Investigating the Pmk1 MAPK cascade in rice blast fungus

世界粮食供应面临着气候变化、水资源短缺以及农业病虫害的压力。稻瘟病菌是水稻上最具破坏性的病害之一，也是最近亚洲小麦稻瘟病爆发的病原。稻瘟病的感染始于孢子落在叶片表面，附着并发芽。疏水性的叶表面触发胚芽发育附着胞，附着胞是一种单细胞感染结构，产生穿透水稻叶表面所需的巨大膨压。了解附着胞的发育过程对于制定防治稻瘟病和其他重要谷物病害的策略具有重要意义。这个博士项目将研究有丝分裂原活化蛋白激酶Pmk 1的作用，Pmk 1在附着胞发育中起着至关重要的作用。PMK 1基因的缺失消除了真菌的致病性。关于Pmk 1 MAPK通路的上游组分如何被激活，或者激酶如何精确地发挥其活性，我们知之甚少。该项目建立在最近的工作基础上，该工作已经建立了用于分析Pmk 1途径的磷酸蛋白质组学方法，首次揭示了其直接靶点（Oses-Ruiz et al.，2021 Nat Microb 6：1383-97）。

The world's food supply is under pressure from climate change, shortages of water as well as agriculture pests and diseases. One of the most devastating diseases of rice is caused by blast fungus (Magnaporthe oryzae), which also is the causal agent of the recent wheat blast outbreak in Asia. Rice blast infections start when spores land on leaf surfaces, attach and germinate. The hydrophobic leaf surface triggers germlings to develop an appressorium, a single celled infection structure that generates enormous turgor pressure required to penetrate the rice leaf surface. Understanding how appressoria develop is important to devise strategies to prevent rice blast disease and other important cereal diseases. This PhD project will investigate the role of the mitogen-activated protein kinase, Pmk1, which plays an essential role in appressorium development. Deletion of the PMK1 gene abolishes pathogenicity of the fungus. Very little is known regarding how upstream components of the Pmk1 MAPK pathway are activated, or how the kinase precisely exerts its activity. This project builds on recent work that has established phosphoproteomic methods for analysing the Pmk1 pathway, revealing its direct targets for the first time (Oses-Ruiz et al., 2021 Nat Microb 6:1383-97).