禾谷镰刀菌组蛋白乙酰转移酶FgHat1在DON毒素生物合成中的功能

The histone acetyltransferase FgHat1 is important for DON biosynthesis in Fusarium graminearum

由禾谷镰刀菌引起的小麦赤霉病是小麦最主要的真菌病害之一。禾谷镰刀菌侵染小麦时分泌脱氧雪腐镰刀菌烯醇(DON)真菌毒素,威胁人畜健康。本研究通过对组蛋白乙酰转移酶基因FgHAT1的功能研究,发现该基因编码的蛋白定位于细胞核并调控组蛋白H4的乙酰化。Fghat1敲除突变体在生长发育和致病过程中表现正常,但毒素合成存在显著缺陷。敲除FgHATI导致参与DON毒素合成的TRI基因转录水平降低,突变体产毒相关的细胞分化也表现异常。外源添加cAMP可以有效回复突变体的产毒缺陷,表明FgHat1对毒素的调控与cAMP信号通路有关。研究结果表明组蛋白表观修饰和胞内信号通路之间存在联系,这两者的交叉互作对DON毒素合成的精确调控至关重要。

Fusarium head blight(FHB),caused by Fusarium graminearum,is one of the most important fungal diseases of wheat.F.graminearum produces deoxynivalenol(DON)during plant infection which is harmful to human and animal health.In this study,we functionally characterized a histone acetyltransferase FgHat1 and found that it was localized in the nucleus to acetylate histone 4.Although the Fghat1 deletion mutant was normal in vegetative growth,asexual and sexual development,and pathogenicity,it had severe defects in DON production.Not only TRI genes expression,but also DON associated cellular differentiation was affect by deletion of FgHATI.Exogenous treatment of cyclic adenosine monophosphate(cAMP)rescued the defects of Fghat1 deletion mutant in DON production,indicating a relationship between FgHat1 and cAMP signaling.Taken together,FgHat1 is associated with cAMP signaling to regulate DON biosynthesis in F.graminearum.