PDZ domain 1 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 1 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 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.
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:1IHJ: PDZ domain 1 of Drosophila melanogaster InaD binds NorpA (phospholipase C) C-terminal peptide (GKTEFCA); contacts at 4A