain. GRB2/Sem-5/DRK is a critical signaling molecule that regulates the Ras pathway by linking tyrosine kinases to the Ras guanine nucleotide releasing protein Sos (son of sevenless), which converts Ras to the active GTP-bound state. GRAP2 plays an important role in T cell receptor (TCR) signaling by promoting the formation of the SLP-76:LAT complex, which couples the TCR to the Ras pathway. GRAP acts as a negative regulator of T cell receptor (TCR)-induced lymphocyte proliferation by downregulating the signaling to the Ras/ERK pathway. The N-terminal SH3 domain of GRB2 binds to Sos and Sos-derived proline-rich peptides. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

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gi 295444858 281 GLWDCHGDQPDELSFQRGDLIRILSKEYNMyGWWVGELNSVIGIVPKDYL 330
Cdd:cd11804    4 AKHDFKATAEDELSFKKGSILKVLNMEDDP-NWYKAELDGKEGLIPKNYI 52

Third Src Homology 3 domain (SH3C) of Cbl-interacting protein of 85 kDa; CIN85, also called SH3 domain-containing kinase-binding protein 1 (SH3KBP1) or CD2-binding protein 3 (CD2BP3) or Ruk, is an adaptor protein that is involved in the downregulation of receptor tyrosine kinases by facilitating endocytosis through interaction with endophilin-associated ubiquitin ligase Cbl proteins. It is also important in many other cellular processes including vesicle-mediated transport, cytoskeletal remodelling, apoptosis, cell adhesion and migration, and viral infection, among others. CIN85 exists as multiple variants from alternative splicing; the main variant contains three SH3 domains, a proline-rich region, and a C-terminal coiled-coil domain. All of these domains enable CIN85 to bind various protein partners and assemble complexes that have been implicated in many different functions. This alignment model represents the third SH3 domain (SH3C) of CIN85. SH3C has been shown to bind ubiquitin. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

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gi 295444858 291 DELSFQRGDLIRILSKEYNMYGWWVGELNSVIGIVPKDYL 330
Cdd:cd12057   14 DELTIKEGDIVTLISKDCIDAGWWEGELNGRRGVFPDNFV 53

Fifth Src homology 3 domain (or SH3E) of Intersectin-1; Intersectin-1 (ITSN1) is an adaptor protein that functions in exo- and endocytosis, actin cytoskeletal reorganization, and signal transduction. It plays a role in clathrin-coated pit (CCP) formation. It binds to many proteins through its multidomain structure and facilitate the assembly of multimeric complexes. ITSN1 localizes in membranous organelles, CCPs, the Golgi complex, and may be involved in the cell membrane trafficking system. It exists in alternatively spliced short and long isoforms. The short isoform contains two Eps15 homology domains (EH1 and EH2), a coiled-coil region and five SH3 domains (SH3A-E), while the long isoform, in addition, contains RhoGEF (also called Dbl-homologous or DH), Pleckstrin homology (PH) and C2 domains. The fifth SH3 domain (or SH3E) of ITSN1 has been shown to bind many protein partners including SGIP1, Sos1, dynamin1/2, CIN85, c-Cbl, SHIP2, N-WASP, and synaptojanin-1, among others. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.