PDZ domain of protein Lin-7 and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of Lin-7 (also known as LIN-7 or LIN7), and related domains. Lin-7 targets and organize protein complexes to epithelial and synaptic plasma membranes. There are three mammalian Lin-7 homologs: Lin-7A (protein lin-7 homolog A, also known as mammalian lin-seven protein 1 (MALS-1), vertebrate lin-7 homolog 1 (Veli-1), tax interaction protein 33); Lin-7B (also known as MALS-2, Veli-2); and Lin-7C (also known as MALS-3, Veli-3). Lin-7 is involved in localization of the Let-23 growth factor receptor to the basolateral membrane of epithelial cells, in tight junction localization of insulin receptor substrate p53 (IRSp53), in retaining gamma-aminobutyric (GABA) transporter (BGT-1) at the basolateral surface of epithelial cells, and in regulating recruitment of neurotransmitter receptors to the postsynaptic density (PSD). The Lin7 PDZ domain binds Let-23, BGT and beta-catenin, and NMDA (N-methyl-D-aspartate) receptor NR2B. Lin-7 also binds to the PDZ binding motif located in the C-terminal tail of Rhotekin, an effector protein for small GTPase Rho. 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 Lin-7-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 281362512  90 HPRVVELPKTEEGktrpyelriegiplyhktntlivkvyrpriyvsiihliwkalsifnfcfsgLGFNVMGGKEQNSPIY 169
Cdd:cd06796    1 HPRVVELPKTEEG---------------------------------------------------LGFNVMGGKEQNSPIY 29

                         90       100       110       120       130
                 ....*....|....*....|....*....|....*....|....*....|....*..
gi 281362512 170 ISRIIPGGVADRHGGLKRGDQLLSVNGVSVEGENHEKAVELLKQAVGSVKLVVRYTP 226
Cdd:cd06796   30 ISRIIPGGVADRHGGLKRGDQLLSVNGVSVEGEHHEKAVELLKAAQGSVKLVVRYTP 86

PDZ domain of protein Lin-7 and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of Lin-7 (also known as LIN-7 or LIN7), and related domains. Lin-7 targets and organize protein complexes to epithelial and synaptic plasma membranes. There are three mammalian Lin-7 homologs: Lin-7A (protein lin-7 homolog A, also known as mammalian lin-seven protein 1 (MALS-1), vertebrate lin-7 homolog 1 (Veli-1), tax interaction protein 33); Lin-7B (also known as MALS-2, Veli-2); and Lin-7C (also known as MALS-3, Veli-3). Lin-7 is involved in localization of the Let-23 growth factor receptor to the basolateral membrane of epithelial cells, in tight junction localization of insulin receptor substrate p53 (IRSp53), in retaining gamma-aminobutyric (GABA) transporter (BGT-1) at the basolateral surface of epithelial cells, and in regulating recruitment of neurotransmitter receptors to the postsynaptic density (PSD). The Lin7 PDZ domain binds Let-23, BGT and beta-catenin, and NMDA (N-methyl-D-aspartate) receptor NR2B. Lin-7 also binds to the PDZ binding motif located in the C-terminal tail of Rhotekin, an effector protein for small GTPase Rho. 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 Lin-7-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 281362512  90 HPRVVELPKTEEGktrpyelriegiplyhktntlivkvyrpriyvsiihliwkalsifnfcfsgLGFNVMGGKEQNSPIY 169
Cdd:cd06796    1 HPRVVELPKTEEG---------------------------------------------------LGFNVMGGKEQNSPIY 29

                         90       100       110       120       130
                 ....*....|....*....|....*....|....*....|....*....|....*..
gi 281362512 170 ISRIIPGGVADRHGGLKRGDQLLSVNGVSVEGENHEKAVELLKQAVGSVKLVVRYTP 226
Cdd:cd06796   30 ISRIIPGGVADRHGGLKRGDQLLSVNGVSVEGEHHEKAVELLKAAQGSVKLVVRYTP 86

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

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 281362512  152 SGLGFNVMGGKEQ-NSPIYISRIIPGGVADRhGGLKRGDQLLSVNGVSVEGENHEKAVELLKQAVGSVKLVVR 223
Cdd:pfam00595  10 GGLGFSLKGGSDQgDPGIFVSEVLPGGAAEA-GGLKVGDRILSINGQDVENMTHEEAVLALKGSGGKVTLTIL 81

C-terminal processing protease CtpA/Prc, contains a PDZ domain [Posttranslational modification, protein turnover, chaperones];

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 281362512 151 FSGLGFNVmggKEQNSPIYISRIIPGGVADRhGGLKRGDQLLSVNGVSVEGENHEKAVELLKQAVGS-VKLVVR 223
Cdd:COG0793   59 FGGLGAEL---GEEDGKVVVVSVIPGSPAEK-AGIKPGDIILAIDGKSVAGLTLDDAVKLLRGKAGTkVTLTIK 128

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 281362512  169 YISRIIPGGVADRhGGLKRGDQLLSVNGVSVEGENHekavelLKQAVGSVK 219
Cdd:TIGR02037 260 LVAQVLPGSPAEK-AGLKAGDVITSVNGKPISSFAD------LRRAIGTLK 303

