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Remodeling of vacuolar membranes mediated by endosomal sorting complex required for transport (ESCRT) is critical for microautophagy induction in budding yeast. Nutrient depletion and inactivation of target of rapamycin complex 1 (TORC1) protein kinase elicit recruitment of the ESCRT-0 complex (Vps27–Hse1) onto vacuolar membranes and ESCRT-mediated microautophagy induction. Mitotic protein phosphatase Cdc14 antagonizes TORC1-mediated phosphorylation in macroautophagy induction after nutrient starvation and TORC1 inactivation. Here, we report that Cdc14 downregulates microautophagy induction after TORC1 inactivation. Cdc14 dysfunction stimulated the vacuolar membrane recruitment of Hse1, but not Vps27, after TORC1 inactivation, promoting ESCRT-0 complex formation. Conversely, overexpression of CDC14 compromises Hse1 recruitment on vacuolar membranes and microautophagy induction after TORC1 inactivation. Thus, Cdc14 phosphatase regulates the fluxes of two types of autophagy in the opposite directions, namely, it elicits macroautophagy and attenuates microautophagy. • Cdc14 dysfunction facilitates microautophagy induction after TORC1 inactivation. • Cdc14 dysfunction elicits the vacuolar membrane recruitment of Hse1, but not Vps27. • Overexpression of CDC14 compromises ESCRT-mediated microautophagy induction. • Cdc14 upregulates macroautophagy and downregulates microautophagy. [ABSTRACT FROM AUTHOR]

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. • PP2A–Cdc55 promotes microautophagy induction after TORC1 inactivation. • PP2A–Cdc55 promotes vacuolar localization of Hse1 after TORC1 inactivation. • PP2A–Cdc55 promotes ESCRT-0 complex formation on vacuolar membranes. [ABSTRACT FROM AUTHOR]

Microautophagy is promoted after nutrient starvation and inactivation of target of rapamycin complex 1 (TORC1) kinase. Invagination of vacuolar membranes by endosomal sorting complex required for transport (ESCRT) is required for microautophagy. Vps27, a subunit of ESCRT-0, is recruited onto vacuolar membranes via dephosphorylation after TORC1 inactivation. Here, we showed that Hse1, another ESCRT-0 subunit, is also recruited onto vacuolar membranes after TORC1 inactivation, promoting formation of ESCRT-0 complex on vacuolar membranes. Hse1 recruitment was dependent on Vps27, whereas Vps27 recruitment was independent of Hse1. Not only Vps27 but also Hse1 was required for ESCRT-III recruitment onto vacuolar membranes and microautophagy induction after TORC1 inactivation. This study revealed that ESCRT-0 (Vps27–Hse1) complex formation on vacuolar membranes is important for microautophagy inactivation after TORC1 inactivation. • TORC1 inactivation promotes ESCRT-0 complex formation on vacuolar membranes. • Hse1 recruitment onto vacuolar membranes is dependent on Vps27, but not vise versa. • Both Vps27 and Hse1 are required for TORC1 inactivation-induced microautophagy. [ABSTRACT FROM AUTHOR]