6S7O

Cryo-EM structure of human oligosaccharyltransferase complex OST-A

6S7O の概要

• エントリーDOI: 10.2210/pdb6s7o/pdb
• EMDBエントリー: 10110
• 分子名称: Dolichyl-diphosphooligosaccharide--protein glycosyltransferase subunit STT3A, alpha-D-mannopyranose-(1-2)-alpha-D-mannopyranose-(1-2)-alpha-D-mannopyranose-(1-3)-[alpha-D-mannopyranose-(1-6)-alpha-D-mannopyranose-(1-6)]beta-D-mannopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose, alpha-D-mannopyranose-(1-2)-alpha-D-mannopyranose-(1-3)-[alpha-D-mannopyranose-(1-3)-[alpha-D-mannopyranose-(1-6)]alpha-D-mannopyranose-(1-6)]beta-D-mannopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose, ... (15 entities in total)
• 機能のキーワード: n-glycosylation, oligosaccharyltransferase, osta, transferase
• 由来する生物種: Homo sapiens (Human); 詳細
• タンパク質・核酸の鎖数: 8
• 化学式量合計: 325886.44

構造登録者

Ramirez, A.S.,Kowal, J.,Locher, K.P. (登録日: 2019-07-05, 公開日: 2019-12-18, 最終更新日: 2024-11-06)

主引用文献

Ramirez, A.S.,Kowal, J.,Locher, K.P.
Cryo-electron microscopy structures of human oligosaccharyltransferase complexes OST-A and OST-B.
Science, 366:1372-1375, 2019

PubMed Abstract: Oligosaccharyltransferase (OST) catalyzes the transfer of a high-mannose glycan onto secretory proteins in the endoplasmic reticulum. Mammals express two distinct OST complexes that act in a cotranslational (OST-A) or posttranslocational (OST-B) manner. Here, we present high-resolution cryo-electron microscopy structures of human OST-A and OST-B. Although they have similar overall architectures, structural differences in the catalytic subunits STT3A and STT3B facilitate contacts to distinct OST subunits, DC2 in OST-A and MAGT1 in OST-B. In OST-A, interactions with TMEM258 and STT3A allow ribophorin-I to form a four-helix bundle that can bind to a translating ribosome, whereas the equivalent region is disordered in OST-B. We observed an acceptor peptide and dolichylphosphate bound to STT3B, but only dolichylphosphate in STT3A, suggesting distinct affinities of the two OST complexes for protein substrates.

PubMed: 31831667
DOI: 10.1126/science.aaz3505

実験手法

ELECTRON MICROSCOPY (3.5 Å)