PDZ domain 2 of PDZ domain-containing RING finger protein 4 (PDZRN4), PDZRN3-B, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 1 of PDZRN4, PDZRN3-B, and related domains. PDZRN4 (also known as ligand of numb protein X 4, and SEMACAP3-like protein) contains an N-terminal RING domain and two tandem repeat PDZ domains. It is involved in the progression of cancer, including human liver cancer and breast cancer, and may contribute to the tumorigenesis of rectal adenocarcinoma. Danio rerio PDZRN3-B may participate in neurogenesis: the first PDZ domain of Danio rerio Pdzrn3 interacts with Kidins220 (Kinase D-interacting substrate 220 kD, also named Ankyrin Repeat-Rich Membrane Spanning), a crucial mediator of signal transduction in neural tissues. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This PDZRN4-like family PDZ2 domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71274176 132 LEYEEVELCKNSHQDKLGLMVCYRTDEEEDLGIYVGEVNPNSIAAKDGRIREGDRIIQINGMDVQNREEAVAILSQEEnT 211
Cdd:cd06716   1 IEYEEVTLKRSNSQEKLGLTLCYRTDDEEDTGIYVSEVDPNSIAAKDGRIREGDQILQINGVDVQNREEAIALLSEEE-K 79

                ....*....
gi 71274176 212 NISLLVARP 220
Cdd:cd06716  80 SITLLVARP 88

PDZ domain 2 of PDZ domain-containing RING finger protein 4 (PDZRN4), PDZRN3-B, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 1 of PDZRN4, PDZRN3-B, and related domains. PDZRN4 (also known as ligand of numb protein X 4, and SEMACAP3-like protein) contains an N-terminal RING domain and two tandem repeat PDZ domains. It is involved in the progression of cancer, including human liver cancer and breast cancer, and may contribute to the tumorigenesis of rectal adenocarcinoma. Danio rerio PDZRN3-B may participate in neurogenesis: the first PDZ domain of Danio rerio Pdzrn3 interacts with Kidins220 (Kinase D-interacting substrate 220 kD, also named Ankyrin Repeat-Rich Membrane Spanning), a crucial mediator of signal transduction in neural tissues. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This PDZRN4-like family PDZ2 domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71274176 132 LEYEEVELCKNSHQDKLGLMVCYRTDEEEDLGIYVGEVNPNSIAAKDGRIREGDRIIQINGMDVQNREEAVAILSQEEnT 211
Cdd:cd06716   1 IEYEEVTLKRSNSQEKLGLTLCYRTDDEEDTGIYVSEVDPNSIAAKDGRIREGDQILQINGVDVQNREEAIALLSEEE-K 79

                ....*....
gi 71274176 212 NISLLVARP 220
Cdd:cd06716  80 SITLLVARP 88

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

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 71274176   157 DEEEDLGIYVGEVNPNSIAAKDGrIREGDRIIQINGMDVQN-REEAVAILSQEENTNISLLVA 218
Cdd:pfam00595  20 SDQGDPGIFVSEVLPGGAAEAGG-LKVGDRILSINGQDVENmTHEEAVLALKGSGGKVTLTIL 81

PDZ domain 1 of PDZ domain-containing RING finger protein 4 (PDZRN4), PDZRN3-B, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 1 of PDZRN4, PDZRN3-B, and related domains. PDZRN4 (also known as ligand of numb protein X 4, and SEMACAP3-like protein) contains an N-terminal RING domain and two tandem repeat PDZ domains. It is involved in the progression of cancer, including human liver cancer and breast cancer, and may contribute to the tumorigenesis of rectal adenocarcinoma. Danio rerio PDZRN3-B may participate in neurogenesis: the first PDZ domain of Danio rerio Pdzrn3 interacts with Kidins220 (Kinase D-interacting substrate 220 kD, also named Ankyrin Repeat-Rich Membrane Spanning), a crucial mediator of signal transduction in neural tissues. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This PDZRN4-like family PDZ1 domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

