GIPC-homology 2 (GH2) domain found in the GIPC family; The GIPC family includes PDZ domain-containing proteins, GIPC1 (also called GAIP C-terminus-interacting protein, RGS-GAIP-interacting protein, RGS19-interacting protein 1, RGS19IP1, synectin, tax interaction protein 2, or TIP-2), GIPC2, and GIPC3, which may act as scaffold proteins linking heterotrimeric G-proteins to seven-transmembrane-type WNT receptor or to receptor tyrosine kinases. They might play key roles in carcinogenesis and embryogenesis through modulation of growth factor signaling and cell adhesion. GIPCs are proteins with a GIPC homology 1 (GH1) domain, a central PDZ domain and a GH2 domain. This model corresponds to the GH2 domain, which mediates the interaction with myosin VI and is involved in homodimerization in the autoinhibited state.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 9055336  261 EEKAIEKVDDLLESYMGIRDTELAATMVELGKDKRNPDELAEALDERLGDFAFPDEFVFDVWGAI 325
Cdd:cd21180   1 EEKAIEKIDDLLESYMGIRDDELAQTIVELGKDKSNPDEFAEALDESLGDFAFPDEFVFDVWGAI 65

GIPC-homology 2 (GH2) domain found in the GIPC family; The GIPC family includes PDZ domain-containing proteins, GIPC1 (also called GAIP C-terminus-interacting protein, RGS-GAIP-interacting protein, RGS19-interacting protein 1, RGS19IP1, synectin, tax interaction protein 2, or TIP-2), GIPC2, and GIPC3, which may act as scaffold proteins linking heterotrimeric G-proteins to seven-transmembrane-type WNT receptor or to receptor tyrosine kinases. They might play key roles in carcinogenesis and embryogenesis through modulation of growth factor signaling and cell adhesion. GIPCs are proteins with a GIPC homology 1 (GH1) domain, a central PDZ domain and a GH2 domain. This model corresponds to the GH2 domain, which mediates the interaction with myosin VI and is involved in homodimerization in the autoinhibited state.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 9055336  261 EEKAIEKVDDLLESYMGIRDTELAATMVELGKDKRNPDELAEALDERLGDFAFPDEFVFDVWGAI 325
Cdd:cd21180   1 EEKAIEKIDDLLESYMGIRDDELAQTIVELGKDKSNPDEFAEALDESLGDFAFPDEFVFDVWGAI 65

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

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 9055336    143 LGLTI---TDNGAGYAFIKRIKEGSvIDHIQLISVGDMIEAINGQSLLGCRHYEVARLLKE 200
Cdd:pfam00595  12 LGFSLkggSDQGDPGIFVSEVLPGG-AAEAGGLKVGDRILSINGQDVENMTHEEAVLALKG 71

PDZ domain of GIPC family proteins; GIPC1/GIPC (GAIP/RGS19-interacting protein), GIPC2, and GIPC3 (also known as C19orf64) constitute the GIPC family. These proteins contain an N-terminal GIPC-homology 1 (GH1) domain, a central PDZ domain, and a C-terminal GH2 domain. GIPC proteins function as adaptor molecules that assemble RTKs, GPCRs, integrins, transmembrane proteins and cytoplasmic signaling regulators as cargoes of MYO6-dependent endocytic transport. Mutations in the Gipc1 and Gipc2 genes have been linked to cancer, while mutations in the Gipc3 gene cause nonsyndromic hearing loss. 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 GIPC 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 9055336  128 KGQRKEVEVFKSEEALGLTITDNGAGYAFIKRIKEGSVIDHIQLISVGDMIEAINGQSLLGCRHYEVARLLKELPRGRTF 207
Cdd:cd06707   1 KGQPKEIEVTKSEDALGLTITDNGAGYAFIKRIKEGSIMDKVPAICVGDHIEKINGESLVGCRHYEVARMLKEIPIGETF 80

