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.

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                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1958646078    1 MIHTKLTVGSLGLGLVIIQNGPYLQ---ISHLINKGAAASDGiLQPGDVLISVGHANVLGYTLREFLKLLQNitIGTVLQ 77
Cdd:smart00228   2 PRLVELEKGGGGLGFSLVGGKDEGGgvvVSSVVPGSPAAKAG-LRVGDVILEVNGTSVEGLTHLEAVDLLKK--AGGKVT 78

                   ....*.
gi 1958646078   78 IKAYRG 83
Cdd:smart00228  79 LTVLRG 84

PDZ domain 2 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 2 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 Par3 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 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 1958646078   2 IHTKLTVGSLGLGLVII-------QNGPYLqISHLINKGAAASDGILQPGDVLISVGHANVLGYTLREFLKLLQNITIGT 74
Cdd:cd23058     6 LHIQLKKGPEGLGFSITsrdnptgGSGPIY-IKNILPKGAAIQDGRLKAGDRLLEVNGVDVTGKTQEEVVSLLRSTKLGG 84

                  ..
gi 1958646078  75 VL 76
Cdd:cd23058    85 TV 86

PDZ domain of neuronal nitric oxide synthase (nNOS), and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 1 of nNOS, and related domains. nNOS produces a key signaling molecule, nitric oxide (NO), which has diverse functions throughout the body and acts as a neurotransmitter and intracellular signaling molecule in the central and peripheral nervous system. nNOS is concentrated at synaptic junctions in the brain and motor endplates in skeletal muscle. The PDZ domain of neuronal nitric oxide synthase (nNOS) interacts with the PDZ domain of alpha1-syntrophin (in muscle cells) and with the second PDZ domain of Disks large homolog 4 (Dlg4, also known as PSD-95), and nitric oxide synthase 1 adaptor protein NOS1AP in neurons. Dlg4 binds NMDA receptors, and nNOS, forming a complex in neurons. NOS1AP competes with Dgl4 for the nNOS PDZ domain and prevents the coupling of nNos activation with NMDA receptor-mediated calcium influx. 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 nNOS-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 1958646078  12 GLGLVIIQ--NGPYLQISHLINKGAAASDGILQPGDVLISVGHANVLGYTLREFLKLLQNITIGT--VLQIKAYRGF 84
Cdd:cd06708    14 GLGFLVKQrvCKPPVIISDLIRGGAAEQSGLVQVGDIILAVNGRPLVDVSYESALEVLRSIPSETpvVLILRGPEGF 90

PDZ domain 1 of protein tyrosine phosphatase non-receptor type 13 (PTPN13),FERM and PDZ domain-containing protein 2 (FRMPD2), 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)], FRMPD2 (also known as PDZ domain-containing protein 4; PDZ domain-containing protein 5C), 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. FRMPD2 is localized in the basolateral membranes of polarized epithelial cells and is associated with tight junction formation and immune response; it contains 3 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 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.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 1958646078  12 GLGLVII------QNGPYLQISHLINKGAAASDGILQPGDVLISVGHANVLGYTLREFLKLLQN 69
Cdd:cd06694    14 GLGFTIVggensgSLDLGIFVKSIIPGGPADKDGRIKPGDRIIAINGQSLEGKTHHAAVEIIQN 77

PDZ domain 2 of glutamate receptor-interacting protein 1 (GRIP1) and GRIP2, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) binding proteins GRIP1 (ABP/GRIP2) and GRIP2, and related domains. GRIP1 and GRIP2 each have 7 PDZ domains. The interaction of GRIP1 and GRIP2 with GluA2/3 (AMPAR subunit) regulates AMPAR trafficking and synaptic targeting. GRIP1 has an essential role in regulating AMPAR trafficking during synaptic plasticity and learning and memory. GRIP1 and GRIP2 interact with a variety of other proteins associated with protein trafficking and internalization, for example GRIP1 also interacts with KIF5 (also known as kinesin 1), EphB receptors, scaffold protein liprin-alpha, and the rasGEF GRASP-1. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This GRIP family 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 1958646078   5 KLTVGSLGLGLVI--------IQNGPyLQISHLINKGAAASDGILQPGDVLISVGHANVLGYTLREFLKLLQNITIGTVL 76
Cdd:cd06681     6 TLEKEGNSFGFVIrggahedrNKSRP-LTVTHVRPGGPADREGTIKPGDRLLSVDGISLHGATHAEAMSILKQCGQEATL 84

