The LIM domain of LIM and SH3 Protein (LASP); The LIM domain of LIM and SH3 Protein (LASP): LASP family contains two highly homologous members, LASP-1 and LASP-2. LASP contains a LIM motif at its amino terminus, a src homology 3 (SH3) domains at its C-terminal part, and a nebulin-like region in the middle. LASP-1 and -2 are highly conserved in their LIM, nebulin-like, and SH3 domains ,but differ significantly at their linker regions. Both proteins are ubiquitously expressed and involved in cytoskeletal architecture, especially in the organization of focal adhesions. LASP-1 and LASP-2, are important during early embryo- and fetogenesis and are highly expressed in the central nervous system of the adult. However, only LASP-1 seems to participate significantly in neuronal differentiation and plays an important functional role in migration and proliferation of certain cancer cells while the role of LASP-2 is more structural. The expression of LASP-1 in breast tumors is increased significantly. As in other LIM domains, this domain family is 50-60 amino acids in size and shares two characteristic zinc finger motifs. The two zinc fingers contain eight conserved residues, mostly cysteines and histidines, which coordinately bond to two zinc atoms. LIM domains function as adaptors or scaffolds to support the assembly of multimeric protein.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 1789691067   5 CARCGKVVYPTEKVNCLDKYWHKGCFHCEVCKMALNMNNYKGYEKKPYCNAHY 57
Cdd:cd09447     1 CARCGKTVYPTEKLNCLDKIWHKGCFKCEVCGMTLNMKNYKGYNKKPYCNAHY 53

Nebulin repeat;

                          10        20
                  ....*....|....*....|....*...
gi 1789691067  67 DTPENLRLKQQSELQSQVKYKRDFEESK 94
Cdd:pfam00880   1 DTPEIVHAKKNAKLQSDVKYKEDYEKEK 28

The LIM domain of LIM and SH3 Protein (LASP); The LIM domain of LIM and SH3 Protein (LASP): LASP family contains two highly homologous members, LASP-1 and LASP-2. LASP contains a LIM motif at its amino terminus, a src homology 3 (SH3) domains at its C-terminal part, and a nebulin-like region in the middle. LASP-1 and -2 are highly conserved in their LIM, nebulin-like, and SH3 domains ,but differ significantly at their linker regions. Both proteins are ubiquitously expressed and involved in cytoskeletal architecture, especially in the organization of focal adhesions. LASP-1 and LASP-2, are important during early embryo- and fetogenesis and are highly expressed in the central nervous system of the adult. However, only LASP-1 seems to participate significantly in neuronal differentiation and plays an important functional role in migration and proliferation of certain cancer cells while the role of LASP-2 is more structural. The expression of LASP-1 in breast tumors is increased significantly. As in other LIM domains, this domain family is 50-60 amino acids in size and shares two characteristic zinc finger motifs. The two zinc fingers contain eight conserved residues, mostly cysteines and histidines, which coordinately bond to two zinc atoms. LIM domains function as adaptors or scaffolds to support the assembly of multimeric protein.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 1789691067   5 CARCGKVVYPTEKVNCLDKYWHKGCFHCEVCKMALNMNNYKGYEKKPYCNAHY 57
Cdd:cd09447     1 CARCGKTVYPTEKLNCLDKIWHKGCFKCEVCGMTLNMKNYKGYNKKPYCNAHY 53

Variant SH3 domain;

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 1789691067 248 AMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGtvQRTGRTGMLPANYIE 298
Cdd:pfam14604   1 ALYPYEPKDDDELSLQRGDVITVIEESEDGWWEG--INTGRTGLVPANYVE 49

LIM domain; This family represents two copies of the LIM structural domain.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 1789691067   5 CARCGKVVYPTEKVNCLDKYWHKGCFHCEVCKMALNMNNYKGYEKKPYCNAHY 57
Cdd:pfam00412   1 CAGCNRPIYDRELVRALGKVWHPECFRCAVCGKPLTTGDFYEKDGKLYCKHDY 53

Nebulin repeat;

                          10        20
                  ....*....|....*....|....*...
gi 1789691067 103 DTPELQRLKRTQEQISNVKYHEDFEKTK 130
Cdd:pfam00880   1 DTPEIVHAKKNAKLQSDVKYKEDYEKEK 28

The Nebulin repeat is present also in Las1; Tandem arrays of these repeats are known to bind actin.

                           10        20        30
                   ....*....|....*....|....*....|.
gi 1789691067   62 FTTVADTPENLRLKQQSELQSQVKYKRDFEE 92
Cdd:smart00227   1 YTSVPDTPEILLAKKNQKLISDVKYKEDYEK 31

The LIM domain of LIM and SH3 Protein (LASP); The LIM domain of LIM and SH3 Protein (LASP): LASP family contains two highly homologous members, LASP-1 and LASP-2. LASP contains a LIM motif at its amino terminus, a src homology 3 (SH3) domains at its C-terminal part, and a nebulin-like region in the middle. LASP-1 and -2 are highly conserved in their LIM, nebulin-like, and SH3 domains ,but differ significantly at their linker regions. Both proteins are ubiquitously expressed and involved in cytoskeletal architecture, especially in the organization of focal adhesions. LASP-1 and LASP-2, are important during early embryo- and fetogenesis and are highly expressed in the central nervous system of the adult. However, only LASP-1 seems to participate significantly in neuronal differentiation and plays an important functional role in migration and proliferation of certain cancer cells while the role of LASP-2 is more structural. The expression of LASP-1 in breast tumors is increased significantly. As in other LIM domains, this domain family is 50-60 amino acids in size and shares two characteristic zinc finger motifs. The two zinc fingers contain eight conserved residues, mostly cysteines and histidines, which coordinately bond to two zinc atoms. LIM domains function as adaptors or scaffolds to support the assembly of multimeric protein.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 1789691067   5 CARCGKVVYPTEKVNCLDKYWHKGCFHCEVCKMALNMNNYKGYEKKPYCNAHY 57
Cdd:cd09447     1 CARCGKTVYPTEKLNCLDKIWHKGCFKCEVCGMTLNMKNYKGYNKKPYCNAHY 53

