Evidence for IL-6 promoter nuclear activation in U937 cells stimulated with Salmonella enterica serovar Typhimurium porins

Eur Cytokine Netw. 2009 Sep;20(3):140-7. doi: 10.1684/ecn.2009.0158.

Abstract

Interleukin-6 (IL-6) is a pleiotropic cytokine and plays an active role in inflammatory and immune responses, contributing to a multitude of physiological and pathophysiological processes. In this study, we address the molecular mechanism of IL-6 transcriptional induction and propose a correlation between activated NF-kappaB localization and IL-6 expression. In particular, we detected, by ChIP assay, that occupation of the IL-6 gene promoter site is dependent on activated NF-kappaB. In fact, after porin stimulation, the NF-kappaB p65 subunit is activated, translocates to the nucleus and binds to the IL-6 promoter sequence.Elucidation of the host signaling pathways and identification of the transcription factors that contribute to IL-6 expression, may aid in the understanding of host susceptibility to gram-negative infections and in identifying new therapeutic strategies in a variety of infectious diseases.

MeSH terms

  • Cell Nucleus / genetics*
  • Consensus Sequence / genetics
  • Densitometry
  • Gene Expression Regulation, Neoplastic / drug effects
  • Humans
  • Interleukin-6 / genetics*
  • Interleukin-6 / metabolism
  • NF-kappa B / metabolism
  • Porins / pharmacology*
  • Promoter Regions, Genetic*
  • Protein Binding / drug effects
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Salmonella typhimurium / chemistry*
  • Signal Transduction / drug effects
  • U937 Cells

Substances

  • IL6 protein, human
  • Interleukin-6
  • NF-kappa B
  • Porins
  • RNA, Messenger