福建省禽流感病毒非结构蛋白基因特征分析

目的 明确福建省不同亚型不同源的禽流感病毒非结构蛋白基因(non-structural gene, NS)的遗传进化关系及氨基酸变异特征。方法 将2011年分离的毒株A/Chicken/Fujian/FZ04/2011(H9N2)(FZ-04株)、A/Chicken/Fujian/FZ11/2011(H9N2)(FZ-11株)的NS基因,与GenBank上登录的1997-2011年福建省不同源不同亚型的AIV毒株及国内外代表株的NS基因进行序列比对和遗传进化分析。结果 FZ-04和FZ-11株与福建省AIV的NS基因同源性分别为88.2%～99.0%,88.3～99.4%。福建省H5N1亚型毒株均属于Y439亚群,H9N2亚型毒株均属于Y280亚群。福建仅H5N1毒株的NS1蛋白80-84位有5个氨基酸缺失,且在羧基末端存在ESEV/GSEV两种PL基序,这可能是福建省区分高致病性和低致病性禽流感病毒的标志之一。结论 NS基因的特征分析表明,福建省H9N2毒株没有向高致病性H5N1毒株突变的嗜性,为今后进一步分析福建省禽流感病毒的NS基因遗传进化关系及毒力变异提供科学依据。

Genetic characterization of non-structural gene of avian influenza virus in Fujian

To determine the genetic characterization of different subtypes and different origins of avian influenza viruses, sequence analysis and phylogenetic studies were conducted by comparing with each NS gene of H9N2 strain isolated in Fujian during 1997-2011 and those of the representative H9N2 strains in China were submitted to GenBank. The phylogenetic analysis showed that the NS gene of HgN2 subtype belonged to the genetic Y280-1ike sublineage, while H5N1 subtype belonged to the genetic Y439-1ike sublineage. The homologies of the nucleotide sequences of NS genes of FZ-04 and FZ-11 were 88. 20% to 99.0% and 88.3 to 99.4%, respectively. Only H5N1 strains isolated in Fujian had five amino acid deletions in 80-84 positions, all of which had “ESEV/GSEV” PDZ ligand （PL） C-terminal motif in their NS1 proteins. Comparative and genetic character- ization analysis showed that the NS proteins contained few amino acid sequences associated with highly pathogenic HSN1 avian influenza viruses.