FgVAC1 is an Essential Gene Required for Golgi-to-Vacuole Transport and Fungal Development in Fusarium graminearum

Fusarium graminearum is an important plant pathogen that causes head blight in cereal crops such as wheat, barley, and rice worldwide. In this study, we identified and functionally characterized FgVAC1, an essential gene in F. graminearum that encodes a Rab5 effector involved in membrane tethering functions. The essentiality of FgVAC1 was confirmed through a conditional promoter replacement strategy using the zearalenone-inducible promoter (P_ZEAR). Cytological analyses revealed that FgVac1 colocalizes with FgRab51 on early endosomes and regulates the proper transport of the vacuolar hydrolase FgCpy1 to the vacuole. Suppression of FgVAC1 led to inhibited vegetative growth, reduced asexual and sexual reproduction, decreased deoxynivalenol (DON) biosynthesis, and diminished pathogenicity. Our findings highlight the significant role of FgVac1 in vacuolar protein sorting, fungal development, and plant infection in F. graminearum.