Differential requirement for ATG2A domains for localization to autophagic membranes and lipid droplets.

ATG2 is one of the autophagy-related (ATG) proteins essential for autophagosome formation and localizes to isolation membranes and lipid droplets in mammalian cells. Here, we investigated the requirement of regions in ATG2A for its organellar localization and function. The N-terminal amino acids 1-198 and the C-terminal amino acids 1830-1938 are required for the localization to isolation membranes and lipid droplets, respectively. The C-terminal region is not required for the localization to isolation membranes and for autophagy. We also identified an amphipathic helix in ATG2A that is required for both its localization to organelles and autophagosome formation. These data suggest that the dual localization of ATG2A is regulated by different regions.