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 1752397205   5 CARCLRTVYPVEEMKCLDKSWHKGCFTCESCGMTLNMKNYKGYDKLPYCHAHY 57
Cdd:cd09447     1 CARCGKTVYPTEKLNCLDKIWHKGCFKCEVCGMTLNMKNYKGYNKKPYCNAHY 53

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

                           10        20
                   ....*....|....*....|....*....
gi 1752397205   62 FTTVADTPENRRLAKNTKTQSQVEYQKQF 90
Cdd:smart00227   1 YTSVPDTPEILLAKKNQKLISDVKYKEDY 29

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 1752397205   5 CARCLRTVYPVEEMKCLDKSWHKGCFTCESCGMTLNMKNYKGYDKLPYCHAHY 57
Cdd:cd09447     1 CARCGKTVYPTEKLNCLDKIWHKGCFKCEVCGMTLNMKNYKGYNKKPYCNAHY 53

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 1752397205  177 QPNKYRAIYDYLAADQDEVSFKEGDLVVNWQHIDEGWMTGTIERtGQKGMLPSNYVQ 233
Cdd:smart00326   1 EGPQVRALYDYTAQDPDELSFKKGDIITVLEKSDDGWWKGRLGR-GKEGLFPSNYVE 56

Zinc-binding domain present in Lin-11, Isl-1, Mec-3; Zinc-binding domain family. Some LIM domains bind protein partners via tyrosine-containing motifs. LIM domains are found in many key regulators of developmental pathways.

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|...
gi 1752397205    5 CARCLRTVYPVEE-MKCLDKSWHKGCFTCESCGMTLNMKNYKGYDKLPYCHAH 56
Cdd:smart00132   2 CAGCGKPIYGTERvLRALGKVWHPECFKCATCGKPLSGDTFFEKDGKLYCKDC 54

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

                           10        20
                   ....*....|....*....|....*....
gi 1752397205   62 FTTVADTPENRRLAKNTKTQSQVEYQKQF 90
Cdd:smart00227   1 YTSVPDTPEILLAKKNQKLISDVKYKEDY 29

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 1752397205   5 CARCLRTVYPVEEMKCLDKSWHKGCFTCESCGMTLNMKNYKGYDKLPYCHAHY 57
Cdd:cd09447     1 CARCGKTVYPTEKLNCLDKIWHKGCFKCEVCGMTLNMKNYKGYNKKPYCNAHY 53

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 1752397205 180 KYRAIYDYLAADQDEVSFKEGDLVVNWQHIDEGWMTGTIERTGQKGMLPSNYVQPV 235
Cdd:cd11934     4 RYRAVYDYNAADEDEVSFQDGDTIVNVQQIDDGWMYGTVERTGDTGMLPANYVEAI 59

The LIM domain of LIM and SH3 Protein (LASP)-like proteins; The LIM domain of LIM and SH3 Protein (LASP) like proteins: This family contains two types of LIM containing proteins; LASP and N-RAP. 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. N-RAP is a muscle-specific protein concentrated at myotendinous junctions in skeletal muscle and intercalated disks in cardiac muscle. LIM domain is found at the N-terminus of N-RAP and the C-terminal of N-RAP contains a region with multiple of nebulin repeats. N-RAP functions as a scaffolding protein that organizes alpha-actinin and actin into symmetrical I-Z-I structures in developing myofibrils. Nebulin repeat is known as actin binding domain. The N-RAP is hypothesized to form antiparallel dimerization via its LIM domain. 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 1752397205   5 CARCLRTVYPVEEMKCLDKSWHKGCFTCESCGMTLNMKNYKGYDKLPYCHAHY 57
Cdd:cd09359     1 CARCGKIVYPTEKVNCLDKTWHKACFHCEVCKMTLNMNNYKGYQKKPYCNAHY 53

