Interaction between FgVPS26 and FgRab7 and Their Effect on the Synthesis of DON Toxin in Fusarium Graminearum

The biosynthesis of deoxynivalenol (DON) toxin is a secondary metabolic process regulated by multiple genes in Fusarium graminearum,and elucidating the regulatory roles of the related genes is conducive to the development of scientific prevention and control measures. In this study,yeast two-hybrid,real-time quantitative PCR and ELISA were employed to investigate the interaction between FgVPS26 and FgRab7 and their effect on the biosynthesis of DON toxin. The results showed that FgVPS26 could interact with activated FgRab7,but could not interact with the original state of FgRab7. The expression of FgVPS26 and FgRab7 genes could influence each other,and when one of the genes(FgVPS26 and FgRab7) was knocked out,the expression of the other gene decreased significantly compared with the level in wild-type strain PH-1. Additionally,deletion of FgVPS26 or FgRab7 gene also significantly affected the expression of Tri gene involved in DON toxin synthesis,which resulted in the decrease of DON toxin synthesis of mutant strains compared with that of wild type strain at the same growth stage. Our results suggested that FgVPS26 and FgRab7 could interact with each other and regulate the biosynthesis of DON toxin in Fusarium graminearum.