title: Escape from transcriptional shutoff during poliovirus infection: NF-κB-responsive genes IκBa and A20.
abstract: It has been known for a long time that infection of cultured cells with poliovirus results in the overall inhibition of transcription of most host genes. We examined whether selected host genes can escape transcriptional inhibition by thiouridine marking newly synthesized host mRNAs during viral infection. Using cDNA microarrays hybridized to cDNAs made from thiolated mRNAs, a small set of host transcripts was identified and their expression verified by quantitative PCR and Northern and Western blot analyses. These transcripts were synthesized from genes that displayed enrichment for NF-κB binding sites in their promoter regions, suggesting that some NF-κB-regulated promoters can escape the virus-induced inhibition of transcription. In particular, two negative regulators of NF-κB, IκBa and A20, were upregulated during viral infection. Depletion of A20 enhanced viral RNA abundance and viral yield, arguing that cells respond to virus infection by counteracting NF-κB-induced proviral effects.
authors.affiliation: Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA, USA.
authors.forename: Tammy
authors.initials: T
authors.lastname: Doukas
authors.forename: Peter
authors.initials: P
authors.lastname: Sarnow
mesh_terms: D015152:Blotting, Northern; D015153:Blotting, Western; D004268:DNA-Binding Proteins; D020869:Gene Expression Profiling; D006367:HeLa Cells; D054884:Host-Pathogen Interactions; D006801:Humans; D020672:I-kappa B Proteins / Q000378:metabolism*; D057131:Immune Evasion; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism*; D046228:Microarray Analysis; D000072000:NF-KappaB Inhibitor alpha; D016328:NF-kappa B / Q000037:antagonists & inhibitors; D009687:Nuclear Proteins / Q000378:metabolism*; D017955:Poliovirus / Q000502:physiology*; D014176:Protein Biosynthesis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014158:Transcription, Genetic; D000072598:Tumor Necrosis Factor alpha-Induced Protein 3
chemical_list: D004268:DNA-Binding Proteins; D020672:I-kappa B Proteins; D047908:Intracellular Signaling Peptides and Proteins; D016328:NF-kappa B; C000606204:NFKBIA protein, human; D009687:Nuclear Proteins; D000072000:NF-KappaB Inhibitor alpha; C076529:TNFAIP3 protein, human; D000072598:Tumor Necrosis Factor alpha-Induced Protein 3