深入挖掘潜在的高致病性病原微生物资源是当前害虫生物防治发展的重大需求之一。本项目以分离自我国本土的高致病性烟芽夜蛾囊泡病毒3h株（HvAV-3h）为研究对象，利用流式细胞仪检测HvAV-3h感染所致的甜菜夜蛾脂肪体细胞系（SeFB）细胞周期进程的变化；基于转录组数据对甜菜夜蛾编码的细胞周期蛋白进行表达差异分析，结合RNA干扰技术对不同细胞周期蛋白的功能进行验证；对起关键作用的细胞周期蛋白基因进行克隆、表达、制备抗体，通过免疫荧光观察明确关键细胞周期蛋白的表达时空。同时，对HvAV-3h编码的早期表达蛋白进行筛选，挑选对宿主细胞周期具有显著影响的早期表达蛋白，深入研究其与宿主细胞间的互作关系，最终明确HvAV-3h感染对宿主细胞周期影响的分子机制。本项目研究结果将为阐明HvAV-3h感染导致“急性致病”的分子致病机制奠定基础，进一步为HvAV-3h在害虫防控实践中的推广应用提供科学依据。

To discover and develop any potential efficient pathogenic microorganisms as biological-pesticide is one of the most urgent requirement in insect pest bio-control. As the first reported ascovirus isolated from China, the high virulent strain Heliothis virescens ascovirus 3h (HvAV-3h) would be studied in this project. The effects of HvAV-3h infection on the host cell cycle (Spodoptera exigua fat body cell, SeFB) will be detected by flow cytometry. The data collected from transcriptome would be used to select cyclins encoded by Spodoptera exigua, and the RNAi will be performed to validate the function of those selected cyclins. The key cyclins would be cloned and expressed to prepare polyclonal antibody, and immunofluorescence observation will be performed to detect the key cyclins’ expression pattern. Several early proteins encoded by HvAV-3h would be selected and used to test the interaction with cyclins in the further experiments. At last, the mechanism of host cell cycle alteration by the infection of HvAV-3h would be declined. All the results in this study will lay the foundation for elucidating the specific “acute pathogenicity” mechanism of HvAV-3h, and provide scientific basis for the popularization and application of pest biological control.