Interception of the fungal haustorium by the plant broad-spectrum resistance protein RPW8 (II)

许多真菌和卵菌病原体侵入植物具有称为吸器的专门感染结构，吸器从宿主细胞获得营养，并且是病原体可引起严重植物病害的机制。作为回应，植物进化出了复杂的防御机制来对抗这种感染。宿主-病原体识别和防御信号传导的机制已被广泛研究，然而，很少有人知道分子战争的机制，在宿主-病原体的结构界面被称为外吸器膜（EHM）。研究人员发现，RPW 8是一种在植物拟南芥中赋予对白粉病广谱抗性的蛋白质，它特异性地针对EHM，EHM包裹着白粉病的吸器;在这个位置，RPW 8激活防御以限制吸器。使用突变，细胞生物学，遗传学和生物化学方法的组合，研究人员在该项目中的目标是了解RPW8.2如何激活这种抗性。具体来说，研究人员将定义RPW8.2中功能重要的基序和单个氨基酸，确定将RPW8.2靶向EHM的运输线索，并表征2C型蛋白磷酸酶在RPW8.2介导的防御调控中的作用。该项目的结果不仅将阐明RPW8.2介导的广谱抗霉菌性的分子基础，还将为靶向蛋白质运输作为植物先天免疫的关键组成部分提供新的机制见解。形成吸器的真菌和卵菌病原体对世界粮食安全构成持续威胁。该项目的发现将有助于设计针对这些病原体的新抗性策略，并有可能提高作物产量和环境保护。该项目将为高中生和本科生提供科学培训和研究机会，特别是来自代表性不足群体的学生;它还将为一名研究生和一名博士后助理提供广泛的研究培训，为他们从事科学事业做好准备。

Many fungal and oomycete pathogens invade plants with a specialized infection structure named the haustorium, which derives nutrients from the host cell and is a mechanism by which pathogens can cause serious plant diseases. In response, plants have evolved elaborate defense mechanisms to fight against such infection. Mechanisms of host-pathogen recognition and defense signaling have been extensively studied; however, very little is known about the mechanisms of molecular warfare at the host-pathogen structural interface known as the extra-haustorial membrane (EHM). The investigators discovered that RPW8, a protein conferring broad-spectrum resistance against powdery mildew in the plant Arabidopsis , is specifically targeted to the EHM, which encases the haustorium of powdery mildew ; in this location, RPW8 activates defenses to constrain the haustorium. Using a combination of mutational, cell biological, genetic and biochemical approaches, the investigators aim in this project to understand how RPW8.2 activates this resistance. Specifically, the investigators will define functionally important motifs and individual amino acids in RPW8.2, identify the trafficking cues for targeting RPW8.2 to the EHM, and characterize the role of a protein phosphatase type 2C in regulation of RPW8.2-mediated defense. Results from this project will not only elucidate the molecular basis of RPW8.2-mediated broad-spectrum mildew resistance but also provide fresh mechanistic insight into targeted protein trafficking as a critical component of plant innate immunity. Haustorium-forming fungal and oomycete pathogens pose constant threats to the world's food security. Discoveries from this project will help engineer novel resistance strategies against these pathogens , with the potential for improved crop production and environmental protection. This project will provide science training and research opportunities for high school and undergraduate students, especially those from under-representative groups; it will also provide extensive research training for one graduate student and one postdoctoral associate to prepare them for careers in science.