Analyses of molecular mechanism for the host specificity determination in nucleopolyhedroviruses

从田间采集的斜纹夜蛾(SpltMNPV)和甜菜夜蛾(SeMNPV)幼虫未克隆群体中分离到多个核型多角体病毒(NPV)克隆分离物。根据病毒复制、结构蛋白合成、芽胞病毒产量、多角体合成、多角体形成、多角体形成等7种不同细胞系的生物学特性，研究了这些NPV毒株与褐斑潜蝇、家蚕、白僵菌和白僵菌7个不同细胞系的生物学特性。研究发现，这些NPV分离物中的每一个都与各自的细胞系建立了特定的相互作用。这些相互作用包括不同类型的流产感染和细胞凋亡以及生殖性感染。为了深入了解NPV宿主特异性决定的分子机制，我们鉴定并鉴定了多种病毒基因，包括gp64、即早基因-1、极晚期因子-1、凋亡抑制因子、p35、同源重复区域、增殖细胞核抗原和蜕皮激素UDP-葡萄糖基转移酶。功能分析表明，部分病毒基因与NPV感染细胞的感染性流产和细胞凋亡有关。

A number of clonal isolates of nucleopolyhedrovirus (NPV) were derived from uncloned population from the larvae of Spodoptera litura (SpltMNPV) and S. exigua (SeMNPV) collected in the field. These NPV isolates together with NPVs from Autographa californica (AcMNPV), Bombyx mori (BmNPV), Hyphantria cunea (HycuNPV), Orgyia pseudotsugata (OpMNPV), and Lymantria dispar (LdMNPV) were characterized for their biological properties in seven different cell lines derived from S. frugiperda (Sf9), S. litura (SpLi), S. littoralis (CLS-79), S. exigua (Se301), L dispar (Ld652Y), Spilosoma imparilis (Splm), and B. mori (BmN-4), On the basis of the data oh viral DNA replication, viral structural protein synthesis, budded virion yield, polyhedrin synthesis, and polyhedral formation, it was found that each of these NPV isolates established specific interactions with the respective cell lines. These interactions included varying types of abortive infection and apoptosis as well as productive infection. To provide insights into the molecular mechanisms underlying the host specificity determination of NPVs, a number viral genes including gp64, ie-1 (immediate early gene-1), vlf-1(very late factor-1), iaps (inhibitors of apoptosis), p35, hrs (homologous repeated regions), pcna (proliferating cell nuclear antigen), and egt (ecdysone UDP-glucosyltransterase) were identified and characterized. Functional analyzes suggested that some of these viral genes were relevant to the infectious abortion and apoptosis in the cells infected with NPVs.