昆虫基因组中存在着大量的转座子序列，其中一些在宿主的适应性进化中起到重要作用，关于这些功能转座子作用机制的研究较少。我们前期在黑腹果蝇的自然种群中发现一个天然转座子Doc1420与果蝇的抗病毒能力显著相关。进一步研究发现Doc1420插入果蝇基因CHK domain ov1（CHKov1）的编码区，并与部分基因序列共同形成CHKov1-Doc1420嵌合RNA。本项目将围绕嵌合RNA影响果蝇抗病毒能力的机制展开研究。首先利用分子生物学方法研究嵌合RNA的功能及其与病毒蛋白的互作；进而通过比较转录组筛选与Doc1420插入相关的差异表达基因，利用基因沉默和基因敲除研究候选基因的功能及其与嵌合RNA的互作关系。研究结果将有助于揭示功能转座子的作用机理以及新的抗病毒免疫机制，为防治经济昆虫病毒病、阻断虫媒病毒传播及开发病毒杀虫剂提供新的靶标和思路。

Insect genomes contain large numbers of transposable elements (TEs) and we’ve just started to understand their roles in host adaptive evolution. There is a lack of studies on the mechanisms of these functional TEs. In our previous study of natural populations of Drosophila melanogaster, a Doc1420 element was found associated with an increase in antiviral resistance in flies. Further experiments showed that Doc1420 inserted into the coding region of a fly gene, CHK domain ov1 (CHKov1), and formed a chimeric RNA with partial sequence of the gene. In this project, we will explore the function of CHKov1-Doc1420 chimeric RNA and the antiviral pathway it’s involved. We will use molecular approaches to study the function of the chimeric RNA and its interactions with viral proteins. Meanwhile, we will apply transcriptome sequencing, RNAi and gene knock-out to identify immune genes that interact with the chimeric RNA. This study would help us understand the function of CHKov1-Doc1420 chimeric RNA and reveals new antiviral immune mechanism. In addition, it will provide new targets and strategies for managing insect viral diseases, disrupting insect transmission of viruses as well as for developing new viral pesticides.