C-terminal Src Homology 3 domain of the Nebulin family of proteins; Nebulin family proteins contain multiple nebulin repeats, and may contain an N-terminal LIM domain and/or a C-terminal SH3 domain. They have molecular weights ranging from 34 to 900 kD, depending on the number of nebulin repeats, and they all bind actin. They are involved in the regulation of actin filament architecture and function as stabilizers and scaffolds for cytoskeletal structures with which they associate, such as long actin filaments or focal adhesions. Nebulin family proteins that contain a C-terminal SH3 domain include the giant filamentous protein nebulin, nebulette, Lasp1, and Lasp2. Lasp2, also called LIM-nebulette, is an alternatively spliced variant of nebulette. 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 1789691067 245 TYRAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQRTGRTGMLPANYIE 298
Cdd:cd11789     1 RYRAMYDYAAADDDEVSFQEGDVIINVEIIDDGWMEGTVQRTGQSGMLPANYVE 54

C-terminal Src Homology 3 domain of LIM and SH3 domain protein 1; Lasp1 is a cytoplasmic protein that binds focal adhesion proteins and is involved in cell signaling, migration, and proliferation. It is overexpressed in several cancer cells including breast, ovarian, bladder, and liver. In cancer cells, it can be found in the nucleus; its degree of nuclear localization correlates with tumor size and poor prognosis. Lasp1 is a 36kD protein containing an N-terminal LIM domain, two nebulin repeats, 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 1789691067 244 RTYRAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQRTGRTGMLPANYIE 298
Cdd:cd11934     3 KRYRAVYDYNAADEDEVSFQDGDTIVNVQQIDDGWMYGTVERTGDTGMLPANYVE 57

The LIM domain of Mical (molecule interacting with CasL) like family; The LIM domain of Mical (molecule interacting with CasL) like family: Known members of this family includes LIM domain containing proteins; Mical (molecule interacting with CasL), pollen specific protein SF3, Eplin, xin actin-binding repeat-containing protein 2 (XIRP2) and Ltd-1. The members of this family function mainly at the cytoskeleton and focal adhesions. They interact with transcription factors or other signaling molecules to play roles in muscle development, neuronal differentiation, cell growth and mobility. Eplin has also found to be tumor suppressor. As in other LIM domains, this domain family is 50-60 amino acids in size and shares two characteristic zinc finger motifs.. The two zinc fingers contain eight conserved residues, mostly cysteines and histidines, which coordinately bond to two zinc atoms. LIM domains function as adaptors or scaffolds to support the assembly of multimeric protein.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 1789691067   5 CARCGKVVYPTEKVNCLDKYWHKGCFHCEVCKMALNMNNYKGYEKKPYCNAHY 57
Cdd:cd09358     1 CAVCGKTVYPMERLVADGKLFHKSCFRCSHCNKTLRLGNYASLEGKLYCKPHF 53

Src homology 3 domain of Cortactin and related proteins; This subfamily includes cortactin, Abp1 (actin-binding protein 1), hematopoietic lineage cell-specific protein 1 (HS1), and similar proteins. These proteins are involved in regulating actin dynamics through direct or indirect interaction with the Arp2/3 complex, which is required to initiate actin polymerization. They all contain at least one C-terminal SH3 domain. Cortactin and HS1 bind Arp2/3 and actin through an N-terminal region that contains an acidic domain and several copies of a repeat domain found in cortactin and HS1. Abp1 binds actin via an N-terminal actin-depolymerizing factor (ADF) homology domain. Yeast Abp1 binds Arp2/3 directly through two acidic domains. Mammalian Abp1 does not directly interact with Arp2/3; instead, it regulates actin dynamics indirectly by interacting with dynamin and WASP family proteins. The C-terminal region of these proteins acts as an adaptor or scaffold that can connect membrane trafficking and signaling proteins that bind the SH3 domain within the actin network. 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 1789691067 247 RAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGtVQRTGRTGMLPANYIE 298
Cdd:cd11819     3 KALYDYQAAEDNEISFVEGDIITQIEQIDEGWWLG-VNAKGQKGLFPANYVE 53

Src Homology 3 domain superfamily; Src Homology 3 (SH3) domains are protein interaction domains that bind proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. Thus, they are referred to as proline-recognition domains (PRDs). SH3 domains are less selective and show more diverse specificity compared to other PRDs. They have been shown to bind peptide sequences that lack the PxxP motif; examples include the PxxDY motif of Eps8 and the RKxxYxxY sequence in SKAP55. SH3 domain containing proteins 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, among others. Many members of this superfamily are adaptor proteins that associate with a number of protein partners, facilitating complex formation and signal transduction.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|..
gi 1789691067 245 TYRAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQRtGRTGMLPANY 296
Cdd:cd00174     1 YARALYDYEAQDDDELSFKKGDIITVLEKDDDGWWEGELNG-GREGLFPANY 51

Variant SH3 domain;

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 1789691067 248 AMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGtvQRTGRTGMLPANYIE 298
Cdd:pfam14604   1 ALYPYEPKDDDELSLQRGDVITVIEESEDGWWEG--INTGRTGLVPANYVE 49

