Autophagy is an evolutionarily conserved process that is important for the degradation and recycling of cytoplasmic components. Upon starvation, non-selective bulk autophagy provides nutrients and amino acids, and so ensures cellular homeostasis. The first step in autophagy is the formation of phagophore assembly sites (PASs), the precursors of autophagosomes; this involves the recruitment and clustering of several autophagy-related (Atg) proteins. In yeast, the PAS forms close to the vacuole, but the relevance of this localisation and the underlying mechanisms are unknown. Therefore, David Hollenstein, Claudine Kraft and colleagues (Hollenstein et al., 2019) investigate here in more detail the link between the PAS and vacuole. They focus on the vacuolar membrane protein Vac8, which had previously been implicated in autophagy, although its role and function remained unknown. They now show that Vac8 constitutes a vacuolar tether that, through an interaction with the C-terminus of Atg13 at the PAS, stably anchors the PAS to the vacuole. This tether persists throughout autophagosome biogenesis, as yeast lacking Vac8 form fewer and smaller autophagosomes, often away from the vacuole, as well as exhibit inefficient fusion of their autophagosomes with the vacuole. Based on their findings, the authors propose a function for Vac8 in spatially confining autophagosome formation to the vicinity of the vacuole, which helps to coordinate autophagosome formation with vacuole fusion, thereby ensuring efficient bulk autophagy