The LIM domain of N-RAP; The LIM domain of N-RAP: N-RAP is a muscle-specific protein concentrated at myotendinous junctions in skeletal muscle and intercalated disks in cardiac muscle. LIM domain is found at the N-terminus of N-RAP and the C-terminal of N-RAP contains a region with multiple of nebulin repeats. N-RAP functions as a scaffolding protein that organizes alpha-actinin and actin into symmetrical I-Z-I structures in developing myofibrils. Nebulin repeat is known as actin binding domain. The N-RAP is hypothesized to form antiparallel dimerization via its LIM domain. 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 1752397205   5 CARCLRTVYPVEEMKCLDKSWHKGCFTCESCGMTLNMKNYKGYDKLPYCHAH 56
Cdd:cd09446     1 CARCGYGVYPAEKINCIDQTWHKACFHCEVCKMMLTVNNFVSHQKKPYCQAH 52

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 1752397205  177 QPNKYRAIYDYLAADQDEVSFKEGDLVVNWQHIDEGWMTGTIERtGQKGMLPSNYVQ 233
Cdd:smart00326   1 EGPQVRALYDYTAQDPDELSFKKGDIITVLEKSDDGWWKGRLGR-GKEGLFPSNYVE 56

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 1752397205 180 KYRAIYDYLAADQDEVSFKEGDLVVNWQHIDEGWMTGTIERtGQKGMLPSNY 231
Cdd:cd00174     1 YARALYDYEAQDDDELSFKKGDIITVLEKDDDGWWEGELNG-GREGLFPANY 51

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 1752397205 181 YRAIYDYLAADQDEVSFKEGDLVVNWQHIDEGWMTGTIERTGQKGMLPSNYVQP 234
Cdd:cd11780     2 YRALYSYTPQNEDELELREGDIVYVMEKCDDGWFVGTSERTGLFGTFPGNYVAR 55

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        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|
gi 1752397205 176 GQPnkYRAIYDYLAADQDEVSFKEGDLVVNWQHIDEGWMTGTIERTGQKGMLPSNYVQPV 235
Cdd:cd11918     1 RTP--YKAVYQYRPQNEDELELREGDRVDVMQQCDDGWFVGVSRRTQKFGTFPGNYVAPV 58

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 1752397205 181 YRAIYDYLAADQDEVSFKEGDLVVNWQHIDEGWMTGTIERTGQKGMLPSNYVQPV 235
Cdd:cd11916     4 YQALYSYAPQNDDELELRDGDIVDVMEKCDDGWFVGTSRRTKQFGTFPGNYVKLL 58

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

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 1752397205   5 CARCLRTVYPVEEMKCLDKSWHKGCFTCESCGMTLNMKNYKGYDKLPYCHAHY 57
Cdd:pfam00412   1 CAGCNRPIYDRELVRALGKVWHPECFRCAVCGKPLTTGDFYEKDGKLYCKHDY 53

LIM is a small protein-protein interaction domain, containing two zinc fingers; LIM domains are identified in a diverse group of proteins with wide variety of biological functions, including gene expression regulation, cell fate determination, cytoskeleton organization, tumor formation and development. LIM domains function as adaptors or scaffolds to support the assembly of multimeric protein complexes. They perform their functions through interactions with other protein partners. LIM domains are 50-60 amino acids in size and share two characteristic highly conserved zinc finger motifs. The two zinc fingers contain eight conserved residues, mostly cysteines and histidines, which coordinately bond to two zinc atoms. The consensus sequence of LIM domain has been defined as C-x(2)-C-x(16,23)-H-x(2)-[CH]-x(2)-C-x(2)-C-x(16,21)-C-x(2,3)-[CHD] (where X denotes any amino acid).

