State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China.
College of Life Sciences, Langfang Normal University, Langfang 065000, China; Laboratory of Phytopathology, University of Liège, Gembloux Agro-BioTech, Passage des déportés, 2, 5030 Gembloux, Belgium.
Virus Res. 2019 Oct 15;272:197651. doi: 10.1016/j.virusres.2019.197651. Epub 2019 Aug 10.
A novel iflavirus, tentatively named laodelphax striatellus iflavirus 1 (LsIV1), was identified in Laodelphax striatellus by total RNA-sequencing, and its genome sequence was confirmed by Sanger sequencing. The complete genome consisted of 10,831 nucleotides with a polyA tail and included one open reading frame, encoding a 361.7-kD polyprotein. Conserved motifs for structural proteins, helicase, protease, and RNA-dependent RNA polymerase were identified by aligning the deduced amino acid sequence of LsIV1 with several other iflaviruses. The genome has the highest identity with another planthopper iflavirus, nilaparvata lugens honeydew virus-3 (39.7%), under the species demarcation threshold (90%). Results of the identities and phylogenetic analysis based on the deduced amino acid sequences of the complete polyprotein and helicase of LsIV1 and other iflaviruses, indicated it is a new species belonging to the family Iflaviridae. Furthermore, we did not observe any differences of biological characterizations like development and reproduction between viruliferous and virus-free SBPH. Meanwhile, we found that female could transmit LsIV1 with higher transmission efficiency.
通过全 RNA 测序，在褐飞虱中鉴定出一种新型的乙型昆虫病毒，暂定名为直纹稻虱乙型昆虫病毒 1（LsIV1），并通过 Sanger 测序确定了其基因组序列。完整的基因组由 10831 个核苷酸组成，带有 polyA 尾巴，包含一个开放阅读框，编码一个 361.7kD 的多聚蛋白。通过将 LsIV1 的推导氨基酸序列与其他几种乙型昆虫病毒进行比对，鉴定出了结构蛋白、解旋酶、蛋白酶和 RNA 依赖性 RNA 聚合酶的保守基序。基因组与另一种粉虱乙型昆虫病毒——褐飞虱蜜露病毒 3（39.7%）在种划分阈值（90%）下具有最高的同一性。基于 LsIV1 的完整多聚蛋白和解旋酶以及其他乙型昆虫病毒的推导氨基酸序列的同一性和系统发育分析结果表明，它是一种属于乙型昆虫病毒科的新物种。此外，我们没有观察到带毒和不带毒的 SBPH 在发育和繁殖等生物学特征上有任何差异。同时，我们发现雌性能够以更高的传播效率传播 LsIV1。