                        10        20        30
                ....*....|....*....|....*....|....
gi 71274176  18 MLQVNGKELSKLSQEQTLEALRASKEPLVIQVLR 51
Cdd:cd06715  59 IIEVNGKDLSKATHEEAVEAFRTAKEPIVVQVLR 92

PDZ domain 2 of PDZ domain-containing RING finger protein 4 (PDZRN4), PDZRN3-B, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 1 of PDZRN4, PDZRN3-B, and related domains. PDZRN4 (also known as ligand of numb protein X 4, and SEMACAP3-like protein) contains an N-terminal RING domain and two tandem repeat PDZ domains. It is involved in the progression of cancer, including human liver cancer and breast cancer, and may contribute to the tumorigenesis of rectal adenocarcinoma. Danio rerio PDZRN3-B may participate in neurogenesis: the first PDZ domain of Danio rerio Pdzrn3 interacts with Kidins220 (Kinase D-interacting substrate 220 kD, also named Ankyrin Repeat-Rich Membrane Spanning), a crucial mediator of signal transduction in neural tissues. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This PDZRN4-like family PDZ2 domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71274176 132 LEYEEVELCKNSHQDKLGLMVCYRTDEEEDLGIYVGEVNPNSIAAKDGRIREGDRIIQINGMDVQNREEAVAILSQEEnT 211
Cdd:cd06716   1 IEYEEVTLKRSNSQEKLGLTLCYRTDDEEDTGIYVSEVDPNSIAAKDGRIREGDQILQINGVDVQNREEAIALLSEEE-K 79

                ....*....
gi 71274176 212 NISLLVARP 220
Cdd:cd06716  80 SITLLVARP 88

PDZ1 domain of Gallus gallus uncharacterized syntaxin-binding protein 4 (STXBP4) isoform X1, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 1 of Gallus gallus uncharacterized syntaxin-binding protein 4 (STXBP4) isoform X1, and related domains. Gallus gallus STXBP4 isoform X1 contains 2 PDZ domains (PDZ1 and PDZ2). PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This STXBP4-like family domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71274176 145 QDKLGLMVC--YRTDEEEDLGIYVGEVNPNSIAAKDGRIREGDRIIQINGMDVQ--NREEAVAILSQEENTN-ISLLVAR 219
Cdd:cd06692   7 SKGLGIKIIggYRENTGEEFGIFIKRILPGGLAATDGRLKEGDLILEVNGESLQgvTNERAVSILRSASASNhMSLLIAR 86

                ..
gi 71274176 220 PE 221
Cdd:cd06692  87 DE 88

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.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71274176 135 EEVELCKnSHQDKLGLMVCYRTDEEEDLGIYVGEVNPNSIAAKDGRIREGDRIIQINGMDVQNR--EEAVAILSQEENTN 212
Cdd:cd06760   5 MEVTLNK-EPGVGLGIGLCCLPLENDIPGIFIHHLSPGSVAHMDGRLRRGDQILEINGTSLRNVtlNEAYAILSQCKPGP 83

                ....*..
gi 71274176 213 ISLLVAR 219
Cdd:cd06760  84 VTLIISR 90

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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*....
gi 71274176 164 IYVGEVNPNSIAAKDGRIREGDRIIQINGMDVQNR--EEAVAIL-SQEENTNISLLVAR 219
Cdd:cd23058  34 IYIKNILPKGAAIQDGRLKAGDRLLEVNGVDVTGKtqEEVVSLLrSTKLGGTVSLVVSR 92

PDZ domain 1 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 1 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 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
                ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 71274176 161 DLGIYVGEVNPNSIAAKDGRIREGDRIIQINGMDV-QN--REEAVAILsQEENTNISLLVAR 219
Cdd:cd06689  42 ELGIFVQEIQPGSVAARDGRLKENDQILAINGQPLdQSisHQQAIAIL-QQAKGSVELVVAR 102