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 1752397205   5 CARCLRTVYPVEEMKCLDKSWHKGCFTCESCGMTLNMKNYKGYDKLPYCHAHY 57
Cdd:cd08368     1 CAGCGKPIEGRELLRALGKKWHPECFKCAECGKPLGGDSFYEKDGKPYCEKCY 53

Variant SH3 domain;

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 1752397205 183 AIYDYLAADQDEVSFKEGDLVVNWQHIDEGWMTGtiERTGQKGMLPSNYVQ 233
Cdd:pfam14604   1 ALYPYEPKDDDELSLQRGDVITVIEESEDGWWEG--INTGRTGLVPANYVE 49

The LIM domains of Cysteine Rich Protein (CRP) family; The LIM domains of Cysteine Rich Protein (CRP) family: Cysteine-rich proteins (CRPs) are characterized by the presence of two LIM domains linked to a short glycine-rich repeats (GRRs). The known CRP family members include CRP1, CRP2, and CRP3/MLP. CRP1, 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 control, and the organization as well as the arrangement of the myofibrillar/cytoskeletal network. CRP1, CRP2, and CRP3/MLP are involved in promoting protein assembly along the actin-based cytoskeleton. All 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 1752397205   5 CARCLRTVYPVEEMKCLDKSWHKGCFTCESCGMTLNMKNYKGYDKLPYCHAHY 57
Cdd:cd09326     1 CPRCGKSVYAAEEVIAAGKSWHKSCFTCAVCNKRLDSTTLAEHDGEIYCKSCY 53

The first Lim domain of pollen specific protein SF3; The first 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.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 1752397205   5 CARCLRTVYPVEEMKCLDKSWHKGCFTCESCGMTLNMKNYKGYDKLPYCHAHY 57
Cdd:cd09440     5 CKACDKTVYLVDQLSADGVVYHKSCFRCSHCKGTLKLSNYSSMEGVLYCKPHF 57

Src Homology 3 domain of GTPase Regulator Associated with Focal adhesion kinase and similar proteins; This subfamily is composed of Rho GTPase activating proteins (GAPs) with similarity to GRAF. Members contain an N-terminal BAR domain, followed by a Pleckstrin homology (PH) domain, a Rho GAP domain, and a C-terminal SH3 domain. Although vertebrates harbor four Rho GAPs in the GRAF subfamily including GRAF, GRAF2, GRAF3, and Oligophrenin-1 (OPHN1), only three are included in this model. OPHN1 contains the BAR, PH and GAP domains, but not the C-terminal SH3 domain. GRAF and GRAF2 show GAP activity towards RhoA and Cdc42. GRAF influences Rho-mediated cytoskeletal rearrangements and binds focal adhesion kinase. GRAF2 regulates caspase-activated p21-activated protein kinase-2. The SH3 domain of GRAF and GRAF2 binds PKNbeta, a target of the small GTPase Rho. SH3 domains bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs; they play a role in the regulation of enzymes by intramolecular interactions, changing the subcellular localization of signal pathway components and mediate multiprotein complex assemblies.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....
gi 1752397205 182 RAIYDYLAADQDEVSFKEGDLVVNWQHIDE-GWMTGTIErtGQKGMLPSNYVQP 234
Cdd:cd11882     3 RALYACKAEDESELSFEPGQIITNVQPSDEpGWLEGTLN--GRTGLIPENYVEF 54

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 1752397205 180 KYRAIYDYLAADQDEVSFKEGDLVVNWQHIDEGWMtgTIERTGQKGMLPSNYVQ 233
Cdd:cd11824     1 KYSVLYDYTAQEDDELSISKGDVVAVIEKGEDGWW--TVERNGQKGLVPGTYLE 52

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.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|..
gi 1752397205 182 RAIYDYLAADQDEVSFKEGDLVVNWQHIDEGWMTGTIErtGQKGMLPSNYVQ 233
Cdd:cd11827     3 KALYAYDAQDTDELSFNEGDIIEILKEDPSGWWTGRLR--GKEGLFPGNYVE 52