                ....*....
gi 9055336  208 TLKLTEPRK 216
Cdd:cd06707  81 TLRLVEPKK 89

PDZ domain of PDZ domain-containing protein GIPC3, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of GIPC3, and related domains. GIPC3 (also known as C19orf64) belongs to the GIPC family, members of which contain an N-terminal GIPC-homology 1 (GH1) domain, a central PDZ domain, and a C-terminal GH2 domain. GIPC proteins function as adaptor molecules that assemble RTKs, GPCRs, integrins, transmembrane proteins and cytoplasmic signaling regulators as cargoes of MYO6-dependent endocytic transport. Mutations in the Gipc3 gene cause nonsyndromic hearing loss. 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 GIPC3 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 9055336  128 KGQRKEVEVFKSEEALGLTITDNGAGYAFIKRIKEGSVIDHIQLISVGDMIEAINGQSLLGCRHYEVARLLKELPRGRTF 207
Cdd:cd23079   1 RGETKEVEVTKTEDALGLTITDNGAGYAFIKRIKEGSIIDRIKAVCVGDHIEAINDQSIVGCRHYEVAKMLRELPKSQPF 80

                ....*....
gi 9055336  208 TLKLTEPRK 216
Cdd:cd23079  81 TLRLVEPKR 89

GIPC homology 2 (GH2) domain-like family; The GIPC (GAIP C-terminus-interacting protein) family of proteins mediate endocytosis by tethering cargo proteins to the motor myosin VI. This model represents the C-terminal GIPC homology 2 or GH2 domain (plus the linker to the PDZ domain located N-terminally of GH2), which mediates the interaction with myosin VI and is involved in homodimerization in the autoinhibited state. The family also includes DEAH box protein 8 (DHX8) and similar proteins. DHX8 (a human homolog of yeast Prp22), also called RNA helicase HRH1, is an ATP-dependent RNA helicase involved in pre-mRNA splicing as a component of the spliceosome. It facilitates nuclear export of spliced mRNA by releasing the RNA from the spliceosome. DHX8 contains a GH2-like domain at the N-terminus, which shows high sequence similarity with the GH2 domain found in GIPC proteins.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 9055336  262 EKAIEKVDDLLESYMGIRDTELAATMVELGKDKRNPDELAEALDErlGDFAFPDEFVFDVWGAI 325
Cdd:cd21690   1 LSAIEKVDDLLKNYLGIDDPELAEFVISLAKKKKNPDEFAEALDE--NDAAFPDEFVFDLYRAI 62

PDZ domain of connector enhancer of kinase suppressor of ras 1 (CNK1), CNK2, CNK3, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of CNK1 (also known as connector enhancer of KSR 1 (CNKSR1), CNK homolog protein 1, connector enhancer of KSR-like), CNK2 (also known as CNKSR2, CNK homolog protein 2), and CNK3 (also known as CNKSR3, CNK homolog protein 3, CNKSR family member 3, maguin-like). CNK proteins modulate Ras-mediated signaling, acting downstream of Ras as a scaffold for the Raf/MEK/ERK kinase cascade. They also modulate signaling mediated via Rho family small GTPases, through interactions with various guanine nucleotide exchange factors (GEFs) and GTPase activating proteins (GAPs), and modulate the insulin signaling pathway through interactions with the Arf guanine nucleotide exchange factors. CNK proteins also regulate cell proliferation and migration by acting as scaffolds for the PI3K/Akt and JNK signaling cascades. CNK2 plays a role in the molecular processes that govern morphology of the postsynaptic density (PSD), and influences subcellular localization of the regulatory NCK-interacting kinase TNIK. TNIK binds a region of CNK2 including the PDZ and the DUF domain; this region also binds the kinase MINK1. CNK2 may also influence the membrane localization of MINK1. CNK3 plays a part in transepithelial sodium transport; it coordinates assembly of an epithelial sodium channel (ENaC)-regulatory 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 CNK1-like family domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged as beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta- strand F.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 9055336  138 KSEEALGLTITDNGAGYAFIKRIKEGSVIDHIQLISVGDMIEAINGQSLLGCRHYEVARLLKELPRGRTFTLK 210
Cdd:cd06748   9 KPEEGLGLEIKSTYNGLHVITGTKENSPADRCGKIHAGDEVIQVNYQTVVGWQLKNLVRALREDPHGVTLTLK 81

