PDZ domain of regulator of G-protein signaling 3 (RGS3), and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of RGS3, and related domains. RGS3 down-regulates GPCR signal transduction by increasing the GTPase activity of G-protein alpha subunits, thereby driving G-proteins into their inactive GDP-bound form. It downregulates G-protein-mediated release of inositol phosphates and activation of MAP kinases. In Eph/ephrin signaling, RGS3 binds via its PDZ domain to the cytoplasmic C terminus of Eph receptor tyrosine kinase EphB. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This RGS3-like family domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 755506600 194 LQITIRRGKDGFGFTICCDSPVRVQAVDSGGPAERAGLQQLDTVLQLNERPVEHWKCVELAHEIRSCPSEIILLVWR 270
Cdd:cd06711    1 LQITIQRGKDGFGFTICDDSPVRVQAVDPGGPAEQAGLQQGDTVLQINGQPVERSKCVELAHAIRNCPSEIILLVWR 77

PDZ domain of regulator of G-protein signaling 3 (RGS3), and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of RGS3, and related domains. RGS3 down-regulates GPCR signal transduction by increasing the GTPase activity of G-protein alpha subunits, thereby driving G-proteins into their inactive GDP-bound form. It downregulates G-protein-mediated release of inositol phosphates and activation of MAP kinases. In Eph/ephrin signaling, RGS3 binds via its PDZ domain to the cytoplasmic C terminus of Eph receptor tyrosine kinase EphB. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This RGS3-like family domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 755506600 194 LQITIRRGKDGFGFTICCDSPVRVQAVDSGGPAERAGLQQLDTVLQLNERPVEHWKCVELAHEIRSCPSEIILLVWR 270
Cdd:cd06711    1 LQITIQRGKDGFGFTICDDSPVRVQAVDPGGPAEQAGLQQGDTVLQINGQPVERSKCVELAHAIRNCPSEIILLVWR 77

Protein kinase C conserved region 2 (CalB); Ca2+-binding motif present in phospholipases, protein kinases C, and synaptotagmins (among others). Some do not appear to contain Ca2+-binding sites. Particular C2s appear to bind phospholipids, inositol polyphosphates, and intracellular proteins. Unusual occurrence in perforin. Synaptotagmin and PLC C2s are permuted in sequence with respect to N- and C-terminal beta strands. SMART detects C2 domains using one or both of two profiles.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755506600    47 VLLLHIIEGKGLMSREP-GICDPYVKVSLIPEDSQlpCQTTQIIPDCRDPAFHEHFFFPVPEEGDQkRLLVTVWNRASET 125
Cdd:smart00239   1 TLTVKIISARNLPPKDKgGKSDPYVKVSLDGDPKE--KKKTKVVKNTLNPVWNETFEFEVPPPELA-ELEIEVYDKDRFG 77

                           90
                   ....*....|....*...
gi 755506600   126 RqHTLIGCMSFGVRSLLT 143
Cdd:smart00239  78 R-DDFIGQVTIPLSDLLL 94

PDZ domain; PDZ domains are found in diverse signaling proteins.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755506600  195 QITIRRGKDG-FGFTI-----CCDSPVRVQAVDSGGPAERAGLQQLDTVLQLNERPVEHWKCVELAHEIRSCPSEIILLV 268
Cdd:pfam00595   1 QVTLEKDGRGgLGFSLkggsdQGDPGIFVSEVLPGGAAEAGGLKVGDRILSINGQDVENMTHEEAVLALKGSGGKVTLTI 80

                  .
gi 755506600  269 W 269
Cdd:pfam00595  81 L 81

periplasmic serine protease, Do/DeqQ family; This family consists of a set proteins various designated DegP, heat shock protein HtrA, and protease DO. The ortholog in Pseudomonas aeruginosa is designated MucD and is found in an operon that controls mucoid phenotype. This family also includes the DegQ (HhoA) paralog in E. coli which can rescue a DegP mutant, but not the smaller DegS paralog, which cannot. Members of this family are located in the periplasm and have separable functions as both protease and chaperone. Members have a trypsin domain and two copies of a PDZ domain. This protein protects bacteria from thermal and other stresses and may be important for the survival of bacterial pathogens.// The chaperone function is dominant at low temperatures, whereas the proteolytic activity is turned on at elevated temperatures. [Protein fate, Protein folding and stabilization, Protein fate, Degradation of proteins, peptides, and glycopeptides]

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*.
gi 755506600  215 VRVQAVDSGGPAERAGLQQLDTVLQLNERPVEHWKCVELAHEIRSCPSEIILLVWR 270
Cdd:TIGR02037 364 VVVTKVVSGSPAARAGLQPGDVILSVNQQPVSSVAELRKVLARAKKGGRVALLILR 419