Src Homology 3 domain of Sorting Nexin 9 and similar proteins; Sorting nexins (SNXs) are Phox homology (PX) domain containing proteins that are involved in regulating membrane traffic and protein sorting in the endosomal system. SNXs differ from each other in their lipid-binding specificity, subcellular localization and specific function in the endocytic pathway. This subfamily consists of SH3 domain containing SNXs including SNX9, SNX18, SNX33, and similar proteins. SNX9 is localized to plasma membrane endocytic sites and acts primarily in clathrin-mediated endocytosis, while SNX18 is localized to peripheral endosomal structures, and acts in a trafficking pathway that is clathrin-independent but relies on AP-1 and PACS1. 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 1752397205 180 KYRAIYDYLAADQDEVSFKEGD-LVVNWQHIDEGWMTGTIERtGQKGMLPSNYVQP 234
Cdd:cd11763     1 KVRALYDFDSQPSGELSLRAGEvLTITRQDVGDGWLEGRNSR-GEVGLFPSSYVEI 55

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 1752397205 180 KYRAIYDYLAADQDEVSFKEGDLVVNWQHIDEGWMTGTIErtGQKGMLPSNYVQP 234
Cdd:cd11877     1 LVRAKFNFEGTNEDELSFDKGDIITVTQVVEGGWWEGTLN--GKTGWFPSNYVKE 53

Src homology 3 domain of Hematopoietic lineage cell-specific protein 1; HS1, also called HCLS1 (hematopoietic cell-specific Lyn substrate 1), is a cortactin homolog expressed specifically in hematopoietic cells. It is an actin regulatory protein that binds the Arp2/3 complex and stabilizes branched actin filaments. It is required for cell spreading and signaling in lymphocytes. It regulates cytoskeletal remodeling that controls lymphocyte trafficking, and it also affects tissue invasion and infiltration of leukemic B cells. Like cortactin, HS1 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 binds the Arp2/3 complex and F-actin, while the C-terminal region acts as an adaptor or scaffold that can connect varied 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 1752397205 183 AIYDYLAADQDEVSFKEGDLVVNWQHIDEGWMTGTIErtGQKGMLPSNYVQ 233
Cdd:cd12073     5 ALYDYQGEGDDEISFDPQETITDIEMVDEGWWKGTCH--GHRGLFPANYVE 53

First Src Homology 3 domain of SH3 domain containing ring finger proteins; This model represents the first SH3 domain of SH3RF1 (or POSH), SH3RF2 (or POSHER), SH3RF3 (POSH2), and similar domains. Members of this family are scaffold proteins that function as E3 ubiquitin-protein ligases. They all contain an N-terminal RING finger domain and multiple SH3 domains; SH3RF1 and SH3RF3 have four SH3 domains while SH3RF2 has three. 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. SH3RF2 acts as an anti-apoptotic regulator of the JNK pathway by binding to and promoting the degradation 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.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|..
gi 1752397205 182 RAIYDYLAADQDEVSFKEGDLVVNWQHIDEGWMTGtiERTGQKGMLPSNYVQ 233
Cdd:cd11786     3 KALYNYEGKEPGDLSFKKGDIILLRKRIDENWYHG--ECNGKQGFFPASYVQ 52

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 1752397205 180 KYRAIYDYLAADQDEVSFKEGDLVVNWQHIDEGWMTGTIErtGQKGMLPSNYV 232
Cdd:cd11873     1 EVIVEFDYDAEEPDELTLKVGDIITNVKKMEEGWWEGTLN--GKRGMFPDNFV 51

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 1752397205   5 CARCLRTVYPVEEMKCLDKSWHKGCFTCESCGMTLNMKNYKGY--DKLPYCHAH 56
Cdd:cd09443     1 CPRCGKTAYPAESVDKDGTFYHKGCFKCRECGTRLSLKTFTFVqgDGEVYCARH 54

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 1752397205 180 KYRAIYDYLAADQDEVSFKEGDLV--VNWQHIDEGWMTGtiERTGQKGMLPSNYVQP 234
Cdd:cd11875     1 KARVLFDYEAENEDELTLREGDIVtiLSKDCEDKGWWKG--ELNGKRGVFPDNFVEP 55

