canonical PDZ domain; Canonical PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain. PDZ domains usually bind to short specific peptide sequences located at the C-terminal end of their partner proteins known as PDZ binding motifs. These domains can also interact with internal peptide motifs and certain lipids, and can take part in a head-to-tail oligomerization with other PDZ domains. The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. The canonical PDZ domain contains 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 808354831  12 GIFVDYIHPDSPQSTHLREGDRLLRCNKISLRAVSVDQAASIFRfwmSRSDSLTLLIER 70
Cdd:cd06749   32 GIFVTKVQPDGPASKLLQPGDKILEVNGYDFVNIEHGQAVSLLK---SFQNTVDLVVER 87

PDZ domain of densin, erbin, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of densin, erbin, and related domains. Densin (also known as leucine-rich repeat-containing protein 7, LRRC7, densin-180, protein LAP1) and erbin (also known as densin-180-like protein, Erbb2-interacting protein, protein LAP2) belong to the LAP (leucine-rich repeat and PDZ domain) family of scaffolding proteins that play roles in the maintenance of cell shape and apical-basal polarity. Densin and erbin are components of the excitatory postsynaptic compartment and are regulators of dendritic morphology and postsynaptic structure. The densin PDZ domain binds CaV1.3 alpha1 subunit, delta-catenin, and MAGUIN-1. Binding partners of the erbin PDZ domain include ErbB receptor tyrosine kinase ErbB2, HTLV-1 Tax1, Cav1.3 Ca2+channels, and constituents of the cadherin:catenin cell adhesion complex, in particular delta-catenin, p0071 and ARVCF. The erbin PDZ domain binds Smad3, a transductor of the TGFbeta pathway, possibly by a novel interface of binding. Erbin and two other LAP proteins (scribble and lano) redundantly regulate epithelial polarity and apical adhesion complex. 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 densin and erbin-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
                 ....*....|....*....|....*....|....*....|....*....|....*....
gi 808354831  12 GIFVDYIHPDSPQSTHLREGDRLLRCNKISLRAVSVDQAASIFRfwmSRSDSLTLLIER 70
Cdd:cd06749   32 GIFVTKVQPDGPASKLLQPGDKILEVNGYDFVNIEHGQAVSLLK---SFQNTVDLVVER 87

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

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 808354831    5 MVGSRSRGIFVDYIHPDSP-QSTHLREGDRLLRCNKISLRAVSVDQAASIFRfwmSRSDSLTLLIE 69
Cdd:pfam00595  19 GSDQGDPGIFVSEVLPGGAaEAGGLKVGDRILSINGQDVENMTHEEAVLALK---GSGGKVTLTIL 81

PDZ domain of densin, erbin, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of densin, erbin, and related domains. Densin (also known as leucine-rich repeat-containing protein 7, LRRC7, densin-180, protein LAP1) and erbin (also known as densin-180-like protein, Erbb2-interacting protein, protein LAP2) belong to the LAP (leucine-rich repeat and PDZ domain) family of scaffolding proteins that play roles in the maintenance of cell shape and apical-basal polarity. Densin and erbin are components of the excitatory postsynaptic compartment and are regulators of dendritic morphology and postsynaptic structure. The densin PDZ domain binds CaV1.3 alpha1 subunit, delta-catenin, and MAGUIN-1. Binding partners of the erbin PDZ domain include ErbB receptor tyrosine kinase ErbB2, HTLV-1 Tax1, Cav1.3 Ca2+channels, and constituents of the cadherin:catenin cell adhesion complex, in particular delta-catenin, p0071 and ARVCF. The erbin PDZ domain binds Smad3, a transductor of the TGFbeta pathway, possibly by a novel interface of binding. Erbin and two other LAP proteins (scribble and lano) redundantly regulate epithelial polarity and apical adhesion complex. 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 densin and erbin-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
                 ....*....|....*....|....*....|....*....|....*....|....*....
gi 808354831  12 GIFVDYIHPDSPQSTHLREGDRLLRCNKISLRAVSVDQAASIFRfwmSRSDSLTLLIER 70
Cdd:cd06749   32 GIFVTKVQPDGPASKLLQPGDKILEVNGYDFVNIEHGQAVSLLK---SFQNTVDLVVER 87

