Yang Du-Juan, Li Ming-Hua, Fu Shi-Hong, Zhang Hai-Lin, Liang Guo-Dong
Yunnan Institute of Endemic Disease Control and Prevention, Dali 671000, China.
Bing Du Xue Bao. 2011 Nov;27(6):571-9.
To conduct sequencing of full-length genomes of two Japanese encephalitis virus strains (JEV) newly isolated in 2009 in China and analyze the characteristics of complete nucleotide sequences. The complete genomic sequences were obtained by RT-PCR and sequencing directly. Bioinformatics was used to analyze the nucleic acid data, deduced amino acid sequence and phylogenetic trees. The result of sequence analysis showed that the genomes of YN0911 and YN0967 strains were both 10965nt in length, which coded 3432 amino acid polyprotein. The homology of genome ranged from 83.3% to 98.9% in nt and from 94.8% to 99.7% in aa, respectively, when compared with selected JEV strains in GenBank. There were 13 amino acid divergences which were not the key virulence sites in E protein when compared with vaccine strain SA14-14-2. There were 11nt deletions in the 3' UTR region. Phylogenetic analyses based on C/ PrM, E gene and full-length genome all showed that YN0911 and YN0967 strains belonged to genotype I. The result also showed that two new JEVs had close phylogenetic relationship with the strains from Viet Nam, Sichuan Province, Guizhou Province, Guangxi Province, China. This study indicated that JEV strains newly isolated in 2009 in China were the members of JEV genotype I. The key virulence sites in E protein did not change.
对2009年在中国新分离的两株日本脑炎病毒（JEV）进行全基因组测序，并分析其完整核苷酸序列的特征。通过RT-PCR和直接测序获得完整的基因组序列。运用生物信息学分析核酸数据、推导的氨基酸序列和系统发育树。序列分析结果显示，YN0911和YN0967株的基因组长度均为10965nt，编码3432个氨基酸的多聚蛋白。与GenBank中选定的JEV株相比，基因组的核苷酸同源性在83.3%至98.9%之间，氨基酸同源性在94.8%至99.7%之间。与疫苗株SA14-14-2相比，E蛋白中有13个氨基酸差异位点，并非关键毒力位点。3'UTR区域有11个核苷酸缺失。基于C/PrM、E基因和全基因组的系统发育分析均表明，YN0911和YN0967株属于基因型I。结果还表明，这两株新的JEV与来自越南以及中国四川省、贵州省、广西壮族自治区的毒株具有密切的系统发育关系。本研究表明，2009年在中国新分离的JEV株是JEV基因型I的成员。E蛋白中的关键毒力位点未发生变化。
