Analysis of Influenza A/Beijing/353/89 Virus Matrix Gene Sequence and Identification of Replaceable Amino Acids as Natural Mutations in M2 Protein
Yongxin Zhang *
Zyxell Inc., Carrollton, TX75007, USA and Department of Molecular Virology and Microbiology, Respiratory Pathogens Research Unit, Influenza Research Center, Baylor College of Medicine, Houston, Texas 77030, USA.
Monica Zhang
Zyxell Inc., Carrollton, TX75007, USA
Ying Wang
Zyxell Inc., Carrollton, TX75007, USA and Department of Molecular Virology and Microbiology, Respiratory Pathogens Research Unit, Influenza Research Center, Baylor College of Medicine, Houston, Texas 77030, USA.
Xyanthine Gilmore
Department of Molecular Virology and Microbiology, Respiratory Pathogens Research Unit, Influenza Research Center, Baylor College of Medicine, Houston, Texas 77030, USA.
Innocent N. Mbawuike
Department of Molecular Virology and Microbiology, Respiratory Pathogens Research Unit, Influenza Research Center, Baylor College of Medicine, Houston, Texas 77030, USA.
*Author to whom correspondence should be addressed.
Abstract
The influenza virus A/Beijing/353/89 matrix (M), M1 and M2 genes were cloned and sequenced. The sequence identity rates (based on published data) of the first 34 influenza A viruses with M genes most phylogenetically related to A/Beijing/353/89 virus were in significant positive correlation among M, M1 and M2 genes and M1 protein but not M2 protein. The number of viruses with M2 protein sequences identical to influenza A/Beijing/353/89 virus was significantly higher than those with identical M2 gene and M1 protein sequences (P<0.01). These results suggest that natural variation of M2 protein did not occur entirely in random. Based on a statistical standard we have established and using the A/Beijing/353/89 M2 as reference protein, 35 replaceable amino acids were identified by analysis of 193 published influenza A virus M2 protein sequences. In contrast, it is more possible that those critical amino acids for virus survival and/or replication harbored in the 24 amino acids, which were not yet found to have ever been substituted.
Keywords: Influenza virus, matrix gene, sequence analysis and variation