Zhang Chengqi, Ren Xuexiang, Wang Xintong, Wan Qiong, Ding Kejian, Chen Li
Key Laboratory of Biology and Sustainable Management of Plant Diseases and Pests of Anhui Higher Education Institutes, College of Plant Protection, Anhui Agricultural University, Hefei, China.
Institute of Plant Protection and Agro-Products Safety, Anhui Academy of Agricultural Sciences, Hefei, China.
Front Microbiol. 2020 Jan 9;10:2970. doi: 10.3389/fmicb.2019.02970. eCollection 2019.
Rad50 is a member of the double strand break repair epistasis group of proteins that play important roles in regulating DNA damage checkpoint signaling, telomere maintenance, homologous recombination and non-homologous end-joining in eukaryotes. However, the function of Rad50 in fungal plant pathogens remains unknown. In this study, we report the functional investigation of FgRad50 in the wheat head blight pathogen . FgRad50 is an ortholog of Rad50 that could restore the sensitivity of the yeast Rad50 mutant to DNA damage agents. The deletion mutant (ΔFgRad50) exhibited defective vegetative growth, asexual/sexual development and virulence, as well as disrupted deoxynivalenol biosynthesis. Moreover, deletion of resulted in hypersensitivity to DNA damage agents. Unexpectedly, FgRad50 plays a key role in responses to cell wall-damaging agents by negatively regulating phosphorylation of FgMgv1, a MAP kinase in the cell wall integrity (CWI) pathway. Taken together, these results suggest that FgRad50 plays critical roles in fungal development, virulence and secondary metabolism in , as well as CWI and the DNA damage response.
Rad50是双链断裂修复上位性蛋白家族的成员之一，该家族蛋白在真核生物中调控DNA损伤检查点信号传导、端粒维持、同源重组和非同源末端连接等过程中发挥重要作用。然而，Rad50在真菌植物病原体中的功能尚不清楚。在本研究中，我们报道了对小麦赤霉病病原体中FgRad50的功能研究。FgRad50是Rad50的直系同源物，能够恢复酵母Rad50突变体对DNA损伤剂的敏感性。缺失突变体（ΔFgRad50）表现出营养生长缺陷、无性/有性发育缺陷和毒力缺陷，同时脱氧雪腐镰刀菌烯醇生物合成也受到破坏。此外，缺失还导致对DNA损伤剂高度敏感。出乎意料的是，FgRad50通过负调控细胞壁完整性（CWI）途径中的丝裂原活化蛋白激酶FgMgv1的磷酸化，在对细胞壁损伤剂的应答中起关键作用。综上所述，这些结果表明FgRad50在该真菌的发育、毒力和次生代谢以及CWI和DNA损伤应答中起关键作用。