PDZ domain of protein Lin-7 and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of Lin-7 (also known as LIN-7 or LIN7), and related domains. Lin-7 targets and organize protein complexes to epithelial and synaptic plasma membranes. There are three mammalian Lin-7 homologs: Lin-7A (protein lin-7 homolog A, also known as mammalian lin-seven protein 1 (MALS-1), vertebrate lin-7 homolog 1 (Veli-1), tax interaction protein 33); Lin-7B (also known as MALS-2, Veli-2); and Lin-7C (also known as MALS-3, Veli-3). Lin-7 is involved in localization of the Let-23 growth factor receptor to the basolateral membrane of epithelial cells, in tight junction localization of insulin receptor substrate p53 (IRSp53), in retaining gamma-aminobutyric (GABA) transporter (BGT-1) at the basolateral surface of epithelial cells, and in regulating recruitment of neurotransmitter receptors to the postsynaptic density (PSD). The Lin7 PDZ domain binds Let-23, BGT and beta-catenin, and NMDA (N-methyl-D-aspartate) receptor NR2B. Lin-7 also binds to the PDZ binding motif located in the C-terminal tail of Rhotekin, an effector protein for small GTPase Rho. 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 Lin-7-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 281362512  90 HPRVVELPKTEEGktrpyelriegiplyhktntlivkvyrpriyvsiihliwkalsifnfcfsgLGFNVMGGKEQNSPIY 169
Cdd:cd06796    1 HPRVVELPKTEEG---------------------------------------------------LGFNVMGGKEQNSPIY 29

                         90       100       110       120       130
                 ....*....|....*....|....*....|....*....|....*....|....*..
gi 281362512 170 ISRIIPGGVADRHGGLKRGDQLLSVNGVSVEGENHEKAVELLKQAVGSVKLVVRYTP 226
Cdd:cd06796   30 ISRIIPGGVADRHGGLKRGDQLLSVNGVSVEGEHHEKAVELLKAAQGSVKLVVRYTP 86

PDZ domain 3 of human discs large homolog 1 (Dlg1), Dlg2, and Dlg4, Drosophila disc large (Dlg), and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 3 of Drosophila Dlg1, human Dlg1, 2, and 4 and related domains. Dlg1 (also known as synapse-associated protein Dlg197; SAP-97), Dlg2 (also known as channel-associated protein of synapse-110; postsynaptic density protein 93, PSD-93), Dlg4 (also known as postsynaptic density protein 95, PSD-95; synapse-associated protein 90, SAP-90) each have 3 PDZ domains and belong to the membrane-associated guanylate kinase family. Dlg1 regulates antigen receptor signaling and cell polarity in lymphocytes, B-cell proliferation and antibody production, and TGFalpha bioavailability; its PDZ3 domain binds pro-TGFalpha, and its PDZ2 domain binds the TACE metalloprotease responsible for cleaving pro-TGFalpha to a soluble form. Dlg2 is involved in N-methyl-D-aspartate (NMDA) receptor signaling, regulating surface expression of NMDA receptors in dorsal horn neurons of the spinal cord; it interacts with NMDA receptor subunits and with Shaker-type K+ channel subunits to cluster into a channel complex. The Dlg4 PDZ1 domain binds NMDA receptors, and its PDZ2 domain binds neuronal nitric oxide synthase (nNOS), forming a complex in neurons. The Drosophila Scribble complex (Scribble, Dlg, and lethal giant larvae) plays a role in apico-basal cell polarity, and in other forms of polarity, including regulation of the actin cytoskeleton, cell signaling and vesicular trafficking, and in tumor development; postsynaptic targeting of Drosophila DLG requires interactions mediated by the first two PDZ domains. 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 Dlg-like family PDZ3 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 281362512 152 SGLGFNVMGGkEQNSPIYISRIIPGGVADRHGGLKRGDQLLSVNGVSVEGENHEKAVELLKQAVGSVKLVVRYTP 226
Cdd:cd06795   12 TGLGFNIVGG-EDGEGIFISFILAGGPADLSGELRRGDQILSVNGVDLRNATHEQAAAALKNAGQTVTIIAQYKP 85

Domain present in PSD-95, Dlg, and ZO-1/2; Also called DHR (Dlg homologous region) or GLGF (relatively well conserved tetrapeptide in these domains). Some PDZs have been shown to bind C-terminal polypeptides; others appear to bind internal (non-C-terminal) polypeptides. Different PDZs possess different binding specificities.

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 281362512   153 GLGFNVMGGKEQNSPIYISRIIPGGVADRHGgLKRGDQLLSVNGVSVEGENHEKAVELLKQAVGSVKLVVRY 224
Cdd:smart00228  13 GLGFSLVGGKDEGGGVVVSSVVPGSPAAKAG-LRVGDVILEVNGTSVEGLTHLEAVDLLKKAGGKVTLTVLR 83

PDZ domain 13 of multi-PDZ-domain protein 1 (MUPP1) and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 13 of MUPP1. MUPP1 and PATJ serve as scaffolding proteins linking different proteins and protein complexes involved in the organization of tight junctions and epithelial polarity. MUPP1 contains an L27 (Lin-2 and Lin-7 binding) domain and 13 PDZ domains. PATJ (also known as INAD-like) contains an L27 domain and ten PDZ domains. PATJ lacks 3 PDZ domains seen in MUPP1: PDZ6, PDZ9, and PDZ13. This MuPP1-like PDZ13 domain is therefore absent from PATJ. MUPP1 and PATJ share several binding partners, including junctional adhesion molecules (JAM), zonula occludens (ZO)-3, Pals1 (protein associated with Lin-7), Par (partitioning defective)-6 proteins, and nectins (adherence junction adhesion molecules). 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 MUPP1-like family PDZ13 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 281362512 153 GLGFNVMGG---KEQNSPIYISRIIPGGVADRHGGLKRGDQLLSVNGVSVEGENHEKAVELLKQAVGSVKLVV 222
Cdd:cd06676   10 GLGFSIVGGfgsPHGDLPIYVKTVFEKGAAAEDGRLKRGDQILAVNGESLEGVTHEEAVNILKKTKGTVTLTV 82

PDZ domain 5 of Danio rerio tyrosine-protein phosphatase non-receptor type 13 (Ptpn13) and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 5 of Danio rerio Ptpn13, and related domains. Protein-tyrosine phosphatases (PTPs) dephosphorylate phosphotyrosyl residues in proteins that are phosphorylated by protein tyrosine kinases (PTKs). Danio rerio Ptpn13 is a classical non-receptor-like PTP. 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 PTPN13-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 281362512 153 GLGFNVMGGkEQNSPIYISRIIPGGVADRHGGLKRGDQLLSVNGVSVEGENHEKAVELLKQAVGSVKLVV 222
Cdd:cd23060   11 GLGFSLVGG-EGGSGIFVKSISPGGVADRDGRLQVGDRLLQVNGESVIGLSHSKAVNILRKAKGTVQLTV 79

