Src homology 2 (SH2) domain found in B-cell linker (BLNK) protein and SH2 domain-containing leukocyte protein of 76 kDa (SLP-76); BLNK (also known as SLP-65 or BASH) is an important adaptor protein expressed in B-lineage cells. BLNK consists of a N-terminal sterile alpha motif (SAM) domain and a C-terminal SH2 domain. BLNK is a cytoplasmic protein, but a part of it is bound to the plasma membrane through an N-terminal leucine zipper motif and transiently bound to a cytoplasmic domain of Iga through its C-terminal SH2 domain upon B cell antigen receptor (BCR)-stimulation. A non-ITAM phosphotyrosine in Iga is necessary for the binding with the BLNK SH2 domain and/or for normal BLNK function in signaling and B cell activation. Upon phosphorylation BLNK binds Btk and PLCgamma2 through their SH2 domains and mediates PLCgamma2 activation by Btk. BLNK also binds other signaling molecules such as Vav, Grb2, Syk, and HPK1. BLNK has been shown to be necessary for BCR-mediated Ca2+ mobilization, for the activation of mitogen-activated protein kinases such as ERK, JNK, and p38 in a chicken B cell line DT40, and for activation of transcription factors such as NF-AT and NF-kappaB in human or mouse B cells. BLNK is involved in B cell development, B cell survival, activation, proliferation, and T-independent immune responses. BLNK is structurally homologous to SLP-76. SLP-76 and (linker for activation of T cells) LAT are adaptor/linker proteins in T cell antigen receptor activation and T cell development. BLNK interacts with many downstream signaling proteins that interact directly with both SLP-76 and LAT. New data suggest functional complementation of SLP-76 and LAT in T cell antigen receptor function with BLNK in BCR function. 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 47086361 369 DAEEEAGVYKKVWYASGCDRKTAEDALIRSAKDGSFLLRKSSGVDAQQPYTLVVFYNSRVYNIPVRYIASTKQYSLGKEK 448
Cdd:cd09929   1 SAEEEADLLPKEWYAGNIDRKEAEEALRRSNKDGTFLVRDSSGKDSSQPYTLMVLYNDKVYNIQIRFLENTRQYALGTGL 80

                        90       100       110       120
                ....*....|....*....|....*....|....*....|.
gi 47086361 449 QGEERFSSVCDMIENHQKNPLVLVDSLSNTKDSTKLRHAVK 489
Cdd:cd09929  81 RGEETFSSVAEIIEHHQKTPLLLIDGKDNTKDSTCLLYAAG 121

Src homology 2 (SH2) domain found in B-cell linker (BLNK) protein and SH2 domain-containing leukocyte protein of 76 kDa (SLP-76); BLNK (also known as SLP-65 or BASH) is an important adaptor protein expressed in B-lineage cells. BLNK consists of a N-terminal sterile alpha motif (SAM) domain and a C-terminal SH2 domain. BLNK is a cytoplasmic protein, but a part of it is bound to the plasma membrane through an N-terminal leucine zipper motif and transiently bound to a cytoplasmic domain of Iga through its C-terminal SH2 domain upon B cell antigen receptor (BCR)-stimulation. A non-ITAM phosphotyrosine in Iga is necessary for the binding with the BLNK SH2 domain and/or for normal BLNK function in signaling and B cell activation. Upon phosphorylation BLNK binds Btk and PLCgamma2 through their SH2 domains and mediates PLCgamma2 activation by Btk. BLNK also binds other signaling molecules such as Vav, Grb2, Syk, and HPK1. BLNK has been shown to be necessary for BCR-mediated Ca2+ mobilization, for the activation of mitogen-activated protein kinases such as ERK, JNK, and p38 in a chicken B cell line DT40, and for activation of transcription factors such as NF-AT and NF-kappaB in human or mouse B cells. BLNK is involved in B cell development, B cell survival, activation, proliferation, and T-independent immune responses. BLNK is structurally homologous to SLP-76. SLP-76 and (linker for activation of T cells) LAT are adaptor/linker proteins in T cell antigen receptor activation and T cell development. BLNK interacts with many downstream signaling proteins that interact directly with both SLP-76 and LAT. New data suggest functional complementation of SLP-76 and LAT in T cell antigen receptor function with BLNK in BCR function. 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 47086361 369 DAEEEAGVYKKVWYASGCDRKTAEDALIRSAKDGSFLLRKSSGVDAQQPYTLVVFYNSRVYNIPVRYIASTKQYSLGKEK 448
Cdd:cd09929   1 SAEEEADLLPKEWYAGNIDRKEAEEALRRSNKDGTFLVRDSSGKDSSQPYTLMVLYNDKVYNIQIRFLENTRQYALGTGL 80

