Coordinated changes in mRNA turnover, translation, and RNA processing bodies in bronchial epithelial cells following inflammatory stimulation

Mol Cell Biol. 2008 Dec;28(24):7414-26. doi: 10.1128/MCB.01237-08. Epub 2008 Oct 20.

Abstract

Bronchial epithelial cells play a pivotal role in airway inflammation, but little is known about posttranscriptional regulation of mediator gene expression during the inflammatory response in these cells. Here, we show that activation of human bronchial epithelial BEAS-2B cells by proinflammatory cytokines interleukin-4 (IL-4) and tumor necrosis factor alpha (TNF-alpha) leads to an increase in the mRNA stability of the key chemokines monocyte chemotactic protein 1 and IL-8, an elevation of the global translation rate, an increase in the levels of several proteins critical for translation, and a reduction of microRNA-mediated translational repression. Moreover, using the BEAS-2B cell system and a mouse model, we found that RNA processing bodies (P bodies), cytoplasmic domains linked to storage and/or degradation of translationally silenced mRNAs, are significantly reduced in activated bronchial epithelial cells, suggesting a physiological role for P bodies in airway inflammation. Our study reveals an orchestrated change among posttranscriptional mechanisms, which help sustain high levels of inflammatory mediator production in bronchial epithelium during the pathogenesis of inflammatory airway diseases.

Publication types

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

MeSH terms

  • Animals
  • Bronchi / cytology*
  • Cell Line
  • Chemokine CCL2 / genetics
  • Chemokine CCL2 / metabolism
  • Epithelial Cells / cytology
  • Epithelial Cells / physiology*
  • Gene Expression Regulation*
  • Humans
  • Inflammation / immunology*
  • Interleukin-4 / genetics
  • Interleukin-4 / metabolism
  • Interleukin-8 / genetics
  • Interleukin-8 / metabolism
  • Mice
  • MicroRNAs / genetics
  • MicroRNAs / metabolism
  • Protein Biosynthesis / physiology*
  • RNA Stability
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism*
  • RNA, Ribosomal / genetics
  • RNA, Ribosomal / metabolism
  • Tumor Necrosis Factor-alpha / genetics
  • Tumor Necrosis Factor-alpha / metabolism

Substances

  • Chemokine CCL2
  • Interleukin-8
  • MicroRNAs
  • RNA, Messenger
  • RNA, Ribosomal
  • Tumor Necrosis Factor-alpha
  • Interleukin-4