PDZ domain of regulator of G-protein signaling 3 (RGS3), and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of RGS3, and related domains. RGS3 down-regulates GPCR signal transduction by increasing the GTPase activity of G-protein alpha subunits, thereby driving G-proteins into their inactive GDP-bound form. It downregulates G-protein-mediated release of inositol phosphates and activation of MAP kinases. In Eph/ephrin signaling, RGS3 binds via its PDZ domain to the cytoplasmic C terminus of Eph receptor tyrosine kinase EphB. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This RGS3-like family domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 755506600 194 LQITIRRGKDGFGFTICCDSPVRVQAVDSGGPAERAGLQQLDTVLQLNERPVEHWKCVELAHEIRSCPSEIILLVWR 270
Cdd:cd06711    1 LQITIQRGKDGFGFTICDDSPVRVQAVDPGGPAEQAGLQQGDTVLQINGQPVERSKCVELAHAIRNCPSEIILLVWR 77

C2 domain; The C2 domain was first identified in PKC. C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755506600  48 LLLHIIEGKGLMSRE-PGICDPYVKVSLIPEdsqlPCQTTQIIPDCRDPAFHEHFFFPVPEEGDQkRLLVTVWNRaSETR 126
Cdd:cd00030    1 LRVTVIEARNLPAKDlNGKSDPYVKVSLGGK----QKFKTKVVKNTLNPVWNETFEFPVLDPESD-TLTVEVWDK-DRFS 74

                         90       100
                 ....*....|....*....|....*...
gi 755506600 127 QHTLIGCMSFGVRSLLTPDKEISGWYYL 154
Cdd:cd00030   75 KDDFLGEVEIPLSELLDSGKEGELWLPL 102

Protein kinase C conserved region 2 (CalB); Ca2+-binding motif present in phospholipases, protein kinases C, and synaptotagmins (among others). Some do not appear to contain Ca2+-binding sites. Particular C2s appear to bind phospholipids, inositol polyphosphates, and intracellular proteins. Unusual occurrence in perforin. Synaptotagmin and PLC C2s are permuted in sequence with respect to N- and C-terminal beta strands. SMART detects C2 domains using one or both of two profiles.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755506600    47 VLLLHIIEGKGLMSREP-GICDPYVKVSLIPEDSQlpCQTTQIIPDCRDPAFHEHFFFPVPEEGDQkRLLVTVWNRASET 125
Cdd:smart00239   1 TLTVKIISARNLPPKDKgGKSDPYVKVSLDGDPKE--KKKTKVVKNTLNPVWNETFEFEVPPPELA-ELEIEVYDKDRFG 77

                           90
                   ....*....|....*...
gi 755506600   126 RqHTLIGCMSFGVRSLLT 143
Cdd:smart00239  78 R-DDFIGQVTIPLSDLLL 94

PDZ domain 2 of delphilin (L-delphilin isoform), and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 2 of delphilin (also known as glutamate receptor, ionotropic, delta 2-interacting protein 1, L-delphilin). Delphilin, a postsynaptic protein which it is selectively expressed at cerebellar Purkinje cells, links the glutamate receptor delta 2 subunit (GluRdelta2) with the actin cytoskeleton and various signaling molecules. Two alternatively spliced isoforms of delphilin have been characterized: L-delphilin has two PDZ domains, PDZ1 and PDZ2, and S-delphilin has a single PDZ domain (PDZ2). These two isoforms are differently palmitoylated and may be involved in controlling GluRdelta2 signaling in Purkinje cells. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This delphilin-like family PDZ2 domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755506600 196 ITIRRGKDGFGFTICCDSPVRVQAVDSGGPAERAGLQQLDTVLQLNE---RPVEHWKCVELAHEIRSCPS 262
Cdd:cd06744    2 VRVYRGNGSFGFTLRGHAPVYIESVDPGSAAERAGLKPGDRILFLNGldvRNCSHDKVVSLLQGSGSMPT 71

PDZ domain of ARHGEF11, ARHGEF12, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of ARHGEF11, ARHGEF12, and related domains. This subfamily includes the GEFs (guanine exchange factors) ARHGEF11 (Rho guanine nucleotide exchange factor 11, known as PDZ-RhoGEF) and ARHGEF12 (Rho guanine nucleotide exchange factor 12, also known as leukemia-associated RhoGEF). GEFs activate Rho GTPases by promoting GTP binding. ARHGEF11/12 are regulators of G protein signaling (RGS) domain-containing GEFs; the RGS domain mediates their binding to and activation of Galpha (and Gq also in the case of ARHGEF12), in response to G-protein coupled receptor activation. ARHGEF11 and 12 are involved in serum-signaling, and regulate Yes-Associated Protein (YAP1)-dependent transcription. The ARHGEF12 PDZ domain binds plexin-B1 and the receptor tyrosine kinase insulin-like growth factor receptor (IGF-R1) beta-subunit. ARHGEF12 also interacts with glutamate receptor delta-1(GluD1), a postsynaptic organizer of inhibitory synapses in cortical pyramidal neurons. The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This ARHGEF11-12-like family domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 755506600 196 ITIRRGKDGFGFTICCDSPVRVQAVDSGGPAERAGLQQLDTVLQLNERPVEHWKCVELAHEIRS 259
Cdd:cd23069    4 VVIQRDENGYGLTVSGDNPVFVQSVKEGGAAYRAGVQEGDRIIKVNGTLVTHSNHLEVVKLIKS 67