PDZ domain 2 of tyrosine kinase PTPN13, FERM and PDZ domain-containing protein 2 (FRMPD2), and similar domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 2 of human PTPN13, and related domains. PTPN13, also known as Fas-associated protein-tyrosine phosphatase 1 (FAP-1), protein-tyrosine phosphatase 1E (PTP-E1), and protein-tyrosine phosphatase (PTPL1), negatively regulates FAS-mediated apoptosis and NGFR-mediated pro-apoptotic signaling, and may also regulate phosphoinositide 3-kinase (PI3K) signaling. It contains 5 PDZ domains; interaction partners of its second PDZ domain (PDZ2) include the Fas receptor (TNFRSF6) and thyroid receptor-interacting protein 6 (TRIP6). The second PDZ (PDZ2) domain, but not PDZ1 or PDZ3, of FRMPD2 binds to GluN2A and GluN2B, two subunits of N-methyl-d-aspartic acid (NMDA) receptors. Other binding partners of the FRMPDZ2 PDZ2 domain include NOD2, and catenin family members, delta catenin (CTNND2), armadillo repeat gene deleted in velo-cardio-facial syndrome (ARVCF) and p0071 (also known as plakophilin 4; PKP4). 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 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
                 ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 808354831   9 RSRGIFVDYIHPDSP--QSTHLREGDRLLRCNKISLRAVSVDQAASIFRfwmSRSDSLTLLIER 70
Cdd:cd06792   27 RHGGIYVKSLVPGGAaeQDGRIQKGDRLLEVNGVSLEGVTHKQAVECLK---NAGQVVTLVLER 87

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 808354831   3 FRMVGSRSRGIFVDYIHPDSP--QSTHLREGDRLLRCNKISLRAVSVDQAASIFR 55
Cdd:cd06667   14 FGIVGGKSTGVVVKTILPGGVadRDGRLRSGDHILQIGDTNLRGMGSEQVAQVLR 68

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 808354831  12 GIFVDYIHPDSPQSTH--LREGDRLLRCNKISLRAVSVDQAASIFRfwmSRSDSLTLLI 68
Cdd:cd06701   39 GIFISKINPDGAAARDgrLKVGQRILEVNGQSLLGATHQEAVRILR---SVGDTLTLLV 94

PDZ domain 4 of Discs Large 5 (Dlg5) and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 4 of Drosophila and mammalian Dlg5, and related domains. Dlg5 is a scaffold protein with multiple conserved functions that are independent of each other in regulating growth, cell polarity, and cell adhesion. It has a coiled-coil domain, 4 PDZ domains and a MAGUK domain (an SH3 domain next to a non-catalytically active guanylate kinase domain). Deregulation of Dlg5 has been implicated in the malignancy of several cancer types. 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 Dlg5-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 808354831   1 MAFRMVGSRSRGIFVDYIHPDSPQSTH--LREGDRLLRCNKISLRAVSVDQAA 51
Cdd:cd06766   14 LGIQLCGGNLHGIFVEDVEDDSPAKGPdgLVPGDLILEYNSVDMRNKTAEEAY 66

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.

