两株京科猪H1 N1亚型流感病毒内部基因来源的研究

Origin of internal genes of two strains of swine influenza A(H1N1) virus

目的通过内部基因研究了解两株猪(H1N1)亚型流感病毒内部基因是否含有禽流感病毒基因节段及是否与猪群中H9N2亚型毒株发生了基因重配。方法病毒在鸡胚中传代,从收获的尿囊液中提取RNA,通过逆转录合成cDNA,cDNA用PCR扩增。PCR产物用纯化试剂盒纯化,接着进行核苷酸序列测定,然后用MegAlign(Version1.03)和Editseq(Version3.69)软件进行基因进化树分析。结果两株京科猪H1N1病毒内部基因除PB2基因节段有所不同外,其余5个基因节段均相同,但与猪H1N1流感病毒内部基因相近,然而,与古典型猪H1N1毒株有差异。结论两株京科猪H1N1病毒不是基因重配株,它们的内部基因均属猪H1N1流感病毒基因系。

Objective Through the analysis of internal genes of viruses to understand whether the internal genes of two strains of swine influenza A（ H1N1 ） virus contain the gene segment deriving from avian influenza A viruses, and whether the reassortment of the internal genes occurred between swine H1N1 and swine H9N2 viruses. Methods Viruses were passaged in embryonated hen eggs and virion RNA was extracted from allantoic fluids and reverse transcribed to synthesize eDNA. eDNA was amplified by PCR and the PCR product was purified with a purification kit. Afterwards, RNA sequence analysis was performed by dideoxynucleotide chain termination and a cloning method. Finally, phylogenetic analysis of the sequencing data was performed with MegAlign （ version 1.03 ）. Results All the six, but PB2 gene segment internal gene segments were the same between A/swine/Beijing/1/2002 （ H1N1 ） and A/Swine/Beijing/3/2002 （H1N1） viruses. Whereas all the six internal gene segments in two trains of swine （H1N1） virus were similar to those of swine H1N1 viruses, but different from those of classical strain of swine （ H1N1 ） virus. Conclusion Two strains of Beijing swine H1N1 influenza A virus were not reassortant, All the six internal gene segments were closely related to swine influenza A （H1N1） viruses.