条锈菌激发子Pst_EC1诱导寄主小麦防御反应的分子机理

由小麦条锈菌引起的小麦条锈病严重影响我国小麦生产。小麦条锈菌频繁变异导致抗病品种丧失抗性，常引发病害爆发流行，因而寻找新型的持久病害防治策略已迫在眉睫。研究发现，病原菌与植物互作中，会产生激发子触发寄主的防御反应，提高植物的抗病性，利用病菌激发子防治病害已经成为重要的研究策略。前期，课题组在通过吸器全转录组筛选、鉴定分泌蛋白的基础上，获得了一个能够在寄主小麦和非寄主植物中诱导细胞坏死的分泌蛋白Pst_EC1，推测其为条锈菌候选激发子。为此，本项目拟进一步通过瞬时表达、基因沉默、酵母双杂交、免疫胶体金等技术方法深入解析其在小麦与条锈菌互作中的功能；揭示其在细胞水平上的时空表达特征；鉴定Pst_EC1互作的小麦蛋白，并分析互作基因的功能及功能结构域，从而揭示条锈菌激发子Pst_EC1诱导植物防御反应的分子机理。为阐明小麦与条锈菌的互作机制奠定基础，并为制定小麦条锈病防治新策略提供理论依据。

Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst) has brought severe damage to wheat production in China. The rapid virulence variation of Pst leads to the “resistance loss” of the present wheat resistant cultivars, which frequently results in the epidemic of the disease. Thus, it is extremely urgent to develop new strategies for durable control of the disease. During the interaction between plants and pathogens, elicitors are produced by pathogens to trigger the defense response in plants. And application of the pathogen elicitors in disease control through enhancing the resistance of plants has proved to be one important research strategy. On the basis of screening and identification of secreted effectors in Pst haustoria transcriptome, we have obtained a secreted protein Pst_EC1 that could trigger significant cell death in wheat and several non-host plants of Pst, suggesting a general elicitor activity. Thus, in this project, we plan to further study the exact role of Pst_EC1 in the interaction between wheat and Pst, reveal its temporal and spatial expression characteristics in cellular level, identify its host targets and analyze the roles of the target genes via transient expression, gene silencing, yeast two-hybrid system, immune colloidal gold technique and so on. The information obtained in this study will reveal the mechanism of the induced defense response by the elicitor Pst_EC1, add further insights on the mechanism of interaction between wheat and Pst. Moreover, it will provide theoretical basis for developing new strategies for durable control of wheat stripe rust.