Src Homology 3 domain of Ras GTPase-Activating Protein 1; RasGAP, also called Ras p21 protein activator, RASA1, or p120RasGAP, is part of the GAP1 family of GTPase-activating proteins. It is a 120kD cytosolic protein containing an SH3 domain flanked by two SH2 domains at the N-terminal end, a pleckstrin homology (PH) domain, a calcium dependent phospholipid binding domain (CaLB/C2), and a C-terminal catalytic GAP domain. It stimulates the GTPase activity of normal RAS p21. It acts as a positive effector of Ras in tumor cells. It also functions as a regulator downstream of tyrosine receptors such as those of PDGF, EGF, ephrin, and insulin, among others. The SH3 domain of RasGAP is unable to bind proline-rich sequences but have been shown to interact with protein partners such as the G3BP protein, Aurora kinases, and the Calpain small subunit 1. The RasGAP SH3 domain is necessary for the downstream signaling of Ras and it also influences Rho-mediated cytoskeletal reorganization. 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.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*....
gi 1752397205 178 PNKYRAIYDYLAA-DQDEVSFKEGDLVVNWQHIDEGWMTGTIERTGQKGMLPSNYVQPV 235
Cdd:cd11788     1 RRRVRAILPYNKVpDTDELSFQKGDIFVVHNELEDGWLWVTSLRTGESGLVFRDLVEEL 59

Fifth Src homology 3 domain (or SH3E) of Intersectin; Intersectins (ITSNs) are adaptor proteins that function in exo- and endocytosis, actin cytoskeletal reorganization, and signal transduction. They are essential for initiating clathrin-coated pit formation. They bind to many proteins through their multidomain structure and facilitate the assembly of multimeric complexes. Vertebrates contain two ITSN proteins, ITSN1 and ITSN2, which exist in alternatively spliced short and long isoforms. The short isoforms contain two Eps15 homology domains (EH1 and EH2), a coiled-coil region and five SH3 domains (SH3A-E), while the long isoforms, in addition, contain RhoGEF (also called Dbl-homologous or DH), Pleckstrin homology (PH) and C2 domains. ITSN1 and ITSN2 are both widely expressed, with variations depending on tissue type and stage of development. 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.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*
gi 1752397205 180 KYRAIYDYLAADQDEVSFKEGDLVVNWQHIDEGWMTGtiERTGQKGMLPSNYVQP 234
Cdd:cd11840     1 QVIALFPYTAQNEDELSFQKGDIINVLSKDDPDWWRG--ELNGQTGLFPSNYVEP 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.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|...
gi 1752397205   5 CARCLRTVYPVEEMKCLDKSWHKGCFTCESCGMTLNMKNYKGYDKLPYCHAHY 57
Cdd:cd09441     1 CVACGKTVYPIEKVTVEGTSYHKSCFKCSHGGCTISPSNYAAHEGRLYCKHHH 53

Third Src Homology 3 domain of the fungal endocytic adaptor protein Sla1p; Sla1p facilitates endocytosis by playing a role as an adaptor protein in coupling components of the actin cytoskeleton to the endocytic machinery. It interacts with Abp1p, Las17p and Pan1p, which are activator proteins of actin-related protein 2/3 (Arp2/3). Sla1p contains multiple domains including three SH3 domains, a SAM (sterile alpha motif) domain, and a Sla1 homology domain 1 (SHD1), which binds to the NPFXD motif that is found in many integral membrane proteins such as the Golgi-localized Arf-binding protein Lsb5p and the P4-ATPases, Drs2p and Dnf1p. The third SH3 domain of Sla1p can bind ubiquitin while retaining the ability to bind proline-rich ligands; monoubiquitination of target proteins signals internalization and sorting through the endocytic pathway. 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 1752397205 182 RAIYDYLAADQDEVSFKEGDLV--VNWQHIDEGWMTGTIErTGQKGMLPSNYVQP 234
Cdd:cd11775     4 KVLYDFDAQSDDELTVKEGDVVyiLDDKKSKDWWMVENVS-TGKEGVVPASYIEI 57