                  ..
gi 1958646078  77 QI 78
Cdd:cd06681    85 LI 86

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.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 1958646078   9 GSLGLGLVII-------QNGPyLQISHLINKGAAASDGILQPGDVLISVGHANVLGYTLREFLKLLQNiTIGTV 75
Cdd:cd06676     7 GSDGLGFSIVggfgsphGDLP-IYVKTVFEKGAAAEDGRLKRGDQILAVNGESLEGVTHEEAVNILKK-TKGTV 78

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 1958646078   3 HTKLTVGSLGLGLVIIQ-------NGPYLQISHLINKGAAASDGILQPGDVLISVGHANVLGYTLREFLKLLQNITIGTV 75
Cdd:cd06669    10 VIELEKGDRGLGFSILDyqdpldpSETVIVIRSLVPGGVAEQDGRLLPGDRLVFVNDVSLENASLDEAVQALKSAPPGTV 89

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 1958646078  26 ISHLINKGAAASDGILQPGDVLISVGHANVLGYTLREFLKLLQNI 70
Cdd:cd06701    42 ISKINPDGAAARDGRLKVGQRILEVNGQSLLGATHQEAVRILRSV 86

PDZ domain 4 of PDZ domain containing 2 (PDZD2), PDZ domain 2 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 4 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 second PDZ domain (PDZ2) 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 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 1958646078  10 SLGLGLVII---QNGPYLQISHLINKGAAASDGILQPGDVLISVGHANVLGYTLREFLKLLQNITIGTVLQI 78
Cdd:cd06760    16 GLGIGLCCLpleNDIPGIFIHHLSPGSVAHMDGRLRRGDQILEINGTSLRNVTLNEAYAILSQCKPGPVTLI 87

PDZ domain 11 of MUPP1 of multi-PDZ-domain protein 1 (MUPP1), domain 9 of 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 11 of MUPP1, PDZ domain 9 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 PDZ11 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 1958646078  12 GLGLVII--QNGPYLQISHLINKGAAASDGILQPGDVLISVGHANVLGYTLREFLKLLQNITiGTV 75
Cdd:cd06674    15 GLGLSIVgkRNDTGVFVSDIVKGGAADADGRLMQGDQILSVNGEDVRNASQEAAAALLKCAQ-GKV 79

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.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 1958646078   9 GSLGLGLViiqNGPYLQISH-------LINKGAAASDGILQPGDVLISVGHANVLGYTLREFLKLLQN 69
Cdd:cd06792    12 GSLGISVT---GGINTSVRHggiyvksLVPGGAAEQDGRIQKGDRLLEVNGVSLEGVTHKQAVECLKN 76

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.

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gi 1958646078   9 GSLGLGLVI--------IQNGPYLQISHLINKGAAASDGILQPGDVLISVGHANV 55
Cdd:cd06723     9 GNSGLGFSIaggtdnphIGDDPSIYITKIIPGGAAAADGRLRVNDIILRVNDVDV 63

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 1958646078   7 TVGSLGL---GLVIIQNGPYLQISHLINKGAAASDGILQPGDVLISVGHANVLGYT 59
Cdd:cd06751     9 MKQSLGIsisGGIESKVQPVVKIEKIFPGGAAALSGNLKAGYELVSVDGESLQQVT 64

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.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1958646078   6 LTVGSLGLGLVII----QNGPyLQISHLINKGAAASDGILQPGDVLISVGHANVLGYTLREFLKLLQNiTIGTVLQIKAY 81
Cdd:cd06796     7 LPKTEEGLGFNVMggkeQNSP-IYISRIIPGGVADRHGGLKRGDQLLSVNGVSVEGEHHEKAVELLKA-AQGSVKLVVRY 84

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 1958646078   6 LTVGSLGLGLVII--QNGPYLQISHLINKGAAASDGILQPGDVLISVGHANVLGYTLREFLKLLQNitIGTVLQIKA-YR 82
Cdd:cd06795     7 LHKGSTGLGFNIVggEDGEGIFISFILAGGPADLSGELRRGDQILSVNGVDLRNATHEQAAAALKN--AGQTVTIIAqYK 84

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gi 1958646078  83 gfieiPQEW 91
Cdd:cd06795    85 -----PEEY 88

PDZ domain 4 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 4 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 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 1958646078   4 TKLTVGSLGLGLV--IIQNGPYLqisHLINKGAAASDGILQPGDVLISVGHANVLGYTLREFLKLLQN 69
Cdd:cd06696     9 TKSEKGSLGFTVTkgKDDNGCYI---HDIVQDPAKSDGRLRPGDRLIMVNGVDVTNMSHTEAVSLLRA 73