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        80
               ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1IU2_A       3 YEEITLERGNSGLGFSIAGGTDNPHIGDDPSIFITKIIPGGAAAQDGRLRVNDSILFVNEVDVREVTHSAAVEALKEAGS 82
Cdd:cd06723  1 YEEITLERGNSGLGFSIAGGTDNPHIGDDPSIYITKIIPGGAAAADGRLRVNDIILRVNDVDVRNVTHSVAVEALKEAGS 80

               ....*....
1IU2_A      83 IVRLYVMRR 91
Cdd:cd06723 81 IVRLYVKRR 89

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        80
               ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1IU2_A       3 YEEITLERGNSGLGFSIAGGTDNPHIGDDPSIFITKIIPGGAAAQDGRLRVNDSILFVNEVDVREVTHSAAVEALKEAGS 82
Cdd:cd06723  1 YEEITLERGNSGLGFSIAGGTDNPHIGDDPSIYITKIIPGGAAAADGRLRVNDIILRVNDVDVRNVTHSVAVEALKEAGS 80

               ....*....
1IU2_A      83 IVRLYVMRR 91
Cdd:cd06723 81 IVRLYVKRR 89

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        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1IU2_A          2 EYEEITLERGNSGLGFSIAGGTDNPHigddpSIFITKIIPGGAAAQDGrLRVNDSILFVNEVDVREVTHSAAVEALKEAG 81
Cdd:smart00228  1 EPRLVELEKGGGGLGFSLVGGKDEGG-----GVVVSSVVPGSPAAKAG-LRVGDVILEVNGTSVEGLTHLEAVDLLKKAG 74

                          90
                  ....*....|
1IU2_A         82 SIVRLYVMRR 91
Cdd:smart00228 75 GKVTLTVLRG 84

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        80
               ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1IU2_A       3 YEEITLERGNSGLGFSIAGGTDNPHIGDDPSIFITKIIPGGAAAQDGRLRVNDSILFVNEVDVREVTHSAAVEALKEAGS 82
Cdd:cd06723  1 YEEITLERGNSGLGFSIAGGTDNPHIGDDPSIYITKIIPGGAAAADGRLRVNDIILRVNDVDVRNVTHSVAVEALKEAGS 80

               ....*....
1IU2_A      83 IVRLYVMRR 91
Cdd:cd06723 81 IVRLYVKRR 89

PDZ domain of synaptojanin-2-binding protein (SYNJ2BP), and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of SYNJ2BP, and related domains. SYNJ2BP (also known as mitochondrial outer membrane protein 25, OMP25) regulates endocytosis of activin type 2 receptor kinases through the Ral/RALBP1-dependent pathway and may be involved in suppression of activin-induced signal transduction. Binding partners of the SYNJ2BP PDZ domain include activin type II receptors (ActR-II), and SYNJ2. SYNJ2BP interacts with the PDZ binding motif of the Notch Delta-like ligand 1 (DLL1) and DLL4, promoting Delta-Notch signaling, and inhibiting sprouting angiogenesis. 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 SYNJ2BP-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
               ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1IU2_A       4 EEITLERGNSGLGFSIAGGTDNPHIGDDPSIFITKIIPGGAAAQDGRLRVNDSILFVNEVDVREVTHSAAVEALKEAGSI 83
Cdd:cd06709  1 EEITLKRGPSGLGFNIVGGTDQPYIPNDSGIYVAKIKEDGAAAIDGRLQEGDKILEINGQSLENLTHQDAVELFRNAGED 80

               ....*
1IU2_A      84 VRLYV 88
Cdd:cd06709 81 VKLKV 85

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.

                       10        20        30        40        50        60        70        80
               ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1IU2_A       5 EITLERG-NSGLGFSIAGGTDnphigDDPSIFITKIIPGGAAAQDGRLRVNDSILFVNEVDVREVTHSAAVEALKEAGSI 83
Cdd:cd00136  1 TVTLEKDpGGGLGFSIRGGKD-----GGGGIFVSRVEPGGPAARDGRLRVGDRILEVNGVSLEGLTHEEAVELLKSAGGE 75

               ....*.
1IU2_A      84 VRLYVM 89
Cdd:cd00136 76 VTLTVR 81

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.

