Third Src homology 3 domain 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 568972667 1336 MVAAFDYNPRENSPNMDVEAELPFRAGDVITVFGNMDDDGFYYGELNGQRGLVPSNFLEG 1395
Cdd:cd12013     2 MVALFDYDPRESSPNVDAEVELSFRAGDIITVFGEMDEDGFYYGELNGQRGLVPSNFLEE 61

Chromosome segregation ATPase Smc [Cell cycle control, cell division, chromosome partitioning];

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568972667    2 REVAQRRQQLEVEHEQARLSLQEKQEEVRRLQQAQAEAKRE---HEGAVQLLESTLDSMQARVRELEGQCRSQTERFSLL 78
Cdd:COG1196   256 EELEAELAELEAELEELRLELEELELELEEAQAEEYELLAElarLEQDIARLEERRRELEERLEELEEELAELEEELEEL 335

                  ....*.
gi 568972667   79 AQELQA 84
Cdd:COG1196   336 EEELEE 341

large tegument protein UL36; Provisional

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568972667  900 LEKPGPSRTSQDPSQPELALLGPGCDSSQPQGPGLCPLSPELSGVREhleDVLGVVGGNGRRRGGGSPEKLPNRKRPQDP 979
Cdd:PHA03247 2644 PTVPPPERPRDDPAPGRVSRPRRARRLGRAAQASSPPQRPRRRAARP---TVGSLTSLADPPPPPPTPEPAPHALVSATP 2720

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568972667  980 REHCSRLLGNGGPQASARPVPPR--ERGSLPVIEGTRVG-QEPGGRGRPGLSRRCPRGPAPESS--LVSCLSPKCLEISI 1054
Cdd:PHA03247 2721 LPPGPAAARQASPALPAAPAPPAvpAGPATPGGPARPARpPTTAGPPAPAPPAAPAAGPPRRLTrpAVASLSESRESLPS 2800

                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568972667 1055 EYDSEDEQEAGSGGVS-INSSCYPTDGEAWGTAAVgrPRGPPKVNPGPNAYLRLPAW-EKGEPERRgrsaigrtkEPPSR 1132
Cdd:PHA03247 2801 PWDPADPPAAVLAPAAaLPPAASPAGPLPPPTSAQ--PTAPPPPPGPPPPSLPLGGSvAPGGDVRR---------RPPSR 2869

                         250       260       270       280       290       300       310       320
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568972667 1133 ATETGESrgqdnSGRRGPQRRGARVPRSGTTE-LAPPRSPQEAPPHQDLPVRvfvalfdydpvsmsPNPDAGEEELPFKE 1211
Cdd:PHA03247 2870 SPAAKPA-----APARPPVRRLARPAVSRSTEsFALPPDQPERPPQPQAPPP--------------PQPQPQPPPPPQPQ 2930

                         330       340       350       360       370       380       390       400
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568972667 1212 GQLlkvfgdkdadgfyrgESGGRTGYIPCNMVAEVAVDSPAGRQQLLQRGFLPPNVLTEASGNGPSVYSSAHTPGPPPKP 1291
Cdd:PHA03247 2931 PPP---------------PPPPRPQPPLAPTTDPAGAGEPSGAVPQPWLGALVPGRVAVPRFRVPQPAPSREAPASSTPP 2995

                  ...
gi 568972667 1292 RRS 1294
Cdd:PHA03247 2996 LTG 2998

Third Src homology 3 domain 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 568972667 1336 MVAAFDYNPRENSPNMDVEAELPFRAGDVITVFGNMDDDGFYYGELNGQRGLVPSNFLEG 1395
Cdd:cd12013     2 MVALFDYDPRESSPNVDAEVELSFRAGDIITVFGEMDEDGFYYGELNGQRGLVPSNFLEE 61

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        60
                    ....*....|....*....|....*....|....*....|....*....|....*....|
gi 568972667   1336 MVAAFDYNPREnspnmdvEAELPFRAGDVITVFgNMDDDGFYYGELN-GQRGLVPSNFLE 1394
Cdd:smart00326    5 VRALYDYTAQD-------PDELSFKKGDIITVL-EKSDDGWWKGRLGrGKEGLFPSNYVE 56

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.

