6GNI

Cryo-tomography and subtomogram averaging of Sar1-Sec23-Sec24 - fitted model.

6GNI の概要

• エントリーDOI: 10.2210/pdb6gni/pdb
• EMDBエントリー: 0044
• 分子名称: Protein transport protein SEC23, Protein transport protein SEC24, Small COPII coat GTPase SAR1, ... (6 entities in total)
• 機能のキーワード: copii coat, membrane trafficking, protein transport
• 由来する生物種: Saccharomyces cerevisiae (strain ATCC 204508 / S288c) (Baker's yeast); 詳細
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 194096.74

構造登録者

Hutchings, J.,Zanetti, G. (登録日: 2018-05-30, 公開日: 2018-10-17, 最終更新日: 2024-05-15)

主引用文献

Hutchings, J.,Stancheva, V.,Miller, E.A.,Zanetti, G.
Subtomogram averaging of COPII assemblies reveals how coat organization dictates membrane shape.
Nat Commun, 9:4154-4154, 2018

PubMed Abstract: Eukaryotic cells employ membrane-bound carriers to transport cargo between compartments in a process essential to cell functionality. Carriers are generated by coat complexes that couple cargo capture to membrane deformation. The COPII coat mediates export from the endoplasmic reticulum by assembling in inner and outer layers, yielding carriers of variable shape and size that allow secretion of thousands of diverse cargo. Despite detailed understanding of COPII subunits, the molecular mechanisms of coat assembly and membrane deformation are unclear. Here we present a 4.9 Å cryo-tomography subtomogram averaging structure of in vitro-reconstituted membrane-bound inner coat. We show that the outer coat (Sec13-Sec31) bridges inner coat subunits (Sar1-Sec23-Sec24), promoting their assembly into a tight lattice. We directly visualize the membrane-embedded Sar1 amphipathic helix, revealing that lattice formation induces parallel helix insertions, yielding tubular curvature. We propose that regulators like the procollagen receptor TANGO1 modulate this mechanism to determine vesicle shape and size.

PubMed: 30297805
DOI: 10.1038/s41467-018-06577-4

実験手法

ELECTRON MICROSCOPY (4.9 Å)