                       10        20        30        40        50        60        70        80
               ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1IU2_A       6 ITLERGNSGLGFSIAGGTDNPhIGDdpsIFITKIIPGGAAAQDGRLRVNDSILFVNEVDVREVTHSAAVEALKEAGSIVR 85
Cdd:cd06673  6 IEINKGKKGLGLSIVGGSDTL-LGA---IIIHEVYEDGAAAKDGRLWAGDQILEVNGEDLRKATHDEAINVLRQTPQKVR 81

               ....*
1IU2_A      86 LYVMR 90
Cdd:cd06673 82 LLVYR 86

PDZ domain 3 of multi-PDZ-domain protein 1 (MUPP1) and 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 3 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 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
               ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1IU2_A       2 EYEEITLERGNSGLGFSIAGGTDNPHIGDDPSIFITKIIPGGAAAQDGRLRVNDSILFVNEVDVREVTHSAAVEALKEAG 81
Cdd:cd06791  1 ETFEVELVKDEQGLGITIAGYVGEKASGELSGIFVKSIIPGSAADQDGRIQVNDQIIAVDGVNLQGFTNQEAVEVLRNTG 80

               ....*....
1IU2_A      82 SIVRLYVMR 90
Cdd:cd06791 81 QVVHLTLAR 89

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        80
               ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1IU2_A       6 ITLERGNSGLGFSIAGGTDNPHiGDDPsIFITKIIPGGAAAQDGRLRVNDSILFVNEVDVREVTHSAAVEALKEAGSIVR 85
Cdd:cd06676  2 ITLERGSDGLGFSIVGGFGSPH-GDLP-IYVKTVFEKGAAAEDGRLKRGDQILAVNGESLEGVTHEEAVNILKKTKGTVT 79

               ....
1IU2_A      86 LYVM 89
Cdd:cd06676 80 LTVL 83

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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               ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1IU2_A       6 ITLERGNSGLGFSIAGGTDNPhigddpSIFITKIIPGGAAAQDGRLRVNDSILFVNEVDVREVTHSAAVEALKEAGSIVR 85
Cdd:cd06795  5 IVLHKGSTGLGFNIVGGEDGE------GIFISFILAGGPADLSGELRRGDQILSVNGVDLRNATHEQAAAALKNAGQTVT 78

               ....*.
1IU2_A      86 LYVMRR 91
Cdd:cd06795 79 IIAQYK 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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               ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1IU2_A       6 ITLERGNSGLGFSIAGgTDNPHIGDDPsIFITKIIPGGAAAQDGRLRVNDSILFVNEVDVREVTHSAAVEALKEA--GSI 83
Cdd:cd23058  8 IQLKKGPEGLGFSITS-RDNPTGGSGP-IYIKNILPKGAAIQDGRLKAGDRLLEVNGVDVTGKTQEEVVSLLRSTklGGT 85

               ....*..
1IU2_A      84 VRLYVMR 90
Cdd:cd23058 86 VSLVVSR 92

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

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                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1IU2_A         5 EITLER-GNSGLGFSIAGGTDNPhigdDPSIFITKIIPGGAAAQDGrLRVNDSILFVNEVDVREVTHSAAVEALKEAGSI 83
Cdd:pfam00595  1 QVTLEKdGRGGLGFSLKGGSDQG----DPGIFVSEVLPGGAAEAGG-LKVGDRILSINGQDVENMTHEEAVLALKGSGGK 75

                 ....*.
1IU2_A        84 VRLYVM 89
Cdd:pfam00595 76 VTLTIL 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.

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               ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1IU2_A      10 RGNSGLGFSIAGGTD---NPHIGDDPSIFITKIIPGGAAAqdGRLRVNDSILFVNEVDVREVTHSAAVEALKEAGSIVRL 86
Cdd:cd06749  6 EKNPGLGFSISGGIGsqgNPFRPDDDGIFVTKVQPDGPAS--KLLQPGDKILEVNGYDFVNIEHGQAVSLLKSFQNTVDL 83

               ....
1IU2_A      87 YVMR 90
Cdd:cd06749 84 VVER 87

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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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1IU2_A          2 EYEEITLERGNSGLGFSIAGGTDNPHigddpSIFITKIIPGGAAAQDGrLRVNDSILFVNEVDVREVTHSAAVEALKEAG 81
Cdd:smart00228  1 EPRLVELEKGGGGLGFSLVGGKDEGG-----GVVVSSVVPGSPAAKAG-LRVGDVILEVNGTSVEGLTHLEAVDLLKKAG 74

                          90
                  ....*....|
1IU2_A         82 SIVRLYVMRR 91
Cdd:smart00228 75 GKVTLTVLRG 84