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|
gi 568972667  1335 PMVAAFDYNPRENSPnmdveaeLPFRAGDVITVFGnMDDDGFYYGELNGQRGLVPSNFLE 1394
Cdd:pfam07653    1 YGRVIFDYVGTDKNG-------LTLKKGDVVKVLG-KDNDGWWEGETGGRVGLVPSTAVE 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        60
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 568972667   1181 PVRVFVALFDYDPVSmspnpdagEEELPFKEGQLLKVFGDKDaDGFYRGESG-GRTGYIPCNMVA 1244
Cdd:smart00326    1 EGPQVRALYDYTAQD--------PDELSFKKGDIITVLEKSD-DGWWKGRLGrGKEGLFPSNYVE 56

Chromosome segregation ATPase Smc [Cell cycle control, cell division, chromosome partitioning];

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568972667    2 REVAQRRQQLEVEHEQARLSLQEKQEEVRRLQQAQAEAKRE---HEGAVQLLESTLDSMQARVRELEGQCRSQTERFSLL 78
Cdd:COG1196   256 EELEAELAELEAELEELRLELEELELELEEAQAEEYELLAElarLEQDIARLEERRRELEERLEELEEELAELEEELEEL 335

                  ....*.
gi 568972667   79 AQELQA 84
Cdd:COG1196   336 EEELEE 341

Ezrin/radixin/moesin, alpha-helical domain; The ERM family consists of three closely-related proteins, ezrin, radixin and moesin. Ezrin was first identified as a constituent of microvilli, radixin as a barbed, end-capping actin-modulating protein from isolated junctional fractions, and moesin as a heparin binding protein. A tumour suppressor molecule responsible for neurofibromatosis type 2 (NF2) is highly similar to ERM proteins and has been designated merlin (moesin-ezrin-radixin-like protein). ERM molecules contain 3 domains, an N-terminal globular domain, an extended alpha-helical domain and a charged C-terminal domain (pfam00769). Ezrin, radixin and merlin also contain a polyproline linker region between the helical and C-terminal domains. The N-terminal domain is highly conserved and is also found in merlin, band 4.1 proteins and members of the band 4.1 superfamily, designated the FERM domain. ERM proteins crosslink actin filaments with plasma membranes. They co-localize with CD44 at actin filament plasma membrane interaction sites, associating with CD44 via their N-terminal domains and with actin filaments via their C-terminal domains. This is the alpha-helical domain, which is involved in intramolecular masking of protein-protein interaction sites, regulating the activity of this proteins.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568972667     2 REVAQRRQQLEVEHEQARLSLQEKQEEVRRL----QQAQAEAKR------EHEGAVQLLESTlDSMQARVRE-LEGQCRS 70
Cdd:pfam20492    9 QELEERLKQYEEETKKAQEELEESEETAEELeeerRQAEEEAERleqkrqEAEEEKERLEES-AEMEAEEKEqLEAELAE 87

                           90
                   ....*....|....
gi 568972667    71 QTERFSLLAQELQA 84
Cdd:pfam20492   88 AQEEIARLEEEVER 101

Fibronectin type 3 domain; One of three types of internal repeat within the plasma protein, fibronectin. The tenth fibronectin type III repeat contains a RGD cell recognition sequence in a flexible loop between 2 strands. Type III modules are present in both extracellular and intracellular proteins.

                            10        20        30        40        50        60        70
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 568972667    445 PSQLRIHRLTATSAEIAWVPGNSNLAHAIYLN----------GEECPPARPSTYWATFCNLRPGTLYQARVEA 507
Cdd:smart00060    4 PSNLRVTDVTSTSVTLSWEPPPDDGITGYIVGyrveyreegsEWKEVNVTPSSTSYTLTGLKPGTEYEFRVRA 76

chromosome segregation protein SMC, common bacterial type; SMC (structural maintenance of chromosomes) proteins bind DNA and act in organizing and segregating chromosomes for partition. SMC proteins are found in bacteria, archaea, and eukaryotes. This family represents the SMC protein of most bacteria. The smc gene is often associated with scpB (TIGR00281) and scpA genes, where scp stands for segregation and condensation protein. SMC was shown (in Caulobacter crescentus) to be induced early in S phase but present and bound to DNA throughout the cell cycle. [Cellular processes, Cell division, DNA metabolism, Chromosome-associated proteins]