PDZ domain of Golgi-associated PDZ and coiled-coil motif-containing protein (GOPC), and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of GOPC and related domains. GOPC, also known as PIST (PDZ domain protein interacting specifically with TC10), FIG (fused in glioblastoma), and CAL (CFTR-associated ligand), regulates the trafficking of a wide array of proteins, including small GTPases, receptors, and cell surface molecules such as cadherin 23 and CFTR. It may regulate CFTR chloride currents and acid-sensing ASIC3 currents by modulating cell surface expression of both channels, and may play a role in autophagy. Interaction partners of the GOPC PDZ domains include: FZD5, FZD8, ASIC3, CFTR, MUC3, ARFRP1, Ggamma13, neuroligin, and Stargazin. 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 GOPC-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 281362512 153 GLGFNVMGGKEQNSPIYISRIIPGGVADRHGGLKRGDQLLSVNGVSVEGENHEKAVELLKQAVGSVKLVVRY 224
Cdd:cd06800   12 GLGISITGGKEHGVPILISEIHEGQPADRCGGLYVGDAILSVNGIDLRDAKHKEAVTILSQQRGEITLEVVY 83

PDZ1 domain of Gallus gallus uncharacterized syntaxin-binding protein 4 (STXBP4) isoform X1, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 1 of Gallus gallus uncharacterized syntaxin-binding protein 4 (STXBP4) isoform X1, and related domains. Gallus gallus STXBP4 isoform X1 contains 2 PDZ domains (PDZ1 and PDZ2). 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 STXBP4-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 281362512 146 IFNFCFSGLGFNVMGGKEQNSP----IYISRIIPGGVADRHGGLKRGDQLLSVNGVSVEGENHEKAVELLKQAVGS--VK 219
Cdd:cd06692    2 EFSDCSKGLGIKIIGGYRENTGeefgIFIKRILPGGLAATDGRLKEGDLILEVNGESLQGVTNERAVSILRSASASnhMS 81

                 ...
gi 281362512 220 LVV 222
Cdd:cd06692   82 LLI 84

PDZ domain 2 of Drosophila Scribble, human Scribble homolog, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 2 of Drosophila Scribble (also known as LAP4), human Scribble homolog (also known as hScrib, LAP4, CriB1, ScrB1 and Vartul), and related domains. They belong to the LAP family, which describes proteins that contain either one or four PDZ domains and 16 LRRs (leucine-rich repeats) and function in controlling cell shape, size and subcellular protein localization. In Drosophila, the Scribble complex, comprising Scribble, discs large, and lethal giant larvae, plays a role in apico-basal cell polarity, in other forms of polarity, including regulation of the actin cytoskeleton, cell signaling and vesicular trafficking, and in tumor development. Mammalian Scribble is important in many aspects of cancer development. Scribble and its homologs can be downregulated or overexpressed in cancer; they have a role in cancer beyond their function in loss of cell polarity. 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 Scribble-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 281362512 153 GLGFNVMGGKEQN------SPIYISRIIPGGVADRHGGLKRGDQLLSVNGVSVEGENHEKAVELLKQAVGSVKLVV 222
Cdd:cd06703   13 GLGFSIAGGKGSTpfrdgdEGIFISRITEGGAADRDGKLQVGDRVLSINGVDVTEARHDQAVALLTSSSPTITLVV 88

PDZ domain 1 of protein tyrosine phosphatase non-receptor type 13 (PTPN13), and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 1 of PTPN13 [also known as Fas-associated protein-tyrosine phosphatase 1 (FAP-1), protein-tyrosine phosphatase 1E (PTP-E1), and protein-tyrosine phosphatase (PTPL1)], and related domains. PTPN13 regulates negative apoptotic signaling and mediates phosphoinositide 3-kinase (PI3K) signaling. PTPN13 has five PDZ domains. Proteins known to interact with PTPN13 PDZ domains include: PLEKHA1 and PLEKHA2 via PTPN13-PDZ domain 1, Fas receptor and thyroid receptor-interacting protein 6 via PTPN13-PDZ domain 2, nerve growth factor receptor and protein kinase N2 via PTPN13-PDZ domain 3, PDZ and LIM domain 4 (PDLIM4) via PTPN13-PDZ domains 2 and 4, and brain calpain-2 via PTPN13-PDZ domains 3, 4 and 5. Calpain-2-mediated PTPN13 fragments may be involved in abnormal tau aggregation and increased risk for Alzheimer's disease. 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 PTPN13 family PDZ1 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 281362512 153 GLGFNVMGGKE---QNSPIYISRIIPGGVADRHGGLKRGDQLLSVNGVSVEGENHEKAVELLKQAVGSVKLVV 222
Cdd:cd23072   14 GLGFQIVGGEKsgrLDLGIFISSITPGGPADLDGRLKPGDRLISVNDVSLEGLSHDAAVEILQNAPEDVTLVV 86

