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Updated: Feb 24, 2026

Exploring the Regulation of Lipid Droplet Catabolism through Lipophagy
Published on: January 31, 2025
The ULK complex initiates autophagosome formation at phosphatidylinositol synthase-enriched ER subdomains
Taki Nishimura1, Noboru Mizushima1
1a Department of Biochemistry and Molecular Biology, Graduate School and Faculty of Medicine , The University of Tokyo , Tokyo , Japan.
Abstract:
In our recent paper, we biochemically analyzed autophagosome-related membranes at the initiation stage of macroautophagy/autophagy using atg knockout (KO) cells and demonstrated that the ULK complex is recruited to 2 distinct membranes: the ER membrane and ATG9A-positive autophagosome precursors. We have also identified phosphatidylinositol synthase (PIS)-enriched ER subdomains as the initiation site of autophagosome formation. Based on these findings, we propose that the ULK complex, the PIS-enriched ER subdomain, and ATG9A vesicles together initiate autophagosome formation.
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