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 568972667     2 REVAQRRQQLEV---EHEQARLSLQEKQEEVRRLQQAQAE--------AKREHEGAVQLLESTLDSMQARVRELEGQCRS 70
Cdd:TIGR02168  386 SKVAQLELQIASlnnEIERLEARLERLEDRRERLQQEIEEllkkleeaELKELQAELEELEEELEELQEELERLEEALEE 465

                           90
                   ....*....|....*.
gi 568972667    71 QTERFSLLAQELQAFR 86
Cdd:TIGR02168  466 LREELEEAEQALDAAE 481

Third Src homology 3 domain 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 568972667 1336 MVAAFDYNPRENSPNMDVEAELPFRAGDVITVFGNMDDDGFYYGELNGQRGLVPSNFLEG 1395
Cdd:cd12013     2 MVALFDYDPRESSPNVDAEVELSFRAGDIITVFGEMDEDGFYYGELNGQRGLVPSNFLEE 61

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 568972667 1336 MVAAFDYNPRENSPNMDVEAELPFRAGDVITVFGNMDDDGFYYGELNG-QRGLVPSNFLE 1394
Cdd:cd11851     2 MVALYDYNPETMSPNDDPEEELSFHAGDVVRVYGPMDEDGFYYGELEGgRKGLVPSNFVQ 61

First Src homology 3 domain 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
                  ....*....|....*....|....*....|....*....|....*....|....*....
gi 568972667 1337 VAAFDYNPRENSPNMDVEAELPFRAGDVITVFGNMDDDGFYYGEL-NGQRGLVPSNFLE 1394
Cdd:cd12014     3 VARYSYNPLRDSPNENPEAELPLNAGDYVYVYGDMDEDGFYEGELlDGRRGLVPSNFVE 61

Second Src homology 3 domain 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
                  ....*....|....*....|....*....|....*....|....*....|....*....
gi 568972667 1337 VAAFDYNPRENSPNMD-VEAELPFRAGDVITVFGNMDDDGFYYGELNGQRGLVPSNFLE 1394
Cdd:cd12012     3 VALFDYDPLTMSPNPDaAEEELPFKEGQLIKVYGDKDADGFYLGEINGRRGLVPCNMVS 61

Third Src homology 3 domain 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 568972667 1186 VALFDYDPVSMSPNPDAgEEELPFKEGQLLKVFGDKDADGFYRGESGGRTGYIPCNMVAE 1245
Cdd:cd12013     3 VALFDYDPRESSPNVDA-EVELSFRAGDIITVFGEMDEDGFYYGELNGQRGLVPSNFLEE 61

First Src homology 3 domain 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 568972667 1184 VFVALFDYDPVSMSPNpDAGEEELPFKEGQLLKVFGDKDADGFYRGES-GGRTGYIPCNMV 1243
Cdd:cd12014     1 VFVARYSYNPLRDSPN-ENPEAELPLNAGDYVYVYGDMDEDGFYEGELlDGRRGLVPSNFV 60

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.

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 568972667  1184 VFVALFDYDPvsmspnpdAGEEELPFKEGQLLKVFgDKDADGFYRGESGGRTGYIPCNMVAEV 1246
Cdd:pfam07653    1 YGRVIFDYVG--------TDKNGLTLKKGDVVKVL-GKDNDGWWEGETGGRVGLVPSTAVEEI 54

Variant SH3 domain;

                           10        20        30        40        50
                   ....*....|....*....|....*....|....*....|....*....|....*..
gi 568972667  1338 AAFDYNPREnspnmdvEAELPFRAGDVITVFGNmDDDGFYYGELNGQRGLVPSNFLE 1394
Cdd:pfam14604    1 ALYPYEPKD-------DDELSLQRGDVITVIEE-SEDGWWEGINTGRTGLVPANYVE 49