PDZ domains of the Na+/H+ exchange regulatory cofactor (NHERF) family (NHERF1-4), and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of the Na+/H+ exchange regulatory cofactor (NHERF) family of multi-PDZ-domain-containing scaffolding proteins (NHERF1-4), and related domains. The NHERF family includes NHERF1 (also known as EBP50), NHERF2 (also known as E3KARP; TKA-1; SIP-1), NHERF3 (also known as CAP70; CLAMP; Napi-Cap-1; PDZD1) and NHERF4 (also known as IKEPP; PDZK2; Napi-Cap-2). NHERF1 and NHERF2 have tandem PDZ domains (PDZ1-2); NHERF3 and NHERF4 have four PDZ domains (PDZ1-4). NHERFs are involved in the regulation of multiple receptors or transporters, such as type II sodium-phosphate cotransporter (Npt2a), purinergic P2Y1 receptor P2Y1R, the beta2-adrenergic receptor (beta2-AR), parathyroid hormone receptor type 1 (PTHR), the lysophosphatidic acid receptors (LPARs), sodium-hydrogen exchanger 3 (NHE3), and cystic fibrosis transmembrane conductance regulator (CFTR). NHERF-PDZ1 domain interaction partners include Npt2a, purinergic P2Y1 receptor, beta2-AR, CFTR, PTHR, NH3, G-protein-coupled receptor kinase 6 (GRK6A), platelet-derived growth factor receptor (PDGFR), B1 subunit of the H+ATPase, cholesterol, receptor for activated C-kinase RACK1, aquaporin 9, among others. The NHERF PDZ2 domain interacts with fewer proteins: NHERF1 PDZ2 binds Npt2a, PTHR, beta-catenin, aquaporin 9, and RACK1; NHERF2 PDZ2 binds LPA2, P2Y1R, and NHE3, cGMP-dependent protein kinase type II (cGKII). NHERF4 PDZ1 and PDZ4 bind the epithelial Ca(2+) channels TRPV5 and TRPV6. NHERF2/NHERF3 heterodimerization is mediated by PDZ domains of NHERF2 and the C-terminal PDZ domain recognition motif of NHERF3. NHERF4 regulates several transporters mediating influx of xenobiotics and nutrients in the small intestine. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This NHERF-like family domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 755506600 197 TIRRGKDGFGFTICCDSPVR---VQAVDSGGPAERAGLQQLDTVLQLNERPVE---HWKCVELaheIRSCPSEIILLV 268
Cdd:cd06768    4 HLVKGPEGYGFNLHAEKGRPghfIREVDPGSPAERAGLKDGDRLVEVNGENVEgesHEQVVEK---IKASGNQVTLLV 78

C2 domain second repeat present in class II phosphatidylinositol 3-kinases (PI3Ks); There are 3 classes of PI3Ks based on structure, regulation, and specificity. All classes contain a N-terminal C2 domain, a PIK domain, and a kinase catalytic domain. Unlike class I and class III, class II PI3Ks have additionally a PX domain and a C-terminal C2 domain containing a nuclear localization signal both of which bind phospholipids though in a slightly different fashion. PI3Ks (AKA phosphatidylinositol (PtdIns) 3-kinases) regulate cell processes such as cell growth, differentiation, proliferation, and motility. PI3Ks work on phosphorylation of phosphatidylinositol, phosphatidylinositide (4)P (PtdIns (4)P),2 or PtdIns(4,5)P2. Specifically they phosphorylate the D3 hydroxyl group of phosphoinositol lipids on the inositol ring. C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. This cd contains the second C2 repeat, C2B, and has a type-I topology.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755506600  35 GQLKLSIDAQD---RVLLLHIiegKGLMSREPGICDPYVKVSLIPEDSQLPCQTTQIIPDCRDPAFHEHF---FFPVpEE 108
Cdd:cd08381    2 GQVKLSISYKNgtlFVMVMHA---KNLPLLDGSDPDPYVKTYLLPDPQKTTKRKTKVVRKTRNPTFNEMLvydGLPV-ED 77

                         90       100       110       120
                 ....*....|....*....|....*....|....*....|....*.
gi 755506600 109 GDQKRLLVTVWNRASeTRQHTLIGCMSFGVRSLLtPDKEISGWYYL 154
Cdd:cd08381   78 LQQRVLQVSVWSHDS-LVENEFLGGVCIPLKKLD-LSQETEKWYPL 121

C2 domain second repeat present in Rabphilin and Double C2 domain; Rabphilin is found neurons and in neuroendrocrine cells, while Doc2 is found not only in the brain but in tissues, including mast cells, chromaffin cells, and osteoblasts. Rabphilin and Doc2s share highly homologous tandem C2 domains, although their N-terminal structures are completely different: rabphilin contains an N-terminal Rab-binding domain (RBD),7 whereas Doc2 contains an N-terminal Munc13-1-interacting domain (MID). C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. This cd contains the second C2 repeat, C2B, and has a type-I topology.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755506600  36 QLKLSIDAQDRVLLLHIIEGKGLMSRE-PGICDPYVKVSLIPEDSQLPCQTTQIIPDCRDPAFHEHFFFPVPE-EGDQKR 113
Cdd:cd08384    3 LVSLMYNTQRRGLIVGIIRCVNLAAMDaNGYSDPFVKLYLKPDAGKKSKHKTQVKKKTLNPEFNEEFFYDIKHsDLAKKT 82

