Oligosaccharyltransferase Is Involved in Targeting to ER-Associated Degradation.

ABSTRACT: Most membrane and secretory proteins undergo N-glycosylation, catalyzed by oligosaccharyltransferase (OST), a membrane-bound complex in the endoplasmic reticulum (ER). Proteins failing quality control are degraded via ER-associated degradation (ERAD), involving retrotranslocation to cytosolic proteasomes, or relegated to ER subdomains and eliminated via ER-phagy. Using stable isotope labeling by amino acids in cell culture (SILAC) proteomics, we identified OST subunits as differential key interactors with a misfolded ER protein bait upon proteasomal inhibition, suggesting unexpected involvement in ERAD. Previous reports implied additional roles for OST subunits beyond N-glycosylation, such as quality control by ribophorin I. We tested OST engagement in glycoprotein and non-glycosylated pro

SUBMITTER: Shenkman M 

PROVIDER: S-EPMC12564220 | biostudies-literature | 2025 Oct

REPOSITORIES: biostudies-literature