Molecular characterization of hepatitis E virus ORF1 gene supports a papain-like cysteine protease (PCP)-domain activity.
Virus Res
; 178(2): 553-6, 2013 Dec 26.
Article
en En
| MEDLINE
| ID: mdl-23978667
Hepatitis E Virus (HEV) ORF1 encodes the nonstructural polyprotein wherein a role of PCP-domain in ORF1 proteolysis and/or RNA replication still remains contested. A series of ORF1 mutants of HEV-SAR55 replicon were constructed and tested for viability in S10-3 cells. Six of PCP-'cysteine' (C457A, C459A, C471A, C472A, C481A and C483A) and three 'histidine' (H443L, H497L and H590L) mutants were lethal. Further, a highly conserved 'glycine-triad' (G815-G816-G817) in downstream X-domain, homologous to rubella virus protease-substrate (G1299-G1300-G1301) was identified where two of X-mutants (G816V and G817V) turned lethal. However, all ORF1 sequential nucleotide-mutants conserving the amino acids were viable, which clearly showed post-translational regulation of HEV replication by PCP- and X-domains. Moreover, while vector-expressed ORF1-fusion polyprotein yielded a ~191 kDa band in vitro, it produced ~78 and ~35 kDa fragments ex vivo. Collectively, the indispensability and functional effects of 'PCP-catalytic' and 'X-substrate' residues on HEV replication strongly supported a viral protease.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Virus de la Hepatitis E
/
Proteínas no Estructurales Virales
/
Proteasas de Cisteína
Límite:
Humans
Idioma:
En
Revista:
Virus Res
Asunto de la revista:
VIROLOGIA
Año:
2013
Tipo del documento:
Article
Pais de publicación:
Países Bajos