小麦条锈菌引起的小麦条锈病是影响我国小麦安全生产的重要生物灾害。由于条锈菌毒性变异快，小麦品种抗性不断"丧失"，导致该病害频繁爆发。因而解析小麦与条锈菌互作机理，有针对性持久控制病害显得尤为迫切。在前期小麦与条锈菌互作全转录组分析中，获得了两个metacaspase I基因，它们在小麦与条锈菌亲和互作中诱导表达，沉默后可增强小麦抗病性，推测其与小麦感病性有关。而研究表明，metacaspase通过调控HR影响植物对病原菌的抗性。因此，本项目拟通过瞬时表达、基因沉默、酵母双杂交、RNAi等技术方法，借助酵母、短柄草等研究体系，深入解析其在小麦感条锈菌中作用，明确其caspase活性及在细胞坏死中的功能，鉴定其互作靶标，以揭示metacaspase I基因在小麦细胞坏死及感病中的作用机理，为阐明小麦与条锈菌互作机理奠定基础，进而为利用感病基因制定持久防治病害新策略提供理论依据和技术支撑。

Wheat stripe rust caused by Puccinia striiformis f. sp. tritici (Pst), is an important biological disaster, which severely affects the security of wheat production in China. The rapid virulence variation of Pst results in "resistance loss" of wheat cultivars, and leads to the frequent epidemic of the disease. So it is particularly urgent to reveal the mechanism of wheat and Pst interactions for durable disease control pertinently. In previous studies, we identified two metacasepase I genes by analyzing the whole transcriptome of wheat infected by Pst, which were significantly induced during the compatible wheat-Pst interactions. Silencing of them enhanced the resistance of wheat to Pst, indicating their roles in the susceptibility of wheat to Pst. Previous reports suggested that metacaspase could regulate the hypersensitive response (HR) in plants, and then affect the plant resistance to pathogens. Thus, in this project, we plan to further study the function of metacasepase I genes in the susceptible interaction of wheat and Pst, analyse their regulation roles in cell death and caspase activity, identify their target genes by using the yeast and Brachypodium research system via transient expression, gene silencing, yeast two hybrid, RNAi technique and so on. Our results will reveal the modulation mechanism of metacaspase I cell death and wheat susceptibility to Pst, and lay the foundation for clarifying the mechanism of wheat and stripe rust interactions, which will furthermore provide theoretical basis and technical support to develop new strategies to contro disease persistently.