Schematic model of the steps involved in autophagy. Under starvation conditions a signal transduction event results in the inactivation of Tor kinase and the induction of autophagy. Membrane from an unknown source nonspecifically sequesters cytoplasm. The resulting doublemembrane autophagosome targets to and fuses with the lysosome/vacuole. Fusion allows the release of the single-membrane autophagic body that is subsequently degraded in the lysosome/vacuole lumen allowing the recycling of cytoplasmic constituents.