PDZ domain 2 of the canonical isoform 1 of PDZ domain containing 7 (PDZD7), and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 2 of the long isoform 1 of PDZD7, and related domains. PDZD7 is critical for the organization of Usher syndrome type 2 (USH2) complex. Usher syndrome is the leading cause of hereditary sensory deaf-blindness in humans; USH2 is the most common sub-type. Formation of the USH2 complex is based upon heterodimerization between PDZD7 and whirlin (another PDZ domain-containing protein) and a subsequent dynamic interplay between USH2 proteins via their multiple PDZ domains. The PDZD7 PDZ2 domain binds GPR98 (also known as VLGR1) and usherin (USH2A). PDZD7 and whirlin form heterodimers through their multiple PDZ domains; whirlin and PDZD7 interact with usherin and GPR98 to form an interdependent ankle link complex. PDZD7 also interacts with myosin VIIa. PDZD7 also forms homodimers through its PDZ2 domain. Various isoforms of PDZD7 produced by alternative splicing have been identified; this subgroup includes the second PDZ domain of the canonical isoform of PDZD7- isoform 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 PDZD7-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
                 ....*....|....*....|....*....|....*....|....*....|....*....
gi 281362512 154 LGFNVMGGKEQNSPIYISRIIPGGVADRHgGLKRGDQLLSVNGVSVEGENHEKAVELLK 212
Cdd:cd10834   15 LGFNIRGGSEYGLGIYVSKVDPGGLAEQN-GIKVGDQILAVNGVSFEDITHSKAVEVLK 72

PDZ domain 1 of human discs large homolog 1 (Dlg1), Dlg2, and Dlg4, Drosophila disc large (Dlg), and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 1 of Drosophila Dlg1, human Dlg1,2, and 4 and related domains. Dlg1 (also known as synapse-associated protein Dlg197 or SAP-97), Dlg2 (also known as channel-associated protein of synapse-110, postsynaptic density protein 93, or PSD-93), Dlg4 (also known as postsynaptic density protein 95, PSD-95, synapse-associated protein 90, or SAP-90) each have 3 PDZ domains and belong to the membrane-associated guanylate kinase family. Dlg1 regulates antigen receptor signaling and cell polarity in lymphocytes, B-cell proliferation and antibody production, and TGFalpha bioavailability; its PDZ3 domain binds pro-TGFalpha, and its PDZ2 domain binds the TACE metalloprotease responsible for cleaving pro-TGFalpha to a soluble form. Dlg2 is involved in N-methyl-D-aspartate (NMDA) receptor signaling. It regulates surface expression of NMDA receptors in dorsal horn neurons of the spinal cord, and it also interacts with NMDA receptor subunits and with Shaker-type K+ channel subunits to cluster into a channel complex. Dlg4 PDZ1 domain binds NMDA receptors, and its PDZ2 domain binds neuronal nitric oxide synthase (nNOS), forming a complex in neurons. The Drosophila Scribble complex (Scribble, Dlg, and lethal giant larvae) plays a role in apico-basal cell polarity, and in other forms of polarity, including regulation of the actin cytoskeleton, cell signaling and vesicular trafficking, and in tumor development. Postsynaptic targeting of Drosophila DLG requires interactions mediated by the first two PDZ domains. 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 Dlg-like family PDZ1 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 281362512 152 SGLGFNVMGGKEQ-----NSPIYISRIIPGGVADRHGGLKRGDQLLSVNGVSVEGENHEKAVELLKQAVGSVKLVVR 223
Cdd:cd06723   11 SGLGFSIAGGTDNphigdDPSIYITKIIPGGAAAADGRLRVNDIILRVNDVDVRNVTHSVAVEALKEAGSIVRLYVK 87

PDZ domain of PDZ-LIM family proteins, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of PDZ-LIM family proteins including PDLIM1-7, and related domains. PDZ-LIM family proteins (also known as Zasp PDZ domain proteins) are involved in the rearrangement of the actin cytoskeleton; they mediate association with the cytoskeleton through alpha-actinin as well as with other proteins involved in signal transduction pathways. Members of this family include PDLIM1 (also known as C-terminal LIM domain protein 1, elfin, LIM domain protein CLP-36), PDLIM2 (also known as PDZ-LIM protein mystique), PDLIM3 (also known as actinin-associated LIM protein, alpha-actinin-2-associated LIM protein, ALP), PDLIM4 (also known as LIM protein RIL, Reversion-induced LIM protein), PDLIM5 (also known as enigma homolog, ENH, enigma-like PDZ and LIM domains protein), PDLIM6 (also known as LIM domain-binding protein 3, ZASP, Cypher, Oracle), and PDLIM7 (also known as PDZ and LIM domain protein 7, LIM mineralization protein, LMP; protein enigma). PDLIM1 has been shown to negatively regulate NF-kappaB-mediated signaling in the cytoplasm. PDLIM7 negatively regulates p53 through binding murine double minute 2 (MDM2). The PDZ domains of PDZ-LIM family proteins PDLIM1, 2, 3, 5, 6, 7 have been shown to bind actin. Other PDZ-LIM family PDZ domain binding partners include thyroid receptor interacting protein-6 (PDLIM4-PDZ), the LIM domain of PDLIM4 (PDLIM4-PDZ), tropomyosin (PDLIM7-PDZ), myotilin and calsarcin 1 (PDLIM6-PDZ), and proteins from the myotilin and FATZ (calsarcin/myozenin) families (PDLIM1, 3, 4, 6 PDZ domains). 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 PDLIM-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.

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gi 281362512 155 GFNVMGGKEQNSPIYISRIIPGGVADRhGGLKRGDQLLSVNGVSVEGENHEKAVELLKQAVGSVKLVVR 223
Cdd:cd06753   11 GFRLQGGKDFNQPLTISRVTPGGKAAQ-ANLRPGDVILAINGESTEGMTHLEAQNKIKAATGSLSLTLE 78

PDZ domain 3 of human Ligand of Numb protein X 1 (LNX1) and LNX2, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 3 of LNX1 (also known as PDZ domain-containing RING finger protein 2, PDZRN2) and LNX2 (also known as PDZ domain-containing RING finger protein 1, PDZRN1), and related domains. LNX1 and LNX2 are Ring (Really Interesting New Gene) finger and PDZ domain-containing E3 ubiquitin ligases that bind to the cell fate determinant protein NUMB and mediate its ubiquitination. LNX1 can ubiquitinate a number of other ligands including PPFIA1, KLHL11, KIF7 and ERC2. LNX1 and LNX2 each have four PDZ domains. 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 LNX family PDZ3 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.

