Regulation of expression of the Epstein-Barr virus BamHI-A rightward transcripts

J Virol. 2005 Feb;79(3):1724-33. doi: 10.1128/JVI.79.3.1724-1733.2005.

Abstract

The Epstein-Barr virus (EBV) BamHI-A rightward transcripts, or BARTs, are a family of mRNAs expressed in all EBV latency programs, including EBV-infected B cells in healthy carriers. Despite their ubiquitous expression, the regulation and biological function of BARTs are still unclear. In this study, the BART 5' termini were characterized by using a procedure that selects capped, full-length mRNAs. Two TATA-less promoter regions, designated P1 and P2, were mapped. P1 had relatively high basal activity in both epithelial and B cells, whereas P2 exhibited higher activity in epithelial cells. Upon EBV infection of B cells, transcription from P1 was detected soon after infection, while expression from P2 was delayed. Promoter-reporter assays in transiently transfected cells revealed that P1 and P2 were differentially regulated. Interferon regulatory factor 7 (IRF7) and IRF5 negatively regulated P1 activity. c-Myc and C/EBP family members positively regulated P2. Regulation of P2 by C/EBPs was characterized by electrophoretic mobility shift assay, chromatin immunoprecipitation, and reporter assays. More-abundant BART expression in epithelial cells correlated with the relative expression of positive and negative regulators in these cells.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • B-Lymphocytes / virology
  • Base Sequence
  • Cell Line
  • Deoxyribonuclease BamHI / metabolism*
  • Epithelial Cells / virology
  • Gene Expression Regulation, Viral*
  • HeLa Cells / virology
  • Herpesvirus 4, Human / genetics
  • Herpesvirus 4, Human / metabolism
  • Herpesvirus 4, Human / pathogenicity*
  • Humans
  • Molecular Sequence Data
  • Promoter Regions, Genetic*
  • Restriction Mapping*
  • Transcription, Genetic*

Substances

  • Deoxyribonuclease BamHI