[Variation and evolution analysis of the PB1-F2 genes of novel influenza A viruses isolated from Guangzhou China].

To compare and analyze the variation of PB1-F2 genes of Influenza A Viruses from Guangzhou during 2009 to 2011 with the Influenza A Viruses from all over the world, to lay the foundation of functional research and interaction mechanism of the PB1-F2 protein. 17 Novel H1N1 influenza viruses and 1 seasonal H1N1 influenza virus have been isolated from human in Guangzhou during 2009 to 2011 that were cloned into pMD 18-T Vector for sequencing. Then, 68 PB1-F2 genes of IAVs from human around the world were downloaded from GenBank database and analyzed using molecular biological software. The phylogenetic tree result shows that the PB1-F2 genes of IAV from the world separated into two main groups. There is high homology of PB1-F2 genes of one Seasonal H1N1 virus and Novel H1N1 viruses which were isolated in Guangzhou compared with the global Novel H1N1 viruses. And all of them got the 11 amino acids truncated protein by mutation included one seasonal H1N1 strain isolated by our laboratory. There is no variation of PB1-F2 genes of Novel H1N1 virus in Guangzhou compared with the worldwide strains. However, one seasonal H1N1 virus which isolated by our laboratory shows analogous truncated mutation of PB1-F2 of Novel H1N1 virus, it reveals that the PB1-F2 gene might has done the early reassortment between the Novel H1N1 virus and seasonal H1N1 virus.