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gi 281362512 154 LGFNVMGGKEQNS---PIYISRIIPGGVADRHGGLKRGDQLLSVNGVSVEGENHEKAVELLKQAVGSVKLVVR 223
Cdd:cd06679   13 LGISVAGGRGSRRgdlPIYVTNVQPDGCLGRDGRIKKGDVLLSINGISLTNLSHSEAVAVLKASAASSSIVLK 85

PDZ domain 2 of PDZ domain containing 2 (PDZD2), and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 2 of PDZD2, also known as KIAA0300, PIN-1, activated in prostate cancer (AIPC) and PDZ domain-containing protein 3 (PDZK3). PDZD2 has seven PDZ domains, and is expressed at exceptionally high levels in the pancreas and certain cancer tissues such as prostate cancer. It promotes the proliferation of insulinoma cells and is upregulated during prostate tumorigenesis. In osteosarcoma (OS), the microRNA miR-363 acts as a tumor suppressor by inhibiting PDZD2. 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 PDZD2-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.

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gi 281362512 152 SGLGFNVMGGK-EQNSP--IYISRIIPGGVADRHGGLKRGDQLLSVNGVSVEGENHEKAVELLKQAVGSVKLVV 222
Cdd:cd06758   12 GGLGIQITGGKgSKRGDigIFVAGVEEGGSADRDGRLKKGDELLMINGQSLIGLSHQEAVAILRSSASPVQLVI 85

PDZ domain of Rap guanine nucleotide exchange factor 2 and Rap guanine nucleotide exchange factor 6, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of Rap guanine nucleotide exchange factor 2 (RapGEF2, also named RA-GEF-1, PDZ-GEF1, CNrasGEF and nRapGEP) and Rap guanine nucleotide exchange factor 6 (RapGEF6, also named RA-GEF-2 and PDZ-GEF2). RapGEF2 and RapGEF6 constitute a subfamily of guanine nucleotide exchange factors (GEFs) for RAP small GTPases that is characterized by the possession of the PDZ and Ras/Rap-associating domains. They activate Rap small GTPases, by catalyzing the release of GDP from the inactive GDP-bound forms, thereby accelerating GTP loading to yield the active GTP-bound forms. The PDZ domain of RapGEF6 (also known as PDZ-GEF2) binds junctional adhesion molecule A (JAM-A). 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 RapGEF2 and RapGEF6 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.

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gi 281362512 154 LGFNVMGGKEQNSPIYISRIIPGGVADRhGGLKRGDQLLSVNGVSVEGENHEKAVELLK 212
Cdd:cd06755   14 LHFSLLGGSEKGFGIFVSKVEKGSKAAE-AGLKRGDQILEVNGQNFENITLKKALEILR 71

PDZ domain 2 of multi-PDZ-domain protein 1 (MUPP1) and PATJ (protein-associated tight junction) and similar domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 2 of MUPP1 and PATJ, and related domains. MUPP1 and PATJ serve as scaffolding proteins linking different proteins and protein complexes involved in the organization of tight junctions and epithelial polarity. MUPP1 contains an L27 (Lin-2 and Lin-7 binding) domain and 13 PDZ domains. PATJ (also known as INAD-like) contains an L27 domain and ten PDZ domains. MUPP1 and PATJ share several binding partners, including junctional adhesion molecules (JAM), zonula occludens (ZO)-3, Pals1 (protein associated with Lin-7), Par (partitioning defective)-6 proteins, and nectins (adherence junction adhesion molecules). PATJ lacks 3 PDZ domains seen in MUPP1: PDZ6, 9, and 13; consequently, MUPP1 PDZ7 and 8 align with PATJ PDZ6 and 7; and MUPP1 PDZ domains 10-12 align with PATJ PDZ domains 8-10. 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 MUPP1-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

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gi 281362512 152 SGLGFNVMGGKeqNSPIYISRIIPGGVADRHGGLKRGDQLLSVNGVSVEGENHEKAVELLKQAVGSVKLVV 222
Cdd:cd06667   10 SGLGFGIVGGK--STGVVVKTILPGGVADRDGRLRSGDHILQIGDTNLRGMGSEQVAQVLRQCGSHVRLVV 78

PDZ domain 3 of PDZ domain containing 2 (PDZD2), PDZ domain 1 of human pro-interleukin-16 (isoform 1, 1332 AA), and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 3 of PDZD2, also known as KIAA0300, PIN-1, activated in prostate cancer (AIPC) and PDZ domain-containing protein 3 (PDZK3). PDZD2 has seven PDZ domains. PDZD2 is expressed at exceptionally high levels in the pancreas and certain cancer tissues, such as prostate cancer. It promotes the proliferation of insulinoma cells and is upregulated during prostate tumorigenesis. In osteosarcoma (OS), the microRNA miR-363 acts as a tumor suppressor by inhibiting PDZD2. This family also includes the first PDZ domain (PDZ1) of human pro-interleukin-16 (isoform 1, also known as nPro-Il-16; 1332 amino-acid protein). Precursor IL-16 is cleaved to produce pro-IL-16 and mature IL-16 (derived from the C-terminal 121 AA). Pro-IL-16 functions as a regulator of T cell growth; mature IL-16 is a CD4 ligand that induces chemotaxis and CD25 expression in CD4+ T cells. IL-16 bioactivity has been closely associated with the progression of several different cancers. 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 PDZD2-like family PDZ3 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.