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

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 568972667 1184 VFVALFDYDPVsmspNPDageeELPFKEGQLLKVFgDKDADGFYRGESGGRTGYIPCNMVAE 1245
Cdd:cd11772     1 VFRALYDYEAQ----HPD----ELSFEEGDLLYIS-DKSDPNWWKATCGGKTGLIPSNYVEE 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        60
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 568972667   1181 PVRVFVALFDYDPVSmspnpdagEEELPFKEGQLLKVFGDKDaDGFYRGESG-GRTGYIPCNMVA 1244
Cdd:smart00326    1 EGPQVRALYDYTAQD--------PDELSFKKGDIITVLEKSD-DGWWKGRLGrGKEGLFPSNYVE 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 568972667 1184 VFVALFDYDPvsmspnpdAGEEELPFKEGQLLKVFgDKDADGFYRGES-GGRTGYIPCN 1241
Cdd:cd00174     1 YARALYDYEA--------QDDDELSFKKGDIITVL-EKDDDGWWEGELnGGREGLFPAN 50

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 568972667 1340 FDYNPrENspnmdvEAELPFRAGDVITVFG-NMDDDGFYYGELNGQRGLVPSNFLE 1394
Cdd:cd11875     6 FDYEA-EN------EDELTLREGDIVTILSkDCEDKGWWKGELNGKRGVFPDNFVE 54

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 568972667 1336 MVAAFDYNPRENSpnmdveaELPFRAGDVITVFGNMDDDGFYYGELNGQRGLVPSNF 1392
Cdd:cd11778     2 VEALYDYEAQGDD-------EISIRVGDRIAVIRGDDGSGWTYGEINGVKGLFPTSY 51

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

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gi 568972667 1337 VAAFDYNPRENSpnmdveaELPFRAGDVITVFgNMDDDGFYYGELNGQRGLVPSNFLE 1394
Cdd:cd11823     3 KALYSYTANRED-------ELSLQPGDIIEVH-EKQDDGWWLGELNGKKGIFPATYVE 52

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 568972667 1338 AAFDYNPRENSpnmdveaELPFRAGDVITVFGNMDDDgFYYGELNGQRGLVPSNFLE 1394
Cdd:cd11805     4 ALYDFNPQEPG-------ELEFRRGDIITVLDSSDPD-WWKGELRGRVGIFPANYVQ 52

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.

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gi 568972667 1354 EAELPFRAGDVITVFGNMDDDGFYYGELNGQRGLVPSNFLE 1394
Cdd:cd11882    13 ESELSFEPGQIITNVQPSDEPGWLEGTLNGRTGLIPENYVE 53

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.

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gi 568972667 1337 VAAFDYNPREnspnmdvEAELPFRAGDVITVFgNMDDDGFYYGELNGQRGLVPSNFLE 1394
Cdd:cd11840     3 IALFPYTAQN-------EDELSFQKGDIINVL-SKDDPDWWRGELNGQTGLFPSNYVE 52

Src homology 3 domain of Src kinase-like Protein Tyrosine Kinases; Src subfamily members include Src, Lck, Hck, Blk, Lyn, Fgr, Fyn, Yrk, Yes, and Brk. Src (or c-Src) proteins are cytoplasmic (or non-receptor) PTKs which are anchored to the plasma membrane. They contain an N-terminal SH4 domain with a myristoylation site, followed by SH3 and SH2 domains, a tyr kinase domain, and a regulatory C-terminal region containing a conserved tyr. They are activated by autophosphorylation at the tyr kinase domain, but are negatively regulated by phosphorylation at the C-terminal tyr by Csk (C-terminal Src Kinase). However, Brk lacks the N-terminal myristoylation sites. Src proteins are involved in signaling pathways that regulate cytokine and growth factor responses, cytoskeleton dynamics, cell proliferation, survival, and differentiation. They were identified as the first proto-oncogene products, and they regulate cell adhesion, invasion, and motility in cancer cells, and tumor vasculature, contributing to cancer progression and metastasis. Src kinases are overexpressed in a variety of human cancers, making them attractive targets for therapy. They are also implicated in acute inflammatory responses and osteoclast function. Src, Fyn, Yes, and Yrk are widely expressed, while Blk, Lck, Hck, Fgr, Lyn, and Brk show a limited expression pattern. This subfamily also includes Drosophila Src42A, Src oncogene at 42A (also known as Dsrc41) which accumulates at sites of cell-cell or cell-matrix adhesion, and participates in Drosphila development and wound healing. It has been shown to promote tube elongation in the tracheal system, is essential for proper cell-cell matching during dorsal closure, and regulates cell-cell contacts in developing Drosophila eyes. The SH3 domain of Src kinases contributes to substrate recruitment by binding adaptor proteins/substrates, and regulation of kinase activity through an intramolecular interaction. 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 568972667 1184 VFVALFDYDPVsmspnpdaGEEELPFKEGQLLKVFGDKDADGFY-RGESGGRTGYIPCN 1241
Cdd:cd11845     1 IYVALYDYEAR--------TDDDLSFKKGDRLQILDDSDGDWWLaRHLSTGKEGYIPSN 51