PDZ domain 4 of membrane-associated guanylate kinase inverted 1 (MAGI-1), MAGI-2, and MAGI-3, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 4 of MAGI1, 2, 3 (MAGI is also known as Membrane-associated guanylate kinase, WW and PDZ domain-containing protein) and related domains. MAGI proteins have been implicated in the control of cell migration and invasion through altering the activity of phosphatase and tensin homolog (PTEN) and modulating Akt signaling. Four MAGI proteins have been identified (MAGI1-3 and MAGIX). MAGI1-3 have 6 PDZ domains and bind to the C-terminus of PTEN via their PDZ2 domain. MAGIX has a single PDZ domain that is related to MAGI1-3 PDZ domain 5. Other binding partners for MAGI1 include JAM4, C-terminal tail of high risk HPV-18 E6, megalin, TRAF6, Kir4.1 (basolateral K+ channel subunit), and cadherin 23; for MAGI2, include DASM1, dendrin, axin, beta- and delta-catenin, neuroligin, hyperpolarization-activated cation channels, beta1-adrenergic receptors, NMDA receptor, and TARPs; and for MAGI3 includes LPA2. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This MAGI family PDZ4 domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2); arranged as beta-strands A, -B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 9055336  127 VKGQRKEVEVFkseealGLTI--TDNGAGYAFIKRIKEGSVIDHIQLISVGDMIEAINGQSLLGCRHYEVARLLKElpRG 204
Cdd:cd06734   4 VTLTRRENEGF------GFVIisSVNKKSGSKIGRIIPGSPADRCGQLKVGDRILAVNGISILNLSHGDIVNLIKD--SG 75

                ....*...
gi 9055336  205 RTFTLKLT 212
Cdd:cd06734  76 LSVTLTIV 83

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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 9055336  133 EVEVFKSEEALGLTItdngAGYA-----------FIKRIKEGSVIDHIQLISVGDMIEAINGQSLLGCRHYEVARLLKEl 201
Cdd:cd06791   4 EVELVKDEQGLGITI----AGYVgekasgelsgiFVKSIIPGSAADQDGRIQVNDQIIAVDGVNLQGFTNQEAVEVLRN- 78

                        90
                ....*....|
gi 9055336  202 pRGRTFTLKL 211
Cdd:cd06791  79 -TGQVVHLTL 87

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

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 9055336  133 EVEVFKSEEALGLTITDNGAGyafiKRIKegSVIDHIQL--ISVGDMIEAINGQSLLGCRHYEVARLLKELPRGRTFTL 209
Cdd:cd06732   5 TVPIVKGPMGFGFTIADSPQG----QRVK--QILDPQRCrgLQEGDLIVEINGQNVQNLSHAQVVDVLKECPKGSEVTL 77

PDZ domain 3 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 PDZ3 domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 9055336  134 VEVFKSE-EALGLTITD---NGAGYAFIKRIKEGSVIDHIQLISVGDMIEAINGQSLLGCRHYEVARLLK 199
Cdd:cd06684   5 VEIEKTPgSSLGITLSTsthRNKQVIVIDSIKPASIADRCGALHVGDHILSIDGTSVEHCSLAEATQLLA 74