Third (or C-terminal) Src Homology 3 domain of Sorbin and SH3 domain containing (Sorbs) proteins and similar domains; This family, also called the vinexin family, is composed predominantly of adaptor proteins containing one sorbin homology (SoHo) and three SH3 domains. Members include the third SH3 domains of Sorbs1 (or ponsin), Sorbs2 (or ArgBP2), Vinexin (or Sorbs3), and similar domains. They are involved in the regulation of cytoskeletal organization, cell adhesion, and growth factor signaling. Members of this family bind multiple partners including signaling molecules like c-Abl, c-Arg, Sos, and c-Cbl, as well as cytoskeletal molecules such as vinculin and afadin. They may have overlapping functions. 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 1789691067 246 YRAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQRTGRTGMLPANYIE 298
Cdd:cd11780     2 YRALYSYTPQNEDELELREGDIVYVMEKCDDGWFVGTSERTGLFGTFPGNYVA 54

Third (or C-terminal) Src Homology 3 domain of Sorbin and SH3 domain containing 1 (Sorbs1), also called ponsin; Sorbs1 is also called ponsin, SH3P12, or CAP (c-Cbl associated protein). It is an adaptor protein containing one sorbin homology (SoHo) and three SH3 domains. It binds Cbl and plays a major role in regulating the insulin signaling pathway by enhancing insulin-induced phosphorylation of Cbl. Sorbs1, like vinexin, localizes at cell-ECM and cell-cell adhesion sites where it binds vinculin, paxillin, and afadin. It may function in the control of cell motility. Other interaction partners of Sorbs1 include c-Abl, Sos, flotillin, Grb4, ataxin-7, filamin C, 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.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*.
gi 1789691067 245 TYRAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQRTGRTGMLPANYIEFV 300
Cdd:cd11916     3 SYQALYSYAPQNDDELELRDGDIVDVMEKCDDGWFVGTSRRTKQFGTFPGNYVKLL 58

Src homology 3 domain of Cortactin; Cortactin was originally identified as a substrate of Src kinase. It is an actin regulatory protein that binds to the Arp2/3 complex and stabilizes branched actin filaments. It is involved in cellular processes that affect cell motility, adhesion, migration, endocytosis, and invasion. It is expressed ubiquitously except in hematopoietic cells, where the homolog hematopoietic lineage cell-specific 1 (HS1) is expressed instead. Cortactin contains an N-terminal acidic domain, several copies of a repeat domain found in cortactin and HS1, a proline-rich region, and a C-terminal SH3 domain. The N-terminal region interacts with the Arp2/3 complex and F-actin, and is crucial in regulating branched actin assembly. Cortactin also serves as a scaffold and provides a bridge to the actin cytoskeleton for membrane trafficking and signaling proteins that bind to its SH3 domain. Binding partners for the SH3 domain of cortactin include dynamin2, N-WASp, MIM, FGD1, 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.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 1789691067 248 AMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQrtGRTGMLPANYIE 298
Cdd:cd11959     4 ALYDYQAADDDEISFDPDDIITNIEMIDEGWWRGVCR--GKYGLFPANYVE 52

The LIM domains of thymus LIM protein (TLP); The LIM domain of thymus LIM protein (TLP) like proteins: This family includes the LIM domains of TLP and CRIP (Cysteine-Rich Intestinal Protein). TLP is the distant member of the CRP family of proteins. TLP has two isomers (TLP-A and TLP-B) and sharing approximately 30% with each of the three other CRPs. Like CRP1, CRP2 and CRP3/MLP, TLP has two LIM domains, connected by a flexible linker region. Unlike the CRPs, TLP lacks the nuclear targeting signal (K/R-K/R-Y-G-P-K) and is localized solely in the cytoplasm. TLP is specifically expressed in the thymus in a subset of cortical epithelial cells. TLP has a role in development of normal thymus and in controlling the development and differentiation of thymic epithelial cells. CRIP is a short LIM protein with only one LIM domain. CRIP gene is developmentally regulated and can be induced by glucocorticoid hormones during the first three postnatal weeks. The domain shows close sequence homology to LIM domain of thymus LIM protein. However, unlike the TLP proteins which have two LIM domains, the members of this family have only one LIM domain. LIM domains are 50-60 amino acids in size and share two characteristic zinc finger motifs. The two zinc fingers contain eight conserved residues, mostly cysteines and histidines, which coordinately bond to two zinc atoms. LIM domains function as adaptors or scaffolds to support the assembly of multimeric protein complexes.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 1789691067   5 CARCGKVVYPTEKVNCLDKYWHKGCFHCEVCKMALNMNNYKGYEKKPYCNAHY 57
Cdd:cd09401     1 CPKCGKPVYFAEKKTSLGRDWHKPCLRCEKCKKTLTPGQHSEHEGKPYCNKCY 53

Third (or C-terminal) Src Homology 3 domain of Vinexin, also called Sorbin and SH3 domain containing 3 (Sorbs3); Vinexin is also called Sorbs3, SH3P3, and SH3-containing adapter molecule 1 (SCAM-1). It is an adaptor protein containing one sorbin homology (SoHo) and three SH3 domains. Vinexin was first identified as a vinculin binding protein; it is co-localized with vinculin at cell-ECM and cell-cell adhesion sites. There are several splice variants of vinexin: alpha, which contains the SoHo and three SH3 domains and displays tissue-specific expression; and beta, which contains only the three SH3 domains and is widely expressed. Vinexin alpha stimulates the accumulation of F-actin at focal contact sites. Vinexin also promotes keratinocyte migration and wound healing. The SH3 domains of vinexin have been reported to bind a number of ligands including vinculin, WAVE2, DLG5, Abl, and Cbl. 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 1789691067 246 YRAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQRTGRTGMLPANYI 297
Cdd:cd11918     4 YKAVYQYRPQNEDELELREGDRVDVMQQCDDGWFVGVSRRTQKFGTFPGNYV 55