                         90       100       110       120       130
                 ....*....|....*....|....*....|....*....|....*....|..
gi 755506600 114 LLVTVWNRaSETRQHTLIGCMSFGVRS-----------LLTPDKEISGWYYL 154
Cdd:cd08384   83 LEITVWDK-DIGKSNDYIGGLQLGINAkgerlrhwldcLKNPDKKIEAWHTL 133

C2A domain first repeat present in Synaptotagmins 15 and 17; Synaptotagmin is a membrane-trafficking protein characterized by a N-terminal transmembrane region, a linker, and 2 C-terminal C2 domains. It is thought to be involved in the trafficking and exocytosis of secretory vesicles in non-neuronal tissues and is Ca2+ independent. Human synaptotagmin 15 has 2 alternatively spliced forms that encode proteins with different C-termini. The larger, SYT15a, contains a N-terminal TM region, a putative fatty-acylation site, and 2 tandem C terminal C2 domains. The smaller, SYT15b, lacks the C-terminal portion of the second C2 domain. Unlike most other synaptotagmins it is nearly absent in the brain and rather is found in the heart, lungs, skeletal muscle, and testis. Synaptotagmin 17 is located in the brain, kidney, and prostate and is thought to be a peripheral membrane protein. Previously all synaptotagmins were thought to be calcium sensors in the regulation of neurotransmitter release and hormone secretion, but it has been shown that not all of them bind calcium. Of the 17 identified synaptotagmins only 8 bind calcium (1-3, 5-7, 9, 10). The function of the two C2 domains that bind calcium are: regulating the fusion step of synaptic vesicle exocytosis (C2A) and binding to phosphatidyl-inositol-3,4,5-triphosphate (PIP3) in the absence of calcium ions and to phosphatidylinositol bisphosphate (PIP2) in their presence (C2B). C2B also regulates also the recycling step of synaptic vesicles. C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. This cd contains the first C2 repeat, C2A, and has a type-I topology.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755506600  35 GQLKLSI--DAQDRVLLLHIIEGKGLMSREPGI--CDPYVKVSLIPEDSQLpcQTTQIIPDCRDPAFHEHFFFPVPE-EG 109
Cdd:cd08390    1 GRLWFSVqyDLEEEQLTVSLIKARNLPPRTKDVahCDPFVKVCLLPDERRS--LQSKVKRKTQNPNFDETFVFQVSFkEL 78

                         90       100
                 ....*....|....*....|...
gi 755506600 110 DQKRLLVTVWNrASETRQHTLIG 132
Cdd:cd08390   79 QRRTLRLSVYD-VDRFSRHCIIG 100

C2 domain third repeat present in uncharacterized human KIAA1228-like proteins; KIAA proteins are uncharacterized human proteins. They were compiled by the Kazusa mammalian cDNA project which identified more than 2000 human genes. They are identified by 4 digit codes that precede the KIAA designation. Many KIAA genes are still functionally uncharacterized including KIAA1228. C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. This cd contains the third C2 repeat, C2C, and has a type-II topology.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755506600  35 GQLKLSI--DAQDRVLLLHIIEGKGLMSREP-GICDPYVKVSLIPEDSQLPCQTTQIIPDCRDPAFHEHFFFPVPEEGDQ 111
Cdd:cd04030    3 GRIQLTIrySSQRQKLIVTVHKCRNLPPCDSsDIPDPYVRLYLLPDKSKSTRRKTSVKKDNLNPVFDETFEFPVSLEELK 82

                         90
                 ....*....|...
gi 755506600 112 KRLL-VTVWNRAS 123
Cdd:cd04030   83 RRTLdVAVKNSKS 95

C2A domain first repeat present in Synaptotagmin 8; Synaptotagmin is a membrane-trafficking protein characterized by a N-terminal transmembrane region, a linker, and 2 C-terminal C2 domains. Previously all synaptotagmins were thought to be calcium sensors in the regulation of neurotransmitter release and hormone secretion, but it has been shown that not all of them bind calcium. Of the 17 identified synaptotagmins only 8 bind calcium (1-3, 5-7, 9, 10). The function of the two C2 domains that bind calcium are: regulating the fusion step of synaptic vesicle exocytosis (C2A) and binding to phosphatidyl-inositol-3,4,5-triphosphate (PIP3) in the absence of calcium ions and to phosphatidylinositol bisphosphate (PIP2) in their presence (C2B). C2B also regulates also the recycling step of synaptic vesicles. C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. This cd contains the first C2 repeat, C2A, and has a type-I topology.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755506600  33 DAGQLKLSI--DAQDRVLLLHIIEGKGLMSRE-PGICDPYVKVSLIPEDSQlPCQtTQIIPDCRDPAFHEHFFFPVPEEG 109
Cdd:cd08387    1 TRGELHFSLeyDKDMGILNVKLIQARNLQPRDfSGTADPYCKVRLLPDRSN-TKQ-SKIHKKTLNPEFDESFVFEVPPQE 78

