title: Glycosylation site alteration in the evolution of influenza A (H1N1) viruses.
abstract: Influenza virus typically alters protein glycosylation in order to escape immune pressure from hosts and hence to facilitate survival in different host environments. In this study, the patterns and conservation of glycosylation sites on HA and NA of influenza A/H1N1 viruses isolated from various hosts at different time periods were systematically analyzed, by employing a new strategy combining genome-based glycosylation site prediction and 3D modeling of glycoprotein structures, for elucidation of the modes and laws of glycosylation site alteration in the evolution of influenza A/H1N1 viruses. The results showed that influenza H1N1 viruses underwent different alterations of protein glycosylation in different hosts. Two alternative modes of glycosylation site alteration were involved in the evolution of human influenza virus: One was an increase in glycosylation site numbers, which mainly occurred with high frequency in the early stages of evolution. The other was a change in the positional conversion of the glycosylation sites, which was the dominating mode with relatively low frequency in the later evolutionary stages. The mechanisms and possibly biological functions of glycosylation site alteration for the evolution of influenza A/H1N1 viruses were also discussed. Importantly, the significant role of positional alteration of glycosylation sites in the host adaptation of influenza virus was elucidated. Although the results still need to be supported by experimental data, the information here may provide some constructive suggestions for research into the glycosylation of influenza viruses as well as even the design of surveillance and the production of viral vaccines.
authors.affiliation: Laboratory of Functional Glycomics, College of Life Sciences, National Engineering Research Center for Miniaturized Detection System, Northwest University, Xi'an, People's Republic of China.
authors.forename: Shisheng
authors.initials: S
authors.lastname: Sun
authors.forename: Qinzhe
authors.initials: Q
authors.lastname: Wang
authors.forename: Fei
authors.initials: F
authors.lastname: Zhao
authors.forename: Wentian
authors.initials: W
authors.lastname: Chen
authors.forename: Zheng
authors.initials: Z
authors.lastname: Li
mesh_terms: D019143:Evolution, Molecular; D016679:Genome, Viral; D006031:Glycosylation; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000378:metabolism*; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000502:physiology*; D007251:Influenza, Human / Q000378:metabolism* / Q000821:virology; D008958:Models, Molecular; D009439:Neuraminidase; D010802:Phylogeny; D011487:Protein Conformation
chemical_list: D019267:Hemagglutinin Glycoproteins, Influenza Virus; C483468:hemagglutinin, human influenza A virus; D009439:Neuraminidase