tetano
Editor, Senior Moderator
J Gen Virol. 2012 Jun 20. [Epub ahead of print]
Genetic Evolution of Neuraminidase of Influenza A (H3N2) Viruses from 1968 to 2009 and its Correspondence to Hemagglutinin.
Westgeest KB, de Graaf M, Fourment M, Bestebroer TM, van Beek R, Spronken MI, de Jong JC, Rimmelzwaan GF, Russell CA, Osterhaus AD, Smith GJ, Smith DJ, Fouchier RA.
Source
Department of Virology, Erasmus MC Rotterdam;
Abstract
Each year, influenza viruses cause epidemics by evading preexisting humoral immunity through mutations in the major glycoproteins: the hemagglutinin (HA) and the neuraminidase (NA). In 2004, Smith et al. mapped the antigenic evolution of HA of human influenza A (H3N2) viruses from its introduction in humans in 1968 until 2003. Here, we have focused on the genetic evolution of NA and compared it to HA using the dataset of Smith et al., updated to the epidemic of the 2009/2010 season. Phylogenetic trees and genetic maps were constructed to visualize the genetic evolution of NA and HA. The study revealed multiple reassortment events over the years. Overall rates of evolutionary change were lower for NA than for HA1 at the nucleotide level. Selection pressures were estimated revealing an abundance of negatively selected sites and sparse positively selected sites. The differences found between the evolution of NA and HA1 warrant further analysis of the evolution of NA at the phenotypic level, as was previously done for HA.
PMID:
22718569
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/22718569
Genetic Evolution of Neuraminidase of Influenza A (H3N2) Viruses from 1968 to 2009 and its Correspondence to Hemagglutinin.
Westgeest KB, de Graaf M, Fourment M, Bestebroer TM, van Beek R, Spronken MI, de Jong JC, Rimmelzwaan GF, Russell CA, Osterhaus AD, Smith GJ, Smith DJ, Fouchier RA.
Source
Department of Virology, Erasmus MC Rotterdam;
Abstract
Each year, influenza viruses cause epidemics by evading preexisting humoral immunity through mutations in the major glycoproteins: the hemagglutinin (HA) and the neuraminidase (NA). In 2004, Smith et al. mapped the antigenic evolution of HA of human influenza A (H3N2) viruses from its introduction in humans in 1968 until 2003. Here, we have focused on the genetic evolution of NA and compared it to HA using the dataset of Smith et al., updated to the epidemic of the 2009/2010 season. Phylogenetic trees and genetic maps were constructed to visualize the genetic evolution of NA and HA. The study revealed multiple reassortment events over the years. Overall rates of evolutionary change were lower for NA than for HA1 at the nucleotide level. Selection pressures were estimated revealing an abundance of negatively selected sites and sparse positively selected sites. The differences found between the evolution of NA and HA1 warrant further analysis of the evolution of NA at the phenotypic level, as was previously done for HA.
PMID:
22718569
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/22718569