First Src Homology 3 domain (SH3A) of CD2-associated protein and similar proteins; This subfamily is composed of the first SH3 domain (SH3A) 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. SH3A of both proteins bind to an atypical PXXXPR motif at the C-terminus of Cbl and the cytoplasmic domain of the cell adhesion protein CD2. CIN85 SH3A binds to internal proline-rich motifs within the proline-rich region; this intramolecular interaction serves as a regulatory mechanism to keep CIN85 in a closed conformation, preventing the recruitment of other proteins. CIN85 SH3A has also 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.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....
gi 1789691067 245 TYRAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQrtGRTGMLPANYIE 298
Cdd:cd11873     1 EVIVEFDYDAEEPDELTLKVGDIITNVKKMEEGWWEGTLN--GKRGMFPDNFVK 52

Src homology 3 domain of Protein kinase C and Casein kinase Substrate in Neurons (PACSIN) proteins; PACSINs, also called Synaptic dynamin-associated proteins (Syndapins), act as regulators of cytoskeletal and membrane dynamics. They bind both dynamin and Wiskott-Aldrich syndrome protein (WASP), and may provide direct links between the actin cytoskeletal machinery through WASP and dynamin-dependent endocytosis. Vetebrates harbor three isoforms with distinct expression patterns and specific functions. PACSINs contain 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        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 1789691067 247 RAMYDYSAQDEDEVSFRDGDYIVNVQPIDD-GWMYGtvQRTGRTGMLPANYIE 298
Cdd:cd11843     3 RALYDYEGQESDELSFKAGDILTKLEEEDEqGWCKG--RLDGRVGLYPANYVE 53

Src homology 3 domain of Abl Interactor proteins; Abl interactor (Abi) proteins are adaptor proteins serving as binding partners and substrates of Abl tyrosine kinases. They are involved in regulating actin cytoskeletal reorganization and play important roles in membrane-ruffling, endocytosis, cell motility, and cell migration. They localize to sites of actin polymerization in epithelial adherens junction and immune synapses, as well as to the leading edge of lamellipodia. Vertebrates contain two Abi proteins, Abi1 and Abi2. Abi1 displays a wide expression pattern while Abi2 is highly expressed in the eye and brain. Abi proteins contain a homeobox homology domain, a proline-rich region, and a SH3 domain. The SH3 domain of Abi binds to a PxxP motif in Abl. 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 1789691067 247 RAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQrtGRTGMLPANYIE 298
Cdd:cd11826     3 VALYDYTADKDDELSFQEGDIIYVTKKNDDGWYEGVLN--GVTGLFPGNYVE 52

The LIM domain of LIM and transglutaminase domains protein (Ltd-1); The LIM domain of LIM and transglutaminase domains protein (Ltd-1): This family includes mouse Ky protein and Caenorhabditis elegans Ltd-1 protein. The members of this family consists a N-terminal Lim domain and a C-terminal transglutaminase domain. The mouse Ky protein has putative function in muscle development. The mouse with ky mutant exhibits combined posterior and lateral curvature of the spine. The Ltd-1 gene in C. elegans is expressed in developing hypodermal cells from the twofold stage embryo through adulthood. These data define the ltd-1 gene as a novel marker for C. elegans epithelial cell development. As in other LIM domains, this domain family is 50-60 amino acids in size and shares two characteristic zinc finger motifs. The two zinc fingers contain eight conserved residues, mostly cysteines and histidines, which coordinately bond to two zinc atoms. LIM domains function as adaptors or scaffolds to support the assembly of multimeric protein.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....
gi 1789691067   5 CARCGKVVYPTEKVNCLDKYWHKGCFHCEVCKMALNMNNYKGY--EKKPYCNAH 56
Cdd:cd09443     1 CPRCGKTAYPAESVDKDGTFYHKGCFKCRECGTRLSLKTFTFVqgDGEVYCARH 54

Src Homology 3 domain of Pak Interactive eXchange factors; PIX proteins are Rho guanine nucleotide exchange factors (GEFs), which activate small GTPases by exchanging bound GDP for free GTP. They act as GEFs for both Cdc42 and Rac 1, and have been implicated in cell motility, adhesion, neurite outgrowth, and cell polarity. Vertebrates contain two proteins from the PIX subfamily, alpha-PIX and beta-PIX. Alpha-PIX, also called ARHGEF6, is localized in dendritic spines where it regulates spine morphogenesis. Mutations in the ARHGEF6 gene cause X-linked intellectual disability in humans. Beta-PIX play roles in regulating neuroendocrine exocytosis, focal adhesion maturation, cell migration, synaptic vesicle localization, and insulin secretion. PIX proteins contain an N-terminal SH3 domain followed by RhoGEF (also called Dbl-homologous or DH) and Pleckstrin Homology (PH) domains, and a C-terminal leucine-zipper domain for dimerization. The SH3 domain of PIX binds to an atypical PxxxPR motif in p21-activated kinases (PAKs) with high affinity. The binding of PAKs to PIX facilitate the localization of PAKs to focal complexes and also localizes PAKs to PIX targets Cdc43 and Rac, leading to the activation of PAKs. 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 1789691067 245 TYRAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQrtGRTGMLPANYIE 298
Cdd:cd11877     1 LVRAKFNFEGTNEDELSFDKGDIITVTQVVEGGWWEGTLN--GKTGWFPSNYVK 52

