State Key Laboratory for Infectious Disease Prevention and Control, Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 100052, PR China.
J Gen Virol. 2010 Nov;91(Pt 11):2836-45. doi: 10.1099/vir.0.024794-0. Epub 2010 Aug 11.
During an investigation of arboviruses in China, a novel dsRNA virus was isolated from adult female Armigeres subalbatus. Full genome sequence analysis showed the virus to be related to members of the family Totiviridae, and was therefore named 'Armigeres subalbatus totivirus' (AsTV). Transmission electron microscopy identified icosahedral, non-enveloped virus particles with a mean diameter of 40 nm. The AsTV genome is 7510 bp in length, with two ORFs. ORF1 (4443 nt) encodes the coat-protein and a dsRNA-binding domain (which may be involved in the evasion of 'gene silencing'), while ORF2 (2286 nt) encodes the viral RNA-dependent RNA polymerase (RdRp). The AsTV coat protein shows a higher level of amino acid identity with Drosophila totivirus (DTV, 52 %) than with infectious myonecrosis virus (IMNV, 29 %). Similarly, the RdRp shows higher identity levels with DTV (51 %) than with IMNV (44 %). Identity levels to other members of the family Totiviridae, in either the coat protein or the RdRp, ranged from 6 to 11 %. Based on a recent reassessment of the coding strategy used by IMNV, we suggest that an AsTV coat-RdRp fusion protein could be synthesized via a -1 frameshift. Elements favouring -1 frameshift such as 'slippery heptamers' and pseudonkots, were identified in the AsTV, DTV and IMNV genomes. AsTV was shown to grow in both mosquito and mammalian cells, suggesting that it is an arbovirus that can infect mammals.
在中国的虫媒病毒调查中,从成体雌性白纹伊蚊中分离到一种新型双链 RNA 病毒。全基因组序列分析显示,该病毒与 totiviridae 科的成员有关,因此被命名为“白纹伊蚊 totivirus”(AsTV)。透射电子显微镜鉴定出具有平均直径为 40nm 的二十面体、无包膜病毒粒子。AsTV 基因组长 7510bp,有两个 ORF。ORF1(4443nt)编码外壳蛋白和 dsRNA 结合域(可能参与逃避“基因沉默”),而 ORF2(2286nt)编码病毒 RNA 依赖性 RNA 聚合酶(RdRp)。AsTV 外壳蛋白的氨基酸同一性水平比传染性肌坏死病毒(IMNV,29%)更高,与果蝇 totivirus(DTV,52%)。同样,RdRp 与 DTV(51%)的同一性水平高于与 IMNV(44%)。与 totiviridae 科的其他成员相比,外壳蛋白或 RdRp 的同一性水平在 6%到 11%之间。基于对 IMNV 使用的编码策略的最新重新评估,我们建议 AsTV 外壳-RdRp 融合蛋白可以通过 -1 移码进行合成。在 AsTV、DTV 和 IMNV 基因组中鉴定到有利于 -1 移码的元件,如“滑七聚体”和假核。AsTV 被证明在蚊子和哺乳动物细胞中都能生长,表明它是一种可以感染哺乳动物的虫媒病毒。