C2H2锌指转录因子FpCzf7参与假禾谷镰孢的生长和致病性

Role of C2H2 Zinc Finger Transcription Factor FpCzf7 in the Growth and Pathogenicity of Fusarium pseudograminearum

假禾谷镰孢引起的小麦茎基腐病已成为威胁我国小麦安全生产的重要病害,但是对假禾谷镰孢致病的机理还了解的比较少。C2H2锌指转录因子在人、植物和真菌中广泛分布,调控生长、发育和逆境胁迫等多种生理过程。本研究在假禾谷镰孢中鉴定到一个编码C2H2锌指转录因子的基因FpCzf7,利用PEG介导的原生质体转化,获得FpCzf7基因缺失的突变体(Δfpczf7)。生物学表型分析发现,与野生型(WT)和回补菌株(Δfpczf7-cp)相比,Δfpczf7在PDA培养基上的菌丝生长速率明显减慢、气生菌丝减少;在CMC液体中的分生孢子产量减少,但是分生孢子形态和萌发无差异。致病性测定结果显示,与WT和Δfpczf7-cp相比,Δfpczf7在大麦叶片、小麦胚芽鞘和小麦穂部的致病性均显著降低,DON毒素合成明显减少。综上所述,FpCzf7参与假禾谷镰孢的生长、产孢、致病性和毒素的产生。

Fusarium crown rot caused by Fusarium pseudograminearum has become one of the most destructive diseases of wheat in China.However,its molecular mechanism of pathogenicity is known little.C2H2 zinc finger transcription factors have been characterized from a wide variety of organisms,including animals,plants and fungi,and they are involved in the physiological processes such as growth,development and stress responses.In this study,a gene FpCzf7 encoding C2H2 zinc finger transcription factor was identified,and its deletion mutants(Δfpczf7)was obtained by PEG-mediated genetic transformation.Further analysis revealed thatΔfpczf7 mutants grew significantly slowly on PDA plates and less aerial hyphae compared with that of wild type(WT)and the complement strains(Δfpczf7-cp).Conidiation of the FpCzf7 deletion mutant in CMC liquid reduced as well,but their conidia morphology and germination were normal.Also,Compared to WT andΔfpczf7-cp,the pathogenicity caused by the FpCzf7 deletion mutant decreased on wheat coleoptile and spike and barley leaves,and DON toxin production reduced in theΔfpczf7 strain.Collectively,these results indicate that FpCzf7 is involved in growth,conidiation and pathogenicity and toxin production in F.pseudograminearum.