PDZ domain 5 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 5 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, and belongs to this MAGI1,2,3-like family. 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 PDZ5 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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1IU2_A       6 ITLERGNSGLGFSIAGGTDNPHIGddpsIFITKIIPGGAAAQDGRLRVNDSILFVNEVDVREVTHSAAVEALKEAGSIVR 85
Cdd:cd06735  4 VELERGPKGFGFSIRGGREYNNMP----LYVLRLAEDGPAQRDGRLRVGDQILEINGESTQGMTHAQAIELIRSGGSVVR 79

               ....*.
1IU2_A      86 LyVMRR 91
Cdd:cd06735 80 L-LLRR 84

PDZ domain of tax1-binding protein 3 (TAX1BP3), and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of TAX1BP3, and related domains. TAX1BP3 (also known as glutaminase-interacting protein 3, tax interaction protein 1, TIP-1, tax-interacting protein 1) may regulate a number of protein-protein interactions by competing for PDZ domain binding sites. TAX1BP3 binds beta-catenin and may act as an inhibitor of the Wnt signaling pathway. It competes with LIN7A (also known as Lin-7A or LIN-7A) for inward rectifier potassium channel 4 (KCNJ4) binding, and thereby promotes KCNJ4 internalization. It may play a role in the Rho signaling pathway, and in the activation of CDC42 by the viral protein HPV16 E6. Binding partners of the TAX1BP3 PDZ domain include beta-catenin, KCNJ4, glutaminase liver isoform (GLS2), rho guanine nucleotide exchange factor 16 (ARHGEF16), rhotekin, and CDK5 regulatory subunit-associated protein 3 (also known as LAPZ). 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 TAX1BP3-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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1IU2_A      15 LGFSIAGGTD-----NPHIGDDPSIFITKIIPGGAAAQDGrLRVNDSILFVNEVDVREVTHSAAVEALKEAGSIVRLYVM 89
Cdd:cd10822 15 LGFSIGGGIDqdpskNPFSYTDKGIYVTRVSEGGPAEKAG-LQVGDKILQVNGWDMTMVTHKQAVKRLTKKKPVLRMLVT 93

               .
1IU2_A      90 R 90
Cdd:cd10822 94 R 94

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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                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1IU2_A        1 MEYEEITL---ERGNSGLGFSIAGGTDNPHIGD--DPSIFITKIIPGGAAAQDGRLRVNDSILFVNEVDVREVTHSAAVE 75
Cdd:cd23059   1 REILTFEIplnDTGSAGLGVSVKGKTSKEDNGGkaDLGIFIKSIIHGGAASKDGRLRVNDQLIAVNGESLLGLTNSEAME 80

                        90       100
                ....*....|....*....|...
1IU2_A       76 AL----KEAGSI---VRLYVMRR 91
Cdd:cd23059  81 TLrramSTEGNIrgmIQLVVARR 103

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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               ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1IU2_A       5 EITLERGNS--GLGFSIAGGTDNPH--IGddpsIFITKIIPGGAAAQDGRLRVNDSILFVNEVDVREVTHSAAVEALKEA 80
Cdd:cd06759  2 TIVLMKGAGgkGLGFSIVGGRDSPRgpMG----IYVKTIFPGGAAAEDGRLKEGDEILEVNGESLQGLTHQEAIQKFKQI 77

               ....*....
1IU2_A      81 GS-IVRLYV 88
Cdd:cd06759 78 KKgLVVLTV 86

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.

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               ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1IU2_A       5 EITLER-GNSGLGFSIAGGTDNPhigddpSIFITKIIPGGAAAQDGRLRVNDSILFVNEVDVREVTHSAAVEALKEAGSI 83
Cdd:cd23060  1 QIELEKpANGGLGFSLVGGEGGS------GIFVKSISPGGVADRDGRLQVGDRLLQVNGESVIGLSHSKAVNILRKAKGT 74

               ....*
1IU2_A      84 VRLYV 88
Cdd:cd23060 75 VQLTV 79

PDZ domain 7 of PDZ domain containing 2 (PDZD2), PDZ domain 4 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 7 of PDZD2, also known as KIAA0300, PIN-1, PAPIN, 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 include the PDZ domain of the secreted mature form of human interleukin-16 (IL-16); this is the fourth PDZ domain (PDZ4) of human pro-interleukin-16 (isoform 1, also known as nPro-Il-16). Precursor IL-16 is cleaved to produce pro-IL-16 and C-terminal mature IL-16. 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 PDZ7 domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

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               ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
1IU2_A       4 EEITLERGNSGLGFSIAGGTDNPHiGDDPsIFITKIIPGGAAAQDGRLRVNDSILFVNEVDVREVTHSAAVEALK 78
Cdd:cd06763  2 VTVELEKGSAGLGFSLEGGKGSPL-GDRP-LTIKRIFKGGAAEQSGVLQVGDEILQINGTSLQGLTRFEAWNIIK 74

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.

