Disulfide-crosslink analysis of the ubiquitin ligase Hrd1 complex during endoplasmic reticulum-associated protein degradation.

ABSTRACT: Misfolded proteins in the lumen of the endoplasmic reticulum (ER) are retrotranslocated into the cytosol and degraded by the ubiquitin-proteasome system, a pathway termed luminal ER-associated protein degradation. Retrotranslocation is mediated by a conserved protein complex, consisting of the ubiquitin ligase Hrd1 and four associated proteins (Der1, Usa1, Hrd3, and Yos9). Photocrosslinking experiments provided preliminary evidence for the polypeptide path through the membrane but did not reveal specific interactions between amino acids in the substrate and Hrd1 complex. Here, we have used site-specific disulfide crosslinking to map the interactions of a glycosylated model substrate with the Hrd1 complex in live S. cerevisiae cells. Together with available electron cryo-microscopy structur

SUBMITTER: Pisa R 

PROVIDER: S-EPMC9478403 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature