The vaccinia virus A18R protein plays a role in viral transcription during both the early and the late phases of infection.
AUTOR(ES)
Simpson, D A
RESUMO
The vaccinia virus gene A18R is essential for virus infection. The loss of A18R protein function results in unregulated transcription late during virus infection from regions of the viral genome which are normally transcriptionally quiescent. We have characterized A18R protein expression in cells infected with wild-type virus and the A18R temperature-sensitive mutant Cts23. The A18R protein is expressed during early and late phases of infection. The A18R protein expressed by Cts23 virus at permissive and nonpermissive temperatures is significantly less stable than the wild-type A18R protein. The A18R protein was identified as a virion component and localized by detergent extraction to the virion core. Virions purified from cells infected with the A18R temperature-sensitive mutants Cts4, Cts22, and Cts23 are defective in early viral transcription in vitro. The mutant transcription defect is not attributable to gross defects in virion structure or virion DNA-dependent RNA polymerase activity. We conclude that the A18R protein plays a role in viral transcription during the early phase of infection as well as during the late phase.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=236868Documentos Relacionados
- Reactivation of transcription from a vaccinia virus early promoter late in infection.
- The Vaccinia Virus A18R DNA Helicase Is a Postreplicative Negative Transcription Elongation Factor
- Vaccinia virus gene A18R encodes an essential DNA helicase.
- Efficiency of processing of viral RNA during the early and late phases of productive infection by polyoma virus.
- Role of adenovirus type 2 early region 4 in the early-to-late switch during productive infection.