FgHAT2 is involved in regulating vegetative growth, conidiation, DNA damage repair, DON production and virulence in Fusarium graminearum

Histone lysine acetylation is catalyzed by acetyltransferases (HATs), which is important in regulating gene expression and physiological function in eukaryotic cells. HATs can be classified into two main types: A- and B-type HATs. Recently, in Fusarium graminearum, it has been reported that A-type HATs are involved in hyphal development, conidiation, sexual reproduction and virulence. However, the biological roles of B-type HATs are unknown. Here we report the identification and characterization of two B-type HATs (FgHat1 and FgHat2) in F. graminearum. Targeted deletion of FgHAT1 did not result in any detectable phenotypes. However, ΔFghat2 mutants were severely defective in vegetative growth, conidia production and morphogenesis, deoxynivalenol (DON) biosynthesis and virulence. Interestingly, deletion of FgHAT2 resulted in significantly increased sensitivity to the DNA-damaging agent methyl methanesulfonate (MMS). Furthermore, double deletion mutants (ΔFghat1ΔFghat2) displayed similar phenotypes to the ΔFghat2 mutants. Taken together, we conclude that FgHat2 but not FgHat1 plays essential roles in regulating morphogenesis, DNA damage repair, DON production and virulence in F. graminearum.