                 ....*.
gi 755506600 110 DQKRLL 115
Cdd:cd08387   79 LPKRTL 84

PDZ domain of regulator of G-protein signaling 12 (RGS12), and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of RGS12, and related domains. RGS12 downregulates GPCR signal transduction by increasing the GTPase activity of G-protein alpha subunits, thereby driving G-proteins into their inactive GDP-bound form. The RGS12 PDZ domain can bind selectively to C-terminal (A/S)-T-X-(L/V) motifs as found within both the CXCR2 IL-8 receptor, and the alternative 3' exon form of RGS12. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This RGS12-like family domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*..
gi 755506600 196 ITIRRGKDGFGFTICCDSPVRVQAVDSGGPAERAGLQQLDTVLQLNE 242
Cdd:cd06710    3 VEIARGRAGYGFTISGQAPCVLSCVVRGSPADVAGLKAGDQILAVNG 49

C2 domain first repeat contained in Rab3-interacting molecule (RIM) proteins; RIMs are believed to organize specialized sites of the plasma membrane called active zones. They also play a role in controlling neurotransmitter release, plasticity processes, as well as memory and learning. RIM contains an N-terminal zinc finger domain, a PDZ domain, and two C-terminal C2 domains (C2A, C2B). C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. Members here have a type-I topology and do not bind Ca2+.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755506600  36 QLKLSIDAQDRVLLLHIIEGKGLMSREPG-ICDPYVKVSLIPEDSQLPCQTTQIIPDCRDPAFHEHF-FFPVPEEGDQKR 113
Cdd:cd04031    6 QIQLWYDKVTSQLIVTVLQARDLPPRDDGsLRNPYVKVYLLPDRSEKSKRRTKTVKKTLNPEWNQTFeYSNVRRETLKER 85

                 ....*...
gi 755506600 114 LL-VTVWN 120
Cdd:cd04031   86 TLeVTVWD 93

C2 domain first repeat present in Synaptotagmin-like proteins; All Slp members basically share an N-terminal Slp homology domain (SHD) and C-terminal tandem C2 domains (named the C2A domain and the C2B domain) with the SHD and C2 domains being separated by a linker sequence of various length. Slp1/JFC1 and Slp2/exophilin 4 promote granule docking to the plasma membrane. Additionally, their C2A domains are both Ca2+ independent, unlike the case in Slp3 and Slp4/granuphilin in which their C2A domains are Ca2+ dependent. It is thought that SHD (except for the Slp4-SHD) functions as a specific Rab27A/B-binding domain. In addition to Slps, rabphilin, Noc2, and Munc13-4 also function as Rab27-binding proteins. It has been demonstrated that Slp3 and Slp4/granuphilin promote dense-core vesicle exocytosis. Slp5 mRNA has been shown to be restricted to human placenta and liver suggesting a role in Rab27A-dependent membrane trafficking in specific tissues. C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. This cd contains the first C2 repeat, C2A, and has a type-I topology.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755506600  36 QLKLSIDAQDRVLLLHIIEGKGLMSREPG--ICDPYVKVSLIPEDSQLPCQTTQIIPDCRDPAFHEHFFFPVPE-EGDQK 112
Cdd:cd08521    4 EFSLSYNYKTGSLEVHIKECRNLAYADEKkkRSNPYVKVYLLPDKSKQSKRKTSVKKNTTNPVFNETLKYHISKsQLETR 83

                 ....*...
gi 755506600 113 RLLVTVWN 120
Cdd:cd08521   84 TLQLSVWH 91

C2 domain first repeat present in Synaptotagmin-like proteins; Synaptotagmin is a membrane-trafficking protein characterized by a N-terminal transmembrane region, a linker, and 2 C-terminal C2 domains. Previously all synaptotagmins were thought to be calcium sensors in the regulation of neurotransmitter release and hormone secretion, but it has been shown that not all of them bind calcium. Of the 17 identified synaptotagmins only 8 bind calcium (1-3, 5-7, 9, 10). The function of the two C2 domains that bind calcium are: regulating the fusion step of synaptic vesicle exocytosis (C2A) and binding to phosphatidyl-inositol-3,4,5-triphosphate (PIP3) in the absence of calcium ions and to phosphatidylinositol bisphosphate (PIP2) in their presence (C2B). C2B also regulates also the recycling step of synaptic vesicles. C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. This cd contains the first C2 repeat, C2A, and has a type-I topology.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 755506600  47 VLLLHIIEGKGLMSRE---PGICDPYVKVSLipEDSQlpcQTTQIIPDCRDPAFHEHFFFPVPEEGDQKrLLVTVWNR 121
Cdd:cd04024    2 VLRVHVVEAKDLAAKDrsgKGKSDPYAILSV--GAQR---FKTQTIPNTLNPKWNYWCEFPIFSAQNQL-LKLILWDK 73