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

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 71274176   157 DEEEDLGIYVGEVNPNSIAAKDGrIREGDRIIQINGMDVQN-REEAVAILSQEENTNISLLVA 218
Cdd:pfam00595  20 SDQGDPGIFVSEVLPGGAAEAGG-LKVGDRILSINGQDVENmTHEEAVLALKGSGGKVTLTIL 81

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.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|
gi 71274176 148 LGLMVCYRTDEEEDLGIYVGEVNPNSIAAKDGRIREGDRIIQINGMDVQN--REEAVAIL 205
Cdd:cd06717  12 LGISIVGQSNERGDGGIYVGSIMKGGAVAADGRIEPGDMILQVNDISFENmsNDDAVRVL 71

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.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 71274176 161 DLGIYVGEVNPNSIAAKDGRIREGDRIIQINGMDVQNREEAVAI-LSQEENTNISLLVARPES 222
Cdd:cd06694  29 DLGIFVKSIIPGGPADKDGRIKPGDRIIAINGQSLEGKTHHAAVeIIQNAPDKVELIISQPKS 91

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.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71274176 137 VELCKNSHQdKLGLMVCYRTDEEedlGIYVGEVNPNSIAAKDGRIREGDRIIQINGMDVQN-REEAVAILSQEENTNISL 215
Cdd:cd06678   3 VTLNKRDGE-QLGIKLVRKKDEP---GVFILDLLEGGLAARDGRLKSDDRVLAINGQDLRHgTPEQAAQIIQASGERVHF 78

                ....
gi 71274176 216 LVAR 219
Cdd:cd06678  79 VVSR 82

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.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71274176 132 LEYEEVELCKNShqDKLGL-MVCYRTDEEEDLGIYVGEVNPNSIAAKDGRIREGDRIIQINGMDVQN--REEAVAILSQE 208
Cdd:cd06789   1 PEIITVTLKKVG--NGMGLsIVAAKGAGQDKLGIYIKSVVKGGAADLDGRLQAGDQLLSVDGHSLVGlsQERAAELMTKT 78

                        90
                ....*....|.
gi 71274176 209 ENTnISLLVAR 219
Cdd:cd06789  79 GSV-VTLEVAK 88

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

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71274176 111 EYYDP-AEFMegGPQEAERMDELEYEEVELcknshqdkLGLMVcyrtdEEEDLGIYVGEVNPNSIAAKDGrIREGDRIIQ 189
Cdd:COG0793  34 ELGDPhSYYL--DPEEYEDFQESTSGEFGG--------LGAEL-----GEEDGKVVVVSVIPGSPAEKAG-IKPGDIILA 97

                        90       100       110
                ....*....|....*....|....*....|....*
gi 71274176 190 INGMDVQNR--EEAVAILSQEENTNISLLVARPES 222
Cdd:COG0793  98 IDGKSVAGLtlDDAVKLLRGKAGTKVTLTIKRPGE 132

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.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 71274176 137 VELCKNSHQDKLGLMVCYRtdeeedlgIYVGEVNPNSIAAKDGRIREGDRIIQINGMDVQN 197
Cdd:cd06728   3 VTLTKSRKNDEYGLRLGSR--------IFVKEITPDSLAAKDGNLQEGDIILKINGTPVEN 55

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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*..
gi 71274176 151 MVCYRTDEEEDLGIYVGEVNPNSIAAKDGRIREGDRIIQINGMDVQN--REEAVAIL 205
Cdd:cd06671  25 MGSRLSNGEEIRGIFIKHVLEDSPAGRNGTLKTGDRILEVNGVDLRNatHEEAVEAI 81

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

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 71274176 145 QDKLGLMVCYRTDEEEDLGIYVGEVNPNSIAAKDGrIREGDRIIQINGMDVQNREEAVAILSQEENtNISLLVAR 219
Cdd:cd23084   1 LALEGATVSNVTDEDGGKGVVVTEVDPGSPAAQSG-LKKGDVIIGVNRQPVKSIAELRKVLKSKPS-AVLLQIKR 73

