H_6N_2亚型禽流感病毒血凝素基因的克隆及其序列分析

CLONING AND ANALYSIS OF HA GENE SEQUENCE OF H_6N_2 SUBTYPE AVIAN INFLUENZA VIRUS(AIV)

设计特异引物,采用RT-PCR技术,成功从本实验室分离、保存的H6N2禽流感病毒毒株(HB 2002)中克隆到血凝素基因(HA)序列,该克隆基因全长1 714 bp,提交GenBank,获得登录号DQ 285546。同部分H6,H5,H7,H9亚型禽流感病毒HA基因序列分析表明,该基因核酸、氨基酸序列与A/duck/Hainan/4/2004(H6N2),A/duck/HongKong/3600/99(H6N2)毒株有99%的相似性;分子进化分析结果显示,该基因与此2毒株亲缘关系最近。由该克隆核酸序列推导的HA蛋白共566个氨基酸,该蛋白同其他H6亚型AIV的HA蛋白有相同裂解位点序列即PQIETR↓G,无高致病性毒株典型的裂解位点特征,因此,初步判定毒株HB 2002为低致病性禽流感病毒。

With a set of specific primers, the hemagglutinin （HA） gene （1. 714 bp in length） of the experimental virulenl strain （HB 2002） of avian influenza virus （AIV） was amplified by RT-PCR and successfully cloned to PGEM-T vector. After detecting the cloned sequence and submitting it to Genbank, its accession nunber was recorded as DQ 285546. The identities of nueleotides and amino acid sequence with Genbank, the motif of cleave sites and the phylogenetie relations were analyzed. The results suggested that the naeleotide and amino acid sequence of the experimental strain shared 99% identity with the Hainan and Hong Kong strains （A/duek/Hainan/6/0/1 （H6N2 ）, A/duek/Hong Kong/3600/99 H6N2 ） anti was closed related to the two strains phylogenetieally. The cleave site character of hemagglutinin was PQIETR↓, G, which was the same as the other H6 subtype AIV and different from the highly pathogenie avian influenza （HPAI）.