PDZ domain of partitioning defective 6 (Par6), Drosophila Rho GTPase-activating protein 100F (RhoGAP100F), and related domains
PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of Par6 (also known as PAR6 or Par-6), RhoGAP100F, and related domains. Par6 is part of a conserved machinery that directs metazoan cell polarity, a process necessary for the function of diverse cell types. Par6 forms a cell polarity-regulatory complex with atypical protein kinase C (aPKC) and Par3. Par6 can also directly associate with PALS1 (proteins associated with Lin7, also known as Stardust) providing a link between the Par3/aPKC/Par6 complex and the PALS1-PATJ (protein-associated TJ) complex. Binding partners of the Par6-PDZ domain include Par3, PALS1/Stardust; leucine-rich repeat-containing protein netrin-G ligand-2 (NGL-2), human crumbs (CRB3) involve in the morphogenesis of the tight junctions in mammalian epithelial cells, and PAR-6 co-operates with the Par6 semi-CRIB domain to bind CDC42. CDC42 regulates the Par6 PDZ domain through an allosteric CRIB-PDZ transition. Drosophila RhoGAP100F, also known as synapse defective protein 1 homolog (syd-1 homolog), is a GTPase activator for the Rho-type GTPases by converting them to an inactive GDP-bound form. The RhoGAP100F-PDZ domain binds the neurexin C terminus to control synapse formation at the Drosophila neuromuscular junction. 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 Par6-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.
Feature 1:peptide binding site [polypeptide binding site]
Evidence:
Comment:based on canonical PDZ domains with structure
Structure:1X8S: PDZ domain of Drosophila melanogaster PAR-6 bound to an internal sequence from protein PALS1/Stardust; contacts at 4A
Comment:PDZ domains specifically recognize and bind to short C-terminal peptide motifs, but can also recognize internal peptide motifs and certain lipids