Synergistic gene expression during the acute phase response is characterized by transcription factor assisted loading

Nat Commun. 2017 Nov 29;8(1):1849. doi: 10.1038/s41467-017-02055-5.

Abstract

The cytokines interleukin 1β and 6 (IL-1β, IL-6) mediate the acute phase response (APR). In liver, they regulate the secretion of acute phase proteins. Using RNA-seq in primary hepatocytes, we show that these cytokines regulate transcription in a bifurcated manner, leading to both synergistic and antagonistic gene expression. By mapping changes in enhancer landscape and transcription factor occupancy (using ChIP-seq), we show that synergistic gene induction is achieved by assisted loading of STAT3 on chromatin by NF-κB. With IL-6 treatment alone, STAT3 does not efficiently bind 20% of its coordinated binding sites. In the presence of IL-1β, NF-κB is activated, binds a subset of enhancers and primes their activity, as evidenced by increasing H3K27ac. This facilitates STAT3 binding and synergistic gene expression. Our findings reveal an enhancer-specific crosstalk whereby NF-κB enables STAT3 binding at some enhancers while perturbing it at others. This model reconciles seemingly contradictory reports of NF-κB-STAT3 crosstalk.

Publication types

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

MeSH terms

  • Acute-Phase Reaction / genetics*
  • Animals
  • Binding Sites
  • Cells, Cultured
  • Chromatin Immunoprecipitation
  • Enhancer Elements, Genetic
  • Gene Expression Regulation / drug effects
  • Hepatocytes / drug effects
  • Hepatocytes / physiology*
  • Interleukin-1beta / pharmacology
  • Interleukin-6 / pharmacology
  • Male
  • Mice, Inbred C57BL
  • NF-kappa B / genetics
  • NF-kappa B / metabolism
  • RNA Polymerase II / genetics
  • RNA Polymerase II / metabolism
  • STAT3 Transcription Factor / genetics
  • STAT3 Transcription Factor / metabolism
  • Transcription Factors / genetics
  • Transcription Factors / metabolism*

Substances

  • Interleukin-1beta
  • Interleukin-6
  • NF-kappa B
  • STAT3 Transcription Factor
  • Stat3 protein, mouse
  • Transcription Factors
  • RNA Polymerase II