State Key Laboratory of Virology and China Center for Virus Culture Collection, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China.
Canadian Forest Service, Great Lakes Forestry Centre, Sault Ste Marie, ON, P6A 2E5, Canada.
Virol Sin. 2018 Aug;33(4):359-368. doi: 10.1007/s12250-018-0047-9. Epub 2018 Aug 28.
The Cyclophragma undans nucleopolyhedrovirus (CyunNPV), a potential pest control agent, was isolated from Cyclophragma undans (Lepidoptera: Lasiocampidae), an important forest pest. In the present study, we performed detailed genome analysis of CyunNPV and compared its genome to those of other Group I alphabaculoviruses. Sequencing of the CyunNPV genome using the Roche 454 sequencing system generated 142,900 bp with a G + C content of 45%. Genome analysis predicted a total of 147 hypothetical open reading frames comprising 38 baculoviral core genes, 24 lepidopteran baculovirus conserved genes, nine Group I Alphabaculovirus conserved genes, 71 common genes, and five genes that are unique to CyunNPV. In addition, the genome contains 13 homologous repeated sequences (hrs). Phylogenetic analysis groups CyunNPV under a distinct branch within clade "a" of Group I in the genus Alphabaculovirus. Unlike other members of Group I, CyunNPV harbors only nine of the 11 genes previously determined to be specific to Group I viruses. Furthermore, the CyunNPV lacks the tyrosine phosphatase gene and the ac30 gene. The CyunNPV F-like protein contains two insertions of continuous polar amino acids, one at the conventional fusion peptide and a second insertion at the pre-transmembrane domain. The insertions are likely to affect the fusion function and suggest an evolutionary process that led to inactivation of the F-like protein. The above findings imply that CyunNPV is a distinct species under Group I Alphabaculovirus.
波纹环棱螺核多角体病毒（CyunNPV）是一种潜在的害虫控制剂，从重要的森林害虫波纹环棱螺（鳞翅目：天蚕蛾科）中分离出来。在本研究中，我们对 CyunNPV 进行了详细的基因组分析，并将其基因组与其他 I 组α杆状病毒进行了比较。使用 Roche 454 测序系统对 CyunNPV 基因组进行测序，共生成 142900bp，G+C 含量为 45%。基因组分析预测总共存在 147 个假定的开放阅读框，包含 38 个杆状病毒核心基因、24 个鳞翅目杆状病毒保守基因、9 个 I 组α杆状病毒保守基因、71 个共同基因和 5 个 CyunNPV 特有的基因。此外，基因组还包含 13 个同源重复序列（hrs）。系统发育分析将 CyunNPV 归为杆状病毒属 I 组“a”分支下的一个独特分支。与其他 I 组成员不同，CyunNPV 仅携带 11 个先前确定为 I 组病毒特有的基因中的 9 个。此外，CyunNPV 缺乏酪氨酸磷酸酶基因和 ac30 基因。CyunNPV F 样蛋白包含两个连续极性氨基酸的插入，一个在常规融合肽处，另一个在跨膜前域处。这些插入可能会影响融合功能，并表明导致 F 样蛋白失活的进化过程。上述发现表明，CyunNPV 是 I 组α杆状病毒中的一个独特物种。
