Autophagosome closure by ESCRT: Vps21/RAB5-regulated ESCRT recruitment via an Atg17-Snf7 interaction.

The macroautophagy/autophagy pathway includes successive steps of phagophore assembly structure formation, phagophore expansion, autophagosome (AP) closure and AP fusion with the lysosome/vacuole. Although information about regulators, factors and molecular mechanisms important for early and late steps of autophagy is abundant, information about AP closure is scarce. In 2017, we reported that the Vps21/RAB5 GTPase module regulates AP closure in yeast. In a recent paper, we show that Vps21 regulates the recruitment of ESCRT to APs to catalyze their closure by controlling an Atg17-Snf7 interaction. Thus, we identify a regulator, a factor, and a molecular mechanism important for AP closure. Abbreviations: AP: Autohagosome; Atg: autophagy-related gene; ESCRT: the endosomal sorting complex required for transport; ILVs: intralumenal vescicles.