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gi 808354831   1 MAFRMVGSR-SRGIFVDYIHPDSPQ--STHLREGDRLLRCNKISLRAVSVDQAASIFR 55
Cdd:cd06795   14 LGFNIVGGEdGEGIFISFILAGGPAdlSGELRRGDQILSVNGVDLRNATHEQAAAALK 71

PDZ domain 3 of Zonula Occludens-1 (ZO-1), homologs ZO-2 and ZO-3, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 3 of ZO-1, -2, -3 and related domains. Zonula occludens proteins (ZO-1, ZO-2, ZO-3) are multi-PDZ domain proteins involved in the maintenance and biogenesis of multi-protein networks at the cytoplasmic surface of intercellular contacts in epithelial and endothelial cells. They have three N-terminal PDZ domains, PDZ1-3, followed by a Src homology-3 (SH3) domain and a guanylate kinase (GuK)-like domain. Among protein-protein interactions for all ZO proteins is the binding of the first PDZ domain (PDZ1) to the C-termini of claudins , and the homo- and hetero-dimerization of ZO-proteins via their second PDZ domain (PDZ2), which takes place by symmetrical domain swapping of the first two beta-strands of PDZ2. At the cell level, ZO-1 and ZO-2 are involved in polarity maintenance, gene transcription, cell proliferation, and tumor cell metastasis. 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 ZO 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
                 ....*....|....*....|....*....|....*....|....*....
gi 808354831   4 RMVGSRSRGIFVDYIHPDSPQSTH-LREGDRLLRCNKISLRAVSVDQAA 51
Cdd:cd06729   16 RLAGGNDVGIFVAGVQEGSPAEKQgLQEGDQILKVNGVDFRNLTREEAV 64

PDZ domain of Ras-associating and dilute domain-containing protein (Radil) and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 1 of Radil (also known as protein KIAA1849) and related domains. Radil is required for cell adhesion and migration of neural crest precursors during development. Radil is a component of a Rasip1-Radil-ARHGAP29 complex at endothelial cell-cell junctions. Rap1, via its effectors Radil and Rasip1 and their binding partner ArhGAP29, controls the endothelial barrier by decreasing Rho-mediated radial tension on cell-cell junctions. ArhGAP29 binds the Radil PDZ domain. The Radil PDZ domain also binds kinesin family protein 14 (KIF14); KIF14 negatively regulates Rap1-mediated inside-out integrin activation by tethering Radil on microtubules. 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 Radil-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 808354831   9 RSRGIFVDYIHPDSP--QSTHLREGDRLLRCNKISLRAVSVDQAASIFRfwmSRSDSLTLLIER 70
Cdd:cd06690   28 RSPGIYIRTLVPDSPaaRDGRLRLGDRILAVNGTSLVGADYQSAMDLIR---TSGDKLRFLVAK 88

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

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 808354831    5 MVGSRSRGIFVDYIHPDSP-QSTHLREGDRLLRCNKISLRAVSVDQAASIFRfwmSRSDSLTLLIE 69
Cdd:pfam00595  19 GSDQGDPGIFVSEVLPGGAaEAGGLKVGDRILSINGQDVENMTHEEAVLALK---GSGGKVTLTIL 81

PDZ domain 1 of the full-length isoform of whirlin and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 1 of the full-length isoform of whirlin and related domains. Whirlin is an essential protein for developmental pathways in photoreceptor cells of the retina and hair cells of the inner ear. The full-length whirlin isoform has two harmonin N-like domains, three PDZ domains, a proline-rich region, and a PDZ-binding motif. Whirlin isoforms may form different complexes at the periciliary membrane complex (PMC) in photoreceptors, and the stereociliary tip and base in inner ear hair cells. It interacts with ADGRV1 and usherin at the PMC; with SANS and RpgrORF15 at the connecting cilium in photoreceptors; with EPS8, MYO15A, p55, and CASK proteins at the stereociliary tip of inner ear hair cells; and with ADGRV1, usherin, and PDZD7 at the stereociliary base in inner ear hair cells. Mutations in the gene encoding whirlin (WHRN; also known as USH2D and DFNB31), have been found to cause either USH2 subtype (USH2D) or autosomal recessive non-syndromic deafness type 31 (DFNB31). Whirlin is the key protein in the USH2 complex (whirlin, usherin and GPR98) which recruits other USH2 causative proteins at the periciliary membrane in photoreceptors and the ankle link of the stereocilia in hair cells. Whirlin's interaction with espin, another stereociliary protein, may be important for the architecture of the USH2 complex. 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 whirlin 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 808354831  12 GIFVDYIHPDS-PQSTHLREGDRLLRCNKISLRAVSVDQAASIFR 55
Cdd:cd06740   28 GIYVSLVEPGSlAEKEGLRVGDQILRVNDVSFEKVTHAEAVKILR 72