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 568972667  1186 VALFDYDPVSmspnpdagEEELPFKEGQLLKVFGDKDaDGFYRGES-GGRTGYIPC 1240
Cdd:pfam00018    1 VALYDYTAQE--------PDELSFKKGDIIIVLEKSE-DGWWKGRNkGGKEGLIPS 47

N-terminal Src homology 3 domain of GRB2-related adaptor protein 2; GRAP2 is also called GADS (GRB2-related adapter downstream of Shc), GrpL, GRB2L, Mona, or GRID (Grb2-related protein with insert domain). It is expressed specifically in the hematopoietic system. It 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. It also have roles in antigen-receptor and tyrosine kinase mediated signaling. GRAP2 is unique from other GRB2-like adaptor proteins in that it can be regulated by caspase cleavage. It contains an N-terminal SH3 domain, a central SH2 domain, and a C-terminal SH3 domain. The N-terminal SH3 domain of the related protein GRB2 binds to Sos and Sos-derived proline-rich peptides. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

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gi 568972667 1354 EAELPFRAGDVITVFGNmdDDGFYYGELNGQRGLVPSNFLE 1394
Cdd:cd11947    13 EDELSFKKGDVLKILSS--DDIWFKAELNGEEGYVPKNFVD 51

Src homology 3 domain of Slit-Robo GTPase Activating Proteins; Slit-Robo GTPase Activating Proteins (srGAPs) are Rho GAPs that interact with Robo1, the transmembrane receptor of Slit proteins. Slit proteins are secreted proteins that control axon guidance and the migration of neurons and leukocytes. Vertebrates contain three isoforms of srGAPs (srGAP1-3), all of which are expressed during embryonic and early development in the nervous system but with different localization and timing. A fourth member has also been reported (srGAP4, also called ARHGAP4). srGAPs contain an N-terminal F-BAR domain, a Rho GAP 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 568972667 1337 VAAFDYNPREnspnmdvEAELPFRAGDVITVFGNMDDDgFYYGELNGQRGLVPSNFL 1393
Cdd:cd11809     3 TAQFDYTGRS-------ERELSFKKGDSLTLYRQVSDD-WWRGQLNGQDGLVPHKYI 51

N-terminal Src homology 3 domain of GRB2-related adaptor protein; GRAP is a GRB-2 like adaptor protein that is highly expressed in lymphoid tissues. It acts as a negative regulator of T cell receptor (TCR)-induced lymphocyte proliferation by downregulating the signaling to the Ras/ERK pathway. It has been identified as a regulator of TGFbeta signaling in diabetic kidney tubules and may have a role in the pathogenesis of the disease. GRAP contains an N-terminal SH3 domain, a central SH2 domain, and a C-terminal SH3 domain. The N-terminal SH3 domain of the related protein GRB2 binds to Sos and Sos-derived proline-rich peptides. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

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gi 568972667 1337 VAAFDYNPRENSpnmdveaELPFRAGDVITVFGNMDDDGFYYGELNGQRGLVPSNFLE 1394
Cdd:cd11948     3 VALYSFQATESD-------ELPFQKGDILKILNMEDDQNWYKAELQGREGYIPKNYIK 53

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.

