National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei, 430070, China; State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, Wuhan, Hubei, 430062, China.
National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei, 430070, China.
Plant Sci. 2021 Apr;305:110833. doi: 10.1016/j.plantsci.2021.110833. Epub 2021 Feb 3.
Cotton is one of the most important economic crops and is cultivated globally. Verticillium wilt, caused by the soil-borne hemibiotrophic fungus Verticillium dahliae, is the most destructive disease in cotton production for its infection strategies and great genetic plasticity. Recent studies have identified the accumulation of lignin is a general and basal defense reaction in plant immunity and cotton resistance to V. dahliae. However, the functions and regulatory mechanisms of transcription factors in cotton defense-induced lignification and lignin composition alteration were less reported. Here, we identified a WRKY transcription factor GhWRKY1-like from upland cotton (Gossypium hirsutum) as a positive regulator in resistance to V. dahliae via directly manipulating lignin biosynthesis. Further analysis revealed that GhWRKY1-like interacts with the promoters of lignin biosynthesis related genes GhPAL6 and GhCOMT1, and activates the expression of GhPAL6 and GhCOMT1, which led to enhanced total lignin especially S monomers biosynthesis. These results demonstrate that GhWRKY1-like enhances Verticillium wilt resistance via an increase in defense-induced lignification and broaden our knowledge of the roles of lignification and the lignin composition in plant defense responses.
棉花是全球最重要的经济作物之一。由土壤传播的半活体真菌大丽轮枝菌引起的黄萎病是棉花生产中最具破坏性的疾病，其侵染策略和强大的遗传可塑性是造成这一问题的主要原因。最近的研究表明，木质素的积累是植物免疫和棉花对大丽轮枝菌抗性的一种普遍而基本的防御反应。然而，转录因子在棉花防御诱导木质素形成和木质素组成改变中的功能和调控机制的相关报道较少。在这里，我们从陆地棉（Gossypium hirsutum）中鉴定出一个 WRKY 转录因子 GhWRKY1-like，它作为一个正向调控因子通过直接操纵木质素生物合成来抵抗大丽轮枝菌。进一步的分析表明，GhWRKY1-like 与木质素生物合成相关基因 GhPAL6 和 GhCOMT1 的启动子相互作用，并激活 GhPAL6 和 GhCOMT1 的表达，从而导致总木质素特别是 S 单体生物合成增强。这些结果表明，GhWRKY1-like 通过增加防御诱导的木质化来增强黄萎病抗性，拓宽了我们对木质化和木质素组成在植物防御反应中的作用的认识。