PDZ domain of the microtubule-associated serine-threonine (MAST) protein kinase family; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of MAST family kinases, including MAST1-4. These MAST proteins contain a DUF1908 domain, a serine/threonine kinase domain, a AGC-kinase C-terminal domain, and a PDZ domain; MAST family member MASTL is a shorter protein lacking the PDZ domain. The PDZ domain gives the MAST family the capacity to scaffold its own kinase activity. These kinases are implicated in the inhibition of neurite outgrowth and regeneration in cultured cells. Their binding partners include microtubules, beta2-syntrophin, TNF receptor-associated factor 6 (TRAF6), cAMP-regulated phosphoprotein (ARPP-16), and PTEN. This family also includes Caenorhabditis elegans KIN-4 MAST kinase, a key longevity factor acting through binding PTEN phosphatase, and Drosophila Drop out which regulates dynein-dependent transport during embryonic development. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This MAST-like family domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755506600 196 ITIRRGKDGFGFTIccdSPVRV--------------QAVDSGGPAERAGLQQLDTVLQLNERPVEHWKCVELAHEIRSCP 261
Cdd:cd06705    5 IVIKKGPRGFGFTL---RAIRVyigdsdvytvhhlvTAVEEGSPAYEAGLRPGDLITHVNGEPVQGLLHTQVVQLILKGG 81

                         90
                 ....*....|..
gi 755506600 262 SEIILlvwRVVP 273
Cdd:cd06705   82 NKVSI---RATP 90

PDZ domain of Drosophila melanogaster PDZ and LIM domain protein Zasp52 (also known as Zasp), and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of Drosophila melanogaster Zasp52 and related domains. Drosophila melanogaster Zasp52 (also known as Z band alternatively spliced PDZ-motif protein or Zasp) colocalizes with integrins at myotendinous junctions and with alpha-actinin at Z-disks and is required for muscle attachment as well as Z-disk assembly and maintenance. The Zasp52 actin-binding site includes the extended PDZ domain and the ZM region. The Zasp52-PDZ domain is required for myofibril assembly. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This Zasp52-like family domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*....
gi 755506600 212 DSPVRVQAVDSGGPAERAGLQQLDTVLQLNERPVEHWKCVELAHEIRSCPSEIILLVWR 270
Cdd:cd23068   24 GQPLSIQKVNPGSPADKAGLRRGDVILRINGTDTSNLTHKQAQDLIKRAGNDLQLTVQR 82

C2 domain second repeat present in Synaptotagmin 7; Synaptotagmin is a membrane-trafficking protein characterized by a N-terminal transmembrane region, a linker, and 2 C-terminal C2 domains. Synaptotagmin 7, a member of class 2 synaptotagmins, is located in presynaptic plasma membranes in neurons, dense-core vesicles in endocrine cells, and lysosomes in fibroblasts. It has been shown to play a role in regulation of Ca2+-dependent lysosomal exocytosis in fibroblasts and may also function as a vesicular Ca2+-sensor. It is distinguished from the other synaptotagmins by having over 12 splice forms. Previously all synaptotagmins were thought to be calcium sensors in the regulation of neurotransmitter release and hormone secretion, but it has been shown that not all of them bind calcium. Of the 17 identified synaptotagmins only 8 bind calcium (1-3, 5-7, 9, 10). The function of the two C2 domains that bind calcium are: regulating the fusion step of synaptic vesicle exocytosis (C2A) and binding to phosphatidyl-inositol-3,4,5-triphosphate (PIP3) in the absence of calcium ions and to phosphatidylinositol bisphosphate (PIP2) in their presence (C2B). C2B also regulates also the recycling step of synaptic vesicles. C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. This cd contains the second C2 repeat, C2B, and has a type-I topology.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755506600  48 LLLHIIEGKGLMSRE-PGICDPYVKVSLIPEDSQLPCQTTQIIPDCRDPAFHEHFFFPVPEEgdQKR---LLVTVWNRAS 123
Cdd:cd08405   17 ITVNIIKARNLKAMDiNGTSDPYVKVWLMYKDKRVEKKKTVIKKRTLNPVFNESFIFNIPLE--RLRettLIITVMDKDR 94

                         90
                 ....*....|....*..
gi 755506600 124 ETRqHTLIGCMSFGVRS 140
Cdd:cd08405   95 LSR-NDLIGKIYLGWKS 110

C2 domain second repeat of Ras GTPase activating proteins (GAPs); RasGAPs suppress Ras function by enhancing the GTPase activity of Ras proteins resulting in the inactive GDP-bound form of Ras. In this way it can control cellular proliferation and differentiation. The proteins here all contain two tandem C2 domains, a Ras-GAP domain, and a pleckstrin homology (PH)-like domain. C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. Members here have a type-I topology.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755506600  48 LLLHIIEGKGLMSREPGICDPYVKVSLIPEDSQlPCQTTQIIPDCRDPAFHEHFFFPVP--------------EEGDQKR 113
Cdd:cd08675    1 LSVRVLECRDLALKSNGTCDPFARVTLNYSSKT-DTKRTKVKKKTNNPRFDEAFYFELTigfsyekksfkveeEDLEKSE 79