Src homology 3 domain of Protein kinase C and Casein kinase Substrate in Neurons 3 (PACSIN3); PACSIN 3 or Syndapin III (Synaptic dynamin-associated protein III) is expressed ubiquitously and regulates glucose uptake in adipocytes through its role in GLUT1 trafficking. It also modulates the subcellular localization and stimulus-specific function of the cation channel TRPV4. PACSINs act as regulators of cytoskeletal and membrane dynamics. Vetebrates harbor three isoforms with distinct expression patterns and specific functions. PACSINs contain 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        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 1789691067 247 RAMYDYSAQDEDEVSFRDGDYIVNVQPIDD-GWMYGTVQrTGRTGMLPANYIE 298
Cdd:cd11997     5 RALYDYTGQEADELSFKAGEELLKIGEEDEqGWCKGRLL-SGRIGLYPANYVE 56

Src homology 3 domain of Ubiquitin-associated and SH3 domain-containing protein B; UBASH3B, also called Suppressor of T cell receptor Signaling (STS)-1 or T cell Ubiquitin LigAnd (TULA)-2 is an active phosphatase that is expressed ubiquitously. The phosphatase activity of UBASH3B is essential for its roles in the suppression of TCR signaling and the regulation of EGFR. It also interacts with Syk and functions as a negative regulator of platelet glycoprotein VI signaling. TULA proteins contain an N-terminal UBA domain, a central SH3 domain, and a C-terminal histidine phosphatase domain. They bind c-Cbl through the SH3 domain and to ubiquitin via UBA. 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 1789691067 245 TYRAMYDYSAQDEDEVSFRDGDYI----VNVQPIDDGWMYGTVQRTGRTGMLPANYI 297
Cdd:cd11936     3 TLQVIYPYTPQNDDELELVPGDYIfmspMEQTSTSEGWIYGTSLTTGCSGLLPENYI 59

This domain belongs to the LIM domain family which are found on Mical (molecule interacting with CasL) like proteins; The LIM domain on proteins of unknown function: This domain belongs to the LIM domain family which are found on Mical (molecule interacting with CasL)-like proteins. Known members of the Mical-like family includes single LIM domain containing proteins, Mical (molecule interacting with CasL), pollen specific protein SF3, Eplin, xin actin-binding repeat-containing protein 2 (XIRP2), and Ltd-1. The members of this family function mainly at the cytoskeleton and focal adhesions. They interact with transcription factors or other signaling molecules to play roles in muscle development, neuronal differentiation, cell growth, and mobility. As in other LIM domains, this domain family is 50-60 amino acids in size and shares two characteristic zinc finger motifs. The two zinc fingers contain eight conserved residues, mostly cysteines and histidines, which coordinately bond to two zinc atoms. LIM domains function as adaptors or scaffolds to support the assembly of multimeric protein.

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gi 1789691067   5 CARCGKVVYPTEKVNCLDKYWHKGCFHCEVCKMALNMNNYKGYEKKPYCNAHY 57
Cdd:cd09445     1 CRSCGKPVYKMEEIIAEKHIYHKNCFRCKDCNKQLKVDNYQSHEGNLYCKVHF 53

The LIM domain of Cysteine-Rich Intestinal Protein (CRIP); The LIM domain of Cysteine-Rich Intestinal Protein (CRIP): CRIP is a short protein with only one LIM domain. CRIP gene is developmentally regulated and can be induced by glucocorticoid hormones during the first three postnatal weeks. The domain shows close sequence homology to LIM domain of thymus LIM protein. However, unlike the TLP proteins which have two LIM domains, the members of this family have only one LIM domain. LIM domains are 50-60 amino acids in size and share two characteristic zinc finger motifs. The two zinc fingers contain eight conserved residues, mostly cysteines and histidines, which coordinately bond to two zinc atoms. LIM domains function as adaptors or scaffolds to support the assembly of multimeric protein complexes.

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gi 1789691067   5 CARCGKVVYPTEKVNCLDKYWHKGCFHCEVCKMALNMNNYKGYEKKPYCN 54
Cdd:cd09478     1 CPKCDKEVYFAERVTSLGKDWHRPCLKCEKCGKTLTPGSHAEHDGKPYCN 50

Src homology 3 domain of Protein kinase C and Casein kinase Substrate in Neurons 1 (PACSIN1) and PACSIN 2; PACSIN 1 or Syndapin I (Synaptic dynamin-associated protein I) is expressed specifically in the brain and is localized in neurites and synaptic boutons. It binds the brain-specific proteins dynamin I, synaptojanin, synapsin I, and neural Wiskott-Aldrich syndrome protein (nWASP), and functions as a link between the cytoskeletal machinery and synaptic vesicle endocytosis. PACSIN 1 interacts with huntingtin and may be implicated in the neuropathology of Huntington's disease. PACSIN 2 or Syndapin II is expressed ubiquitously and is involved in the regulation of tubulin polymerization. It associates with Golgi membranes and forms a complex with dynamin II which is crucial in promoting vesicle formation from the trans-Golgi network. PACSINs act as regulators of cytoskeletal and membrane dynamics. Vetebrates harbor three isoforms with distinct expression patterns and specific functions. PACSINs contain 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.

