大豆中一个参与卵菌免疫反应的基因的研究

Phytophthora sojae is an oomycete pathogen of soybean, causing root rot of plant with an annual cost worldwide of $1-2 billion. Therefore, the research of interaction between the plant host and this pathogen has been increasingly important. Effector is a kind of biomolecule which is secreted by pathogen to suppress host immune defense system to help pathogen colonized in host cell. The effector usually attacks an interacting “target protein” to achieve the purpose of suppressing the plant immune response. Thus, it is an efficient method to identify the novel component of immune system by analyzing the interacting protein of effector in host cell. In this study, the soybean protein BLP1 will be systematically analyzed to identify whether it participates in plant immune response to oomycete , based on the previous results that BLP1 interacted with P. sojae effector Avr1c. Furthermore, experiments will be carried out to elucidate how Avr1c suppress the host cell immune response through BLP1 in molecular and biochemical level. This research will lay a theoretical foundation for breeding oomycete resistant soybean cultivars.

大豆疫霉菌 （Phytophthora sojae）是引起大豆根腐病的一种主要致病卵菌，全球每年造成的经济损失高达10至20亿美元。因此对于植物宿主与此病原菌之间的相互作用研究一直是植病工作的重点。效应因子是病原菌分泌的一种可以抑制宿主免疫防卫系统从而帮助其在宿主中定殖的生物分子。可以进入宿主细胞的效应因子通常通过与它们相互作用的“靶蛋白”达到抑制植物免疫反应的目的。因此，通过分析宿主细胞中与效应因子相互作用的靶蛋白从而鉴定植物参与免疫反应的组分是研究植物免疫系统的重要途径。本课题从我们发现的大豆中一个与大豆疫霉效应因子Avr1c相互作用的蛋白BLP1入手，系统地分析BLP1是否参与植物对卵菌的免疫过程，并拟从分子生化水平阐明Avr1c通过BLP1抑制植物免疫反应的机理，为培育抗卵菌大豆品种提供理论基础。

大豆疫霉病菌可以通过分泌效应因子来攻击大豆中的关键抗病组分从而起到阻碍大豆抗病目的。本研究对大豆中的一个候选抗病靶标基因进行研究，通过鉴定该基因表达谱，病原菌诱导表达谱，基因沉默后对抗病组分的影响以及与已知抗病组分之间的相互作用等实验证明了一个参与了植物对卵菌的抗病防卫反应的基因。通过Co-IP，BIFC，Y2H，GST Pull Down四种方法证明了效应因子与候选蛋白之间的相互作用，鉴定了效应因子可以阻止此蛋白与大豆抗病组分之间的相互作用。