棉铃虫Transib转座子沉默相关piRNA克隆及其功能研究

Cotton bollworm, one of the economically important pests world wide, become more destructive due to their different levels of resistance to chemical insecticides and Bt. Transgenic insect dominant lethal or sterile insect technology based DNA transposon is an important strategy for pest control. It has been transferred from the research laboratory to the field for assessment. Transib can be used as insect genetic transformation tool with a low efficiency. The preliminary results show that the 30bp cis element locatedin Transib ORF cause Transib mRNA polyadenylated at the proximal poly(A) site and transcribed into the non-stop mRNA. Northern blot indicated that a similar piRNA (mmu_piR_001969-like piRNA) which share high homologity with the cis-element reverse complementary sequence exist in bollworm.The project specific aim is 1) clone the piRNA and testify its function in Transib silencing; 2) evaluate the Transib's transposition activity after disrupting the piRNA target site. The project will enrich the knowledge of piRNA-transposons silence. The stuy will provide a theoretical basis for the development of efficient genetic transformation system based on Transib and the use of transgenic insect dominant lethal or sterile technology for control cotton bollworm.

棉铃虫是一种世界性农业害虫，其对化学杀虫剂和Bt已产生了不同水平的抗性。 基于DNA转座子的转基因昆虫显性致死或不育技术已经成为害虫防治的一项重要策略，并从实验室研究转入田间早期评估。Transib可以作为昆虫遗传转化工具，但其效率较低。前期研究表明，Transib ORF中的30bp顺式元件导致Transib mRNA加尾在近端poly(A)位点而转录成non-stop mRNA；棉铃虫中存在着与mmu piR 001969-like piRNA类似的piRNA，且与顺式元件的反向互补序列高度同源。本项目拟通过piRNA克隆和功能验证明确其对Transib的沉默功能，并阐明干扰piRNA作用靶点对Transib转座活性的影响。该研究将丰富对piRNA沉默转座子的认识，可为设计高效Transib遗传转化体系及利用基于该转化系统的转基因昆虫显性致死或不育技术防治棉铃虫奠定理论基础。