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gi 568972667 1337 VAAFDYNPREnspnmdvEAELPFRAGDVITVFgNMDDDGFYYGELNGQRGLVPSNFLE 1394
Cdd:cd11824     3 SVLYDYTAQE-------DDELSISKGDVVAVI-EKGEDGWWTVERNGQKGLVPGTYLE 52

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

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gi 568972667 1337 VAAFDYNPREnspnmdvEAELPFRAGDVITVFGNMDDDGFYYGELNGQRGLVPSNFL 1393
Cdd:cd11804     3 VAKHDFKATA-------EDELSFKKGSILKVLNMEDDPNWYKAELDGKEGLIPKNYI 52

N-terminal Src homology 3 domain of GRB2-related adaptor protein; GRAP is a GRB-2 like adaptor protein that is highly expressed in lymphoid tissues. It acts as a negative regulator of T cell receptor (TCR)-induced lymphocyte proliferation by downregulating the signaling to the Ras/ERK pathway. It has been identified as a regulator of TGFbeta signaling in diabetic kidney tubules and may have a role in the pathogenesis of the disease. GRAP contains an N-terminal SH3 domain, a central SH2 domain, and a C-terminal SH3 domain. The N-terminal SH3 domain of the related protein GRB2 binds to Sos and Sos-derived proline-rich peptides. SH3 domains are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs. They play versatile and diverse roles in the cell including the regulation of enzymes, changing the subcellular localization of signaling pathway components, and mediating the formation of multiprotein complex assemblies.

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gi 568972667 1186 VALFDYdpvsmspnPDAGEEELPFKEGQLLKVFGDKDADGFYRGESGGRTGYIPCNMV 1243
Cdd:cd11948     3 VALYSF--------QATESDELPFQKGDILKILNMEDDQNWYKAELQGREGYIPKNYI 52

Src homology 3 domain of Endophilin-A; Endophilins play roles in synaptic vesicle formation, virus budding, mitochondrial morphology maintenance, receptor-mediated endocytosis inhibition, and endosomal sorting. They are classified into two types, A and B. Vertebrates contain three endophilin-A isoforms (A1, A2, and A3). Endophilin-A proteins are enriched in the brain and play multiple roles in receptor-mediated endocytosis. They tubulate membranes and regulate calcium influx into neurons to trigger the activation of the endocytic machinery. They are also involved in the sorting of plasma membrane proteins, actin filament assembly, and the uncoating of clathrin-coated vesicles for fusion with endosomes. Endophilins contain an N-terminal N-BAR domain (BAR domain with an additional N-terminal amphipathic helix), followed by a variable region containing proline clusters, 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 568972667 1187 ALFDYDPVSmspnpdagEEELPFKEGQLLKVFGDKDaDGFYRGESGGRTGYIPCNMV 1243
Cdd:cd11803     5 ALYDFEPEN--------EGELGFKEGDIITLTNQID-ENWYEGMVNGQSGFFPVNYV 52

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

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gi 568972667 1187 ALFDYDPVSmspnpdagEEELPFKEGQLLKVFGDKDA---DGFYRGESGGRTGYIPCNMVAE 1245
Cdd:cd11762     4 ALYDYEAQS--------DEELSFPEGAIIRILRKDDNgvdDGWWEGEFNGRVGVFPSLVVEE 57

N-terminal Src Homology 3 domain of Ct10 Regulator of Kinase adaptor proteins; CRK adaptor proteins consists of SH2 and SH3 domains, which bind tyrosine-phosphorylated peptides and proline-rich motifs, respectively. They function downstream of protein tyrosine kinases in many signaling pathways started by various extracellular signals, including growth and differentiation factors. Cellular CRK (c-CRK) contains a single SH2 domain, followed by N-terminal and C-terminal SH3 domains. It is involved in the regulation of many cellular processes including cell growth, motility, adhesion, and apoptosis. CRK has been implicated in the malignancy of various human cancers. The N-terminal SH3 domain of CRK binds a number of target proteins including DOCK180, C3G, SOS, and cABL. The CRK family includes two alternatively spliced protein forms, CRKI and CRKII, that are expressed by the CRK gene, and the CRK-like (CRKL) protein, which is expressed by a distinct gene (CRKL). 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.