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gi 281362512 153 GLGFNVMGGKEqnSP-----IYISRIIPGGVADRHGGLKRGDQLLSVNGVSVEGENHEKAVELLKQA-VGSVKLVVR 223
Cdd:cd06759   13 GLGFSIVGGRD--SPrgpmgIYVKTIFPGGAAAEDGRLKEGDEILEVNGESLQGLTHQEAIQKFKQIkKGLVVLTVR 87

PDZ domain 3 of Drosophila Scribble, human Scribble homolog, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 2 of Drosophila Scribble (also known as LAP4), human Scribble homolog (also known as hScrib, LAP4, CriB1, ScrB1 and Vartul), and related domains. They belong to the LAP family, which describes proteins that contain either one or four PDZ domains and 16 LRRs (leucine-rich repeats) and function in controlling cell shape, size and subcellular protein localization. In Drosophila, the Scribble complex, comprising Scribble, discs large, and lethal giant larvae, plays a role in apico-basal cell polarity, in other forms of polarity, including regulation of the actin cytoskeleton, cell signaling and vesicular trafficking, and in tumor development. Mammalian Scribble is important in many aspects of cancer development. Scribble and its homologs can be downregulated or overexpressed in cancer; they have a role in cancer beyond their function in loss of cell polarity. 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 Scribble-like family PDZ3 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.

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gi 281362512 154 LGFNVMGGKEQNS-------P-IYISRIIPGGVADRhGGLKRGDQLLSVNGVSVEGENHEKAVELLKQAVGSVKLVVR 223
Cdd:cd06702   12 LGLSIVGGSDHSShpfgvdePgIFISKVIPDGAAAK-SGLRIGDRILSVNGKDLRHATHQEAVSALLSPGQEIKLLVR 88

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.

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gi 281362512 155 GFNVMGGKEQNSPIYISRIIPGGVADRHgGLKRGDQLLSVNGVSVEGENHEKAVELLKQAVGSVKLVVR 223
Cdd:cd23068   14 GFRLQGGADFGQPLSIQKVNPGSPADKA-GLRRGDVILRINGTDTSNLTHKQAQDLIKRAGNDLQLTVQ 81

PDZ domain 5 of multi-PDZ-domain protein 1 (MUPP1), PATJ (protein-associated tight junction) and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 5 of MUPP1 and PATJ, and related domains. MUPP1 and PATJ serve as scaffolding proteins linking different proteins and protein complexes involved in the organization of tight junctions and epithelial polarity. MUPP1 contains an L27 (Lin-2 and Lin-7 binding) domain and 13 PDZ domains. PATJ (also known as INAD-like) contains an L27 domain and ten PDZ domains. MUPP1 and PATJ share several binding partners, including junctional adhesion molecules (JAM), zonula occludens (ZO)-3, Pals1 (protein associated with Lin-7), Par (partitioning defective)-6 proteins, and nectins (adherence junction adhesion molecules). PATJ lacks 3 PDZ domains seen in MUPP1: PDZ6, 9, and 13; consequently, MUPP1 PDZ7 and 8 align with PATJ PDZ6 and 7; and MUPP1 PDZ domains 10-12 align with PATJ PDZ domains 8-10. 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 MUPP1-like family PDZ5 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

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gi 281362512 153 GLGFNVMGGKEQNSP----IYISRIIPGGVADRHGGLKRGDQLLSVNGVSVEGENHEKAVELLKQA-VGSVKLVV 222
Cdd:cd06669   19 GLGFSILDYQDPLDPsetvIVIRSLVPGGVAEQDGRLLPGDRLVFVNDVSLENASLDEAVQALKSApPGTVRIGV 93

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.

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gi 281362512 152 SGLGFNVMGGKEQNSPiYISRIIPGGVADRhGGLKRGDQLLSVNGVSVEGENHEKAVELLKQAVGSVKLVV 222
Cdd:cd06768   10 EGYGFNLHAEKGRPGH-FIREVDPGSPAER-AGLKDGDRLVEVNGENVEGESHEQVVEKIKASGNQVTLLV 78

PDZ domain 3 of partitioning defective 3 (Par3), and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 3 of Par3 (or PAR3 or Par-3, also known as Atypical PKC isotype-specific-interacting protein, ASIP, Drosophila Bazooka) and related domains. Par3 is a scaffold protein involved in organizing cell polarity across animals. Par3 binds numerous molecules both for its recruitment to one pole of the cell and for downstream contributions to polarized cell function. It regulates cell polarity by targeting the Par complex proteins Par6 and atypical protein kinase C (aPKC) to specific cortical sites. Physical interactions between Par-3 and the Par complex include Par3 PDZ domain 1 binding to the Par6 PDZ domain, Par3 PDZ domain 1 and PDZ domain 3 binding the Par6's PDZ-binding motif, and an interaction with an undefined region of aPKC that requires both Par3 PDZ2 and PDZ3. The PDZ domains of Par3 have also been implicated as potential phosphoinositide signaling integrators, since its second PDZ domain binds to phosphoinositides, and the third PDZ interacts with phosphoinositide phosphatase PTEN. 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 Par3 family PDZ3 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.

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gi 281362512 153 GLGFNVMGGKEQNSP-------IYISRIIPGGVADRHGGLKRGDQLLSVNGVSVEGENHEKAVELLKQAV-------GSV 218
Cdd:cd23059   17 GLGVSVKGKTSKEDNggkadlgIFIKSIIHGGAASKDGRLRVNDQLIAVNGESLLGLTNSEAMETLRRAMstegnirGMI 96

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gi 281362512 219 KLVV 222
Cdd:cd23059   97 QLVV 100

PDZ domain 4 of membrane-associated guanylate kinase inverted 1 (MAGI-1), MAGI-2, and MAGI-3, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 4 of MAGI1, 2, 3 (MAGI is also known as Membrane-associated guanylate kinase, WW and PDZ domain-containing protein) and related domains. MAGI proteins have been implicated in the control of cell migration and invasion through altering the activity of phosphatase and tensin homolog (PTEN) and modulating Akt signaling. Four MAGI proteins have been identified (MAGI1-3 and MAGIX). MAGI1-3 have 6 PDZ domains and bind to the C-terminus of PTEN via their PDZ2 domain. MAGIX has a single PDZ domain that is related to MAGI1-3 PDZ domain 5. Other binding partners for MAGI1 include JAM4, C-terminal tail of high risk HPV-18 E6, megalin, TRAF6, Kir4.1 (basolateral K+ channel subunit), and cadherin 23; for MAGI2, include DASM1, dendrin, axin, beta- and delta-catenin, neuroligin, hyperpolarization-activated cation channels, beta1-adrenergic receptors, NMDA receptor, and TARPs; and for MAGI3 includes LPA2. 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 MAGI family PDZ4 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.