                        90       100       110       120
                ....*....|....*....|....*....|....*....|.
gi 47086361 449 QGEERFSSVCDMIENHQKNPLVLVDSLSNTKDSTKLRHAVK 489
Cdd:cd09929  81 RGEETFSSVAEIIEHHQKTPLLLIDGKDNTKDSTCLLYAAG 121

SH2 domain;

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 47086361   381 WYASGCDRKTAEDALIRSAKDGSFLLRKSSGVDAQqpYTLVVFYNSRVYNIPVRYIASTKQYSLgkekqGEERFSSVCDM 460
Cdd:pfam00017   1 WYHGKISRQEAERLLLNGKPDGTFLVRESESTPGG--YTLSVRDDGKVKHYKIQSTDNGGYYIS-----GGVKFSSLAEL 73

                  ....
gi 47086361   461 IENH 464
Cdd:pfam00017  74 VEHY 77

Src homology 2 (SH2) domain found in B-cell linker (BLNK) protein and SH2 domain-containing leukocyte protein of 76 kDa (SLP-76); BLNK (also known as SLP-65 or BASH) is an important adaptor protein expressed in B-lineage cells. BLNK consists of a N-terminal sterile alpha motif (SAM) domain and a C-terminal SH2 domain. BLNK is a cytoplasmic protein, but a part of it is bound to the plasma membrane through an N-terminal leucine zipper motif and transiently bound to a cytoplasmic domain of Iga through its C-terminal SH2 domain upon B cell antigen receptor (BCR)-stimulation. A non-ITAM phosphotyrosine in Iga is necessary for the binding with the BLNK SH2 domain and/or for normal BLNK function in signaling and B cell activation. Upon phosphorylation BLNK binds Btk and PLCgamma2 through their SH2 domains and mediates PLCgamma2 activation by Btk. BLNK also binds other signaling molecules such as Vav, Grb2, Syk, and HPK1. BLNK has been shown to be necessary for BCR-mediated Ca2+ mobilization, for the activation of mitogen-activated protein kinases such as ERK, JNK, and p38 in a chicken B cell line DT40, and for activation of transcription factors such as NF-AT and NF-kappaB in human or mouse B cells. BLNK is involved in B cell development, B cell survival, activation, proliferation, and T-independent immune responses. BLNK is structurally homologous to SLP-76. SLP-76 and (linker for activation of T cells) LAT are adaptor/linker proteins in T cell antigen receptor activation and T cell development. BLNK interacts with many downstream signaling proteins that interact directly with both SLP-76 and LAT. New data suggest functional complementation of SLP-76 and LAT in T cell antigen receptor function with BLNK in BCR function. 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 47086361 369 DAEEEAGVYKKVWYASGCDRKTAEDALIRSAKDGSFLLRKSSGVDAQQPYTLVVFYNSRVYNIPVRYIASTKQYSLGKEK 448
Cdd:cd09929   1 SAEEEADLLPKEWYAGNIDRKEAEEALRRSNKDGTFLVRDSSGKDSSQPYTLMVLYNDKVYNIQIRFLENTRQYALGTGL 80

                        90       100       110       120
                ....*....|....*....|....*....|....*....|.
gi 47086361 449 QGEERFSSVCDMIENHQKNPLVLVDSLSNTKDSTKLRHAVK 489
Cdd:cd09929  81 RGEETFSSVAEIIEHHQKTPLLLIDGKDNTKDSTCLLYAAG 121

SH2 domain;

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 47086361   381 WYASGCDRKTAEDALIRSAKDGSFLLRKSSGVDAQqpYTLVVFYNSRVYNIPVRYIASTKQYSLgkekqGEERFSSVCDM 460
Cdd:pfam00017   1 WYHGKISRQEAERLLLNGKPDGTFLVRESESTPGG--YTLSVRDDGKVKHYKIQSTDNGGYYIS-----GGVKFSSLAEL 73

