7D0I

Cryo-EM structure of Schizosaccharomyces pombe Atg9

7D0I の概要

• エントリーDOI: 10.2210/pdb7d0i/pdb
• EMDBエントリー: 30535
• 分子名称: Autophagy-related protein 9, Lauryl Maltose Neopentyl Glycol (2 entities in total)
• 機能のキーワード: autophagy, membrane protein, unknown function
• 由来する生物種: Schizosaccharomyces pombe (strain 972 / ATCC 24843) (Fission yeast)
• タンパク質・核酸の鎖数: 6
• 化学式量合計: 508515.29

構造登録者

Matoba, K.,Tsutsumi, A.,Kikkawa, M.,Noda, N.N. (登録日: 2020-09-10, 公開日: 2020-10-28, 最終更新日: 2024-03-27)

主引用文献

Matoba, K.,Kotani, T.,Tsutsumi, A.,Tsuji, T.,Mori, T.,Noshiro, D.,Sugita, Y.,Nomura, N.,Iwata, S.,Ohsumi, Y.,Fujimoto, T.,Nakatogawa, H.,Kikkawa, M.,Noda, N.N.
Atg9 is a lipid scramblase that mediates autophagosomal membrane expansion.
Nat.Struct.Mol.Biol., 27:1185-1193, 2020

PubMed Abstract: The molecular function of Atg9, the sole transmembrane protein in the autophagosome-forming machinery, remains unknown. Atg9 colocalizes with Atg2 at the expanding edge of the isolation membrane (IM), where Atg2 receives phospholipids from the endoplasmic reticulum (ER). Here we report that yeast and human Atg9 are lipid scramblases that translocate phospholipids between outer and inner leaflets of liposomes in vitro. Cryo-EM of fission yeast Atg9 reveals a homotrimer, with two connected pores forming a path between the two membrane leaflets: one pore, located at a protomer, opens laterally to the cytoplasmic leaflet; the other, at the trimer center, traverses the membrane vertically. Mutation of residues lining the pores impaired IM expansion and autophagy activity in yeast and abolished Atg9's ability to transport phospholipids between liposome leaflets. These results suggest that phospholipids delivered by Atg2 are translocated from the cytoplasmic to the luminal leaflet by Atg9, thereby driving autophagosomal membrane expansion.

PubMed: 33106658
DOI: 10.1038/s41594-020-00518-w

実験手法

ELECTRON MICROSCOPY (3 Å)