甲型流感病毒(H1N2)亚型毒株血凝素和神经氨酸酶基因来源的研究

Study on the origin of influenza A(H1N2) virus HA and NA genes

目的 研究新分离到的H1N2亚型毒株血凝素 (HA)和神经氨酸酶 (NA)基因的来源。方法 病毒通过鸡胚增殖后提取其RNA ,通过逆转录合成cDNA ,经PCR扩增和产物纯化 ,用双脱氧链终止法进行核苷酸序列测定 ,并用MegAlign(1 0 3版 )和Editseq(3 6 9版 )软件进行种系发生学分析。结果 新分离到H1N2毒株HA1区氨基酸序列与A/PR/ 8/ 34 (H1N1)和A/Guangdong/ 6 / 91(H1N1)毒株间的同源性分别为 98 2 %和 99 4% ;NA蛋白分子氨基酸序列与 1995年的甲 3(H3N2 )亚型毒株间同源性高达 99 1%。结论 新分离的H1N2毒株是A/PR/ 8/ 34 (H1N1)类毒株与甲 3(H3N2 )亚型毒株通过基因重配而来。

Objective To determine the origins of the HA and NA genes of new subtype (H1N2) of influenza A virus. Methods Virus was amplified in embryonated chicken eggs, then virion RNA was transcribed into cDNA by reverse transcriptase, cDNA amplified by PCR, the products of PCR were purified. Afterward, RNA sequence analysis was performed by the dideoxynucleotide chain termination method, using synthetic oligodideoxynucleotide primers. Finally, phylogenetic analysis of the sequencing data was performed with MegAlign (Version 1 03) and Editseq (Version 3 69) softwares. Results The homology of amino acid sequences of protein molecules on HA1 domains when compared, with A/PR/8/34(H1N1) and A/Guangdong/6/91(H1N1) viruses was 98 2% and 99 4%, respectively. The homology of amino acid sequences of NA protein molecules between the novel reassortant and H1N1 virus was only 83 4%, but the homology of those between H1N2 strain and H3N2 virus circulating in men in 1995 was as high as 99 1%. Conclusion The new reassortant(H1N2) virus HA gene was derived from A/PR/8/34(H1N1) like virus, but its NA gene was derived from H3N2 virus circulating in men in 1995.