Evolutionary Dynamics of a Highly Pathogenic Type 2 Porcine Reproductive and Respiratory Syndrome Virus: Analyses of Envelope Protein-Coding Genes.
Transbound Emerg Dis
; 62(4): 411-20, 2015 Aug.
Article
em En
| MEDLINE
| ID: mdl-23981823
ABSTRACT
Porcine reproductive and respiratory syndrome virus (PRRSV) has long been an economically devastating swine viral disease. The recent emergence of a highly pathogenic type 2 PRRSV with high mobility and mortality in China, spreading in Vietnam, Laos, and Thailand has placed neighbouring countries at risk. This study applied a codon-based extension of the Bayesian relaxed clock model and the fixed effects maximum-likelihood method to investigate and compare the evolutionary dynamics of type 2 PRRSV for all of known structural envelope protein-coding genes. By comparing the highly pathogenic type 2 PRRSV clade against the typical type 2 PRRSV clade, this study demonstrated that the highly pathogenic clade evolved at high rates in all of the known structural genes but did not display rapid evolutionary dynamics compared with typical type 2 PRRSV. In contrast, the ORF3, ORF5 and ORF6 genes of the highly pathogenic clade evolved in a qualitatively different manner from the genes of the typical clade. At the population level, several codons of the sequence elements that were involved in viral neutralization, as well as codons that were associated with in vitro attenuation/over-attenuation, were predicted to be selected differentially between the typical clade and the highly pathogenic clade. The results of this study suggest that the multigenic factors of the envelope protein-coding genes contribute to diversifying the biological properties (virulence, antigenicity, etc.) of the highly pathogenic clade compared with the typical clade of type 2 PRRSV.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas do Envelope Viral
/
Evolução Molecular
/
Vírus da Síndrome Respiratória e Reprodutiva Suína
/
Síndrome Respiratória e Reprodutiva Suína
Tipo de estudo:
Prognostic_studies
Limite:
Animals
País/Região como assunto:
Asia
Idioma:
En
Ano de publicação:
2015
Tipo de documento:
Article