For more than 40 years, autophagy has been almost exclusively studied as a cellular response that allows adaptation to starvation situations. In nutrient-deprived conditions, cytoplasmic components and organelles are randomly sequestered into double-membrane vesicles called autophagosomes, creating the notion that this pathway is a nonselective process (reviewed in refs 1 and 2). Recent results, however, have demonstrated that under certain circumstances, cargoes such as protein complexes, organelles and bacteria can be selectively and exclusively incorporated into double-membrane vesicles. We have recently shown that actin plays an essential role in two selective types of autophagy in the yeast Saccharomyces cerevisiae, the cytoplasm to vacuole targeting (Cvt) pathway and pexophagy, raising the possibility that the structures formed by polymers of this protein helps autophagosomes in recognizing the cargoes that must be delivered to the vacuole. In this addendum, we discuss the possible central role of Atg11 as a molecule connecting cargoes, actin and pre-autophagosomal structure (PAS) elements.
- Cytoplasm to vacuole targeting