Evidence for postinitiation regulation of mRNA biogenesis in tuberculosis

J Immunol. 2013 Mar 15;190(6):2747-55. doi: 10.4049/jimmunol.1202185. Epub 2013 Feb 1.

Abstract

Mycobacterium tuberculosis infection alters macrophage gene expression and macrophage response to IFN-γ, a critical host defense cytokine. However, regulation of these changes is poorly understood. We report discordance of changes in nascent transcript and total nuclear RNA abundance for the transcription factors STAT1 and IRF1, together with lack of effect on their RNA half-lives, in human THP-1 cells infected with M. tuberculosis and stimulated with IFN-γ. The results indicate that negative postinitiation regulation of mRNA biogenesis limits the expression of these factors, which mediate host defense against M. tuberculosis through the cellular response to IFN-γ. Consistent with the results for STAT1 and IRF1, transcriptome analysis reveals downregulation of postinitiation mRNA biogenesis processes and pathways by infection, with and without IFN-γ stimulation. Clinical relevance for regulation of postinitiation mRNA biogenesis is demonstrated by studies of donor samples showing that postinitiation mRNA biogenesis pathways are repressed in latent tuberculosis infection compared with cured disease and in active tuberculosis compared with ongoing treatment or with latent tuberculosis. For active disease and latent infection donors from two populations (London, U.K., and The Gambia), each analyzed using a different platform, pathway-related gene expression differences were highly correlated, demonstrating substantial specificity in the effect. Collectively, the molecular and bioinformatic analyses point toward downregulation of postinitiation mRNA biogenesis pathways as a means by which M. tuberculosis infection limits expression of immunologically essential transcription factors. Thus, negative regulation of postinitiation mRNA biogenesis can constrain the macrophage response to infection and overall host defense against tuberculosis.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Line
  • Down-Regulation / genetics
  • Down-Regulation / immunology*
  • Humans
  • Interferon Regulatory Factor-1 / biosynthesis
  • Interferon Regulatory Factor-1 / genetics
  • Interferon-gamma / physiology
  • Latent Tuberculosis / genetics
  • Latent Tuberculosis / immunology
  • Latent Tuberculosis / metabolism
  • Macrophages, Alveolar / immunology
  • Macrophages, Alveolar / microbiology
  • Macrophages, Alveolar / pathology
  • Mycobacterium tuberculosis / immunology
  • RNA, Messenger / antagonists & inhibitors*
  • RNA, Messenger / biosynthesis*
  • STAT1 Transcription Factor / biosynthesis
  • STAT1 Transcription Factor / genetics
  • Signal Transduction / genetics
  • Signal Transduction / immunology
  • Transcriptional Activation / genetics
  • Transcriptional Activation / immunology
  • Tuberculosis, Pulmonary / genetics*
  • Tuberculosis, Pulmonary / immunology*
  • Tuberculosis, Pulmonary / metabolism

Substances

  • IRF1 protein, human
  • Interferon Regulatory Factor-1
  • RNA, Messenger
  • STAT1 Transcription Factor
  • STAT1 protein, human
  • Interferon-gamma

Associated data

  • GEO/GSE17477