The transcription factor FgCrz1A is essential for fungal development, virulence, deoxynivalenol biosynthesis and stress responses in Fusarium graminearum
The transcription factor FgCrz1A is essential for fungal development, virulence, deoxynivalenol biosynthesis and stress responses in Fusarium graminearum
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DOI：
10.1007/s00294-018-0853-5
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发表时间：
2019-02-01
期刊：
影响因子：
2.5
通讯作者：
Ding, Kejian
中科院分区：
文献类型：
--
作者：
Chen, Li;Tong, Qiang;Ding, Kejian
锌指转录因子Crz1在许多生物体中是钙依赖信号转导途径的重要下游调节因子。Crz1在小麦枯萎病病原菌中的作用尚不清楚。在这项研究中，我们鉴定并功能表征了FgCrz1A，酵母Crz1的潜在同源物。缺失突变体FgCrz1A在基本培养基上菌丝生长缓慢，分生孢子形成和有性生殖完全受阻。FgCrz1A对金属阳离子Ca2+、Mg2+、Mn2+和Li+的敏感性增加，但对Zn2+的敏感性降低。出乎意料的是，缺失突变体比野生型真菌更能抵抗渗透胁迫和细胞壁破坏剂。致病性试验表明，突变体对开花小麦穗和玉米丝的毒力显著降低，这与脱氧雪腐镰刀菌醇产量减少的结果一致。此外，gfp融合的FgCrz1A主要定位于细胞核，是参与分生发生的abaA和wetA的转录诱导所必需的，也是有性生殖过程中MAT位点的基因和脱氧雪腐镰刀菌醇生物合成的TRI基因的转录诱导所必需的。综上所述，研究结果表明FgCrz1A不仅在调控F. graminearum的真菌发育、次生代谢和毒力方面发挥关键作用，而且在多种胁迫响应中发挥关键作用。
The zinc finger transcription factor Crz1 is an important downstream regulator of calcium-dependent signal transduction pathways in many organisms. The function of Crz1 in the wheat-head blight pathogen Fusarium graminearum remains unclear. In this study, we identified and functionally characterised FgCrz1A, a potential ortholog of yeast Crz1. The deletion mutant FgCrz1A exhibited slower hyphal growth on basic medium, and conidia formation and sexual reproduction were completely blocked. FgCrz1A also displayed increased sensitivity to metal cations Ca2+, Mg2+, Mn2+ and Li+, but decreased sensitivity to Zn2+. Unexpectedly, the deletion mutant was more resistant to osmotic stress and cell wall-damaging agents than the wild-type fungus. Pathogenicity assays showed that virulence of the mutant was dramatically decreased on flowering wheat heads and corn silks, consistent with the observed reduction in deoxynivalenol production. Moreover, GFP-fused FgCrz1A was mainly localised in the nucleus, and was required for transcriptional induction of abaA and wetA that are involved in conidiogenesis, as well as genes of the MAT locus during sexual reproduction, and TRI genes responsible for deoxynivalenol biosynthesis. Taken together, the results indicate that FgCrz1A plays critical roles not only in regulating fungal development, secondary metabolism and virulence in F. graminearum, but also in multiple stress responses.