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gi 281362512 153 GLGFNVMGGKEQNSPIYISRIIPGGVADRHGGLKRGDQLLSVNGVSVEGENHEKAVELLKQAVGSVKLVV 222
Cdd:cd06734   13 GFGFVIISSVNKKSGSKIGRIIPGSPADRCGQLKVGDRILAVNGISILNLSHGDIVNLIKDSGLSVTLTI 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.

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gi 281362512 152 SGLGFnVMGGKEQNSPI-------------YISRIIPGGVADRHGgLKRGDQLLSVNGVSVEGENHEKAVELLKQAVGSV 218
Cdd:cd06746   16 KGFGF-VLRGAKAVGPIleftptpafpalqYLESVDPGGVADKAG-LKKGDFLLEINGEDVVKASHEQVVNLIRQSGNTL 93

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gi 281362512 219 KLVV 222
Cdd:cd06746   94 VLKV 97

PDZ domain 10 of multi-PDZ-domain protein 1 (MUPP1), domain 8 of PATJ (protein-associated tight junction) and similar domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 10 of MUPP1, PDZ domain 8 of PATJ, and related domains. MUPP1 and PATJ serve as scaffolding proteins linking different proteins and protein complexes involved in the organization of tight junctions and epithelial polarity. MUPP1 contains an L27 (Lin-2 and Lin-7 binding) domain and 13 PDZ domains. PATJ (also known as INAD-like) contains an L27 domain and ten PDZ domains. MUPP1 and PATJ share several binding partners, including junctional adhesion molecules (JAM), zonula occludens (ZO)-3, Pals1 (protein associated with Lin-7), Par (partitioning defective)-6 proteins, and nectins (adherence junction adhesion molecules). PATJ lacks 3 PDZ domains seen in MUPP1: PDZ6, 9, and 13; consequently, MUPP1 PDZ7 and 8 align with PATJ PDZ6 and 7; and MUPP1 PDZ domains 10-12 align with PATJ PDZ domains 8-10. 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 MUPP1-like family PDZ10 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.

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gi 281362512 152 SGLGFNVMGGKE-QNSPIYISRIIPGGVADRHGGLKRGDQLLSVNGVSVEGENHEKAVELLKQAVGSVKLVV 222
Cdd:cd06673   13 KGLGLSIVGGSDtLLGAIIIHEVYEDGAAAKDGRLWAGDQILEVNGEDLRKATHDEAINVLRQTPQKVRLLV 84

PDZ domain 3 of the canonical isoform 1 of PDZ domain containing 7 (PDZD7), and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 3 of the long isoform 1 of PDZD7, and related domains. PDZD7 is critical for the organization of the Usher syndrome type 2 (USH2) complex. Usher syndrome is the leading cause of hereditary sensory deaf-blindness in humans; USH2 is the most common sub-type. Formation of the USH2 complex is based upon heterodimerization between PDZD7 and whirlin (another PDZ domain-containing protein) and a subsequent dynamic interplay between USH2 proteins via their multiple PDZ domains. The PDZD7 PDZ2 domain binds GPR98 (also known as VLGR1) and usherin (USH2A). PDZD7 and whirlin form heterodimers through their multiple PDZ domains; whirlin and PDZD7 interact with usherin and GPR98 to form an interdependent ankle link complex. PDZD7 also interacts with myosin VIIa and can also form homodimers through its PDZ2 domain. Various isoforms of PDZD7 produced by alternative splicing have been identified; this subgroup includes the third PDZ domain of the canonical isoform of PDZD7- isoform 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 PDZD7-like family PDZ3 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.

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gi 281362512 152 SGLGFNVMGGKE-QNSP-IYISRIIPGGVADRHGGLKRGDQLLSVNGVSVEGENHEKAVELLKQAvgsvklvvrYTPKVL 229
Cdd:cd06751   11 QSLGISISGGIEsKVQPvVKIEKIFPGGAAALSGNLKAGYELVSVDGESLQQVTHQQAVDIIRRA---------YSNKSK 81

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gi 281362512 230 EEMEMRF 236
Cdd:cd06751   82 EPMEIVV 88

PDZ domain 1 of membrane-associated guanylate kinase inverted 1 (MAGI-1), MAGI-2, and MAGI-3, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 1 of MAGI1, 2, 3 (MAGI is also known as Membrane-associated guanylate kinase, WW and PDZ domain-containing protein) and related domains. MAGI proteins have been implicated in the control of cell migration and invasion through altering the activity of phosphatase and tensin homolog (PTEN) and modulating Akt signaling. Four MAGI proteins have been identified (MAGI1-3 and MAGIX). MAGI1-3 have 6 PDZ domains and bind to the C-terminus of PTEN via their PDZ2 domain. MAGIX has a single PDZ domain that is related to MAGI1-3 PDZ domain 5. Other binding partners for MAGI1 include JAM4, C-terminal tail of high risk HPV-18 E6, megalin, TRAF6, Kir4.1 (basolateral K+ channel subunit), and cadherin 23; for MAGI2, include DASM1, dendrin, axin, beta- and delta-catenin, neuroligin, hyperpolarization-activated cation channels, beta1-adrenergic receptors, NMDA receptor, and TARPs; and for MAGI3 includes LPA2. 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 MAGI family PDZ1 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.