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gi 1789691067 247 RAMYDYSAQDEDEVSFRDGDYIVNVQPIDD-GWMYGTVQrTGRTGMLPANYIE 298
Cdd:cd11998     4 RALYDYDGQEQDELSFKAGDELTKLEDEDEqGWCKGRLD-SGQVGLYPANYVE 55

Third (or C-terminal) Src Homology 3 domain of Sorbin and SH3 domain containing 2 (Sorbs2), also called Arg-binding protein 2 (ArgBP2); Sorbs2 or ArgBP2 is an adaptor protein containing one sorbin homology (SoHo) and three SH3 domains. It regulates actin-dependent processes including cell adhesion, morphology, and migration. It is expressed in many tissues and is abundant in the heart. Like vinexin, it is found in focal adhesion where it interacts with vinculin and afadin. It also localizes in epithelial cell stress fibers and in cardiac muscle cell Z-discs. Sorbs2 has been implicated to play roles in the signaling of c-Arg, Akt, and Pyk2. Other interaction partners of Sorbs2 include c-Abl, flotillin, spectrin, dynamin 1/2, synaptojanin, PTP-PEST, 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 1789691067 246 YRAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQRTGRTGMLPANYIE 298
Cdd:cd11917     7 FQALYNYMPRNEDELELREGDVIDVMEKCDDGWFVGTSRRTKFFGTFPGNYVK 59

C-terminal (Fourth) Src Homology 3 domain of SH3 domain containing ring finger 1 (SH3RF1), SH3RF3, and similar domains; SH3RF1 (or POSH) and SH3RF3 (or POSH2) are scaffold proteins that function as E3 ubiquitin-protein ligases. They contain an N-terminal RING finger domain and four SH3 domains. This model represents the fourth SH3 domain, located at the C-terminus of SH3RF1 and SH3RF3, and similar domains. SH3RF1 plays a role in calcium homeostasis through the control of the ubiquitin domain protein Herp. It may also have a role in regulating death receptor mediated and JNK mediated apoptosis. SH3RF3 interacts with p21-activated kinase 2 (PAK2) and GTP-loaded Rac1. It may play a role in regulating JNK mediated apoptosis in certain conditions. 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 1789691067 246 YRAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQRTGRTGMLPANYIE 298
Cdd:cd11785     2 YRVIVPYPPQSEAELELKEGDIVFVHKKREDGWFKGTLQRTGKTGLFPGSFVE 54

Src homology 3 domain of Myosins Ie, If, and similar proteins; Myosins Ie (MyoIe) and If (MyoIf) are nonmuscle, unconventional, long tailed, class I myosins containing an N-terminal motor domain and a myosin tail with TH1, TH2, and SH3 domains. MyoIe interacts with the endocytic proteins, dynamin and synaptojanin-1, through its SH3 domain; it may play a role in clathrin-dependent endocytosis. In the kidney, MyoIe is critical for podocyte function and normal glomerular filtration. Mutations in MyoIe is associated with focal segmental glomerulosclerosis, a disease characterized by massive proteinuria and progression to end-stage kidney disease. MyoIf is predominantly expressed in the immune system; it plays a role in immune cell motility and innate immunity. Mutations in MyoIf may be associated with the loss of hearing. The MyoIf gene has also been found to be fused to the MLL (Mixed lineage leukemia) gene in infant acute myeloid leukemias (AML). 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 1789691067 247 RAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQrtGRTGMLPANYIE 298
Cdd:cd11827     3 KALYAYDAQDTDELSFNEGDIIEILKEDPSGWWTGRLR--GKEGLFPGNYVE 52

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.

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gi 1789691067 245 TYRAMYDYSAQDEDEVSFRDGD--YIVNVQPIDDGWMYGTVQrtGRTGMLPANYIE 298
Cdd:cd11875     1 KARVLFDYEAENEDELTLREGDivTILSKDCEDKGWWKGELN--GKRGVFPDNFVE 54

C-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 C-terminal SH3 domains (SH3c) of GRB2 and GRAP2 have been shown to bind to classical PxxP motif ligands, as well as to non-classical motifs. GRB2 SH3c binds Gab2 (Grb2-associated binder 2) through epitopes containing RxxK motifs, while the SH3c of GRAP2 binds to the phosphatase-like protein HD-PTP via a RxxxxK motif. SH3 domains are protein interaction domains that typically 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 1789691067 247 RAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQrtGRTGMLPANYIE 298
Cdd:cd11805     3 QALYDFNPQEPGELEFRRGDIITVLDSSDPDWWKGELR--GRVGIFPANYVQ 52

Second Src Homology 3 domain of Bzz1 and similar domains; Bzz1 (or Bzz1p) is a WASP/Las17-interacting protein involved in endocytosis and trafficking to the vacuole. It physically interacts with type I myosins and functions in the early steps of endocytosis. Together with other proteins, it induces membrane scission in yeast. Bzz1 contains an N-terminal F-BAR (FES-CIP4 Homology and Bin/Amphiphysin/Rvs), a central coiled-coil, and two C-terminal SH3 domains. This model represents the second 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.

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gi 1789691067 245 TYRAMYDYSAQDEDEVSFRDGDYIVNVQPID-DGWMYGTVQrtGRTGMLPANY 296
Cdd:cd11778     1 YVEALYDYEAQGDDEISIRVGDRIAVIRGDDgSGWTYGEIN--GVKGLFPTSY 51

The second LIM domain of Cysteine Rich Protein 2 (CRP2); The second LIM domain of Cysteine Rich Protein 2 (CRP2): Cysteine-rich proteins (CRPs) are characterized by the presence of two LIM domains linked to short glycine-rich repeats (GRRs). The CRP family members include CRP1, CRP2, CRP3/MLP and TLPCRP1, CRP2 and CRP3 share a conserved nuclear targeting signal (K/R-K/R-Y-G-P-K), which supports the fact that these proteins function not only in the cytoplasm but also in the nucleus. CRPs control regulatory pathways during cellular differentiation, and involve in complex transcription circuits, and the organization as well as the arrangement of the myofibrillar/cytoskeletal network.CRP3 also called Muscle LIM Protein (MLP), which is a striated muscle-specific factor that enhances myogenic differentiation. The second LIM domain of CRP3/MLP interacts with cytoskeletal protein beta-spectrin. CRP3/MLP also interacts with the basic helix-loop-helix myogenic transcription factors MyoD, myogenin, and MRF4 thereby increasing their affinity for specific DNA regulatory elements. LIM domains are 50-60 amino acids in size and share two characteristic zinc finger motifs. The two zinc fingers contain eight conserved residues, mostly cysteines and histidines, which coordinately bond to two zinc atoms. LIM domains function as adaptors or scaffolds to support the assembly of multimeric protein complexes.

