+Search query
-Structure paper
Title | The atomic structure of a eukaryotic oligosaccharyltransferase complex. |
---|---|
Journal, issue, pages | Nature, Vol. 555, Issue 7696, Page 328-333, Year 2018 |
Publish date | Mar 15, 2018 |
Authors | Lin Bai / Tong Wang / Gongpu Zhao / Amanda Kovach / Huilin Li / |
PubMed Abstract | N-glycosylation is a ubiquitous modification of eukaryotic secretory and membrane-bound proteins; about 90% of glycoproteins are N-glycosylated. The reaction is catalysed by an eight-protein ...N-glycosylation is a ubiquitous modification of eukaryotic secretory and membrane-bound proteins; about 90% of glycoproteins are N-glycosylated. The reaction is catalysed by an eight-protein oligosaccharyltransferase (OST) complex that is embedded in the endoplasmic reticulum membrane. Our understanding of eukaryotic protein N-glycosylation has been limited owing to the lack of high-resolution structures. Here we report a 3.5 Å resolution cryo-electron microscopy structure of the Saccharomyces cerevisiae OST complex, revealing the structures of subunits Ost1-Ost5, Stt3, Wbp1 and Swp1. We found that seven phospholipids mediate many of the inter-subunit interactions, and an Stt3 N-glycan mediates interactions with Wbp1 and Swp1 in the lumen. Ost3 was found to mediate the OST-Sec61 translocon interface, funnelling the acceptor peptide towards the OST catalytic site as the nascent peptide emerges from the translocon. The structure provides insights into co-translational protein N-glycosylation, and may facilitate the development of small-molecule inhibitors that target this process. |
External links | Nature / PubMed:29466327 / PubMed Central |
Methods | EM (single particle) |
Resolution | 3.5 Å |
Structure data | |
Chemicals | ChemComp-EGY: ChemComp-NAG: |
Source |
|
Keywords | TRANSFERASE / complex / glycosylation |