Genetic heterogeneity of G and F protein genes from Argentinean human metapneumovirus strains.
Human metapneumovirus (hMPV) is a newly identified paramixovirus, associated with respiratory illnesses in all age groups. Two genetic groups of hMPV have been described. The nucleotide sequences of the G and F genes from 11 Argentinean hMPV strains (1998-2003) were determined by RT-PCR and direct sequencing. Phylogenetic analysis showed that hMPV strains clustered into two main genetic lineages, A and B. Strains clustered into A group were split into two sublineages, A1 and A2. All strains belonging to group B clustered with representative strains from sublineage B1. No Argentinean strains belonged to sublineage B2. F sequences showed high percentage identities at nucleotide and amino acid levels. In contrast, G sequences showed high diversity between A and B groups. Most changes observed in the deduced G protein sequence were amino acid substitutions in the extracellular domain, and changes in stop codon usage leading to different lengths in the G proteins. High content of serine and threonine residues were also shown, suggesting that this protein would be highly glycosylated. The potential sites for N- and O-glycosylation seem to have a different conservation pattern between the two main groups. This is the first report on the genetic variability of the G and F protein genes of hMPV strains in South America. Two main genetic groups and at least three subgroups were revealed among Argentinean hMPV strains. The F protein seems to be highly conserved, whereas the G protein showed extensive diversity between groups A and B.
Laboratorio de Virología Clínica, Centro de Educación Médica e Investigaciones Clínicas, CEMIC, Hospital Universitario, Buenos Aires, Argentina.
Monica
M
Galiano
Alfonsina
A
Trento
Lorena
L
Ver
Guadalupe
G
Carballal
Cristina
C
Videla
D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D001118:Argentina; D002675:Child, Preschool; D016384:Consensus Sequence; D005814:Genes, Viral / Q000235:genetics*; D014644:Genetic Variation; D006023:Glycoproteins / Q000235:genetics*; D006801:Humans; D007223:Infant; D029121:Metapneumovirus / Q000145:classification / Q000235:genetics*; D008969:Molecular Sequence Data; D018184:Paramyxoviridae Infections / Q000821:virology*; D016133:Polymerase Chain Reaction; D016415:Sequence Alignment; D013045:Species Specificity; D014760:Viral Fusion Proteins / Q000235:genetics*; D014764:Viral Proteins / Q000235:genetics*
C484233:G glycoprotein, human metapneumovirus; D006023:Glycoproteins; D014760:Viral Fusion Proteins; D014764:Viral Proteins