Acetylated Vps1 initiates autophagy and regulates the sorting nexin dynamics essential for pathogenicity in Fusarium graminearum

Macroautophagy/Autophagy is a dynamic recycling process that maintains cellular homeostasis and is closely linked to Fungal development and pathogenicity. However, the mechanisms underlying the maintenance of Autophagy homeostasis remain largely unclear in phytopathogenic fungi. In this study, we identified the FgHat2-FgVps1-FgSnx4 module as a key regulator of Autophagy homeostasis in Fusarium graminearum. We show that the initiation of Autophagy requires acetylation of the dynamin-like GTPase FgVps1 at lysine 216 by the Histone Acetyltransferase FgHat2. This modification promotes the interaction between FgVps1 and the Autophagy protein FgAtg8 and facilitates the endosomal release of the sorting nexin FgSnx4. Released FgSnx4 is essential for directing FgAtg9 trafficking to the phagophore and for interacting with FgAtg8 through its N-terminal Atg8-family interacting motif (AIM), thereby ensuring proper modulation of FgAtg8 during Autophagy. Together, these findings reveal an acetylation-dependent mechanism that coordinates Autophagy, providing new insights into the regulation of Autophagy in phytopathogenic fungi. ABBREVIATIONS AIM: Atg8-family interacting motif; ATG: Autophagy related; CBB: Coomassie Brilliant Blue; CM: complete medium; CMAC: 7-amino-4-chloromethylcoumarin; Co-IP: co-immunoprecipitation; MM-N: minimal medium without nitrogen; PAS: phagophore assembly site; SNX: sorting nexin.