                  ....
gi 47086361   461 IENH 464
Cdd:pfam00017  74 VEHY 77

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

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 47086361 381 WYASGCDRKTAEDALIRSAKDGSFLLRKSSgvdaQQP--YTLVVFYN-SRVYNIPVRYiaSTKQYSLGkekqGEERFSSV 457
Cdd:cd09931   2 WFHGHLSGKEAEKLLLEKGKPGSFLVRESQ----SKPgdFVLSVRTDdDKVTHIMIRC--QGGKYDVG----GGEEFDSL 71

                        90
                ....*....|...
gi 47086361 458 CDMIENHQKNPLV 470
Cdd:cd09931  72 TDLVEHYKKNPMV 84

Src homology 2 (SH2) domain found in Tec-like proteins; The Tec protein tyrosine kinase is the founding member of a family that includes Btk, Itk, Bmx, and Txk. The members have a PH domain, a zinc-binding motif, a SH3 domain, a SH2 domain, and a protein kinase catalytic domain. Btk is involved in B-cell receptor signaling with mutations in Btk responsible for X-linked agammaglobulinemia (XLA) in humans and X-linked immunodeficiency (xid) in mice. Itk is involved in T-cell receptor signaling. Tec is expressed in both T and B cells, and is thought to function in activated and effector T lymphocytes to induce the expression of genes regulated by NFAT transcription factors. In general SH2 domains are involved in signal transduction. They typically bind pTyr-containing ligands via two surface pockets, a pTyr and hydrophobic binding pocket, allowing proteins with SH2 domains to localize to tyrosine phosphorylated sites.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 47086361 381 WYASGCDRKTAEDALIRSAKDGSFLLRKSSGVDAqqpYTLVVFynSRVYNIPVryiasTKQYSLGKEKQGE----ER--F 454
Cdd:cd09934   8 WYVGDMSRQRAESLLKQEDKEGCFVVRNSSTKGL---YTVSLF--TKVPGSPH-----VKHYHIKQNARSEfylaEKhcF 77

                        90       100       110
                ....*....|....*....|....*....|....
gi 47086361 455 SSVCDMIENHQKNPLVLVdslsntkdsTKLRHAV 488
Cdd:cd09934  78 ETIPELINYHQHNSGGLA---------TRLKYPV 102

Src homology 2 (SH2) domain found in Tec protein, Txk; A member of the Tec protein tyrosine kinase Txk is expressed in thymus, spleen, lymph node, T lymphocytes, NK cells, mast cell lines, and myeloid cell line. Txk plays a role in TCR signal transduction, T cell development, and selection which is analogous to the function of Itk. Txk has been shown to interact with IFN-gamma. Unlike most of the Tec family members Txk lacks a PH domain. Instead Txk has a unique region containing a palmitoylated cysteine string which has a similar membrane tethering function as the PH domain. Txk also has a zinc-binding motif, 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 and crucial to the function of the PH domain. It is not present in Txk which is not surprising since it lacks a PH domain. The type 1 splice form of the Drosophila homolog also lacks both the PH domain and the Btk motif. 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.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 47086361 381 WYASGCDRKTAEDALIRSAKDGSFLLRKSSgvdAQQPYTLVVFYNSRVYnipvrYIASTKQYSLGKEKQGE----ER--F 454
Cdd:cd10398   8 WYHKNITRNQAERLLRQESKEGAFIVRDSR---HLGSYTISVFTRARRS-----TEASIKHYQIKKNDSGQwyvaERhlF 79

                        90       100       110
                ....*....|....*....|....*....|....
gi 47086361 455 SSVCDMIENHQKNPLVLVdslsntkdsTKLRHAV 488
Cdd:cd10398  80 QSIPELIQYHQHNAAGLM---------SRLRYPV 104

Src homology 2 (SH2) domain found in feline sarcoma, Fujinami poultry sarcoma, and fes-related (Fes/Fps/Fer) proteins; The Fps family consists of members Fps/Fes and Fer/Flk/Tyk3. They are cytoplasmic protein-tyrosine kinases implicated in signaling downstream from cytokines, growth factors and immune receptors. Fes/Fps/Fer contains three coiled-coil regions, an SH2 (Src-homology-2) and a TK (tyrosine kinase catalytic) domain signature. Members here include: Fps/Fes, Fer, Kin-31, and In general SH2 domains are involved in signal transduction. They typically bind pTyr-containing ligands via two surface pockets, a pTyr and hydrophobic binding pocket, allowing proteins with SH2 domains to localize to tyrosine phosphorylated sites.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 47086361 400 KDGSFLLRKSSGVDAQQP-YTLVVFYNSRVYNIPVRYiASTKQYSLgkEKqgeERFSSVCDMIENHQKN 467
Cdd:cd10361  24 NDGDFLVRKTEPKGGGKRkLVLSVRWDGKIRHFVINR-DDGGKYYI--EG---KSFKSISELINYYQKT 86

