JVI Figure table search 04
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Lindstrom, S. E.
Right arrow Articles by Nerome, K.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Lindstrom, S. E.
Right arrow Articles by Nerome, K.

 Previous Article  |  Next Article 

Journal of Virology, May 1999, p. 4413-4426, Vol. 73, No. 5
0022-538X/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.

Comparative Analysis of Evolutionary Mechanisms of the Hemagglutinin and Three Internal Protein Genes of Influenza B Virus: Multiple Cocirculating Lineages and Frequent Reassortment of the NP, M, and NS Genes

Stephen E. Lindstrom, Yasuaki Hiromoto, Hidekazu Nishimura, Takehiko Saito, Reiko Nerome, and Kuniaki Nerome*

Department of Virology I, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo 162-8640, Japan

Received 9 December 1998/Accepted 9 February 1999

Phylogenetic profiles of the genes coding for the hemagglutinin (HA) protein, nucleoprotein (NP), matrix (M) protein, and nonstructural (NS) proteins of influenza B viruses isolated from 1940 to 1998 were analyzed in a parallel manner in order to understand the evolutionary mechanisms of these viruses. Unlike human influenza A (H3N2) viruses, the evolutionary pathways of all four genes of recent influenza B viruses revealed similar patterns of genetic divergence into two major lineages. Although evolutionary rates of the HA, NP, M, and NS genes of influenza B viruses were estimated to be generally lower than those of human influenza A viruses, genes of influenza B viruses demonstrated complex phylogenetic patterns, indicating alternative mechanisms for generation of virus variability. Topologies of the evolutionary trees of each gene were determined to be quite distinct from one another, showing that these genes were evolving in an independent manner. Furthermore, variable topologies were apparently the result of frequent genetic exchange among cocirculating epidemic viruses. Evolutionary analysis done in the present study provided further evidence for cocirculation of multiple lineages as well as sequestering and reemergence of phylogenetic lineages of the internal genes. In addition, comparison of deduced amino acid sequences revealed a novel amino acid deletion in the HA1 domain of the HA protein of recent isolates from 1998 belonging to the B/Yamagata/16/88-like lineage. It thus became apparent that, despite lower evolutionary rates, influenza B viruses were able to generate genetic diversity among circulating viruses through a combination of evolutionary mechanisms involving cocirculating lineages and genetic reassortment by which new variants with distinct gene constellations emerged.


* Corresponding author. Mailing address: Department of Virology I, National Institute of Infectious Diseases, 23-1, Toyama 1-chome, Shinjuku-ku, Tokyo 162-8640, Japan. Phone: (03) 5285-1111. Fax: (03) 5285-1155. E-mail: knerome{at}nih.go.jp.


Journal of Virology, May 1999, p. 4413-4426, Vol. 73, No. 5
0022-538X/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.



This article has been cited by other articles:




Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
J. Bacteriol. Mol. Cell. Biol. Microbiol. Mol. Biol. Rev.
Clin. Vaccine Immunol. ALL ASM JOURNALS

Copyright © 1999 by the American Society for Microbiology. All rights reserved.