PDZ domain 1 of amyloid-beta A4 precursor protein-binding family A member 1 (APBA1), APBA2, APBA3, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 1 of APBA1, APBA2, APBA3, and related domains. The APBA/X11/Mint protein family includes three members: neuron specific APBA1 (also known as X11alpha and Mint1) and APBA2 (also known as X11beta and Mint2), and the ubiquitously expressed APBA3 (also known as (X12gamma and Mint3). They are involved in regulating neuronal signaling, trafficking and plasticity. They contain two PDZ domains (PDZ1 and PDZ2) which bind a variety of proteins: Arf GTPases (APBA1 and APBA2 PDZ2) and neurexin (APBA1 and APBA2 PDZ1 and 2), which are involved in vesicle docking and exocytosis; alpha1B subunit of N-type Ca2+ channel (APBA1 PDZ1) that is involved in ion channels; KIF17 (APBA1 PDZ1) that is involved in transport and traffic; and Alzheimer's disease related proteins such as APP (APBA3 PDZ2), CCS (APBA1 PDZ2), NF-kappa-B/p65 (APBA2 PDZ2), presenilin-1 (APBA1 and APBA2 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 APBA1,2,3-like family domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged as beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta- strand F.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 9055336  132 KEVEVFKSE-EALGLTITDNGAGY----AFIKRIKEGSVIDHIQLISVGDMIEAINGQSLLG 188
Cdd:cd06720   1 KEVVVEKQKgEILGVVIVESGWGSllptVVVANMMPGGPAARSGKLNIGDQIMSINGTSLVG 62

PDZ domain 3 of the full-length isoform of whirlin, PDZ domain 1 of the short isoform of whirlin, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 3 of the full-length isoform of whirlin, PDZ domain 1 of the short 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 PDZ3 domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 9055336  134 VEVFKSEEALGLTItDNGAGYAF----IKRIKEGSVIDHIQLISVGDMIEAINGQSLLGCRHYEVARLLKE 200
Cdd:cd06742   4 VRIKKTKPTLGIAI-EGGANTKQplprVINIQRGGSAHNCGGLKVGHVILEVNGTSLRGLEHREAARLIAE 73

PDZ domain 4 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 4 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 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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 9055336  133 EVEVFKSEEALGL----TITDNGAGYAFIKRIKEGSVIDHIQLISVGDMIEAINGQSLLGCRHYEVARLLKELP 202
Cdd:cd06668   6 QLSKFSESSGLGIslegTVDVEVRGHHYIRSILPEGPVGRNGKLFSGDELLEVNGIQLLGLSHKEVVSILKELP 79

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        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 9055336  132 KEVEVFKSEEALGLTITD-NGAGYA----FIKRIKEGSVIDHIQLISVGDMIEAINGQSLLGCRHYEVARLLKELP 202
Cdd:cd06758   3 WKMHLLKEKGGLGIQITGgKGSKRGdigiFVAGVEEGGSADRDGRLKKGDELLMINGQSLIGLSHQEAVAILRSSA 78

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        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 9055336  129 GQRKEVEVFKSEEALGLTIT--DN---GAGYAFIKRI-KEGSVIDHIQLISvGDMIEAINGQSLLGCRHYEVARLLKELP 202
Cdd:cd23058   3 GKKLHIQLKKGPEGLGFSITsrDNptgGSGPIYIKNIlPKGAAIQDGRLKA-GDRLLEVNGVDVTGKTQEEVVSLLRSTK 81

                ....*..
gi 9055336  203 RGRTFTL 209
Cdd:cd23058  82 LGGTVSL 88

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
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 9055336  134 VEVFK-SEEALGLTITdNGAGY------AFIKRIKEGSVIDHIQLISVGDMIEAINGQSLLGCRHYEVARLLK 199
Cdd:cd06675   3 VEIKRgPQDSLGISIA-GGVGSplgdvpVFIAMIQPNGVAAQTGKLKVGDRIVSINGQSTDGLTHSEAVNLLK 74

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        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 9055336  134 VEVFKSEEALGLTI----TDNGAgyaFIKRIKEGSVIDHIQLISVGDMIEAINGQSLLGCRHYEVARLLKElPRGrtfTL 209
Cdd:cd10817   2 VELPKDQGGLGIAIseedTENGI---VIKSLTEGGPAAKDGRLKVGDQILAVDDESVVGCPYEKAISLLKT-AKG---TV 74

                ...
gi 9055336  210 KLT 212
Cdd:cd10817  75 KLT 77

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        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 9055336  138 KSEEALGLTITDNGAGYA-------FIKRIKEGSVIDHIQLISVGDMIEAINGQSLLGCRHYEVARLLKELP 202
Cdd:cd06694   8 KKDPQKGLGFTIVGGENSgsldlgiFVKSIIPGGPADKDGRIKPGDRIIAINGQSLEGKTHHAAVEIIQNAP 79

