由活体营养专性寄生真菌条形柄锈菌小麦专化型引起的条锈病是小麦生产上的重大病害，该病原菌往往通过菌丝特化的营养吸收器官-吸器分泌大量的毒性因子进入寄主细胞，调控寄主的免疫。因此，开展吸器分泌蛋白的研究对揭示病菌致病机理意义重大。但目前对吸器分泌那些类型的蛋白进入寄主细胞，通过什么方式抑制寄主的防御反应等仍不清楚，加之条锈菌不能人工培养，遗传转化困难，导致对该病原菌的致病机理缺乏深入了解。因此，本项目拟在前期通过大规模筛选条锈菌分泌蛋白，获得了2个可抑制寄主小麦PTI和ETI效应蛋白的基础上，深入开展条锈菌效应蛋白转运、效应蛋白在条锈菌侵染寄主中的时空特征及毒性作用、效应蛋白互作靶标及其功能、效应蛋白生化功能等方面研究内容，以期揭示条锈菌效应蛋白调控寄主的作用机理，为深入揭示条锈菌致病及其变异机理提供理论依据，进而为开辟小麦条锈病持久控制新策略奠定基础。

Wheat stripe rust fungus (Puccinia striiformis Westend. f. sp. tritici Eriks, Pst), an obligate bitrophic fungus, causes serious disease and completely depends on their living host tissue for growth and reproduction. During infection, Pst forms a specialized infection structure, the haustorium, to take nutrients from their host, and establish an intimate feeding relationship. During the interactions between wheat and stripe rust fungus, a series of secreted proteins are released from haustoria into host cells to modulate host immunity. However, little is known about the mechanism of how the secreted proteins enter into and function inside plant cells to promote disease. Meanwhile, the lack of a stable transformation system has been an impediment to the genetic manipulation of stripe rust, which limits the understanding of Pst pathogenesis mechanism. So we plan to make an in-depth study of the effectors in Pst based on the two candidate effectors, which suppress both PTI and ETI in the wheat-PST interaction, obtained by previous large-scale screening of secreted proteins. Furthermore, we will reveal their translocation, temporal and spatial characteristic and biochemical function during infection. Also we will resolve that how these effectors modify the host immunity by identification and functional analysis of their host targets. Together, these studies will substantially provide new insights in revealing the pathogenicity mechanism of the stripe rust fungus and offer a new strategy to engineer durable resistance cultivars through the modulation of pathogen genes, which is of great theoretical and practical significance for the sustainable control of the stripe rust.

由活体营养专性寄生真菌条形柄锈菌小麦专化型引起的条锈病是小麦生产上的重大病害，该病原菌往往通过菌丝特化的营养吸收器官-吸器分泌大量的毒性因子进入寄主细胞，调控寄主的免疫。因此，开展吸器分泌蛋白的研究对揭示病菌致病机理意义重大。但目前对吸器分泌那些类型的蛋白进入寄主细胞，通过什么方式抑制寄主的防御反应等仍不清楚，加之条锈菌不能人工培养，遗传转化困难，导致对该病原菌的致病机理缺乏深入了解。因此，本项目在前期通过大规模筛选条锈菌分泌蛋白，获得了2个可抑制寄主小麦PTI和ETI效应蛋白的基础上，深入开展了条锈菌效应蛋白转运、效应蛋白在条锈菌侵染寄主中的时空特征及毒性作用、效应蛋白互作靶标及其功能、效应蛋白生化功能等方面研究。取得了重要进展，发现条锈菌效应蛋白Pst-8853和Pst-4941可通过吸器和菌丝分泌到寄主细胞，负责转运的结构域位于N端；揭示了Pst-8853和Pst-4941在条锈菌侵染小麦过程中发挥重要作用，并发现二者存在共同的互作靶标，抑制寄主的免疫；发现Pst-8853和Pst-4941可在小麦抗病单基因系 Yr1和Yr27中诱发HR，并通过与靶标TAISP和TaCP互作激发寄主的免疫；获得了Pst-8853和Pst-4941高纯度的蛋白，并完成了效应蛋白的核磁共振谱的采集。上述研究对深入揭示条锈菌效应蛋白调控寄主的作用机理提供了依据，进而为开发小麦条锈病防控新策略奠定了基础。