6Y4L

Crystal structure of human ER membrane protein complex subunits EMC2 and EMC9

6Y4L の概要

• エントリーDOI: 10.2210/pdb6y4l/pdb
• 分子名称: ER membrane protein complex subunit 2, ER membrane protein complex subunit 9, SULFATE ION, ... (7 entities in total)
• 機能のキーワード: complex, insertase, protein transport
• 由来する生物種: Homo sapiens (Human); 詳細
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 57281.01

構造登録者

Hegde, R.S.,O'Donnell, J.P. (登録日: 2020-02-21, 公開日: 2020-05-27, 最終更新日: 2024-05-15)

主引用文献

O'Donnell, J.P.,Phillips, B.P.,Yagita, Y.,Juszkiewicz, S.,Wagner, A.,Malinverni, D.,Keenan, R.J.,Miller, E.A.,Hegde, R.S.
The architecture of EMC reveals a path for membrane protein insertion.
Elife, 9:-, 2020

PubMed Abstract: Approximately 25% of eukaryotic genes code for integral membrane proteins that are assembled at the endoplasmic reticulum. An abundant and widely conserved multi-protein complex termed EMC has been implicated in membrane protein biogenesis, but its mechanism of action is poorly understood. Here, we define the composition and architecture of human EMC using biochemical assays, crystallography of individual subunits, site-specific photocrosslinking, and cryo-EM reconstruction. Our results suggest that EMC's cytosolic domain contains a large, moderately hydrophobic vestibule that can bind a substrate's transmembrane domain (TMD). The cytosolic vestibule leads into a lumenally-sealed, lipid-exposed intramembrane groove large enough to accommodate a single substrate TMD. A gap between the cytosolic vestibule and intramembrane groove provides a potential path for substrate egress from EMC. These findings suggest how EMC facilitates energy-independent membrane insertion of TMDs, explain why only short lumenal domains are translocated by EMC, and constrain models of EMC's proposed chaperone function.

PubMed: 32459176
DOI: 10.7554/eLife.57887

実験手法

X-RAY DIFFRACTION (2.2 Å)