Tang Ying, Zhu Pinkuan, Lu Zhengyu, Qu Yao, Huang Li, Zheng Ni, Wang Yiwen, Nie Haozhen, Jiang Yina, Xu Ling
School of Life Sciences, East China Normal University, Shanghai 200241, China.
Microorganisms. 2020 Mar 5;8(3):365. doi: 10.3390/microorganisms8030365.
belongs to one of the phylogenetical subgroups of the species complex and is epidemically predominant in the East Asia area. The life cycle of is significantly regulated by light. In this study, the fungal blue light receptor white collar complex (WCC), including FaWC1 and FaWC2, were characterized in . The knockout mutants Δ and Δ were generated by replacing the target genes via homologous recombination events. The two mutants showed similar defects in light-induced carotenoid biosynthesis, UV-C resistance, sexual fruiting body development, and the expression of the light-responsive marker genes, while in contrast, all these light responses were characteristics in wild-type (WT) and their complementation strains, indicating that FaWC1 and FaWC2 are involved in the light sensing of . Unexpectedly, however, the functions of and diverged in regulating virulence, as the Δ was avirulent to the tested host plant materials, but Δ was equivalent to WT in virulence. Moreover, functional analysis of FaWC1 by partial disruption revealed that its light-oxygen-voltage (LOV) domain was required for light sensing but dispensable for virulence, and its Zinc-finger domain was required for virulence expression but not for light signal transduction. Collectively, these results suggest that the conserved fungal blue light receptor WCC not only endows with light-sensing ability to achieve adaptation to environment, but it also regulates virulence expression by the individual component FaWC1 in a light-independent manner, and the latter function opens a way for investigating the pathogenicity mechanisms of this important crop disease agent.
属于该物种复合体的一个系统发育亚群，在东亚地区流行占主导地位。其生命周期受光显著调控。在本研究中，对该真菌的蓝光受体白领复合体（WCC），包括FaWC1和FaWC2进行了表征。通过同源重组事件替换靶基因产生了敲除突变体Δ和Δ。这两个突变体在光诱导的类胡萝卜素生物合成、抗UV-C能力、有性子实体发育以及光响应标记基因的表达方面表现出相似的缺陷，而相比之下，所有这些光反应在野生型（WT）及其互补菌株中是特征性的，表明FaWC1和FaWC2参与了该真菌的光感知。然而，出乎意料的是，FaWC1和FaWC2在调节毒力方面功能有所不同，因为Δ对测试的寄主植物材料无毒力，但Δ在毒力方面与WT相当。此外，通过部分破坏对FaWC1进行功能分析表明，其光氧电压（LOV）结构域是光感知所必需的，但对毒力是可有可无的，其锌指结构域是毒力表达所必需的，但对光信号转导不是必需的。总体而言，这些结果表明，保守的真菌蓝光受体WCC不仅赋予该真菌光感知能力以实现对环境的适应，而且它还通过单个组分FaWC1以光独立的方式调节毒力表达，后一种功能为研究这种重要作物病害病原体的致病机制开辟了一条途径。