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 1752397205 183 AIYDYLAADQDEVSFKEGDLVVNWQHI-----DEGWMTGTIERtgQKGMLPSNYVQP 234
Cdd:cd11876     4 ALFDYDARGEDELTLRRGQPVEVLSKDaavsgDEGWWTGKIGD--KVGIFPSNYVAP 58

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 1752397205 180 KYRAIYDYLAADQDEVSFKEGDLVVNWQHIDE-GWMTGTIErTGQKGMLPSNYVQ 233
Cdd:cd11997     3 RVRALYDYTGQEADELSFKAGEELLKIGEEDEqGWCKGRLL-SGRIGLYPANYVE 56

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.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....
gi 1752397205 181 YRAIYDYLAADQDEVSFKEGDLVVNWQHIDEGWMTGTIERTGQKGMLPSNYVQP 234
Cdd:cd11926     2 YVAIYPYTPRKEDELELRKGEMFLVFERCQDGWFKGTSMHTSKIGVFPGNYVAP 55

Src Homology 3 domain of Mixed Lineage Kinases 1, 2, and 3; MLKs 1, 2, and 3 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. Little is known about the specific function of MLK1, also called MAP3K9. It is capable of activating the c-Jun N-terminal kinase pathway. Mice lacking both MLK1 and MLK2 are viable, fertile, and have normal life spans. MLK2, also called MAP3K10, is abundant in brain, skeletal muscle, and testis. It functions upstream of the MAPK, c-Jun N-terminal kinase. It binds hippocalcin, a calcium-sensor protein that protects neurons against calcium-induced cell death. Both MLK2 and hippocalcin may be associated with the pathogenesis of Parkinson's disease. MLK3, also called MAP3K11, is highly expressed in breast cancer cells and its signaling through c-Jun N-terminal kinase has been implicated in the migration, invasion, and malignancy of cancer cells. It also functions as a negative regulator of Inhibitor of Nuclear Factor-KappaB Kinase (IKK) and thus, impacts inflammation and immunity. MLKs 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        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|
gi 1752397205 183 AIYDYLAADQDEVSFKEGDLV--------VNWqhiDEGWMTGTIErtGQKGMLPSNYVQP 234
Cdd:cd12059     4 AVFDYEASAEDELTLRRGDRVevlskdsaVSG---DEGWWTGKIN--DRVGIFPSNYVTS 58

The Lim domain of Epithelial Protein Lost in Neoplasm (Eplin) like proteins; The Lim domain of Epithelial Protein Lost in Neoplasm (Eplin) like proteins: This family contains Epithelial Protein Lost in Neoplasm in Neoplasm (Eplin), xin actin-binding repeat-containing protein 2 (XIRP2) and a group of protein with unknown function. The members of this family all contain a single LIM domain. Epithelial Protein Lost in Neoplasm is a cytoskeleton-associated tumor suppressor whose expression inversely correlates with cell growth, motility, invasion and cancer mortality. Eplin interacts and stabilizes F-actin filaments and stress fibers, which correlates with its ability to suppress anchorage independent growth. In epithelial cells, Eplin is required for formation of the F-actin adhesion belt by binding to the E-cadherin-catenin complex through alpha-catenin. Eplin is expressed in two isoforms, a longer Eplin-beta and a shorter Eplin-alpha. Eplin-alpha mRNA is detected in various tissues and cell lines, but is absent or down regulated in cancer cells. Xirp2 contains a LIM domain and Xin re peats for binding to and stabilising F-actin. Xirp2 is expressed in muscles and is significantly induced in the heart in response to systemic administration of angiotensin II. Xirp2 is an important effector of the Ang II signaling pathway in the heart. The expression of Xirp2 is activated by myocyte enhancer factor (MEF)2A, whose transcriptional activity is stimulated by angiotersin II. Thus, Xirp2 plays important pathological roles in the angiotensin II induced hypertension. 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 1752397205   5 CARCLRTVYPVEEMKCLDKSWHKGCFTCESCGMTLNMKNYKGYDKLPYCHAHY 57
Cdd:cd09442     1 CTVCQKRVYPMERLIADKQNFHKSCFRCEHCNSKLSLGNYASLHGRIYCKPHF 53