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.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71274176 135 EEVELCKNshQDKLGLMVCYRTDE------EEDLGIYVGEVNPNSIAAKDGrIREGDRIIQINGMDVQN--REEAVAILS 206
Cdd:cd06702   1 EEIHLVKA--GGPLGLSIVGGSDHsshpfgVDEPGIFISKVIPDGAAAKSG-LRIGDRILSVNGKDLRHatHQEAVSALL 77

                        90
                ....*....|...
gi 71274176 207 QEENTnISLLVAR 219
Cdd:cd06702  78 SPGQE-IKLLVRH 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
                ....*....|....*....|....*....|....*....|....*....|....*....
gi 71274176 161 DLGIYVGEVNPNSIAAKDGRIREGDRIIQINGMDVQN--REEAVAILsQEENTNISLLV 217
Cdd:cd06676  25 DLPIYVKTVFEKGAAAEDGRLKRGDQILAVNGESLEGvtHEEAVNIL-KKTKGTVTLTV 82

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.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*....
gi 71274176 161 DLGIYVGEVNPNSIAAKDGRIREGDRIIQINGMDVQNRE--EAVAIL-SQEENTNISLL 216
Cdd:cd06765  15 ENGVFISRIVPGSPAAKEGSLTVGDRIIAINGIALDNKSlsECEALLrSCRDSLSLSLM 73

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.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 71274176 161 DLGIYVGEVNPNSIAAKDGRIREGDRIIQINGMDVQN--REEAVAILsQEENTNISLLVARP 220
Cdd:cd06758  28 DIGIFVAGVEEGGSADRDGRLKKGDELLMINGQSLIGlsHQEAVAIL-RSSASPVQLVIASK 88

PDZ domain 2 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 2 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 PDZ2 domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 71274176 137 VELCKNSHQdKLGLMVcyRTDEEEDLGIYVGEVNPNSIAAKDGrIREGDRIIQINGMDVQN--REEAVAILSQE 208
Cdd:cd06741   4 VNLVVEDGQ-SLGLMI--RGGAEYGLGIYVTGVDPGSVAENAG-LKVGDQILEVNGRSFLDitHDEAVKILKSS 73

PDZ domain 5 of Danio rerio tyrosine-protein phosphatase non-receptor type 13 (Ptpn13) and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 5 of Danio rerio Ptpn13, and related domains. Protein-tyrosine phosphatases (PTPs) dephosphorylate phosphotyrosyl residues in proteins that are phosphorylated by protein tyrosine kinases (PTKs). Danio rerio Ptpn13 is a classical non-receptor-like PTP. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This PTPN13-like family domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 71274176 159 EEDLGIYVGEVNPNSIAAKDGRIREGDRIIQINGMDVQ--NREEAVAIL 205
Cdd:cd23060  20 EGGSGIFVKSISPGGVADRDGRLQVGDRLLQVNGESVIglSHSKAVNIL 68

