Gupta Tania, Ito Katsuhiko, Kadono-Okuda Keiko, Murthy Geetha N, Gowri E Vijaya, Ponnuvel Kangayam M
Seribiotech Research Laboratory, Carmelaram-Post, Kodathi, Bangalore, 560035, India.
Laboratory of Sericultural Science, Department of Science of Biological Production, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu, Tokyo, 183-8509, Japan.
Arch Virol. 2018 Jan;163(1):125-134. doi: 10.1007/s00705-017-3584-x. Epub 2017 Oct 13.
The bipartite genome of an Indian isolate of Bombyx mori bidensovirus (BmBDV), one of the causative agents of the fatal silkworm disease 'Flacherie', was cloned and completely sequenced. Nucleotide sequence analysis of this Indian isolate of BmBDV revealed two viral DNA segments, VD1 and VD2 as well as a DNA polymerase motif which supports its taxonomical status as the type species of a new family of Bidnaviridae. The Indian isolate of BmBDV was found to have a total of six putative ORFs four of which were located on the VD1 with the other two being on the VD2 DNA segment. The VD1 DNA segment was found to code for three non-structural proteins including a viral DNA polymerase as well as one structural protein, while the VD2 DNA segment was found to code for one structural and one non-structural protein, similar to that of the Japanese and Zhenjiang isolates of BmBDV. A BmBDV ORF expression study was done through real time qPCR wherein the VD2 ORF 1 and 2 showed the maximum transcript levels. This is the first report of the genome characterization of an Indian isolate of BmBDV, infecting silkworm B. mori.
家蚕双顺反子病毒（BmBDV）印度分离株的二分基因组是致命家蚕疾病“空头病”的病原体之一，已被克隆并完成全序列测定。对该印度BmBDV分离株的核苷酸序列分析揭示了两个病毒DNA片段，即VD1和VD2，以及一个DNA聚合酶基序，这支持了其作为双顺反子病毒科一个新属的模式种的分类地位。发现印度BmBDV分离株共有六个推定的开放阅读框（ORF），其中四个位于VD1上，另外两个位于VD2 DNA片段上。发现VD1 DNA片段编码三种非结构蛋白，包括一种病毒DNA聚合酶以及一种结构蛋白，而VD2 DNA片段编码一种结构蛋白和一种非结构蛋白，这与日本和镇江的BmBDV分离株相似。通过实时定量PCR进行了BmBDV ORF表达研究，其中VD2的ORF 1和2显示出最高转录水平。这是关于感染家蚕的印度BmBDV分离株基因组特征的首次报道。