                         90       100       110       120       130
                 ....*....|....*....|....*....|....*....|....*....|
gi 755506600 114 LLVTVWNrASETRQHTLIGCMSFGVRSLLTPDKEiSGWYYLLGEDLGRTK 163
Cdd:cd08675   80 LRVELWH-ASMVSGDDFLGEVRIPLQGLQQAGSH-QAWYFLQPREAPGTR 127

circularly permuted first PDZ domain (PDZ1) of Escherichia coli periplasmic serine endoprotease DegP and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 1 of Escherichia coli DegP (also known as heat shock protein DegP and Protease Do) and related domains. DegP belongs to the HtrA family of housekeeping proteases. It acts as a protease, degrading transiently denatured and unfolded or misfolded proteins which accumulate in the periplasm following heat shock or other stress conditions, and as a molecular chaperone at low temperatures. DegP has two PDZ domains in addition to the protease domain; its PDZ1 domain is responsible for identifying the distinct substrate sequences that affect degradation (degron) of the substrate sequence, and its PDZ2 domain is responsible for combining with other DegP monomers to form a stable oligomer structure. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains and as well as those with circular permutations and domain swapping of beta-strands. The canonical PDZ domain contains six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2); arranged as A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F. This DegP family PDZ domain 1 is a circularly permuted PDZ domain which places beta-strand A on the C-terminus. Another permutation exists in the PDZ superfamily which places both beta-strands A and B on the C-terminus.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|...
gi 755506600 220 VDSGGPAERAGLQQLDTVLQLNERPVEHWKcvELAHEIRSCP--SEIILLVWR 270
Cdd:cd10839   32 VLPDSPAAKAGLKAGDVILSLNGKPITSSA--DLRNRVATTKpgTKVELKILR 82

PDZ domain of SH3 and multiple ankyrin repeat domains protein 1 (SHANK1), SHANK2, SHANK3, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of SHANK1, SHANK2, SHANK3, and related domains. SHANK family proteins, SHANK1 (also known as somatostatin receptor-interacting protein, SSTR-interacting protein, SSTRIP), SHANK2 (also known as cortactin-binding protein 1, proline-rich synapse-associated protein 1), and SHANK3 (proline-rich synapse-associated protein 2) are synaptic scaffolding proteins which are highly enriched in the post-synaptic densities of excitatory synapses. They have been implicated in synaptic transmission, synapse formation, synaptic plasticity, and cytoskeletal remodeling, and are regulators of Cav1 calcium current and CREB target expression. Many protein ligands have been identified for the Shank PDZ domain, such as GKAP (also known as SAPAP), betaPIX (a guanine nucleotide exchange factor used by Rho GTPase family members Rac1 and Cdc42), alpha-latrotoxin, neuroligin, group I metabotropic glutamate receptors (mGluRs), and L-type calcium channels. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This SHANK-like family domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged as beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta- strand F.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755506600 196 ITIRRGKDGFGFTI---CCDSPVR-------------VQAVDSGGPAERAGLQQLDTVLQLNERPV---EHWKCVELahe 256
Cdd:cd06746    9 VVLQKGDKGFGFVLrgaKAVGPILeftptpafpalqyLESVDPGGVADKAGLKKGDFLLEINGEDVvkaSHEQVVNL--- 85

                         90
                 ....*....|....*
gi 755506600 257 IRSCPSEIILLVWRV 271
Cdd:cd06746   86 IRQSGNTLVLKVVTV 100

C2 domain first repeat present in Synaptotagmin-like proteins 4 and 5; All Slp members basically share an N-terminal Slp homology domain (SHD) and C-terminal tandem C2 domains (named the C2A domain and the C2B domain) with the SHD and C2 domains being separated by a linker sequence of various length. SHD of Slp (except for the Slp4-SHD) function as a specific Rab27A/B-binding domain. In addition to Slp, rabphilin, Noc2, and Munc13-4 also function as Rab27-binding proteins. It has been demonstrated that Slp4/granuphilin promotes dense-core vesicle exocytosis. The C2A domain of Slp4 is Ca2+ dependent. Slp5 mRNA has been shown to be restricted to human placenta and liver suggesting a role in Rab27A-dependent membrane trafficking in specific tissues. C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. This cd contains the first C2 repeat, C2A, and has a type-I topology.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755506600  37 LKLSIDAQDRVLLLHIIEGKGLMSREPG--ICDPYVKVSLIPEDSQLPCQTTQIIPDCRDPAFHEHFFFPVPEEGDQKR- 113
Cdd:cd04029    6 FSLSYDYKTQSLNVHVKECRNLAYGDEAkkRSNPYVKTYLLPDKSRQSKRKTSIKRNTTNPVYNETLKYSISHSQLETRt 85

