H3N2亚型猪流感病毒NS1基因的克隆与序列分析

Cloning and sequence analysis of NS1 gene from swine influenza virus (H3N2)

从鸡胚尿囊液中提取H3N2亚型猪流感病毒(SIV)的RNA,根据已发表的A型流感病毒的核苷酸序列,设计了一对特异性引物,采用反转录-聚合酶链反应(RT-PCR)成功地扩增了SIV的NS1基因．将NS1基因的cDNA克隆后进行了序列测定,测序结果表明,所扩增的778 nt片段包含了完整的NS1基因的开放阅读框．核苷酸序列比较分析结果表明,该毒株与A／Swine／Texas／4199-2／98(H3N2)、A／Swine／Iowa／533／99(H3N2)、A／Swine／HongKong／126／ 82(H3N2)、A／Swine／Pingtung／7-12／99(HIN2)核苷酸序列的同源性为92．7％～98．6％,推导的氨基酸序列同源性为92．6％～96．3％．

The swine influenza virus （SIV）RNA were directly extracted and purified from chicken embryo allantoic fluid. According to the published A type influenza virus nucleatide sequence,a pair of specific primers were designed to amplify the NS1 gene of SIV by reverse transcription-polymerase chain reaction reaction（RT-PCR）. Then the eDNA of NS1 gene was cloned and sequenced. The results showed that the cloned 778 nt fragment covered the whole NS1 gene including the completely open reading fram. When comparing with A/Swine/Texas/4199 - 2/98 （H3N2）, A/Swine/Iowa/533/99 （H3N2）, A/Swine/ HongKong/t26/82（H3N2） and A/Swine/Pingtung/7- 12/99 （H1N2）, the homology of nucleotide sequence ranged from 92.7 0% to 96.6%,and homology of deduced amino acid was from 92.6% to 96.3 %.