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               ....*....|....*....|....*....|....*....|....*....|....*....|....*..
1IU2_A      14 GLGFSIAGGTdNPHIGDDPSIFITKIIPGGAAAQDGRLRVNDSILFVNEVDVREVTHSAAVEALKEA 80
Cdd:cd06692  9 GLGIKIIGGY-RENTGEEFGIFIKRILPGGLAATDGRLKEGDLILEVNGESLQGVTNERAVSILRSA 74

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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               ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1IU2_A       6 ITLERGNSGLGFSIAGGTDNPHigDDPSIFITKIIPGGAAAQDGRLRVNDSILFVNEVDVREVTHSAAVEALKEAGSIVR 85
Cdd:cd06758  5 MHLLKEKGGLGIQITGGKGSKR--GDIGIFVAGVEEGGSADRDGRLKKGDELLMINGQSLIGLSHQEAVAILRSSASPVQ 82

               ....*.
1IU2_A      86 LYVMRR 91
Cdd:cd06758 83 LVIASK 88

PDZ domain 7 of multi-PDZ-domain protein 1 (MUPP1), PDZ domain 6 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 7 of MUPP1 and PDZ domain 6 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 PDZ7 domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

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               ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1IU2_A      10 RGNSGLGFSIAGG-TDNPHIGDDPS---IFITKIIPGGAAAQDGRLRVNDSILFVNEVDVREVTHSAAVEALKEAGSIVR 85
Cdd:cd06671 10 EPGKSLGISIVGGrVMGSRLSNGEEirgIFIKHVLEDSPAGRNGTLKTGDRILEVNGVDLRNATHEEAVEAIRNAGNPVV 89

               ...
1IU2_A      86 LYV 88
Cdd:cd06671 90 FLV 92

PDZ domain 3 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 3 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 PDZ3 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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               ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
1IU2_A       5 EITLERGNSGLGFSIAGGTdnphiGDDPSIFITKIIPGGAAAQDGRLRVNDSILFVNEVDVREVTHSAAVEALKEAGSI- 83
Cdd:cd06733  3 TVFLRRQETGFGFRILGGT-----EEGSQVSIGAIVPGGAADLDGRLRTGDELLSVDGVNVVGASHHKVVDLMGNAARNg 77

               ....*...
1IU2_A      84 -VRLYVMR 90
Cdd:cd06733 78 qVNLTVRR 85

PDZ domain 6 of PDZ domain containing 2 (PDZD2), PDZ domain 3 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 6 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 third PDZ domain (PDZ3) of human pro-interleukin-16 (isoform 1, also known as nPro-IL-16). Precursor IL-16 is cleaved to produce pro-IL-16 and C-terminal mature IL-16. 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 PDZ6 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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1IU2_A      12 NSGLGFSIAGGTDNphigDDPSIFITKIIPGGAAAQDGRLRVNDSILFVNEVDVREVTHSAAVEALKEA 80
Cdd:cd06762 11 GSGLGFSLAGGSDL----ENKSITVHRVFPSGLAAQEGTIQKGDRILSINGKSLKGVTHGDALSVLKQA 75

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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1IU2_A       5 EITLERGNS-GLGFSIAGGTDNPHiGDDPsIFITKIIPGGAAAQDGRLRVNDSILFVNEVDVREVTHSAAVEALKEA--G 81
Cdd:cd06679  2 TVTIKKEPSeSLGISVAGGRGSRR-GDLP-IYVTNVQPDGCLGRDGRIKKGDVLLSINGISLTNLSHSEAVAVLKASaaS 79

               ....*....
1IU2_A      82 SIVRLYVMR 90
Cdd:cd06679 80 SSIVLKVLE 88

PDZ domain 5 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 5 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 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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1IU2_A       5 EITLERGNSGLGFSIAGGTDNPHIGddpsIFITKIIPGGAAAQDGRLRVNDSILFVNEVDVREVTHSAAVEALKEAGSIV 84
Cdd:cd06697  5 DITLTCHPGQLGLKLTGGSDSKYQV----IYVLEIVPGSAAAEEGSLQPLDIIHYINGVSTQGMTLEDAVRALEASLPTV 80

