A single positively selected West Nile viral mutation confers increased virogenesis in American crows.
Nat Genet
; 39(9): 1162-6, 2007 Sep.
Article
em En
| MEDLINE
| ID: mdl-17694056
ABSTRACT
West Nile virus (WNV), first recognized in North America in 1999, has been responsible for the largest arboviral epiornitic and epidemic of human encephalitis in recorded history. Despite the well-described epidemiological patterns of WNV in North America, the basis for the emergence of WNV-associated avian pathology, particularly in the American crow (AMCR) sentinel species, and the large scale of the North American epidemic and epiornitic is uncertain. We report here that the introduction of a T249P amino acid substitution in the NS3 helicase (found in North American WNV) in a low-virulence strain was sufficient to generate a phenotype highly virulent to AMCRs. Furthermore, comparative sequence analyses of full-length WNV genomes demonstrated that the same site (NS3-249) was subject to adaptive evolution. These phenotypic and evolutionary results provide compelling evidence for the positive selection of a mutation encoding increased viremia potential and virulence in the AMCR sentinel bird species.
Texto completo:
1
Bases de dados:
MEDLINE
Assunto principal:
Vírus do Nilo Ocidental
/
Doenças das Aves
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Corvos
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Mutação
Limite:
Animals
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Humans
Idioma:
En
Revista:
Nat Genet
Assunto da revista:
GENETICA MEDICA
Ano de publicação:
2007
Tipo de documento:
Article
País de afiliação:
Estados Unidos