GI型诺如病毒湖州株2008/Huzhou/N11进行全基因组序列测定与分析

Complete Genome Analysis of a Recombinant GI Norovirus Identified in Huzhou,China

为了对GI型诺如病毒湖州株2008/Huzhou/N11进行全基因组序列测定,了解其分子特征及基因类型。方法是根据GenBank上下载的GI型诺如病毒各基因型代表株保守序列设计特异性引物对2008/Huzhou/N11进行全基因组测序,并与GI型诺如病毒各基因型的原型株进行全序列的比对,使用MEGA 4.0软件绘制系统进化树。利用Simplot3.5.1软件进行相似性分析,对基因重组加以验证。结果表明,诺如病毒2008/Huzhou/N11基因组全长7 691bp,有3个开放阅读框（ORF）。ORF1长5 367bp（5～5 371nt）,ORF2长1 623bp（5 355～6 977nt）,ORF3长630bp（6 977～7 606nt）。RNA聚合酶区（4 320～5 091bp）系统进化分析显示2008/Huzhou/N11属于GI.2基因型,VP1区（5 355～6 977bp）和VP2区（6 977～7 606bp）的系统进化分析显示2008/Huzhou/N11属于GI.6基因型。进一步的Simplot分析提示2008/Huzhou/N11为GI.2/GI.6重组株,重组位点位于ORF1和ORF2重叠区的上游。本文确定了我国GI型诺如病毒湖州株2008/Huzhou/N11为GI.2/GI.6重组株,可为国内诺如病毒的遗传进化研究提供序列参考。

To study the genotype and genomic and molecular organization of a GI norovirus isolate from Huzhou,China,the genomic sequence of 2008/Huzhou/N11 was amplified by RT-PCR,then the PCR product was purified,sequenced,and input into phylogenetic and Simplot analyses.The complete genomic sequence of the 2008/Huzhou/N11 strain was 7691nucleotides（nt）long.It contained three open reading frames（ORFs）：ORF1,ORF2,and ORF3,with lengths of 5367,1623,and 630 nt,respectively.Phylogenetic analysis revealed that the RdRp region of 2008/Huzhou/N11 belonged to genotype GI.2,and the VP1 and VP2regions belonged to genotype GI.6.The SimPlot analysis indicated that potential recombination points in 2008/Huzhou/N11 were located upstream of the ORF1/ORF2 overlap.The complete genomic sequence of this recombinant GI.2/GI.6strain can serve as a reference sequence for the phylogenetic analysis of norovirus evolution.