Specific interaction of ERp57 and calnexin determined by NMR spectroscopy and an ER two-hybrid system.

ABSTRACT: Calnexin and ERp57 act cooperatively to ensure a proper folding of proteins in the endoplasmic reticulum (ER). Calnexin contains two domains: a lectin domain and an extended arm termed the P-domain. ERp57 is a protein disulfide isomerase composed of four thioredoxin-like repeats and a short basic C-terminal tail. Here we show direct interactions between the tip of the calnexin P-domain and the ERp57 basic C-terminus by using NMR and a novel membrane yeast two-hybrid system (MYTHS) for mapping protein interactions of ER proteins. Our results prove that a small peptide derived from the P-domain is active in binding ERp57, and we determine the structure of the bound conformation of the P-domain peptide. The experimental strategy of using the MYTHS two-hybrid system to map interaction sites be

SUBMITTER: Pollock S 

PROVIDER: S-EPMC380975 | biostudies-literature | 2004 Mar

REPOSITORIES: biostudies-literature