PDZ domain 3 of human discs large homolog 1 (Dlg1), Dlg2, and Dlg4, Drosophila disc large (Dlg), and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 3 of Drosophila Dlg1, human Dlg1, 2, and 4 and related domains. Dlg1 (also known as synapse-associated protein Dlg197; SAP-97), Dlg2 (also known as channel-associated protein of synapse-110; postsynaptic density protein 93, PSD-93), Dlg4 (also known as postsynaptic density protein 95, PSD-95; synapse-associated protein 90, SAP-90) each have 3 PDZ domains and belong to the membrane-associated guanylate kinase family. Dlg1 regulates antigen receptor signaling and cell polarity in lymphocytes, B-cell proliferation and antibody production, and TGFalpha bioavailability; its PDZ3 domain binds pro-TGFalpha, and its PDZ2 domain binds the TACE metalloprotease responsible for cleaving pro-TGFalpha to a soluble form. Dlg2 is involved in N-methyl-D-aspartate (NMDA) receptor signaling, regulating surface expression of NMDA receptors in dorsal horn neurons of the spinal cord; it interacts with NMDA receptor subunits and with Shaker-type K+ channel subunits to cluster into a channel complex. The Dlg4 PDZ1 domain binds NMDA receptors, and its PDZ2 domain binds neuronal nitric oxide synthase (nNOS), forming a complex in neurons. The Drosophila Scribble complex (Scribble, Dlg, and lethal giant larvae) plays a role in apico-basal cell polarity, and in other forms of polarity, including regulation of the actin cytoskeleton, cell signaling and vesicular trafficking, and in tumor development; postsynaptic targeting of Drosophila DLG requires interactions mediated by the first two PDZ domains. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This Dlg-like family PDZ3 domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 71274176 159 EEDLGIYVGEVNPNSIAAKDGRIREGDRIIQINGMDVQ--NREEAVAILSQEENTNISLLVARPE 221
Cdd:cd06795  22 EDGEGIFISFILAGGPADLSGELRRGDQILSVNGVDLRnaTHEQAAAALKNAGQTVTIIAQYKPE 86

permuted PDZ domain of Deg/high-temperature requirement factor A (HtrA) family of housekeeping serine proteases and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of Deg/HtrA-type serine proteases that participate in folding and degradation of aberrant proteins, and in processing and maturation of native proteins. Typically, these proteases have an N-terminal serine protease domain and at least one C-terminal PDZ domain that recognizes substrates, and in some cases activates the protease function. An exception is yeast Nma11p which has two protease domains and four PDZ domains; its N-terminal half is comprised of a protease domain, followed by two PDZ domains, and its C-terminal half has a similar domain arrangement. HtrA-type proteases include the human HtrA1-4 and MBTPS2, tricorn protease, DegS, DegP and C-terminal processing peptidase, cyanobacterial serine proteases Hhoa, HhoB, and HtrA, and yeast Nma11p. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-termini of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains and as well as those with circular permutations and domain swapping of beta-strands. The canonical PDZ domain contains six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2); arranged as A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F. This Deg/HtrA family PDZ domain is a circularly permuted PDZ domain which places beta-strand A at the C-terminus. Another permutation exists in the PDZ superfamily which places both beta-strands A and B on the C-terminus.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 71274176 159 EEDLGIYVGEVNPNSIAAKDGrIREGDRIIQINGMDVQNREEAVAILSQEE-NTNISLLVARPESQL 224
Cdd:cd06779  22 PVNRGVLVAEVIPGSPAAKAG-LKEGDVILSVNGKPVTSFNDLRAALDTKKpGDSLNLTILRDGKTL 87

PDZ domain 12 of multi-PDZ-domain protein 1 (MUPP1), PDZ domain 10 of protein-associated tight junction (PATJ, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 12 of MUPP1, PDZ domain 10 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 PDZ12 family domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71274176 137 VELCKNShQDKLGLMVCY-RTDEEEDLGIYVGEVNPNSIAAKDGRIREGDRIIQINGMDVQN--REEAVAILSQEENTnI 213
Cdd:cd06675   3 VEIKRGP-QDSLGISIAGgVGSPLGDVPVFIAMIQPNGVAAQTGKLKVGDRIVSINGQSTDGltHSEAVNLLKNASGT-I 80

                ....
gi 71274176 214 SLLV 217
Cdd:cd06675  81 ILQV 84

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.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71274176 142 NSHQDKLGLMVCYRTDEEEDlGIYVGEVNPNSIAAKDGRIREGDRIIQINGMDVQNR--EEAVAILsQEENTNISLLVAR 219
Cdd:cd06697   9 TCHPGQLGLKLTGGSDSKYQ-VIYVLEIVPGSAAAEEGSLQPLDIIHYINGVSTQGMtlEDAVRAL-EASLPTVVLKATR 86

