西花蓟马产雄孤雌生殖性别决定模式及分子机制

Our project aims at western flower thrips, Frankliniella occidentalis (Pergande), which is an invasive pest and increasingly seriously dangerous in China, and focuses on arrhenotoky that diractly affect the establishemnt and development of western flower thrips, and the conduct intesive research on the sex determination mechanism of arrhenotoky. We are ready to establish an “inbreeding cross” population （always sibling cross）derived from mother-son backcross （M-S cross）as the carrier researched in our project to explore the sex determination mechanism of western flower thrips. The aim of this peoject is to provide the important theoretical foundation for enriching the sex determinational theory and exploring the invasion mechinism and looking for new method to control of of western flower thrips. We would like to systematically research the sex determination mechanism of arrhenotoky of western flower thrips using establishment of “inbreeding cross” population. We then plan to explore the variation of ploidy and genotype, analyze the genetic structure in the arrhenotokous inbreeding cross population, and try to determine the sex determined mechanism of western flower thrips by karyotype analysis and microsatellite analysis. We also look forward to obtain and characterize the protein differentially expressing in the parthenogenetic population of western flower thrips by 2D gel electrophoresis and mass spectrometry for protein. Several genes possibly related to sex determination hope to be cloned by RT-PCR and RACE, then will be analyzed by bioinformatics. Finally, the cloned genes will be done the functinal verification using RNAi. All the results from our project will theoretically enrich and perfect the gennetic evolution research of the sex determination mechanism of arrhenotoky and extremely contribute to control the danger and invasion of western flower thrips in practice.

本项目以目前在我国危害日益严重的入侵性害虫西花蓟马为研究对象，围绕产雄孤雌生殖直接影响西花蓟马种群建立与发展的科学问题，深入研究西花蓟马产雄孤雌生殖性别决定机制。本研究拟通过采用建立近亲繁殖种群的方式，采用种群参数和染色体核型分析技术，解析西花蓟马产雄孤雌生殖的性别决定模式；同时借助微卫星分析技术，分析西花蓟马孤雌生殖种群的遗传构成；进而应用二维凝胶电泳和质谱分析技术，鉴定并分析西花蓟马孤雌生殖种群差异表达蛋白，运用RT-PCR 及RACE 技术，克隆可能与性别决定和孤雌生殖有关的差异蛋白基因并进行相关生物信息学分析；最后利用RNAi技术，对克隆出的相关基因进行功能验证，从而深入揭示西花蓟马产雄孤雌生殖性别决定的分子机制。研究结果将在理论上丰富产雄孤雌生殖性别决定遗传进化理论，在实践上为探寻针对该类害虫的遗传控制技术提供新思路。

西花蓟马Frankliniella occidentalis是我国一种危害日益严重的重大入侵性害虫，其采用产雄孤雌和两性生殖的方式繁殖后代，单倍二倍体的性别决定方式和高繁殖力使其种群的抗逆基因在种群中迅速增加，从而提高整个种群的适应度。围绕产雄孤雌生殖直接影响西花蓟马种群建立与发展的科学问题，深入研究西花蓟马产雄孤雌生殖性别决定机制，不仅对于防治西花蓟马而且对于其他一大批采取相似繁殖策略的重要害虫具有重要的研究价值。本项目在国家自然科学基金委的资助下，通过三年的研究取得了非常有意义的结果：实验条件下进一步明确了单头雌性西花蓟马建立种群的过程，成功构建了西花蓟马产雄孤雌生殖近亲繁殖种群，通过两性生命表系统分析了西花蓟马产雄孤雌生殖近亲繁殖种群动态。构建了西花蓟马两性鉴定SSR分子标记体系，通过转录组学的方法全面分析了西花蓟马两性之间的差异基因，为下一步寻找西花蓟马性别决定关键基因奠定了坚实的基础。此外，借助本项目的资助，我们还开发了西花蓟马原代培养技术。以上结果为今后明确西花蓟马性别决定机制，进而建立生殖调控防治技术体系提供了充分的理论依据。