               ....*.
1IU2_A      85 RLYVMR 90
Cdd:cd06697 81 VLKATR 86

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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1IU2_A       5 EITLERGNSGLGFSIAGGTDNPHIGDDPsIFITKIIPGGAAAQDGRLRVNDSILFVNEVDVREVTHSAAVEALKEAGS 82
Cdd:cd06681  4 EVTLEKEGNSFGFVIRGGAHEDRNKSRP-LTVTHVRPGGPADREGTIKPGDRLLSVDGISLHGATHAEAMSILKQCGQ 80

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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1IU2_A       4 EEITLERGNSGLGFSIAGGTDNphigddpSIFITKIIPGGAAAQDGRLRVNDSILFVNEVDVREVTHSAAVEALKEAGSI 83
Cdd:cd06667  1 EVIELVNDGSGLGFGIVGGKST-------GVVVKTILPGGVADRDGRLRSGDHILQIGDTNLRGMGSEQVAQVLRQCGSH 73

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1IU2_A      84 VRLYVMR 90
Cdd:cd06667 74 VRLVVAR 80

PDZ domain of segment polarity protein dishevelled homolog DVL1, DVL2, DVL3, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of DVL1-3, and related domains. The dishevelleds (DVL1, 2 and 3 in humans) act downstream of Frizzled (FZD) receptors in both the canonical and non-canonical WNT signaling pathway; they bind the cytoplasmic C-terminus of frizzled family members and transduce the Wnt signal to down-stream effectors. They bind to several proteins known to modulate Wnt signaling. Binding partners of the DVL1 PDZ domain include nucleoredoxin (NXN), Van Gogh-like (VANGL1), Wnt receptor RYK, Dapper 1 (DACT1), Frizzled7 (FZD7), transmembrane protein 88 (TMEM88), Daple (dishevelled-associating protein with a high frequency of leucines), also known as Ccdc88c), and cysteine-rich protein Idax. The DVL2 PDZ domain has been shown to bind the nuclear export signal sequence of the DVL2 protein. 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 DVL-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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1IU2_A      15 LGFSIAGGTDNphiGDDPSIFITKIIPGGAAAQDGRLRVNDSILFVNEVDVREVTHSAAVEALKEA 80
Cdd:cd06717 12 LGISIVGQSNE---RGDGGIYVGSIMKGGAVAADGRIEPGDMILQVNDISFENMSNDDAVRVLREA 74

PDZ domain of neurabin-1 and neurabin-2, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of neurabin-1 (also known as protein phosphatase 1 regulatory subunit 9A) and neurabin-2 (also known as spinophilin, and protein phosphatase 1 regulatory subunit 9B), and related domains. Neurabin-1 and neurabin-2 are neuronal scaffolding proteins that play important roles in the regulation of synaptic transmission through their ability to interact with and target protein phosphatase 1 (PP1) to dendritic spines where PP1 dephosphorylates and inactivates glutamate receptors. Neurabin-2 interacts with multiple other synaptic proteins, including synaptic signaling and scaffolding proteins (e.g., GluN1 and SAPAP3) and cytoskeletal proteins (e.g., neurofilament medium polypeptide, NF-M). Neurabin-1 and neurabin-2 also binds F-actin. Other binding partners of neurabin-1 include adenosine A1 receptor (A1R), SAD-1 kinase and 70 kDa ribosomal protein S6 kinase (p70-S6K). This PDZ domain is immediately C-terminal to the PP1 binding domain. 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 neurabin-like PDZ 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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1IU2_A       5 EITLERGNSGLGFSIAG-GTDNPHIGDDPSIFITKIIPGGAAAQDGRLRVNDSILFVNEVDVREVTHSAAVEALKEAGSI 83
Cdd:cd06790  4 PVELEKGSEGLGISIIGmGVGADAGLEKLGIFVKTVTEGGAAQRDGRIQVNDQIVEVDGISLVGVTQAFAASVLRNTSGT 83

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1IU2_A      84 VRLYVMR 90
Cdd:cd06790 84 VRFLIGR 90

PDZ domain 2 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 2 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 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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1IU2_A      15 LGFSIAGGTDnphigdDPSIFITKIIPGGAAAQDGRLRVNDSILFVNEVDVREVTHSAAVEALKEAGSIVRLYVMR 90
Cdd:cd06678 13 LGIKLVRKKD------EPGVFILDLLEGGLAARDGRLKSDDRVLAINGQDLRHGTPEQAAQIIQASGERVHFVVSR 82