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gi 1789691067   5 CARCGKVVYPTEKVNCLDKYWHKGCFHCEVCKMALNMNNYKGYEKKPYCNAHY 57
Cdd:cd09840     1 CSRCGDSVYAAEKIMGAGKPWHKNCFRCAKCGKSLESTTLTEKEGEIYCKGCY 53

Second Src Homology 3 domain of Nck adaptor proteins; Nck adaptor proteins regulate actin cytoskeleton dynamics by linking proline-rich effector molecules to protein tyrosine kinases and phosphorylated signaling intermediates. They contain three SH3 domains and a C-terminal SH2 domain. They function downstream of the PDGFbeta receptor and are involved in Rho GTPase signaling and actin dynamics. Vertebrates contain two Nck adaptor proteins: Nck1 (also called Nckalpha) and Nck2 (also called Nckbeta or Growth factor receptor-bound protein 4, Grb4), which show partly overlapping functions but also bind distinct targets. Their SH3 domains are involved in recruiting downstream effector molecules, such as the N-WASP/Arp2/3 complex, which when activated induces actin polymerization that results in the production of pedestals, or protrusions of the plasma membrane. The second SH3 domain of Nck appears to prefer ligands containing the APxxPxR motif. SH3 domains are protein interaction domains that usually bind to proline-rich ligands with moderate affinity and selectivity, preferentially a PxxP motif. 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 1789691067 245 TYRAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQrtGRTGMLPANYIE 298
Cdd:cd11766     1 PAVVKFNYEAQREDELSLRKGDRVLVLEKSSDGWWRGECN--GQVGWFPSNYVT 52

The second LIM domain of Cysteine Rich Protein 3 (CRP3/MLP); The second LIM domain of Cysteine Rich Protein 3 (CRP3/MLP): Cysteine-rich proteins (CRPs) are characterized by the presence of two LIM domains linked to short glycine-rich repeats (GRRs). The CRP family members include CRP1, CRP2, CRP3/MLP and TLPCRP1, CRP2 and CRP3 share a conserved nuclear targeting signal (K/R-K/R-Y-G-P-K), which supports the fact that these proteins function not only in the cytoplasm but also in the nucleus. CRPs control regulatory pathways during cellular differentiation, and involve in complex transcription circuits, and the organization as well as the arrangement of the myofibrillar/cytoskeletal network.CRP3 also called Muscle LIM Protein (MLP), which is a striated muscle-specific factor that enhances myogenic differentiation. The second LIM domain of CRP3/MLP interacts with cytoskeletal protein beta-spectrin. CRP3/MLP also interacts with the basic helix-loop-helix myogenic transcription factors MyoD, myogenin, and MRF4 thereby increasing their affinity for specific DNA regulatory elements. LIM domains are 50-60 amino acids in size and share two characteristic zinc finger motifs. The two zinc fingers contain eight conserved residues, mostly cysteines and histidines, which coordinately bond to two zinc atoms. LIM domains function as adaptors or scaffolds to support the assembly of multimeric protein complexes.

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gi 1789691067   5 CARCGKVVYPTEKVNCLDKYWHKGCFHCEVCKMALNMNNYKGYEKKPYCNAHY 57
Cdd:cd09482     1 CPRCGKSVYAAEKVMGGGKPWHKTCFRCAICGKSLESTTVTDKDGELYCKVCY 53

Src homology 3 domains of the p47phox subunit of NADPH oxidase and similar domains; This family is composed of the tandem SH3 domains of p47phox subunit of NADPH oxidase and Nox Organizing protein 1 (NoxO1), the four SH3 domains of Tks4 (Tyr kinase substrate with four SH3 domains), the five SH3 domains of Tks5, the SH3 domain of obscurin, Myosin-I, and similar domains. Most members of this group also contain Phox homology (PX) domains, except for obscurin and Myosin-I. p47phox and NoxO1 are regulators of the phagocytic NADPH oxidase complex (also called Nox2 or gp91phox) and nonphagocytic NADPH oxidase Nox1, respectively. They play roles in the activation of their respective NADPH oxidase, which catalyzes the transfer of electrons from NADPH to molecular oxygen to form superoxide. Tks proteins are Src substrates and scaffolding proteins that play important roles in the formation of podosomes and invadopodia, the dynamic actin-rich structures that are related to cell migration and cancer cell invasion. Obscurin is a giant muscle protein that plays important roles in the organization and assembly of the myofibril and the sarcoplasmic reticulum. Type I myosins (Myosin-I) are actin-dependent motors in endocytic actin structures and actin patches. They play roles in membrane traffic in endocytic and secretory pathways, cell motility, and mechanosensing. Myosin-I contains an N-terminal actin-activated ATPase, a phospholipid-binding TH1 (tail homology 1) domain, and a C-terminal extension which includes an F-actin-binding TH2 domain, an SH3 domain, and an acidic peptide that participates in activating the Arp2/3complex. The SH3 domain of myosin-I is required for myosin-I-induced actin polymerization. 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 1789691067 245 TYRAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYgtVQRTGRTGMLPANYIE 298
Cdd:cd11856     1 SYVAIADYEAQGDDEISLQEGEVVEVLEKNDSGWWY--VRKGDKEGWVPASYLE 52

Src Homology 3 domain of eumetazoan Peroxisomal biogenesis factor 13; PEX13 is a peroxin and is required for protein import into the peroxisomal matrix and membrane. It is an integral membrane protein that is essential for the localization of PEX14 and the import of proteins containing the peroxisome matrix targeting signals, PTS1 and PTS2. Mutations of the PEX13 gene in humans lead to a wide range of peroxisome biogenesis disorders (PBDs), the most severe of which is known as Zellweger syndrome (ZS), a severe multisystem disorder characterized by hypotonia, psychomotor retardation, and neuronal migration defects. PEX13 contains two transmembrane regions 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.

