Small but mighty: Atg8s and Rabs in membrane dynamics during autophagy

Autophagy is a degradative pathway during which autophagosomes are formed that enwrap cytosolic material destined for turnover within the lytic compartment. Autophagosome biogenesis requires controlled lipid and membrane rearrangements to allow the formation of an autophagosomal seed and its subsequent elongation into a fully closed and fusion-competent double membrane vesicle. Different membrane remodeling events are required, which are orchestrated by the distinct autophagy machinery. An important player among these autophagy proteins is the small lipid-modifier Atg8. Atg8 proteins facilitate various aspects of autophagosome formation and serve as a binding platform for autophagy factors. Also Rab GTPases have been implicated in autophagosome biogenesis. As Atg8 proteins interact with several Rab GTPase regulators, they provide a possible link between autophagy progression and Rab GTPase activity. Here, we review central aspects in membrane dynamics during autophagosome biogenesis with a focus on Atg8 proteins and selected Rab GTPases.

Automated summary

Autophagy is a degradative pathway involving controlled lipid and membrane rearrangements to form autophagosomes for turnover within the lytic compartment. Atg8 proteins play a key role in autophagosome biogenesis and interact with various Rab GTPase regulators, potentially linking autophagy progression with Rab GTPase activity. This review focuses on membrane dynamics during autophagosome biogenesis, highlighting the role of Atg8 proteins and selected Rab GTPases.