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

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 71274176 158 EEEDLGIYVGEVNPNSIAAKDGrIREGDRIIQINGMDVQNRE-EAVAILSQEENTNISLLVA 218
Cdd:cd06768  19 EKGRPGHFIREVDPGSPAERAG-LKDGDRLVEVNGENVEGEShEQVVEKIKASGNQVTLLVV 79

PDZ domain 1 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 1 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 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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 71274176 154 YRTDEEedlGIYVGEVNPNSIAAKDGrIREGDRIIQINGMDVQNRE--EAVAILSQEENTnISLLVAR 219
Cdd:cd06704  25 YKGDDE---GIFISRVTEGGPAAKAG-VRVGDKLLEVNGVDLVDADhhEAVEALKNSGNT-VTMVVLR 87

PDZ domain 8 of multi-PDZ-domain protein 1 (MUPP1), PDZ domain 7 of protein-associated tight junction (PATJ), PDZ domain 2 of Drosophila melanogaster inactivation-no-after-potential D (INAD), and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 8 of MUPP1, PDZ domain 7 of PATJ, and PDZ domain 2 of Drosophila melanogaster INAD, 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. INAD assembles key enzymes of the Drosophila compound eye photo-transduction pathway into a supramolecular complex, supporting efficient and fast light signaling. It contains 5 PDZ domains arranged in tandem (PDZ1-PDZ5) which independently bind various proteins. INAD PDZ2 binds eye-specific protein kinase C. 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 PDZ8 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 71274176 164 IYVGEVNPNSIAAKDGRIREGDRIIQINGMDVQNR--EEAVAIL 205
Cdd:cd06672  28 VFVVGIDPDGAAGKDGRIQVGDELLEINGQVLYGRshLNASAII 71

PDZ domain 2 of multi-PDZ-domain protein 1 (MUPP1) and PATJ (protein-associated tight junction) and similar domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 2 of MUPP1 and PATJ, and related domains. MUPP1 and PATJ serve as scaffolding proteins linking different proteins and protein complexes involved in the organization of tight junctions and epithelial polarity. MUPP1 contains an L27 (Lin-2 and Lin-7 binding) domain and 13 PDZ domains. PATJ (also known as INAD-like) contains an L27 domain and ten PDZ domains. MUPP1 and PATJ share several binding partners, including junctional adhesion molecules (JAM), zonula occludens (ZO)-3, Pals1 (protein associated with Lin-7), Par (partitioning defective)-6 proteins, and nectins (adherence junction adhesion molecules). PATJ lacks 3 PDZ domains seen in MUPP1: PDZ6, 9, and 13; consequently, MUPP1 PDZ7 and 8 align with PATJ PDZ6 and 7; and MUPP1 PDZ domains 10-12 align with PATJ PDZ domains 8-10. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This MUPP1-like family PDZ2 domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*....
gi 71274176 163 GIYVGEVNPNSIAAKDGRIREGDRIIQINGMDVQ--NREEAVAILSQEENTnISLLVAR 219
Cdd:cd06667  23 GVVVKTILPGGVADRDGRLRSGDHILQIGDTNLRgmGSEQVAQVLRQCGSH-VRLVVAR 80