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gi 1789691067 247 RAMYDYSAQDEDEVSFRDGDyIVNV-----QPIDDGWMYGTVQRTgRTGMLPANYIE 298
Cdd:cd11864     3 RAEYDFVAESEDELSFRAGD-KLRLapkelQPRVRGWLLATVDGQ-KIGLVPANYVK 57

Src homology 3 domain of Phospholipase C (PLC) gamma; PLC catalyzes the hydrolysis of phosphatidylinositol (4,5)-bisphosphate [PtdIns(4,5)P2] to produce Ins(1,4,5)P3 and diacylglycerol (DAG) in response to various receptors. Ins(1,4,5)P3 initiates the calcium signaling cascade while DAG functions as an activator of PKC. PLCgamma catalyzes this reaction in tyrosine kinase-dependent signaling pathways. It is activated and recruited to its substrate at the membrane. Vertebrates contain two forms of PLCgamma, PLCgamma1, which is widely expressed, and PLCgamma2, which is primarily found in haematopoietic cells. PLCgamma contains a Pleckstrin homology (PH) domain followed by an elongation factor (EF) domain, two catalytic regions of PLC domains that flank two tandem SH2 domains, followed by a SH3 domain and C2 domain. The SH3 domain of PLCgamma1 directly interacts with dynamin-1 and can serve as a guanine nucleotide exchange factor (GEF). It also interacts with Cbl, inhibiting its phosphorylation and activity. 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 1789691067 245 TYRAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWM---YGtvqrTGRTGMLPANYIE 298
Cdd:cd11825     1 TVKALYDYRAQRPDELSFCKHAIITNVEKEDGGWWrgdYG----GKKQKWFPANYVE 53

Third Src Homology 3 domain of SH3 domain containing ring finger 1, an E3 ubiquitin-protein ligase; SH3RF1 is also called POSH (Plenty of SH3s) or SH3MD2 (SH3 multiple domains protein 2). It is a scaffold protein that acts as an E3 ubiquitin-protein ligase. It plays a role in calcium homeostasis through the control of the ubiquitin domain protein Herp. It may also have a role in regulating death receptor mediated and JNK mediated apoptosis. SH3RF1 also enhances the ubiquitination of ROMK1 potassium channel resulting in its increased endocytosis. It contains an N-terminal RING finger domain and four SH3 domains. This model represents the third SH3 domain, located in the middle, of SH3RF1. 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 1789691067 246 YRAMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQRTGRTGMLPANYI 297
Cdd:cd11926     2 YVAIYPYTPRKEDELELRKGEMFLVFERCQDGWFKGTSMHTSKIGVFPGNYV 53

The second Lim domain of pollen specific protein SF3; The second Lim domain of pollen specific protein SF3: SF3 is a Lim protein that is found exclusively in mature plant pollen grains. It contains two LIM domains. The exact function of SF3 is unknown. It may be a transcription factor required for the expression of late pollen genes. It is possible that SF3 protein is involved in controlling pollen-specific processes such as male gamete maturation, pollen tube formation, or even fertilization. As in other LIM domains, this domain family is 50-60 amino acids in size and shares two characteristic zinc finger motifs. The two zinc fingers contain eight conserved residues, mostly cysteines and histidines, which coordinately bond to two zinc atoms. LIM domains function as adaptors or scaffolds to support the assembly of multimeric protein.

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gi 1789691067   5 CARCGKVVYPTEKVNCLDKYWHKGCFHCEVCKMALNMNNYKGYEKKPYCNAHY 57
Cdd:cd09441     1 CVACGKTVYPIEKVTVEGTSYHKSCFKCSHGGCTISPSNYAAHEGRLYCKHHH 53

First Src Homology 3 domain (SH3A) 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 first SH3 domain (SH3A) of CIN85; SH3A binds to internal proline-rich motifs within the proline-rich region. This intramolecular interaction serves as a regulatory mechanism to keep CIN85 in a closed conformation, preventing the recruitment of other proteins. SH3A has also been shown to bind ubiquitin and to an atypical PXXXPR motif at the C-terminus of Cbl and the cytoplasmic end of the cell adhesion protein CD2. 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 1789691067 250 YDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQrtGRTGMLPANYI 297
Cdd:cd12052     6 FDYKAQHEDELTITVGDIITKIKKDDGGWWEGEIK--GRRGLFPDNFV 51

Fourth Src homology 3 domain of ADAM-binding protein Eve-1; Eve-1, also called SH3 domain-containing protein 19 (SH3D19) or EEN-binding protein (EBP), exists in multiple alternatively spliced isoforms. The longest isoform contains five SH3 domain in the C-terminal region and seven proline-rich motifs in the N-terminal region. It is abundantly expressed in skeletal muscle and heart, and may be involved in regulating the activity of ADAMs (A disintegrin and metalloproteases). Eve-1 interacts with EEN, an endophilin involved in endocytosis and may be the target of the MLL-EEN fusion protein that is implicated in leukemogenesis. 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 1789691067 248 AMYDYSAQDEDEVSFRDGDYIVNVQPIDDGWMYGTVQrtGRTGMLPANY 296
Cdd:cd11817     4 ALYDFTGETEEDLSFQRGDRILVTEHLDAEWSRGRLN--GREGIFPRAF 50