Wang Luan, Wang Shuangchao, Yang Xiufen, Zeng Hongmei, Qiu Dewen, Guo Lihua
State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China.
Arch Virol. 2017 Jul;162(7):2119-2124. doi: 10.1007/s00705-017-3317-1. Epub 2017 Mar 15.
The complete nucleotide sequence of a double-stranded RNA (dsRNA) mycovirus, Fusarium graminearum dsRNA virus 5 (FgV5), was identified and characterized. The FgV5 genome comprises two dsRNA genome segments of 2030 bp and 1740 bp. FgV5 dsRNA1 contains a single open reading frame (ORF1), which is predicted to encode a protein of 613 amino acids (aa) with a molecular mass of 70.4 kDa and has a conserved RNA-dependent RNA polymerase (RdRp) motif. FgV5 dsRNA2 is predicted to contain two discontinuous ORFs (ORF2 and ORF3) that code for products of unknown function. Sequence comparisons showed that FgV5 has the highest aa sequence identities to Fusarium graminearum virus 4 (FgV4) (83.01% for ORF1, 78.70% for ORF2, and 76.27% for ORF3), suggesting that FgV5 and FgV4 should be regarded as members of different species. Phylogenetic analysis indicated that FgV5 belongs to a taxonomically unassigned dsRNA mycovirus group that is related to the families Amalgaviridae and Partitiviridae. Here, we propose that FgV5 and related viruses are members of a yet to be named and formally recognized new family.
鉴定并表征了一种双链RNA（dsRNA）真菌病毒——禾谷镰刀菌dsRNA病毒5（FgV5）的完整核苷酸序列。FgV5基因组由两个分别为2030 bp和1740 bp的dsRNA基因组片段组成。FgV5 dsRNA1包含一个单一的开放阅读框（ORF1），预计编码一个由613个氨基酸（aa）组成、分子量为70.4 kDa的蛋白质，并且具有保守的RNA依赖性RNA聚合酶（RdRp）基序。FgV5 dsRNA2预计包含两个不连续的开放阅读框（ORF2和ORF3），其编码功能未知的产物。序列比较表明，FgV5与禾谷镰刀菌病毒4（FgV4）具有最高的氨基酸序列同一性（ORF1为83.01%，ORF2为78.70%，ORF3为76.27%），这表明FgV5和FgV4应被视为不同的病毒种。系统发育分析表明，FgV5属于一个分类学上未归类的dsRNA真菌病毒组，与融合病毒科和分体病毒科相关。在此，我们提议FgV5及相关病毒是一个尚未命名和正式认可的新科的成员。
