Analysis of the Role of pH Regulation in the Secretion of Proteins and the Virulence of the Apoplast-Infecting Fungus Mycosphaerella Graminicola

感染植物的真菌既是一种经济威胁，也是研究基本生物过程的有用系统。 一些真菌植物病原体使用的一种简单的感染模式是感染叶细胞之间的空间，质外体。 尽管感染机制并不复杂，但关于这些真菌如何能够进入宿主，避免检测并获得营养，这些事件共同构成发病机制，仍有许多问题尚未解决。 该项目的具体目的是确定环境pH信号在小麦质外体感染真菌（禾生球腔菌）的发病机制中所起的作用。 M.草生菌是用于研究的优良病原体，因为它在培养物中表现出两种可能的生长类型（单细胞和丝状），在其植物宿主中表现出两个不同的生长阶段（活体营养型（其中植物细胞未受损）和坏死营养型（其中植物细胞受损）），并且具有测序的基因组。 将产生缺乏pH信号级联的组分的突变真菌，并评价其在各种pH条件下和植物宿主中的生长。 该项目将依靠分子、生物化学和遗传学方法。 因此，pH在影响感染过程中的作用以及M. Graminicola将被理解。 该项目将提供有关这种真菌中新的信号传导机制的信息，这可能更广泛地适用于其他真菌植物病原体。这项工作的更广泛的影响还包括为劳伦斯理工大学的本科生提供研究经验。

Fungi which infect plants represent both an economic threat and a useful system for the study of fundamental biologic processes. One simple mode of infection used by some fungal plant pathogens is the infection of the space between the cells of the leaf, the apoplast. Even though the infection mechanism is not complex, there are many questions which remain unanswered about how these fungi are able to enter the host, avoid detection, and gain nutrients, events which together comprise pathogenesis. The specific aim of this project is to determine the role that ambient pH signaling plays in the pathogenesis of an apoplast-infecting fungus (Mycosphaerella graminicola) on wheat. M. graminicola is an excellent pathogen for investigation because it exhibits two possible types of growth in culture (single celled and filamentous), two different phases of growth in its plant host (biotrophic (where plant cells are not damaged) and necrotrophic (where plant cells are damaged) and has a sequenced genome. Mutant fungi which lack components of the pH signaling cascade will be created and evaluated with respect to growth under various pH conditions and in plant hosts. The project will rely upon molecular, biochemical and genetic approaches. As a result, the role that pH is playing in influencing the infection process and how pH is sensed by M. graminicola will be understood. The project should provide information about a novel signaling mechanism in this fungus which may be more broadly applicable to other fungal plant pathogens. The broader impacts of this work also include providing research experiences for undergraduate students at Lawrence Technological University.