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gi 281362512 153 GLGFNVMGGKEQNSPIYISRIIPGGVADRHGGLKRGDQLLSVNGVSVEGENHEKAVELLkQAV---GSVKLVVR 223
Cdd:cd06731   12 GFGFTIIGGDEPDEFLQIKSVVPDGPAALDGKLRTGDVLVSVNDTCVLGYTHADVVKLF-QSIpigQSVNLEVC 84

PDZ domain of afadin (AFDN), and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of afadin (AFDN, also known as ALL1-fused gene from chromosome 6 protein (AF6) and MLLT4), and related domains. AFDN belongs to the adhesion system, probably together with the E-cadherin-catenin system, that plays a role in the organization of homotypic, interneuronal, and heterotypic cell-cell adherens junctions. The AFDN PDZ domain interaction partners include poliovirus receptor-related protein PRR2/nectin, the junctional adhesion molecule (JAM), the breakpoint-cluster-region protein (BCR), connexin36 (Cx36), and a subset of Eph-related receptor tyrosine kinases; it can also bind low molecular weight ligands, in competition with a natural peptide ligand. Other AFDN-binding proteins have been identified. 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 AFDN 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.

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gi 281362512 152 SGLGFNVM---GGKEQNSPIYISRIIPGGVADRHGGLKRGDQLLSVNGVSVEGENHEKAVELLKQAVGSVKLVVR 223
Cdd:cd06789   13 NGMGLSIVaakGAGQDKLGIYIKSVVKGGAADLDGRLQAGDQLLSVDGHSLVGLSQERAAELMTKTGSVVTLEVA 87

PDZ domain of shroom2, shroom3, shroom4, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of shroom2, shroom3, shroom4, and related domains. Shroom family proteins shroom2 (also known as apical-like protein; protein APXL), shroom3 (also known as shroom-related protein), and shroom4 (also known as second homolog of apical protein) are essential regulators of cell morphology during animal development; they regulate cell architecture by directing the subcellular distribution and activation of Rho kinase (ROCK), which results in the localized activation of non-muscle myosin. The interaction between shroom and ROCK is mediated by the shroom domain 2 (SD2). 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 shroom2,3,4-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.

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gi 281362512 155 GFNVMGGKEQNSPIYISRIIPGGVADRHGGLKRGDQLLSVNGVSVEGENHEkAVELLKQAVGSVKLVVR 223
Cdd:cd06750   14 GFTLKGGLEHGEPLVISKIEEGGKAASVGKLQVGDEVVNINGVPLSGSRQE-AIQLVKGSHKTLKLVVR 81

PDZ domain 4 of Drosophila Scribble, human Scribble homolog, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 4 of Drosophila Scribble (also known as LAP4), human Scribble homolog (also known as hScrib, LAP4, CriB1, ScrB1 and Vartul), and related domains. They belong to the LAP family, which describes proteins that contain either one or four PDZ domains and 16 LRRs (leucine-rich repeats) and function in controlling cell shape, size and subcellular protein localization. In Drosophila, the Scribble complex, comprising Scribble, discs large, and lethal giant larvae, plays a role in apico-basal cell polarity, in other forms of polarity, including regulation of the actin cytoskeleton, cell signaling and vesicular trafficking, and in tumor development. Mammalian Scribble is important in many aspects of cancer development. Scribble and its homologs can be downregulated or overexpressed in cancer; they have a role in cancer beyond their function in loss of cell polarity. 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 Scribble-like family PDZ4 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.

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gi 281362512 154 LGFNVMGG---------KEQNSPIYISRIIPGGVADRHGGLKRGDQLLSVNGVSVEGENHEKAVELLKQAVGSVKLVV 222
Cdd:cd06701   17 LGISIRGGakghagnplDPTDEGIFISKINPDGAAARDGRLKVGQRILEVNGQSLLGATHQEAVRILRSVGDTLTLLV 94

PDZ domain 1 of PDZ domain-containing RING finger protein 4 (PDZRN4), PDZRN3-B, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 1 of PDZRN4, PDZRN3-B, and related domains. PDZRN4 (also known as ligand of numb protein X 4, and SEMACAP3-like protein) contains an N-terminal RING domain and two tandem repeat PDZ domains. It is involved in the progression of cancer, including human liver cancer and breast cancer, and may contribute to the tumorigenesis of rectal adenocarcinoma. Danio rerio PDZRN3-B may participate in neurogenesis: the first PDZ domain of Danio rerio Pdzrn3 interacts with Kidins220 (Kinase D-interacting substrate 220 kD, also named Ankyrin Repeat-Rich Membrane Spanning), a crucial mediator of signal transduction in neural tissues. 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 PDZRN4-like family PDZ1 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.

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gi 281362512 154 LGFNVMGG------KEQNSP--IYISRIIPGGVADRHGGLKRGDQLLSVNGVSVEGENHEKAVELLKQA 214
Cdd:cd06715   14 LGFNIIGGrpcennQEGSSSegIYVSKIVENGPAADEGGLQVHDRIIEVNGKDLSKATHEEAVEAFRTA 82

PDZ domain 1 of inactivation-no-after-potential D (INAD), and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 1 of INAD, and related domains. INAD assembles key enzymes of the Drosophila compound eye photo-transduction pathway into a supramolecular complex, supporting efficient and fast light signaling. It contains 5 PDZ domains arranged in tandem (PDZ1-PDZ5) which independently bind various proteins. INAD PDZ2 binds eye-specific protein kinase C, INAD PDZ3 binds transient receptor potential (TRP) channel, and INAD PDZ4,5 tandem binds NORPA (phospholipase Cbeta, PLCbeta). Mutations of the inaD gene that lead to disruption of each of these interactions impair fly photo signal transduction. 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 INAD-like family PDZ1 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.

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gi 281362512 152 SGLGFNVMGGKEQNSP------IYISRIIPGGVADRHGGLKRGDQLLSVNGVSVEGENHEKAVELLKQAVGSVKLVVR 223
Cdd:cd23063   10 KSFGICIVRGEVKVSPntkttgIFIKGIIPDSPAHKCGRLKVGDRILSVNGNDVRNSTEQAAIDLIKEADFKIVLEIQ 87