A core effector UV_1261 promotes Ustilaginoidea virens infection via spatiotemporally suppressing plant defense
A core effector UV_1261 promotes Ustilaginoidea virens infection via spatiotemporally suppressing plant defense
复制标题
核心效应子 UV_1261 通过时空抑制植物防御促进绿黑粉菌感染
DOI：
10.1186/s42483-019-0019-5
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发表时间：
2019-01-01
影响因子：
3.4
通讯作者：
Wang, Wen-Ming
中科院分区：
文献类型：
--
作者：
Fan, Jing;Du, Ning;Wang, Wen-Ming
稻曲病是一种世界性的水稻破坏性谷物病害，其特征是在稻花中形成假黑粉病。在这里，我们鉴定了一个小的分泌性蛋白UV_1261，它与该病的病原菌--稻瘟病菌的毒力有关。UV_1261序列在不同菌株中高度保守，在其他真菌中不存在。UV_1261编码一种针对植物叶绿体的蛋白质。在发病过程中，其表达呈双峰型。UV_1261在烟草和拟南芥中的异位表达抑制了flg22诱导的ROS爆发，抑制了抗病相关基因的表达，提高了拟南芥对白粉病的敏感性。通过外源siRNA处理下调UV_1261的表达，导致假黑粉球数量减少。稳定地击倒UV_1261导致稻花中较少的假黑粉球数量与较高的防御相关基因的表达有关。综上所述，我们的研究结果表明，UV_1261是病毒菌的核心效应因子，对水稻花的毒力和抑制防御是必不可少的，因此可能成为控制水稻稻曲病的潜在分子靶标。
False smut is a destructive grain disease of rice worldwide, characterized by false smut balls formed in rice flowers. Here we identified a small secreted protein UV_1261 contributing to virulence of Ustilaginoidea virens, the causal agent of this disease. The sequence of UV_1261 was highly conserved among isolates of U. virens and absent in other fungi. UV_1261 encodes a protein targeted to plant chloroplasts. Its expression exhibited a bimodal pattern during pathogenesis. Ectopic expression of UV_1261 in Nicotiana benthamiana and Arabidopsis led to suppression of flg22-induced ROS burst, callose deposition, and expression of defense-related genes, as well as enhanced susceptibility to powdery mildew in Arabidopsis. Down-regulation of UV_1261 via exogenous siRNA treatment resulted in reduced number of false smut balls. Consistently, stably knocking-down UV_1261 caused less number of false smut balls associated with higher expression of defense-related genes in rice flower. Taken together, our data demonstrate that UV_1261 is a core effector of U. virens essential for virulence and suppressing defense in rice flower, and thus may serve as a potential molecular target for controlling rice false smut disease.