增强鳞翅目昆虫家蚕RNAi效率的研究

RNA interference (RNAi) is a powerful reverse genetic tool in functional genomics study. However, the efficiency shows high diversity in different insect species. The silkworm, Bombyx mori, is the lepidopteran model insect, which shows few successful RNAi experiment and little understanding about the RNAi mechanism. This hampered the application of RNAi strategy in insect genomic study and pest management. In the current study, we plan to construct a RNAi sensitive transgenic silkworm, which contains multiple RNAi enhancer. Based on our previous study, the first step is investigating the RNAi efficiency between different developmental stages; the second step is screening the RNAi core factors in silkworm BmN cell line and embryos; and in the last step, we will over-express one or several RNAi core factors to improve the RNAi efficiency. Our work will elucidate the mechanism of lepidopteran RNAi and construct RNAi enhanced silkworm line which contains multiple factors.

RNA干涉（RNAi）是功能基因组学研究重要的反向遗传学工具，其效率在昆虫类群中呈现高度的差异性。家蚕是鳞翅目代表性模式昆虫，除了少数成功的案例外，RNAi效果都不理想，对其作用机制的了解更是空白，这很大程度上限制了RNAi在鳞翅目中的应用和发展。本项研究以家蚕为研究材料，一方面利用构建的红色荧光蛋白转基因家蚕，深入分析不同发育时期的RNAi效率差异，另一方面利用家蚕细胞系和胚胎，筛选家蚕RNAi关键基因。在此基础上，借助于家蚕转基因技术，构建含有多元增强因子的转基因家蚕品系，获得具有高效RNAi应答能力的转基因家蚕系统。该项研究将为开发安全高效的新抗虫技术和益虫的利用提供理论依据。

RNA干扰（RNAi）是生物体防御外界入侵病毒的重要方式之一，同时也是进行功能基因研究的重要手段。昆虫RNAi效率差异很大，其中鳞翅目昆虫RNAi效率很低。该项目研究旨在增强鳞翅目昆虫幼虫期RNAi效率。基于RNAi通路，我们筛选获得了两个家蚕RNAi通路关键基因，Ago2和Dicer2。利用转基因技技术分别过表达这两个基因，并且证实这两个转基因家蚕品系幼虫期RNAi效率有所增强。同时，通过将两个转基因品系杂交，获得共表达BmAgo2和BmDicer2的家蚕品系，其RNAi效率有进一步的增强。此项研究为鳞翅目昆虫的功能基因研究提供了实践基础。