Varicella-Zoster Virus (VZV) ORF17 Protein Induces RNA Cleavage and Is Critical for Replication of VZV at 37oC but Not 33oC
AUTOR(ES)
Sato, Hitoshi
FONTE
American Society for Microbiology
RESUMO
Varicella-zoster virus (VZV) open reading frame 17 (ORF17) is homologous to herpes simplex virus (HSV) UL41, which encodes the viral host shutoff protein (vhs). HSV vhs induces degradation of mRNA and rapid shutoff of host protein synthesis. An antibody to ORF17 protein detected a 46-kDa protein in VZV-infected cells. While HSV vhs is located in virions, VZV ORF17 protein was not detectable in virions. ORF17 protein induced RNA cleavage, but to a substantially lesser extent than HSV-1 vhs. Expression of ORF17 protein did not inhibit expression from a β-galactosidase reporter plasmid, while HSV type 1 vhs abolished reporter expression. Two VZV ORF17 deletion mutants were constructed to examine the role of ORF17 in virus replication. While the ORF17 VZV mutants grew to peak titers that were similar to those of the parental virus at 33°C, the ORF17 mutants grew to 20- to 35-fold-lower titers than parental virus at 37°C. ORF62 protein was distributed in a different pattern in the nuclei and cytoplasm of cells infected with an ORF17 deletion mutant at 37°C compared to 33°C. Inoculation of cotton rats with the ORF17 deletion mutant resulted in a level of latent infection similar to that produced by inoculation with the parental virus. The importance of ORF17 protein for viral replication at 37°C but not at 33°C suggests that this protein may facilitate the growth of virus in certain tissues in vivo.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=136605Documentos Relacionados
- Varicella-Zoster Virus (VZV) ORF32 Encodes a Phosphoprotein That Is Posttranslationally Modified by the VZV ORF47 Protein Kinase
- Generation of varicella-zoster virus (VZV) and viral mutants from cosmid DNAs: VZV thymidylate synthetase is not essential for replication in vitro.
- The varicella-zoster virus (VZV) open reading frame 47 (ORF47) protein kinase is dispensable for viral replication and is not required for phosphorylation of ORF63 protein, the VZV homolog of herpes simplex virus ICP22.
- The varicella-zoster virus ORF66 protein induces kinase activity and is dispensable for viral replication.
- Varicella-zoster virus (VZV) open reading frame 61 protein transactivates VZV gene promoters and enhances the infectivity of VZV DNA.