Viral induction of the human beta interferon promoter: modulation of transcription by NF-kappa B/rel proteins and interferon regulatory factors.

Abstract

Multiple regulatory domains within the -100 region of the beta interferon (IFN-beta) promoter control the inducible response of the IFN gene to virus infection. In this study, we demonstrate that the formation of NF-kappa B-specific complexes on the positive regulatory domain II (PRDII) precedes the onset of detectable IFN-beta transcription in Sendai virus-infected cells. By using NF-kappa B subunit-specific antibodies, a temporal shift in the composition of NF-kappa B subunits in association with the PRDII domain is detected as a function of time after virus infection. Furthermore, a virus-induced degradation of I kappa B alpha (MAD3) protein is observed between 2 and 8 h after infection; at later times, de novo synthesis of I kappa B alpha restores I kappa B alpha to levels found in uninduced cells and correlates with the down regulation of IFN-beta transcription. In cotransfection experiments using various NF-kappa B subunit expression plasmids and two copies of PRDII/NF-kappa B linked to a chloramphenicol acetyltransferase reporter gene, we demonstrate that expression of p65, c-Rel, or p50 or combinations of p50-p65 and p65-c-Rel differentially stimulated PRDII-dependent transcription. Coexpression of I kappa B alpha completely abrogated p65-, c-Rel-, or p65-p50-induced gene activity. When the entire IFN-beta promoter (-281 to +19) was used in coexpression studies, synergistic stimulation of IFN-beta promoter activity was obtained when NF-kappa B subunits were coexpressed together with the IFN regulatory factor 1 (IRF-1) transcription factor. Overexpression of either I kappa B or the IRF-2 repressor was able to abrogate inducibility of the IFN-beta promoter. Thus, multiple regulatory events--including differential activation of DNA-binding NF-kappa B heterodimers, degradation of I kappa B alpha, synergistic interaction between IRF-1 and NF-kappa B, and decreased repression by I kappa B and IRF-2--are all required for the transcriptional activation of the IFN-beta promoter.

• Authors: E Garoufalis, I Kwan, R Lin, A Mustafa, N Pepin, A Roulston, J Lacoste, J Hiscott
• Journal: Journal of virology (J Virol) Vol. 68 Issue 8 Pg. 4707-15 (Aug 1994) ISSN: 0022-538X [Print] United States
• PMID: 8035474 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• NF-kappa B
• Proto-Oncogene Proteins
• Proto-Oncogene Proteins c-rel
• Interferon-beta
• DNA

Topics

• Animals
• Base Sequence
• Cells, Cultured
• DNA
• Gene Expression
• Humans
• Interferon-beta (genetics)
• Molecular Sequence Data
• NF-kappa B (metabolism)
• Parainfluenza Virus 1, Human (physiology)
• Polymerase Chain Reaction
• Promoter Regions, Genetic
• Proto-Oncogene Proteins (metabolism)
• Proto-Oncogene Proteins c-rel
• Regulatory Sequences, Nucleic Acid
• Transcription, Genetic
• Virus Replication