PP2A promotes ESCRT-0 complex formation on vacuolar membranes and microautophagy induction after TORC1 inactivation

Abstract Deformation of vacuolar membranes mediated by endosomal sorting complex required for transport (ESCRT) is necessary for microautophagy. Target of rapamycin complex 1 (TORC1) protein kinase negatively regulates ESCRT-0 (Vps27–Hse1) recruitment onto vacuolar membranes and microautophagy induction. However, whether and how protein phosphatase regulates these events is unknown. Here, we show that the TORC1-downstream protein phosphatase PP2A–Cdc55 is important for these events after TORC1 inactivation in budding yeast. Loss of PP2A–Cdc55 compromised vacuolar localization of Hse1, but not Vps27. This study revealed that the orchestrated action of PP2A induces microautophagy upon TORC1 inactivation.