形成杆状病毒多角体膜主要结构域的解析及其在抗紫外线方面的应用

苜蓿银纹夜蛾核型多角体病毒（AcMNPV）作为杀虫剂具有致病率高、宿主范围相对较宽、对非靶标生物安全等优点，但它对紫外线的敏感性极大地制约了其更大范围的应用。多角体膜是杆状病毒包涵体表面由多角体膜蛋白（PEP）和糖类组成的膜，对稳定包涵体的结构以及抵抗外界不良环境起重要作用。杆状病毒PEP由N端和C端保守区以及中间可变区组成，但这3个区域功能目前还不清楚。本项目通过酵母双杂交、免疫共沉淀、荧光共定位技术解析AcMNPV PEP的3个结构域在形成多角体膜过程中的作用，并通过构建含PEP不同截短片段的重组AcMNPV，揭示PEP形成多角体膜的最小功能域及其携带外源蛋白展示于包涵体表面的能力。在此基础上，构建PEP的功能域与抗紫外物质特异性结合肽融合的重组AcMNPV，通过展示于多角体膜上的多肽富集抗紫外物质，提高杆状病毒的抗紫外能力，为研发环境稳定的病毒杀虫剂提供基础。

Autographa californica multiple nucleopolyhedrovirus (AcMNPV) is known to be highly pathogenic for the several insect pests and safe for non-target organisms, whereas sensitiveness to UV radiation limits its application at a large scale. The polyhedron envelope, composed of carbohydrate and polyhedron envelope protein (PEP), is a major structure for the stability and persistence of baculovirus occlusion bodies (OBs). Baculovirus PEP contains the conserved N- and C-terminal regions and a middle-flexible region. In this project, we will reveal the roles of these regions in the formation of polyhedron envelope using yeast two-hybrid, Co-IP and immunofluorescence confocal microscopy. We will further identify the key domains which are capable of forming the intact polyhedron envelope and carrying exogenous proteins to surface of OBs by constructing a serial AcMNPV recombinants with different truncated fragments of PEP fused with the eGFP. Furthermore, we will construct AcMNPV recombinants which displayed nano-ZnO or melanin binding peptides on the surface of OBs. The anti-UV efficiency of these recombinants will be evaluated in the laboratory bioassays. These works will provide a new approach to protect the baculoviral insecticides against UV irradiation in the field conditions.