H9N2亚型禽流感病毒广东分离株的全基因克隆及序列分析  

Cloning and Analysis of Full-length Genes of a H9N2 Subtype Avian Influenza Virus Isolated from Guangdong

作　　者：齐岩[1,2] 袁润余[1,2] 张贺楠[1,2] 亓文宝[1,2] 单芬[1,2] 胡玥[1,2] 李小康[1,2] 焦培荣[1,2] 廖明[1,2] 

机构地区：[1]华南农业大学兽医学院,广州510642 [2]农业部动物疫病防控重点开放实验室,广东省动物源性人兽共患病预防与控制重点实验室,广州510642

出　　处：《病毒学报》2010年第3期176-182,共7页Chinese Journal of Virology

基　　金：国家863计划项目(2006AA10A205);国家科技支撑计划(2006BAD06A16-2);教育部创新团队项目(IRT0723);广东省自然科学基金创新团队项目(5200638)资助

摘　　要：本研究以一株2006年广东省分离的H9N2亚型禽流感病毒A/Chicken/Guangdong/HL/2006(H9N2)(简称Ck/GD/HL/06)为研究对象,用RT-PCR法扩增病毒基因组各片段(包括5′端和3′端的非编码区序列),将扩增片段进行克隆、测序并与参考毒株的相应序列进行比较分析,绘制各基因片段的系统发生树。分析结果表明,Ck/GD/HL/06株的HA基因同1997年中国香港鸭源毒株Dk/HK/Y280/97(H9N2)在同一进化分支,从HA的糖基化位点、受体结合位点等综合分析,该毒株HA基因未发生明显的变异,符合我国大陆H9亚型禽流感病毒的特点。HA的226位氨基酸残基为亮氨酸(Leu),具有同哺乳动物SAα,2-6受体结合的特性。Ck/GD/HL/06的PB1、PA和NP基因,同2004年越南分离的人源高致病性H5N1亚型流感病毒A/VietNam/1203/2004(H5N1)株(简写A/VN/1203/04)的核苷酸序列一致性分别是93.8%、95%和96.8%,在先前的研究中未见有类似特性毒株的报道,而这种特性H9N2亚型AIV的出现,是否会增加在重组过程中产生新的高致病性H5N1亚型AIV的可能性,是值得我们关注的一个问题,也提醒在我国华南地区应更加重视防控H9N2亚型AIV,做好长期对H9N2亚型AIV监控及分子流行病学调查的工作。Eight full-length genes of an avian influenza virus Chinese isolate of H9N2 subtype,A/Chicken/Guangdong/HL/2006 （H9N2） （abbreviated as Ck/GD/HL/06）,were amplified by RT-PCR,including the 5＇ and 3＇ non-coding region. All the genes were cloned and sequenced. The phylogenetic analysis results showed the HA gene of Ck/GD/HL/06 was located in the same phylogenetic clade as Dk/HK/Y280/97 （H9N2）,while the Dk/HK/Y280/97-like viruses had been predominately isolated from chickens in China's Mainland. After the analysis of glycosylation sites and receptor-binding sites in the HA,it was shown that the HA of Ck/GD/HL/06 exhibited the common feature of H9 subtype avian influenza virus isolated from China,but the leucine （Leu） residue at the amino acid position 226 indicated the potential of binding with SAα,2-6 receptor. The three internal genes of Ck/GD/HL/06 （PB1,PA and NP） had the highest nucleotide identity with A/Viet Nam/1203/2004 （abbreviated A/VN/1203/04） isolate,which was shown to be transmitted from chickens to human and caused lethal infection in human. No analogous H9N2 strains was reported in previous studies. Based on the high similarity of Ck/GD/HL/06 three genes to A/VN/1203/04,it was suggested that the possibility of generating new highly pathogenic H5N1 AIVs by recombination was worthy of our attention. Further studies should be needed for molecular epidemiologic surveillance of H9N2 AIV in the south China for a long time.

关 键 词：禽流感病毒 H9N2亚型 全基因 克隆 序列分析 

分 类 号：S852.65[农业科学—基础兽医学]