Src homology 2 (SH2) domain found in Tec protein, IL2-inducible T-cell kinase (Itk); A member of the Tec protein tyrosine kinase Itk is expressed thymus, spleen, lymph node, T lymphocytes, NK and mast cells. It plays a role in T-cell proliferation and differentiation, analogous to Tec family kinases Txk. Itk has been shown to interact with Fyn, Wiskott-Aldrich syndrome protein, KHDRBS1, PLCG1, Lymphocyte cytosolic protein 2, Linker of activated T cells, Karyopherin alpha 2, Grb2, and Peptidylprolyl isomerase A. 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 and it's lack of presence in Txk is not surprising since it lacks a PH domain. The type 1 splice form of the Drosophila homolog also lacks both the PH domain and the Btk motif. 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.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 47086361 381 WYASGCDRKTAEDALIRSAKDGSFLLRKSSgvdaqQP--YTLVVFYNSRVYNIP-VRYI------ASTKQYSLGkEKQge 451
Cdd:cd10396   8 WYNKNINRSKAEKLLRDEGKEGGFMVRDSS-----QPglYTVSLYTKAGGEGNPcIRHYhiketnDSPKKYYLA-EKH-- 79

                        90       100       110
                ....*....|....*....|....*....|....*..
gi 47086361 452 eRFSSVCDMIENHQKNPLVLVdslsntkdsTKLRHAV 488
Cdd:cd10396  80 -VFNSIPELIEYHKHNAAGLV---------TRLRYPV 106

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.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 47086361 381 WYASGCDRKTAEDALIRSAKDGSFLLRKSSGVDAQQPYTLVVFYNSRV-----YNIpvrYIASTKQYSLGKEKQgeerFS 455
Cdd:cd10399   8 WFAGNISRSQSEQLLRQKGKEGAFMVRNSSQVGMYTVSLFSKAVNDKKgtvkhYHV---HTNAENKLYLAENYC----FD 80

                        90       100       110
                ....*....|....*....|....*....|...
gi 47086361 456 SVCDMIENHQKNPLVLVdslsntkdsTKLRHAV 488
Cdd:cd10399  81 SIPKLIHYHQHNSAGMI---------TRLRHPV 104

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

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 47086361 387 DRKTAEDALI--RSAKDGSFLLRKSSGVDAQqpYTLVVFYNSRV--YNIPVRYIASTKQYSLGKEKQgeerFSSVCDMIE 462
Cdd:cd10341  14 GRDEAEKLLLeyCEGGDGTFLVRESETFVGD--YTLSFWRNGKVqhCRIRSRQENGEKKYYLTDNLV----FDSLYELID 87

                ....*..
gi 47086361 463 NHQKNPL 469
Cdd:cd10341  88 YYRQNPL 94

C-terminal Src homology 2 (cSH2) domain found in p85; Phosphoinositide 3-kinases (PI3Ks) are essential for cell growth, migration, and survival. p110, the catalytic subunit, is composed of an adaptor-binding domain, a Ras-binding domain, a C2 domain, a helical domain, and a kinase domain. The regulatory unit is called p85 and is composed of an SH3 domain, a RhoGap domain, a N-terminal SH2 (nSH2) domain, a inter SH2 (iSH2) domain, and C-terminal (cSH2) domain. There are 2 inhibitory interactions between p110alpha and p85 of P13K: 1) p85 nSH2 domain with the C2, helical, and kinase domains of p110alpha and 2) p85 iSH2 domain with C2 domain of p110alpha. There are 3 inhibitory interactions between p110beta and p85 of P13K: 1) p85 nSH2 domain with the C2, helical, and kinase domains of p110beta, 2) p85 iSH2 domain with C2 domain of p110alpha, and 3) p85 cSH2 domain with the kinase domain of p110alpha. It is interesting to note that p110beta is oncogenic as a wild type protein while p110alpha lacks this ability. One explanation is the idea that the regulation of p110beta by p85 is unique because of the addition of inhibitory contacts from the cSH2 domain and the loss of contacts in the iSH2 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
                ....*....|....*....|....*....|....*....|....*....|.
gi 47086361 379 KVWYASGCDRKTAEDaLIRSAKDGSFLLRKSSGVDaqqPYTLVVFYNSRVY 429
Cdd:cd09930   6 RTWLVGDINRTQAEE-LLRGKPDGTFLIRESSTQG---CYACSVVCNGEVK 52