                 ....*.
gi 755506600 114 LLVTVW 119
Cdd:cd04029   86 LQLSVW 91

PDZ domain 7 of glutamate receptor-interacting protein 1 (GRIP1) and GRIP2, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) binding proteins GRIP1 (ABP/GRIP2) and GRIP2, and related domains. GRIP1 and GRIP2 each have 7 PDZ domains. The interaction of GRIP1 and GRIP2 with GluA2/3 (AMPAR subunit) regulates AMPAR trafficking and synaptic targeting. GRIP1 has an essential role in regulating AMPAR trafficking during synaptic plasticity and learning and memory. GRIP1 and GRIP2 interact with a variety of other proteins associated with protein trafficking and internalization, for example GRIP1 also interacts with KIF5 (also known as kinesin 1), EphB receptors, scaffold protein liprin-alpha, and the rasGEF GRASP-1. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This GRIP family PDZ7 domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755506600 192 EKLQITIRRGKDG--FGFTIC---CDSPVRVQAVDSGGPAERAGLQQLDTVLQLNERPVEHWKCVELAHEIRSCPSEIIL 266
Cdd:cd06685    2 ELHKVTLYKDSDTedFGFSVSdglYEKGVYVNAIRPGGPADLSGLQPYDRILQVNHVRTRDFDCCLVVPLIAESGDKLEL 81

                 ....
gi 755506600 267 LVWR 270
Cdd:cd06685   82 VVSR 85

PDZ domain of sorting nexin-27 (SNX27), and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of SNX27, and related domains. SNX27 is involved in retrograde transport from endosome to plasma membrane. The PDZ domain of SNX27 links cargo identification to retromer-mediated transport. SNX27 binds to the retromer complex (vacuolar protein sorting 26(VPS26)-VPS29-VPS35), via its PDZ domain binding to VPS26. The SNX27 PDZ domain also binds to cargo including the G-protein-coupled receptors (GPCRs): beta2-adrenergic receptor (beta2AR), beta1AR, parathyroid hormone receptor (PTHR), alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs), NMDA receptors, 5-hydroxytryptamine 4a receptors, frizzled receptors, and somatostatin receptor subtype 5 (SSTR5). Additional binding partners of the SNX27 PDZ domain include G protein-gated inwardly rectifying potassium (Kir3) channels, angiotensin-converting enzyme 2 (ACE2), and PTEN (phosphatase and tensin homolog deleted on chromosome 10); PTEN binding to SNX27 prevents SNX27's association with the retromer complex. SNX27 has been reported to be a host factor needed for efficient entry of an engineered SARS-CoV-2 variant, the spike protein of which contains a deletion at the S1/S2 subunit cleavage site; the PDZ domain of SNX27 binds angiotensin-converting enzyme 2 (ACE2), and may be involved in recycling ACE2 to the plasma membrane, thereby promoting viral entry. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This SNX27-like family domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755506600 196 ITIRRGKDGFGFTiccdspVR----------------------VQAVDSGGPAERAGLQQLDTVLQLNERPVE---HWKC 250
Cdd:cd23070    3 VTIVKSETGFGFN------VRgqvseggqlrsingelyaplqhVSAVLEGGAADKAGVRKGDRILEVNGVNVEgatHKQV 76

                         90
                 ....*....|....*...
gi 755506600 251 VELaheIRSCPSEIILLV 268
Cdd:cd23070   77 VDL---IKSGGDELTLTV 91

Periplasmic serine protease, S1-C subfamily, contain C-terminal PDZ domain [Posttranslational modification, protein turnover, chaperones];

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*...
gi 755506600 215 VRVQAVDSGGPAERAGLQQLDTVLQLNERPVEHWKcvELAHEIRSCP--SEIILLVWR 270
Cdd:COG0265  203 VLVARVEPGSPAAKAGLRPGDVILAVDGKPVTSAR--DLQRLLASLKpgDTVTLTVLR 258

C2 domain second repeat present in Synaptotagmin-like proteins 1-4; All Slp members basically share an N-terminal Slp homology domain (SHD) and C-terminal tandem C2 domains (named the C2A domain and the C2B domain) with the SHD and C2 domains being separated by a linker sequence of various length. Slp1/JFC1 and Slp2/exophilin 4 promote granule docking to the plasma membrane. Additionally, their C2A domains are both Ca2+ independent, unlike the case in Slp3 and Slp4/granuphilin in which their C2A domains are Ca2+ dependent. It is thought that SHD (except for the Slp4-SHD) functions as a specific Rab27A/B-binding domain. In addition to Slps, rabphilin, Noc2, and Munc13-4 also function as Rab27-binding proteins. It has been demonstrated that Slp3 and Slp4/granuphilin promote dense-core vesicle exocytosis. C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements: Type I and Type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including bind phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions. This cd contains the second C2 repeat, C2B, and has a type-I topology.

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                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 755506600  47 VLLLHIIEGKGL-MSREPGICDPYVKVSLIPEDSQLPCQTTQIIPDCRDPAFHEHFFFP--VPEEGDQKRLLVTVWNRAS 123
Cdd:cd04020   28 ELHVWVKEAKNLpALKSGGTSDSFVKCYLLPDKSKKSKQKTPVVKKSVNPVWNHTFVYDgvSPEDLSQACLELTVWDHDK 107

                         90
                 ....*....|....
gi 755506600 124 ETRQHtLIGCMSFG 137
Cdd:cd04020  108 LSSND-FLGGVRLG 120