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 808354831   7 GSRSRGIFVDYIHPDSPQS-THLREGDRLLRCNKISLRAVSVDQAASIFrfwMSRSDSLTLLIER 70
Cdd:cd06702   28 GVDEPGIFISKVIPDGAAAkSGLRIGDRILSVNGKDLRHATHQEAVSAL---LSPGQEIKLLVRH 89

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 808354831   2 AFRMVGSRSRGIFVDYIHPDSP--QSTHLREGDRLLRCNKISLRAVSVDQAASIfrfwMSRSDS 63
Cdd:cd06789   21 AAKGAGQDKLGIYIKSVVKGGAadLDGRLQAGDQLLSVDGHSLVGLSQERAAEL----MTKTGS 80

PDZ domain 2 of Zonula Occludens-1 (ZO-1), ZO-2 and ZO-3, and related domains; form domain-swapping dimers; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 2 of ZO-1, -2, -3 and related domains. Zonula occludens proteins (ZO-1, ZO-2, ZO-3) are multi-PDZ domain proteins involved in the maintenance and biogenesis of multi-protein networks at the cytoplasmic surface of intercellular contacts in epithelial and endothelial cells. They have three N-terminal PDZ domains, PDZ1-3, followed by a Src homology-3 (SH3) domain and a guanylate kinase (GuK)-like domain. Among protein-protein interactions for all ZO proteins is the binding of the first PDZ domain (PDZ1) to the C-termini of claudins , and the homo- and hetero-dimerization of ZO-proteins via their second PDZ domain (PDZ2), which takes place by symmetrical domain swapping of the first two beta-strands of PDZ2. At the cell level, ZO-1 and ZO-2 are involved in polarity maintenance, gene transcription, cell proliferation, and tumor cell metastasis. 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 ZO 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 808354831   6 VGSRsrgIFVDYIHPDSP--QSTHLREGDRLLRCNKISLRAVSVDQAasifRFWMSRS-DSLTLLIER 70
Cdd:cd06728   18 LGSR---IFVKEITPDSLaaKDGNLQEGDIILKINGTPVENLSLSEA----KKLIEKSkDKLQLVVLR 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 808354831   3 FRMVGSR-----SRGIFVDYIHPD--SPQSTHLREGDRLLRCNKISLRAVSVDQAASIFRfwMSRSDSLTLLI 68
Cdd:cd06759   16 FSIVGGRdsprgPMGIYVKTIFPGgaAAEDGRLKEGDEILEVNGESLQGLTHQEAIQKFK--QIKKGLVVLTV 86

PDZ domain 2 of Discs Large 5 (Dlg5) and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 2 of Drosophila and mammalian Dlg5, and related domains. Dlg5 is a scaffold protein with multiple conserved functions that are independent of each other in regulating growth, cell polarity, and cell adhesion. It has a coiled-coil domain, 4 PDZ domains and a MAGUK domain (an SH3 domain next to a non-catalytically active guanylate kinase domain). Deregulation of Dlg5 has been implicated in the malignancy of several cancer types. 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 Dlg5-like family PSZ2 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 808354831  12 GIFVDYIHPDSPQSTH--LREGDRLLRCNKISLRAVSVDQAASIFRfwmSRSDSLTLLIER 70
Cdd:cd06765   17 GVFISRIVPGSPAAKEgsLTVGDRIIAINGIALDNKSLSECEALLR---SCRDSLSLSLMK 74