ER membrane receptors engage core autophagy machinery to initiate ER-phagy
Abstract
Endoplasmic reticulum (ER) phagy is the form of selective autophagy that governs ER abundance and integrity by targeting dysfunctional ER fragments for degradation. How the recognition of ER fragments as autophagy substrates is coupled to engagement of the core autophagic machinery is largely unknown. Here, using a combination of in vitro reconstitution systems, structural modeling, and cell biology, we demonstrate that ER membrane receptors directly engage the core autophagy component ATG9A, as well as the PI3P-binding protein WIPI2, to initiate ER-associated autophagosome biogenesis. ER-phagy receptor–ATG9A association nucleates the recruitment of the other key autophagy proteins required to initiate ER-phagy. In parallel, ER-phagy receptor–WIPI2 engagement promotes rapid LC3 lipidation for autophagic membrane expansion. These data show how ER-phagy receptors trigger the cascade of events leading to ER autophagosome formation.
Article Details
Journal Info
Proceedings of the National Academy of Sciences
National Academy of Sciences
Authors (9)
Cha Wu
State Key Laboratory of Genetics and Development of Complex Phenotypes, Shanghai Key Laboratory of Metabolic Remodeling and Health, Institute of Metabolism and Integrative Biology, Fudan University
Haixia Yang
Shanghai Key Laboratory of Metabolic Remodeling and Health, State Key Laboratory of Genetics and Development of Complex Phenotypes, Institute of Metabolism and Integrative Biology, School of Life Sciences, Department of Endocrinology and Metabolism, Zhongshan Hospital, Fudan University
Chen Wang
Peiqi Huang
State Key Laboratory of Genetics and Development of Complex Phenotypes, Shanghai Key Laboratory of Metabolic Remodeling and Health, Institute of Metabolism and Integrative Biology, Fudan University
Ning Yan
Department of Chemical and Biomolecular Engineering
Ruobing Ren
Shanghai Key Laboratory of Metabolic Remodeling and Health, Institute of Metabolism and Integrative Biology, Shanghai Xuhui Central Hospital, Zhongshan-Xuhui Hospital, Fudan University
Wei Liu
Yi Lu
Chunmei Chang
Shanghai Key Laboratory of Metabolic Remodeling and Health, State Key Laboratory of Genetics and Development of Complex Phenotypes, Institute of Metabolism and Integrative Biology, School of Life Sciences, Department of Endocrinology and Metabolism, Zhongshan Hospital, Fudan University