PDZ domain of regulator of G-protein signaling 3 (RGS3), and related domains
PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of RGS3, and related domains. RGS3 down-regulates GPCR signal transduction by increasing the GTPase activity of G-protein alpha subunits, thereby driving G-proteins into their inactive GDP-bound form. It downregulates G-protein-mediated release of inositol phosphates and activation of MAP kinases. In Eph/ephrin signaling, RGS3 binds via its PDZ domain to the cytoplasmic C terminus of Eph receptor tyrosine kinase EphB. 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 RGS3-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
Comment:PDZ domains specifically recognize and bind to short C-terminal peptide motifs, but can also recognize internal peptide motifs and certain lipids
Jiyao W et al.(2023). "The conserved domain database in 2023.",