PDZ domain of membrane palmitoylated protein 6 (MPP6), MPP2, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of MPP6, MPP2, and related domains. MPP6 (also known as MAGUK p55 subfamily member, Protein associated with Lin-7, 2 (PALS2), Veli-associated MAGUK 1, and VAM-1) is a membrane-associated guanylate kinase (MAGUK)-like protein. MPP6 is a regulator of Lin-7 expression and localization. MPP6 is also known to bind cell-adhesion protein, nectin-like molecule-2 (Necl-2), and localize to the basolateral plasma membrane in mammalian epithelial cells. MPP2 (also known as MAGUK p55 subfamily member 2) is a postsynaptic protein that links SynCAM1 cell adhesion molecules to core components of the postsynaptic density. Other members of this family include the Drosophila Vari protein, an essential basolateral septate junction protein which interacts with the cell-adhesion protein neurexin IV. 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 MPP6-MPP2-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 9055336  138 KSEEALGLTI-TDNGAGYafIKRIKEGSVIDHIQLISVGDMIEAINGQ 184
Cdd:cd10832   8 NPGEPLGVTVrLEEGELV--IARILHGGMIDRQGLLHVGDIIKEVNGV 53

PDZ domain of syntrophins, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of syntrophins (including alpha-1-syntrophin, beta-1-syntrophin, beta-2-syntrophin, gamma-1-syntrophin, and gamma-2-syntrophin), and related domains. Syntrophins play a role in recruiting various signaling molecules into signaling complexes and help provide appropriate spatiotemporal regulation of signaling pathways. They function in cytoskeletal organization and maintenance; as components of the dystrophin-glycoprotein complex (DGC), they help maintain structural integrity of skeletal muscle fibers. They link voltage-gated sodium channels to the actin cytoskeleton and the extracellular matrix, and control the localization and activity of the actin reorganizing proteins such as PI3K, PI(3,4)P2 and TAPP1. Through association with various cytoskeletal proteins within the cells, they are involved in processes such as regulation of focal adhesions, myogenesis, calcium homeostasis, and cell migration. They also have roles in synapse formation and in the organization of utrophin, acetylcholine receptor, and acetylcholinesterase at the neuromuscular synapse. 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 syntrophin-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 9055336  132 KEVEVFKSEEA-LGLTITdNGAGYAF---IKRIKEGSVIDHIQLISVGDMIEAINGQSLLGCRHYEVARLLK 199
Cdd:cd06801   1 RTVRVVKQDVGgLGISIK-GGAEHKMpilISKIFKGQAADQTGQLFVGDAILSVNGENLEDATHDEAVQALK 71

PDZ domain 3 of inactivation-no-after-potential D (INAD), and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 3 of INAD, and related domains. INAD assembles key enzymes of the Drosophila compound eye photo-transduction pathway into a supramolecular complex, supporting efficient and fast light signaling. It contains 5 PDZ domains arranged in tandem (PDZ1-PDZ5) which independently bind various proteins. INAD PDZ2 binds eye-specific protein kinase C, INAD PDZ3 binds transient receptor potential (TRP) channel, and INAD PDZ4,5 tandem binds NORPA (phospholipase Cbeta, PLCbeta). Mutations of the inaD gene that lead to disruption of each of these interactions impair fly photo signal transduction. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This INAD-like family PDZ3 domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*
gi 9055336  156 FIKRIKEGSVIDHIQLiSVGDMIEAINGQSLLGCRHYEVARLLKE 200
Cdd:cd23064  27 FISDLREGSNAELAGV-KVGDMLLAVNQDVTLESNYDDATGLLKR 70

