Purifying selection in porcine reproductive and respiratory syndrome virus ORF5a protein influences variation in envelope glycoprotein 5 glycosylation.
Infect Genet Evol
; 20: 362-8, 2013 Dec.
Article
en En
| MEDLINE
| ID: mdl-24084290
Porcine reproductive and respiratory syndrome virus ORF5a protein is encoded in an alternate open reading frame upstream of the major envelope glycoprotein (GP5) in subgenomic mRNA5. Bioinformatic analysis of 3466 type 2 PRRSV sequences showed that the two proteins have co-evolved through a fine balance of purifying codon usage to maintain a conserved RQ-rich motif in ORF5a protein, while eliciting a variable N-linked glycosylation motif in the alternative GP5 reading frame. Conservation of the ORF5a protein RQ-motif also explains an anomalous uracil desert in GP5 hypervariable glycosylation region. The N-terminus of the mature GP5 protein was confirmed to start with amino acid 32, the hypervariable region of the ectodomain. Since GP5 glycosylation variability is assumed to result from immunological selection against neutralizing antibodies, these findings show that an alternative possibility unrelated to immunological selection not only exists, but provides a foundation for investigating previously unsuspected aspects of PRRSV biology. Understanding functional consequences of subtle nucleotide sequence modifications in the region responsible for critical function in ORF5a protein and GP5 glycosylation is essential for rational design of new vaccines against PRRS.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Proteínas del Envoltorio Viral
/
Virus del Síndrome Respiratorio y Reproductivo Porcino
/
Síndrome Respiratorio y de la Reproducción Porcina
Límite:
Animals
Idioma:
En
Revista:
Infect Genet Evol
Asunto de la revista:
BIOLOGIA
/
DOENCAS TRANSMISSIVEIS
/
GENETICA
Año:
2013
Tipo del documento:
Article
Pais de publicación:
Países Bajos