Department of Medical Entomology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan.
Virus Res. 2011 Jan;155(1):147-55. doi: 10.1016/j.virusres.2010.09.013. Epub 2010 Sep 25.
Two infectious agents were isolated from Culex species mosquitoes in Japan and were identified as distinct strains of a new RNA virus by a method for sequence-independent amplification of viral nucleic acids. The virus designated Omono River virus (OMRV) replicated in mosquito cells in which it produced a severe cytopathic effect. Icosahedral virus particles of approximately 40 nm in diameter were detected in the cytoplasm of infected cells. The OMRV genome was observed to consist of a nonsegmented, 7.6-kb double-stranded RNA (dsRNA) and contain two overlapping open reading frames (ORFs), namely ORF1 and ORF2. ORF1 was found to encode a putative dsRNA-binding protein, a major capsid protein, and other putative proteins, which might be generated by co- and/or post-translational processing of the ORF1 polyprotein precursor, and ORF2 was found to encode a putative RNA-dependent RNA polymerase (RdRp), which could be translated as a fusion with the ORF1 product by a -1 ribosomal frameshift. Phylogenetic analysis based on RdRp revealed that OMRV is closely related to penaeid shrimp infectious myonecrosis virus and Drosophila totivirus, which are tentatively assigned to the family Totiviridae. These results indicated that OMRV is a new member of the family of nonsegmented dsRNA viruses infecting arthropod hosts, but not fungal or protozoan hosts.
两种感染性因子从日本库蚊中分离得到，并通过一种非序列依赖性扩增病毒核酸的方法鉴定为一种新的 RNA 病毒的不同株系。这种被命名为大物川病毒（OMRV）的病毒可以在蚊细胞中复制，在其中产生严重的细胞病变效应。在感染细胞的细胞质中检测到直径约为 40nm 的二十面体病毒粒子。观察到 OMRV 基因组由一个非节段的 7.6kb 双链 RNA（dsRNA）组成，并包含两个重叠的开放阅读框（ORF），即 ORF1 和 ORF2。发现 ORF1 编码一个假定的 dsRNA 结合蛋白、一个主要衣壳蛋白和其他假定的蛋白，这些蛋白可能通过 ORF1 多蛋白前体的共翻译和/或翻译后加工产生，而 ORF2 编码一个假定的 RNA 依赖性 RNA 聚合酶（RdRp），它可以通过 ORF1 产物的 -1 核糖体移码进行翻译融合。基于 RdRp 的系统发育分析表明，OMRV 与对虾传染性肌肉坏死病毒和果蝇 totivirus 密切相关，后者被暂时归入 totiviridae 科。这些结果表明，OMRV 是感染节肢动物宿主的非节段 dsRNA 病毒家族的一个新成员，但不是真菌或原生动物宿主。
