PDZ domain 1 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 1 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 PDZ1 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.
Feature 1:peptide binding site [polypeptide binding site]
Evidence:
Comment:based on canonical PDZ domains with structure
Comment:PDZ domains specifically recognize and bind to short C-terminal peptide motifs, but can also recognize internal peptide motifs and certain lipids
Structure:5N7D: PDZ domain 1 of human MAGI-1 binds C-terminal peptide of ribosomal S6 kinase 1 (RSK 1), contacts at 4A
Structure:2I04: Mus musculus MAGI-1 PDZ1 homodimer binds C-terminal peptide of human papillomavirus (HPV) E6, contacts at 4A
Comment:each E6 peptide binds to the substrate groove of one PDZ1; in addition, E6 peptide also interacts directly with Asp of the other PDZ1 monomer as well as indirectly via water molecules
Comment:PDZ1 homodimer may have functional relevance for MAGI-1 activity
Jiyao W et al.(2023). "The conserved domain database in 2023.",