Genetic studies of Arabidopsis autophagy-related 8 family show overlapping roles in cell cleanup

Inactivation of all nine ATG8 loci in Arabidopsis thaliana reveals that Arabidopsis isoforms largely overlap in their functions controlling autophagic flux.

• Arabidopsis ATG8 isoforms demonstrate functional redundancy unlike distinct roles seen in mammalian ATG8 family members.
• Combinatorial mutations of ATG8 resulted in impaired autophagy and misregulated proteomes similar to other autophagy mutants.
• Interactions between all ATG8 representatives and Rab GTPase proteins are critical for binding to the autophagosome membrane.
• Such interactions may facilitate the fusion of autophagosomes with the vacuole but are not required for endosomal trafficking.
• This study creates a foundation for further exploration of individual ATG8 isoforms' roles in both canonical and noncanonical autophagy.

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