【摘要】 目的探讨广州地区婴幼儿腹泻中感染Noro病毒的基因型。方法用ClustalW比对GⅡ组Noro病毒后,设计处于ORF1与ORF2连接点两旁两对简并引物,进行巢式RT-PCR扩增出目标片段,克隆于T载体上,测定序列,对ORF1与ORF2连接点两旁序列和衣壳蛋白N/S区用ClustalW进行同源性分析,用phylip3·65软件、邻接法构建进化树。结果标本NVgz100、NVgz10成功扩增出ORF1与ORF2连接点两旁1208bp片段(相对于Hawaiivirus,U07611位置为4476-5683),包含ORF1的3′端RdRp的大部分基因和ORF2基因的5′端的S区。对标本NVgz100、NVgz10与另一实验NVgz01(DQ369797)的1208bp进行同源性分析发现,3份标本与GⅠ组同源性为58%~61%,与GⅡ组同源性为74%~92%;将这3份标本与GⅠ、GⅡ组构建进化树,可发现NVgz100、NVgz10和NVgz01与GⅡ组Bristol等病毒密切相关,将NVgz100、NVgz10和NVgz01的衣壳蛋白N/S区与GⅡ组各基因型进行同源性比较,发现3份标本与GⅡ-4基因型Camberwell、BristoltGrimsby同源性较高(92%~96%),与其他基因型同源性为70%~73%,以N/S区构建进化树可发现3份标本与Camberwell、Bristol、Grimsby、Lordsdale处于同一簇中。结论本实验结果表明Noro病毒株以GⅡ组为主,病毒流行的基因型为与Camberwell、Bristol、Grimsby和Lordsdale等密切相关的GⅡ-4基因型。更多还原

【Abstract】 Objective To investigate the genotype of Noro virus infection in infants with diarrhea in Guangzhou.Methods Primers were designed on the basis of the sequence of Hawaii virus after ClustalW alignment of six human Noro virus genomic sequences,and the fragment of ORF 1-ORF 2 junction was amplified by nest PCR. The PCR-products were cloned to T vector and sequenced,phylogenetic tree was constructed by the neighbor joining method in Phylip3.65.Results The amplified sequence of ORF 1/ORF 2 junction was 1 208 bp in length,corresponded to the regions located between nucleotides 4476 and 5683 in the Hawaii virus genome(GenBank accession number U07611).The sequence contained 3′-RNA polymerase sequence and N-terminus/shell domain in ORF 2 gene. The three ORF 1-ORF 2 fragments were compared with those of Noro virus in GenBank,revealed that the homology with genogroupⅡ ranged between 74%~92%,and genogroupI between 58%~61%.The N/S domains of three samples were analyzed by comparing the sequences of strains representing each genotype of GⅡ,the result revealed that the homology with GⅡ-4 ranged between 92%~96%.phylogenetic trees based on capsid N/S domain and ORF 1-ORF 2 junction sequence were constructed by the neighbor-joining method with Manchester strain as an outgroup,and found that the three samples were closer to GⅡ-4 stains than to other reference strains.Conclusions Noro virus strains infection in Guangzhou belonged to genogroupII.The predominant strains were identified as GⅡ-4 genotype.更多还原