PDZ domain of PDZ domain-containing protein 11, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of PDZD11, and related domains. PDZD11 (also known as ATPase-interacting PDZ protein, plasma membrane calcium ATPase-interacting single-PDZ protein, PMCA-interacting single-PDZ protein, PISP) is involved in the dynamic assembly of apical junctions (AJs). It is recruited by PLEKHA7 to AJs to promote the efficient junctional recruitment and stabilization of nectins, and the efficient early phases of assembly of AJs in epithelial cells. The PDZD11 PDZ domain binds nectin-1 and nectin-3. PDZD11 also binds to a PDZ binding motif located in the C-terminal tail of the human sodium-dependent multivitamin transporter, to the cytoplasmic tail of the Menkes copper ATPase ATP7A, and to the cytoplasmic tail of all plasma membrane Ca2+-ATPase b-splice variants. 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 PDZD11-like family domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 71274176 146 DKLGLMVcyRTDEEEDLGIYVGEVNPNSIAAKDGrIREGDRIIQINGMDVQNRE--EAVAILsqEENTNISLLV 217
Cdd:cd06752  11 EQLGFNI--RGGKASGLGIFISKVIPDSDAHRLG-LKEGDQILSVNGVDFEDIEhsEAVKVL--KTAREIQMRV 79

circularly permuted PDZ domains of Escherichia coli Regulator of sigma-E protease (RseP) and related domains; Permuted PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of ResP (also known as Site-2 protease RseP, and YaeL), and related domains. RseP is involved in the regulation of an extracytoplasmic stress response through the cleavage of membrane-spanning anti-stress-response transcription factor (anti-sigmE) protein RseA; it cleaves the peptide bond between the critical alanine and cysteine in the transmembrane region of RseA, releasing the cytoplasmic domain of RseA with its associated sigmaE. RseP contains two tandem-arranged periplasmic PDZ domains (PDZ-N/PDZ1 and PDZ-C/PDZ2) which act to negatively regulate protease action on intact RseA; they serve as a size-exclusion filter which prevents the access of an intact RseA into the active site of RseP. PDZ domains usually bind in sequence-specific manner to short peptide sequences located at the C-terminal of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains and as well as those with circular permutations and domain swapping of beta-strands. The canonical PDZ domain contains six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2); arranged as beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F. This RseP family PDZ domain is a circularly permuted PDZ domain which places both beta-strands A and B at the C-terminus. Another permutation exists in the PDZ superfamily which places beta-strand A at the C-terminus.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 71274176 166 VGEVNPNSIAAKDGrIREGDRIIQINGMDVQNREEAVAILSQEENTNISLLVAR 219
Cdd:cd23081   3 VGEVVANSPAAEAG-LKPGDRILKIDGQKVRTWEDIVRIVRENPGKPLTLKIER 55

PDZ domain 9 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 9 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 PDZ9 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 PDZ9 domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 71274176 137 VELCKNshQDKLGLMVCyrtDEEEDLGIYVGEVNPNSIAAKDGRIREGDRIIQINGMDVQNR--EEAVAILSQEENT 211
Cdd:cd10817   2 VELPKD--QGGLGIAIS---EEDTENGIVIKSLTEGGPAAKDGRLKVGDQILAVDDESVVGCpyEKAISLLKTAKGT 73

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.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 71274176 136 EVELCKNShqDKLGLMVC---YRTDE-EEDLGIYVGEVNPNSIAAKDGRIREGDRIIQING 192
Cdd:cd06790   4 PVELEKGS--EGLGISIIgmgVGADAgLEKLGIFVKTVTEGGAAQRDGRIQVNDQIVEVDG 62

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.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 71274176 137 VELCKNSHQDKLGLMVcyRTDEEEDLGIYVGEVNPNSIAAKDGrIREGDRIIQING---MDVQNrEEAVAIL 205
Cdd:cd06740   4 VTLKRSKSHEGLGFSI--RGGAEHGVGIYVSLVEPGSLAEKEG-LRVGDQILRVNDvsfEKVTH-AEAVKIL 71

PDZ domain 1 of 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 FRMPD2 (also known as PDZ domain-containing protein 4, and related domains. 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.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 71274176 161 DLGIYVGEVNPNSIAAKDGRIREGDRIIQINGMDVQ--NREEAVAILsQEENTNISLLVARPE 221
Cdd:cd23071  29 DLGIFIASIIPGGPAEKDGRIKPGGRLISLNNISLEgvTFNTAVKIL-QNSPDEVELIISQPK 90