一株H3亚型野鸟源禽流感病毒血凝素基因序列分析

为了解野鸟在传播禽流感病毒中的作用,贵州省动物疫病预防控制中心定期从威宁草海采集候鸟和留鸟的新鲜粪便,用RT-PCR方法检测病原核酸。监测到1份流感病毒阳性样本,对其血凝素(HA)基因进行了克隆和测序。结果发现,该病毒属于H3亚型,所获得的HA基因1794 bp,包含有完整的阅读框架,编码566个氨基酸残基,包括6个潜在的糖基化位点,遗传进化分析结果显示其属于欧亚禽源分支。另外,HA受体结合位点上的氨基酸序列具有禽源特有的保守性,分别是154A、206E、210L、241G、242Q和244G。推导的HA裂解位点有典型的低致病特征(PEKQTR/GLF)。结果表明,贵州省野鸟中存在低致病性H3亚型禽流感病毒。

Sequence Analysis of HA Gene of Wild Bird-origin H3 Subtype Avian Influenza Virus

In order to understand the role of the wild birds in the transmission of avian influenza viruses (AIV), fresh stool from migratory birds and resident birds in Weining Caohai acquisition were collected and detected by RT-PCR. A flu virus positive sample was detected and the haemagglutinin (HA) gene was cloned and sequenced. Results showed that the AIV was subtyped into H3 and the HA fragment was 1794 bp belonging to the Eurasian lineage, which had one open reading frame and encoded 566 amino acids including 6 potential glycosylation sites. In addition, it had conserved amino acid sequences of influenza viruses of avian origin such as A, E, L, G, Q and G at position of 154, 206, 210, 241, 242 and 244, respectively, in the receptor binding site on the HA. The deduced amino acid sequences of the HA cleavage site had a typical low pathogenic motif (PEKQTR/GLF). The result showed that the low pathogenic H3 subtype AIV strain was circulating in wild birds of Guizhou province.