Characterization of the human cytomegalovirus irs1 and trs1 genes: A second immediate-early transcription unit within irs1 whose product antagonizes transcriptional activation

Michael J. Romanowski, Thomas Shenk

Research output: Contribution to journalArticle

64 Scopus citations

Abstract

We have characterized the irs1 and trs1 genes of human cytomegalovirus. The previously identified mRNAs as well as their corresponding protein products pIRS1 and pTRS1 could be detected during all phases of the viral replications cycle. The proteins were present in the nucleus and cytoplasm during the immediate-early and early phases of the viral growth cycle but were predominantly cytoplasmic late after infection. Although pIRS1 and pTRS1 exhibited little transcriptional activation potential on their own, both cooperated with the IE1 and IE2 proteins to enhance expression from a variety of viral promoters. We have also identified a previously undescribed immediate-early gene product encoded within the irs1 gene that we have termed pIRS1263. This new protein is encoded within the 3' end of the irs1 gene and is in the same reading frame as the large pIRS1 protein. Expression of the ir1263 gene is controlled by a promoter that resides within the irs1 open reading frame in the unique short region of the viral genome. pIRS1263 resides in the nucleus and antagonizes transcriptional activation by cytomegalovirus immediate-early proteins. We propose that pIRS263, whose promoter responds in immediate-early transcriptional activators, serves as part of a regulatory loop, antagonizing the function of the vital proteins that are responsible for its synthesis.

Original languageEnglish (US)
Pages (from-to)1485-1496
Number of pages12
JournalJournal of virology
Volume71
Issue number2
DOIs
StatePublished - Feb 1997

All Science Journal Classification (ASJC) codes

  • Microbiology
  • Immunology
  • Insect Science
  • Virology

Fingerprint Dive into the research topics of 'Characterization of the human cytomegalovirus irs1 and trs1 genes: A second immediate-early transcription unit within irs1 whose product antagonizes transcriptional activation'. Together they form a unique fingerprint.

  • Cite this