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Updated: Aug 6, 2025

Analysis of SCAP N-glycosylation and Trafficking in Human Cells
Published on: November 8, 2016
Signal recognition particle receptor-β (SR-β) coordinates cotranslational N-glycosylation
Chatchai Phoomak1,2, Natalie Rinis1, Marta Baro1
1Department of Therapeutic Radiology, Yale School of Medicine, New Haven, CT 06511, USA.
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.
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