诺如病毒广州株全基因组序列测定及分析

The complete getmmic sequence analysis of human Norovirus NVgz01 strain in Guangzhou

目的 探讨广州地区儿童感染的诺如病毒基因组分子结构特点和基因组类型。方法 参考GenBank上的诺如病毒MD145-12基因组设计分段扩增引物，进行RT-PCR分段扩增诺如病毒基因组，克隆于T载体上，测定序列，用Clustal W／X、DNAStar、RAT（recombination analysis tool）等软件分析基因组序列。结果 诺如病毒NVgz01全基因组为7558bp，提交到C,enBank上的序列号为DQ369797，3’端非编码区末端长45bp，病毒基因组有3个开放阅读框（ORF），ORF1长5100bp（5～5104nt），ORF2基因长1623bp，位于基因组中5085～6707nt之间，ORF3基因长807bp（6707～7513nt），其中ORF1、ORF2两基因有19个核苷酸的重叠区；NVgz01全基因组核苷酸序列与GenBank上诺如GI组Norwalk68、Southampto、BS5、Chiba、WUG1的同源相似性在43％～44％之间，与GⅡ组MD145、Farmington Hills、B4S5、Hawaii、Lordsdale、SaitamaU1、Mc37同源相似性在76％～90％之间。NVgz01的ORF1与Mc37核苷酸序列同源性为94％，但ORF2与Mc37的同源性只有65％；NVgz01的ORF2与Fannillgton Hills（AY502023）同源性为最高（94％），ORF1的同源性为88％。结论广州地区儿童腹泻感染的诺如病毒NVgz01株全基因组序列为7558bp，GenBank序列号为DQ369797，NVgz01与诺如病毒的GⅡ组同源性较高，确认NVgz01株属于诺如病毒GⅡ组；根据ORF1、ORF2的同源性差异和RAT程序分析初步认为NVgz01可能是重组病毒。

Objective To study the genomic molecular organization and genogroup of human Nowvirus infected infants in Guangzhou of China.Methods Primers were designed on the basis of the genomic sequence of Norovirus in the GenBank,and the Norovirus genome was amplified by RT-PCR. The PCR-pmducts were cloned to T vector and sequenced,the gerlomic nucleofide sequences were analyzed with the programs CLUSTAL W/X, DNAStar and recombination analysis tool （RAT）.Results The NVgz01 strain genome is 7558 bp in length and encodes three open reading frames（ORF）.The length of ORF1 is 5100 bp（5-5104 nt）,ORF2 is 1623 bp in length （5085-6707 nt） and overlaps ORF1 by 19 nucleotides, ORF3 is about 807 bp long（6707-7513 nt）.The 3＇NTR is 45 nucleotides long.Comparison of genomic sequences between NVgz01 strain and Nomvirus in GenBank revealed that the homology with genogroup Ⅱ ranges between 76%-90%, and that with genogroup Ⅰ between 43%-44%. The ORF1 region shared 94% and 88% identity with Mc37 and Fannington Hills, respectively;the capsid region （ORF2） shared 65% and 94% identity with Mc37 and Farmington Hills strains,respectively.Conclusion The complete nucleofide sequence of Nomvims NVgz01 strain detected from Guangzhou in China is 7558 bp in length, GenBank accession No. is DQ369797. Comparative complete sequence analysis of the NVgz01 with reported human Nomvirus genomic sequences revealed that this strain belongs to genogroup Ⅱ.The ORF1 and ORF2 regions shared different identity with Mc37 and Farmington Hills strains, and it was considered that NVgz01 may be a recombinant virus.