PDZ domain of membrane palmitoylated protein1 (MPP1), and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of MPP1, and related domains. MPP1 (also known as MAGUK p55 subfamily member 1, erythrocyte membrane protein p55, EMP55) is a membrane-associated guanylate kinase (MAGUK)-like protein which forms a complex with protein 4.1 and glycophorin C (GPC) at the cytoplasmic face of the plasma membrane; this complex is essential for cytoskeleton-membrane linkage in erythrocytes and many non-erythroid cells, and participates in the determination of membrane stability and cell shape. MPP1, by interacting with various scaffold proteins and cytoskeletal proteins in the postsynaptic density, also plays an important role in organizing synaptic and non-synaptic structures. MPP1 is also a component of the Crumbs protein complex in the mammalian retina and may link the Usher protein network and the Crumbs protein complex. The MPP1 PDZ domain binding partners include GPC, ABCC4, and CADM1/Necl-2/SynCAM1. 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 MPP1-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 9055336  139 SEEALGLTITDNGAGYAFIKRIKEGSVIDHIQLISVGDMIEAINGQSLLGCRHYEVARLLKE 200
Cdd:cd10830   9 TEEPMGITLKLNEKQSCIVARILHGGMIHRQGSLHVGDEILEINGKSVTNHSVDQLQKMLKE 70

PDZ domain 2 of harmonin isoforms a, b, and c, and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 2 of harmonin isoforms a, b, and c, and related domains. Harmonin (also known as Usher Type 1C, PDZ-73 and AIE-75) is a key organizer of the Usher (USH) protein interactome. USH syndrome is the leading cause of hereditary sensory deaf-blindness in humans; three clinically distinct types of USH have been identified, type 1 to 3. The gene encoding harmonin (USH1C) is the causative gene for the USH type 1C phenotype. There are at least 10 alternatively spliced isoforms of harmonin, which are divided into three subclasses (a, b, and c). All isoforms contain the first two PDZ domains and the first coiled-coil domain. The a and b isoforms all have a third PDZ domain. The different PDZ domains are responsible for interactions with all known Usher syndrome type 1 proteins, and most Usher syndrome type 2 proteins. 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 harmonin 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 9055336  132 KEVEVFKSEEA---LGLTITdNGAGYA---FIKRIKEGSVIDHIQLiSVGDMIEAINGQSLLGCRHYEVARLLKElPRGR 205
Cdd:cd06738   1 KEKKVFISLVGtrgLGCSIS-SGPTQKpgiFISNVKPGSLAEEVGL-EVGDQIVEVNGTSFTNVDHKEAVMALKS-SRHL 77

                ....*
gi 9055336  206 TFTLK 210
Cdd:cd06738  78 TITVR 82

PDZ domain of protein Lin-7 and related domains; PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of Lin-7 (also known as LIN-7 or LIN7), and related domains. Lin-7 targets and organize protein complexes to epithelial and synaptic plasma membranes. There are three mammalian Lin-7 homologs: Lin-7A (protein lin-7 homolog A, also known as mammalian lin-seven protein 1 (MALS-1), vertebrate lin-7 homolog 1 (Veli-1), tax interaction protein 33); Lin-7B (also known as MALS-2, Veli-2); and Lin-7C (also known as MALS-3, Veli-3). Lin-7 is involved in localization of the Let-23 growth factor receptor to the basolateral membrane of epithelial cells, in tight junction localization of insulin receptor substrate p53 (IRSp53), in retaining gamma-aminobutyric (GABA) transporter (BGT-1) at the basolateral surface of epithelial cells, and in regulating recruitment of neurotransmitter receptors to the postsynaptic density (PSD). The Lin7 PDZ domain binds Let-23, BGT and beta-catenin, and NMDA (N-methyl-D-aspartate) receptor NR2B. Lin-7 also binds to the PDZ binding motif located in the C-terminal tail of Rhotekin, an effector protein for small GTPase Rho. PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This Lin-7-like family domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged in the order: beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta-strand F.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 9055336  134 VEVFKSEEALGLTITDNGAGYA--FIKRIKEGSVIDHIQLISVGDMIEAINGQSLLGCRHYEVARLLK 199
Cdd:cd06796   5 VELPKTEEGLGFNVMGGKEQNSpiYISRIIPGGVADRHGGLKRGDQLLSVNGVSVEGEHHEKAVELLK 72