Reference - PMID:30911189 - Atg2 mediates direct lipid transfer between membranes for autophagosome formation.
Reference summary
- PubMed ID
- PMID:30911189
- Title
- Atg2 mediates direct lipid transfer between membranes for autophagosome formation.
- Authors
- Osawa T, Kotani T, Kawaoka T, Hirata E, Suzuki K, Nakatogawa H, Ohsumi Y, Noda NN
- Citation
- Nat Struct Mol Biol 2019 Apr;26(4):281-288
- Publication year
- 2019
- Abstract
- A key event in autophagy is autophagosome formation, whereby the newly synthesized isolation membrane (IM) expands to form a complete autophagosome using endomembrane-derived lipids. Atg2 physically links the edge of the expanding IM with the endoplasmic reticulum (ER), a role that is essential for autophagosome formation. However, the molecular function of Atg2 during ER-IM contact remains unclear, as does the mechanism of lipid delivery to the IM. Here we show that the conserved amino-terminal region of Schizosaccharomyces pombe Atg2 includes a lipid-transfer-protein-like hydrophobic cavity that accommodates phospholipid acyl chains. Atg2 bridges highly curved liposomes, thereby facilitating efficient phospholipid transfer in vitro, a function that is inhibited by mutations that impair autophagosome formation in vivo. These results suggest that Atg2 acts as a lipid-transfer protein that supplies phospholipids for autophagosome formation.
