葡萄蚕豆萎蔫病毒中国分离物基因组全长序列分析

 葡萄蚕豆萎蔫病毒(grapevine fabavirus,GFabV)是近年报道的葡萄新病毒,与葡萄褪绿斑驳、皱缩等症状发生相关,严重影响葡萄长势。本研究采用小RNA测序结合Sanger测序方法分别对表现褪绿斑驳的‘贝达’和无症状的‘赤霞珠’葡萄中的GFabV分离物进行基因组全长序列测定,获得了GFabV分离物LN_BETA2和LN_CXZ的基因组全长序列,其RNA1基因组全长分别为5 824 bp和5 823 bp,RNA2基因组全长分别为3 132 bp和3 135 bp。LN_BETA2与LN_CXZ的RNA1编码的多聚蛋白核苷酸序列之间的同源性为81.7%,与其他GFabV分离物多聚蛋白核苷酸同源性分别为73.4%~99.5%和73.5%~82.5%;LN_BETA2和LN_CXZ的RNA2编码的多聚蛋白核苷酸同源性为83.8%,与其他GFabV分离物多聚蛋白核苷酸同源性为75.0%~83.3%和68.2%~98.6%。系统进化树分析结果显示,在RNA1基因组中,LN_BETA2划分在组3,LN_CXZ形成单独的分支。RNA2基因组中,LN_BETA2和LN_CXZ分别划分在组3和组5中。本研究首次报道了GFabV中国分离物基因组全长序列,可为今后GFabV生物学特性及致病性研究提供工作基础。

Sequence analysis of complete genome of two grapevine fabavirus isolates from China

Grapevine fabavirus (GFabV) was recently reported as a new virus infecting grapevine. GFabV was associated with chlorotic mottling and deformation symptoms and seriously affected the vigor of grapevine. In this study, the complete genomic sequences of GFabV isolates from chlorotic mottled‘BETA’ and asymptomatic ‘Cabernet Sauvignon’, were determined by small RNA sequencing and conventional Sanger sequencing. The full-length genome sequences of the GFabV isolates LN_BETA2 and LN_CXZ were obtained. The full-length RNA1 genome was 5 824 and 5 823 bp, respectively, and the full-length RNA2 genome was 3 132 and 3 135 bp, respectively. The Polyprotein nucleotide similarity of RNA1 of LN_BETA2 and LN_CXZ was 81.7%, and that of the two isolates and other GFabV isolates was 73.4%-99.5% and 73.5%-82.5%, respectively.The Polyprotein nucleotide similarity of RNA2 of LN_BETA2 and LN_CXZ was 83.8%, and that of they and other GFabV isolates was 75.0%-83.3% and 68.2%-98.6%, respectively.Phylogenetic analysis showed that LN_BETA2 is divided into group 3, and LN_CXZ forms a separate subbranch in the RNA1 genome. In the RNA2 genome, LN_BETA2 and LN_CXZ are divided into group 3 and group 5 respectively. This study reported for the first time the full-length genome sequence of a Chinese isolate of GFabV, which can provide a work foundation for future research on the biological characteristics and pathogenicity of GFabV.