PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain of densin, erbin, and related domains. Densin (also known as leucine-rich repeat-containing protein 7, LRRC7, densin-180, protein LAP1) and erbin (also known as densin-180-like protein, Erbb2-interacting protein, protein LAP2) belong to the LAP (leucine-rich repeat and PDZ domain) family of scaffolding proteins that play roles in the maintenance of cell shape and apical-basal polarity. Densin and erbin are components of the excitatory postsynaptic compartment and are regulators of dendritic morphology and postsynaptic structure. The densin PDZ domain binds CaV1.3 alpha1 subunit, delta-catenin, and MAGUIN-1. Binding partners of the erbin PDZ domain include ErbB receptor tyrosine kinase ErbB2, HTLV-1 Tax1, Cav1.3 Ca2+channels, and constituents of the cadherin:catenin cell adhesion complex, in particular delta-catenin, p0071 and ARVCF. The erbin PDZ domain binds Smad3, a transductor of the TGFbeta pathway, possibly by a novel interface of binding. Erbin and two other LAP proteins (scribble and lano) redundantly regulate epithelial polarity and apical adhesion 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 densin and erbin-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.
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:1MFG: PDZ domain of human Erbin binds receptor tyrosine kinase ErbB2 C-terminal peptide (EYLGLDVPV); contacts at 4A
Jiyao W et al.(2023). "The conserved domain database in 2023.",