Signal recognition particle receptor-β (SR-β) coordinates cotranslational N-glycosylation

Sci Adv. 2023 Mar 17;9(11):eade8079. doi: 10.1126/sciadv.ade8079. Epub 2023 Mar 15.

Abstract

Proteins destined for the secretory compartment of the cell are cotranslationally translocated into the endoplasmic reticulum. The majority of these proteins are N-glycosylated, a co- and posttranslational modification that ensures proper protein folding, stability, solubility, and cellular localization. Here, we show that the [Formula: see text] subunit of the signal recognition particle receptor (SR) is required for assembly of the N-glycosylation-competent translocon. We report that guanine analog chemical probes identified by high-throughput screening or mutation of the SR-[Formula: see text] guanosine triphosphate binding site cause an N-glycosylation-deficient phenotype. Neither method alters the association of SR-[Formula: see text] with SR-[Formula: see text], but both approaches reduce the association of SR-[Formula: see text] with the oligosaccharyltransferase complex. These experiments demonstrate that SR-[Formula: see text] has a previously unrecognized function coordinating endoplasmic reticulum translation with N-glycosylation.

MeSH terms

  • Endoplasmic Reticulum* / metabolism
  • Glycosylation
  • Receptors, Cytoplasmic and Nuclear* / metabolism
  • Receptors, Peptide / metabolism

Substances

  • signal peptide receptor
  • Receptors, Cytoplasmic and Nuclear
  • Receptors, Peptide