水稻抗病受体PigmR介导的广谱抗病信号途径解析

Rice blast is one of the most important and widespread disease of rice in our country. To identify and utilize the broad-spectrum or durable resistance resource and genes were considered the most economical and effective approach to control rice blast disease. The rice blast resistance gene Pigm was identified and cloned by screening the resistance resources on the blast nursery in the past years, characterized by durable and broad spectrum resistance in all rice-cultivated regions. Our study suggested that epigenetic regulation of paired antagonistic receptor NLR receptor confer broad-spectrum and durable resistance with yield balance. Now the broad spectrum resistance molecular mechanism of Pigm conferring to rice blast is not definite, henceforth it is worth of being investigated urgently. This issue focus on dissecting the PigmR-induced resistance mechanism by using the two strategies of genetics and Yeast-two hybrid system to screening the spi (suppressor of PigmR) and PIP(PigmR-interacting Protein), further the biological function of the SPI and PIP is studied intensively depending on the molecular genetics and biochemistry approaches, further establish the Pigm resistance signal transduction system, and shed light on the broad-spectrum resistance mechanism of PigmR, established the new resistant signal transduction network, ultimately which may provide new useful resistance genes and theoretical basis of carrying on broad spectrum resistance breeding by molecular design.

稻瘟病是我国各稻区的最重要的病害之一，选育广谱持久抗病品种是最经济有效的生产方式。但广谱抗病基因发掘与机制研究滞后，抗瘟性育种存在瓶颈问题。申请者通过长期的研究，克隆并功能鉴定了广谱持久的抗稻瘟病位点Pigm，该位点采用新的表观遗传调控方式调节一对拮抗的NLR免疫受体蛋白控制水稻广谱抗病与产量的平衡。但对PigmR介导的广谱抗病机制尚不清楚。本项目通过筛选PigmR的感病抑制子spi (suppressor of PigmR)和PigmR互作蛋白PIP（PigmR-interacting proteins）的策略，分别从分子遗传学和生物化学的角度详细解析SPI和PIP蛋白的生物学功能，解析Pigm广谱抗病机理，建立Pigm介导的广谱抗病信号转导网络，发现新的禾本科作物抗病调控新机制，为进一步的广谱抗病分子设计育种奠定理论基础并提供新的有重要应用价值的抗病基因。

稻瘟病是影响水稻产量的重要病害，控制该病害最经济有效的措施种植抗病品种。尽管已分离了30多个抗病基因，但绝大多数抗病基因控制的抗谱较窄，很容易被病原菌克服导致水稻品种的抗性丧失，因此急需鉴定分离广谱抗病基因，阐明广谱抗病的分子机制，为当前的水稻抗病育种提供有效抗病基因资源和理论技术支持。本项目在完成水稻广谱抗病基因Pigm克隆和功能分析的基础上，深入解析免疫受体PigmR激发广谱抗病的分子机制。通过高通量的酵母双杂交体系筛选PigmR互作蛋白PIBPs（Pigm-interacting and Blast resistance Proteins），采用生化、分子生物学、细胞生物学以及分子遗传学方法深入研究PIBP1调控免疫受体PigmR激发广谱抗病的分子机理，揭示PigmR调控广谱抗病的分子网络。同时鉴定分离广谱抗稻瘟病基因，建立高效的水稻广谱抗病分子育种技术体系，为水稻广谱抗病育种提供新的基因资源和理论技术支持。