Src homology 2 (SH2) domain found in suppressor of cytokine signaling (SOCS) proteins; SH2 domain found in SOCS proteins. SOCS was first recognized as a group of cytokine-inducible SH2 (CIS) domain proteins comprising eight family members in human (CIS and SOCS1-SOCS7). In addition to the SH2 domain, SOCS proteins have a variable N-terminal domain and a conserved SOCS box in the C-terminal domain. SOCS proteins bind to a substrate via their SH2 domain. The prototypical members, CIS and SOCS1-SOCS3, have been shown to regulate growth hormone signaling in vitro and in a classic negative feedback response compete for binding at phosphotyrosine sites in JAK kinase and receptor pathways to displace effector proteins and target bound receptors for proteasomal degradation. Loss of SOCS activity results in excessive cytokine signaling associated with a variety of hematopoietic, autoimmune, and inflammatory diseases and certain cancers. Members (SOCS4-SOCS7) were identified by their conserved SOCS box, an adapter motif of 3 helices that associates substrate binding domains, such as the SOCS SH2 domain, ankryin, and WD40 with ubiquitin ligase components. These show limited cytokine induction. In general SH2 domains are involved in signal transduction. They typically bind pTyr-containing ligands via two surface pockets, a pTyr and hydrophobic binding pocket, allowing proteins with SH2 domains to localize to tyrosine phosphorylated sites.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 47086361 370 AEEEAGVYKKVWYASGCDRKTAEDALIrSAKDGSFLLRKSSgvdaQQPYTLVVFYNSRVYNIPVRYIASTKQYSLgKEKQ 449
Cdd:cd10387   1 TEELKKLAKQGWYWGPITRWEAEGKLA-NVPDGSFLVRDSS----DDRYLLSLSFRSHGKTLHTRIEHSNGRFSF-YEQP 74

                        90
                ....*....|....
gi 47086361 450 GEERFSSVCDMIEN 463
Cdd:cd10387  75 DVEGHTSIVDLIEH 88

Src homology 2 (SH2) domain found in the Vav family; Vav proteins are involved in several processes that require cytoskeletal reorganization, such as the formation of the immunological synapse (IS), phagocytosis, platelet aggregation, spreading, and transformation. Vavs function as guanine nucleotide exchange factors (GEFs) for the Rho/Rac family of GTPases. Vav family members have several conserved motifs/domains including: a leucine-rich region, a leucine-zipper, a calponin homology (CH) domain, an acidic domain, a Dbl-homology (DH) domain, a pleckstrin homology (PH) domain, a cysteine-rich domain, 2 SH3 domains, a proline-rich region, and a SH2 domain. Vavs are the only known Rho GEFs that have both the DH/PH motifs and SH2/SH3 domains in the same protein. The leucine-rich helix-loop-helix (HLH) domain is thought to be involved in protein heterodimerization with other HLH proteins and it may function as a negative regulator by forming inactive heterodimers. The CH domain is usually involved in the association with filamentous actin, but in Vav it controls NFAT stimulation, Ca2+ mobilization, and its transforming activity. Acidic domains are involved in protein-protein interactions and contain regulatory tyrosines. The DH domain is a GDP-GTP exchange factor on Rho/Rac GTPases. The PH domain in involved in interactions with GTP-binding proteins, lipids and/or phosphorylated serine/threonine residues. The SH3 domain is involved in localization of proteins to specific sites within the cell interacting with protein with proline-rich sequences. The SH2 domain mediates a high affinity interaction with tyrosine phosphorylated proteins. There are three Vav mammalian family members: Vav1 which is expressed in the hematopoietic system, Vav2 and Vav3 are more ubiquitously expressed. The members here include insect and amphibian Vavs. 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 47086361 381 WYASGCDRKTAEdALIRSAKDGSFLLRKSSGvDAQQpYTLVVFYNSRVYNIPV------RYIASTKQYslgkekqgeerF 454
Cdd:cd09940   7 WFVGEMERDTAE-NRLENRPDGTYLVRVRPQ-GETQ-YALSIKYNGDVKHMKIeqrsdgLYYLSESRH-----------F 72

                        90
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gi 47086361 455 SSVCDMIENHQKNPL 469
Cdd:cd09940  73 KSLVELVNYYERNSL 87