极体（Polarisome）复合体在禾谷镰刀菌致病过程中的作用机制研究

禾谷镰刀菌在侵染宿主植物的过程中，主要由伤口或气孔进入宿主细胞，随后通过菌丝的顶端延伸进行定殖，同时会分泌毒素DON及线性八肽（linear nonribosomal octapeptide），抑制或干扰宿主的免疫反应。极体（Polarisome）是一类包括Spa2、Bud6及Pea2三个核心亚基的多蛋白复合体，从酵母到丝状真菌高度保守，主要定位于菌丝顶端的顶体部位，参与细胞的极性生长及细胞极性的维持。基于这些研究基础，我们分析认为极体复合体在禾谷镰刀菌的侵染定殖过程中可能起重要调控作用。本项目拟通过遗传学、细胞生物学及蛋白质组学等方法解析极体复合体介导的极性生长、囊泡转运或分泌在禾谷镰刀菌致病过程中的作用机制，初步探索极体复合体调控毒素DON的合成、转运或分泌的分子机理。本项目研究结果将明确禾谷镰刀菌中极体复合体的生物学功能及致病机制，为小麦赤霉病防治新策略提供理论依据。

Fusarium graminearum is a plant pathogen and infects its hosts through vulnerable openings or the stomata, then colonizes the host cells through hyphal elongation or apical growth, and secretes mycotoxin DON and linear nonribosomal octapeptide to inhibit the immune response of its host. Polarisome is a multiprotein complex and conserved from yeast to filamentous fungi which involved in the establishment, maintenance and termination of polarized cell growth and included three core components Spa2, Pea2, and Bud6. Based on this knowledge, we speculate that the polarisome may play essential roles in invasion or colonize with its host in F. graminearum. Therefore, we set out to use genetics, cellular biology and proteomic strategies to investigate the molecular mechanism of polarisome mediated pathogenesis in F. graminearum in this project, and preliminary explore the molecular role of polarisome mediated DON synthesis, trafficking and secretion and provide novel insight into how polarisome regulates pathogenesis by modulating polarized growth, vesicle trafficking or secretion in F. graminearum. Results of this project will provide a new strategy for wheat scab disease.