水稻新类型抗飞虱基因克隆与功能研究

Planthopper is the most destructive insect pests that feed on rice plants. It sucks the sap from the rice phloem resulting in yield losses, even totally crop failure, which causes serious threats to rice production. With the rapid advances in rice functional genomic research, several important planthopper resistance genes have been isolated from wild rice and cultivated rice. Up to now, the insect-resistance genes have been isolated mainly encode two classes of proteins: one is cytosol-localized NB-LRR protein, the other is plasma membrane–localized lectin receptor kinases. The function of new type resistance gene remains obscure except Bph6, which encodes an exocyst-localized protein and confers broad-spectrum resistance to the brown planthopper (BPH) and white-backed planthopper (WBPH). The combination of different types of insect resistance genes is important for breeding rice varieties resistant to pests. Therefore, there are still urgent needs to characterize new types of resistance genes and elucidate resistance mechanisms. Here we propose to isolate and identification of new types of insect-resistance genes using map-based cloning from rice mutants induced by γ-ray irradiation. The objective of the project is to achieve more genetic resources for insect resistance by elucidating the biological function and resistance mechanisms of these new types of resistance genes. Our results have important scientific significance to breed broad-spectrum and durable insect-resistant rice varieties.

稻飞虱是一种破坏性极强的水稻害虫，通过刺吸水稻韧皮部汁液导致水稻减产甚至绝收，严重威胁水稻生产。随着水稻功能基因组学研究迅速发展，人们从野生稻和栽培稻中已经分离鉴定了一些重要的水稻抗飞虱基因，其编码产物主要分为两大类：定位于细胞质中的NB-LRR蛋白和定位于质膜的凝集素受体激酶。Bph6基因编码定位于胞泌复合体的新型抗虫蛋白，对褐飞虱和白背飞虱具有广谱抗性，除此之外，其他新类型的抗飞虱基因功能并不清楚。聚合不同类型的抗虫基因对于抗虫水稻的培育与分子设计具有重要的指导意义，因此，鉴定分离不同类型的抗虫基因并阐明其抗虫的机理是亟待解决的科学问题。本项目拟利用γ射线辐射诱变获得的水稻突变体材料，采用图位克隆的方法鉴定分离新型的水稻抗虫基因，并进一步解析其生物学功能和抗虫机制。该研究将提供更多种类的水稻抗虫资源，揭示新的抗虫机理与途径，对于培育广谱持久抗虫品种具有重要的科学意义。

稻飞虱是一种破坏性极强的水稻害虫，通过刺吸水稻韧皮部汁液导致水稻减产甚至绝收，严重威胁水稻生产。随着水稻功能基因组学研究迅速发展，人们从野生稻和栽培稻中已经分离鉴定了一些重要的水稻抗飞虱基因，但是人们对水稻抗飞虱的具体的分子机制却知之较少。我们发现一个抗褐飞虱的水稻突变体fy15，抗虫性鉴定发现该突变体材料对于水稻褐飞虱具有明显的抗性。利用图位克隆的方法，我们对于该突变中控制水稻抗性基因FY15进行定位。通过对该基因的生物学功能研究分析发现，该基因可能通过调控下游基因的表达水平参与水稻抗褐飞虱。该研究将提供更多种类的水稻抗虫资源，揭示新的抗虫机理与途径，对于培育广谱持久抗虫品种具有重要的科学意义。