New insights into the essentiality of core autophagy factors revealed by comprehensive analysis

Autophagy is a conserved degradation process delivering intracellular components to lysosomes or vacuoles. Yeast studies have been pivotal in identifying autophagy-related genes (ATG) and defining the core machinery essential for autophagosome formation. A recent comprehensive analysis that systematically examined all atg mutants in Saccharomyces cerevisiae under autophagy-inducing conditions revealed that mutants lacking Atg13, Atg8-conjugation or Atg12-conjugation components retain partial activity in certain autophagy-related pathways, indicating that these core factors are not strictly essential for autophagy in yeast. In this commentary, we summarize how recent findings reshape our understanding of the flexibility in the essentiality of core autophagy factors and discuss the emerging importance of protein interaction-driven feedback in autophagy regulation.