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.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|.
gi 1752397205 183 AIYDYLAADQDEVSFKEGDLVVNWQHIDEGWMTGTIerTGQKGMLPSNYVQ 233
Cdd:cd11996     5 AMYDYTANNEDELSFSKGQLINVLNKDDPDWWQGEI--NGVTGLFPSNYVK 53

Src Homology 3 domain of Sorting nexin 18; SNX18 is localized to peripheral endosomal structures, and acts in a trafficking pathway that is clathrin-independent but relies on AP-1 and PACS1. It binds FIP5 and is required for apical lumen formation. It may also play a role in axonal elongation. SNXs are Phox homology (PX) domain containing proteins that are involved in regulating membrane traffic and protein sorting in the endosomal system. SNX18 also contains BAR and SH3 domains. 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 1752397205 182 RAIYDYLAADQDEVSFKEGDLVVNWQHID-EGWMTGTIERtGQKGMLPSNYVQ 233
Cdd:cd11897     3 RALYDFRSENPGEISLREHEVLSLCSEQDiEGWLEGVNSR-GDRGLFPASYVE 54

Third Src Homology 3 domain of SH3 domain containing ring finger 3, an E3 ubiquitin-protein ligase; SH3RF3 is also called POSH2 (Plenty of SH3s 2) or SH3MD4 (SH3 multiple domains protein 4). It is a scaffold protein with E3 ubiquitin-protein ligase activity. It was identified in the screen for interacting partners of p21-activated kinase 2 (PAK2). It may play a role in regulating JNK mediated apoptosis in certain conditions. It also interacts with GTP-loaded Rac1. SH3RF3 is highly homologous to SH3RF1; it also contains an N-terminal RING finger domain and four SH3 domains. This model represents the third SH3 domain, located in the middle, of SH3RF3. 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 1752397205 179 NKYRAIYDYLAADQDEVSFKEGDLVVNWQHIDEGWMTGTIERTGQKGMLPSNYVQPV 235
Cdd:cd11925     1 NIYLALYAYKPQKNDELELRKGEMYRVIEKCQDGWFKGTSLRTGVSGVFPGNYVTPV 57

Src homology 3 domains of Rab3-interacting molecules (RIMs) binding proteins; RIMs binding proteins (RBPs, RIM-BPs) associate with calcium channels present in photoreceptors, neurons, and hair cells; they interact simultaneously with specific calcium channel subunits, and active zone proteins, RIM1 and RIM2. RIMs are part of the matrix at the presynaptic active zone and are associated with synaptic vesicles through their interaction with the small GTPase Rab3. RIM-BPs play a role in regulating synaptic transmission by serving as adaptors and linking calcium channels with the synaptic vesicle release machinery. RIM-BPs contain three SH3 domains and two to three fibronectin III repeats. Invertebrates contain one, while vertebrates contain at least two RIM-BPs, RIM-BP1 and RIM-BP2. RIM-BP1 is also called peripheral-type benzodiazapine receptor associated protein 1 (PRAX-1). Mammals contain a third protein, RIM-BP3. RIM-BP1 and RIM-BP2 are predominantly expressed in the brain where they display overlapping but distinct expression patterns, while RIM-BP3 is almost exclusively expressed in the testis and is essential in spermiogenesis. The SH3 domains of RIM-BPs bind to the PxxP motifs of RIM1, RIM2, and L-type (alpha1D) and N-type (alpha1B) calcium channel subunits. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity. 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        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 1752397205 180 KYRAIYDYLAADQ-------DEVSFKEGDLVVNWQHIDE-GWMTGTIERtGQKGMLPSNYVQP 234
Cdd:cd11851     1 LMVALYDYNPETMspnddpeEELSFHAGDVVRVYGPMDEdGFYYGELEG-GRKGLVPSNFVQE 62

Variant SH3 domain; SH3 (Src homology 3) domains are often indicative of a protein involved in signal transduction related to cytoskeletal organization. First described in the Src cytoplasmic tyrosine kinase. The structure is a partly opened beta barrel.

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                  ....*....|....*....|....*....|....*....|....*....|....*.
gi 1752397205 180 KYRAIYDYLAADQDEVSFKEGDLVVNWQHIDEGWMTGtiERTGQKGMLPSNYVQPV 235
Cdd:pfam07653   1 YGRVIFDYVGTDKNGLTLKKGDVVKVLGKDNDGWWEG--ETGGRVGLVPSTAVEEI 54

Src homology 3 domain of Abl Interactor 2; Abi2 is highly expressed in the brain and eye. It regulates actin cytoskeletal reorganization at adherens junctions and dendritic spines, which is important in cell morphogenesis, migration, and cognitive function. Mice deficient with Abi2 show defects in orientation and migration of lens fibers, neuronal migration, dendritic spine morphology, as well as deficits in learning and memory. 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. 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.

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                  ....*....|....*....|....*....|....*....|....*....|....*.
gi 1752397205 180 KYRAIYDYLAADQDEVSFKEGDLVVNWQHIDEGWMTGTIerTGQKGMLPSNYVQPV 235
Cdd:cd11972     4 KVVAIYDYTKDKEDELSFQEGAIIYVIKKNDDGWYEGVM--NGVTGLFPGNYVESI 57

First Src Homology 3 domain (SH3A) of CD2-associated protein; CD2AP, also called CMS (Cas ligand with Multiple SH3 domains) or METS1 (Mesenchyme-to-Epithelium Transition protein with SH3 domains), is a cytosolic adaptor protein that plays a role in regulating the cytoskeleton. It is critical in cell-to-cell union necessary for kidney function. It also stabilizes the contact between a T cell and antigen-presenting cells. It is primarily expressed in podocytes at the cytoplasmic face of the slit diaphragm and serves as a linker anchoring podocin and nephrin to the actin cytoskeleton. CD2AP contains three SH3 domains, a proline-rich region, and a C-terminal coiled-coil domain. All of these domains enable CD2AP 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 CD2AP. SH3A binds to the PXXXPR motif present in c-Cbl and the cytoplasmic domain of cell adhesion protein CD2. Its interaction with CD2 anchors CD2 at sites of cell contact. 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 1752397205 185 YDYLAADQDEVSFKEGDLVVNWQHIDE-GWMTGtiERTGQKGMLPSNYVQPV 235
Cdd:cd12053     6 YDYDAVHEDELTIRVGEIIRNVKKLEEeGWLEG--ELNGRRGMFPDNFVKEI 55

The second LIM domain of Lhx2 and Lhx9 family; The second LIM domain of Lhx2 and Lhx9 family: Lhx2 and Lhx9 are highly homologous LHX regulatory proteins. They belong to the LHX protein family, which features two tandem N-terminal LIM domains and a C-terminal DNA binding homeodomain. Members of LHX family are found in the nucleus and act as transcription factors or cofactors. LHX proteins are critical for the development of specialized cells in multiple tissue types, including the nervous system, skeletal muscle, the heart, the kidneys, and endocrine organs, such as the pituitary gland and the pancreas. Although Lhx2 and Lhx9 are highly homologous, they seems to play regulatory roles in different organs. In animals, Lhx2 plays important roles in eye, cerebral cortex, limb, the olfactory organs, and erythrocyte development. Lhx2 gene knockout mice exhibit impaired patterning of the cortical hem and the telencephalon of the developing brain, and a lack of development in olfactory structures. Lhx9 is expressed in several regions of the developing mouse brain, the spinal cord, the pancreas, in limb mesenchyme, and in the urogenital region. Lhx9 plays critical roles in gonad development. Homozygous mice lacking functional Lhx9 alleles exhibit numerous urogenital defects, such as gonadal agenesis, infertility, and undetectable levels of testosterone and estradiol coupled with high FSH levels. Lhx9 null mice are phenotypically female, even those that are genotypically male. 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.