Epigenetic silencing of IRF1 dysregulates type III interferon responses to respiratory virus infection in epithelial to mesenchymal transition

Nat Microbiol. 2017 Jun 5:2:17086. doi: 10.1038/nmicrobiol.2017.86.

Abstract

Chronic oxidative injury produced by airway disease triggers a transforming growth factor-β (TGF-β)-mediated epigenetic reprogramming known as the epithelial-mesenchymal transition (EMT). We observe that EMT silences protective mucosal interferon (IFN)-I and III production associated with enhanced rhinovirus (RV) and respiratory syncytial virus (RSV) replication. Mesenchymal transitioned cells are defective in inducible interferon regulatory factor 1 (IRF1) expression by occluding RelA and IRF3 access to the promoter. IRF1 is necessary for the expression of type III IFNs (IFNLs 1 and 2/3). Induced by the EMT, zinc finger E-box binding homeobox 1 (ZEB1) binds and silences IRF1. Ectopic ZEB1 is sufficient for IRF1 silencing, whereas ZEB1 knockdown partially restores IRF1-IFNL upregulation. ZEB1 silences IRF1 through the catalytic activity of the enhancer of zeste 2 polycomb repressive complex 2 subunit (EZH2), forming repressive H3K27(me3) marks. We observe that IRF1 expression is mediated by ZEB1 de-repression, and our study demonstrates how airway remodelling/fibrosis is associated with a defective mucosal antiviral response through ZEB1-initiated epigenetic silencing.

MeSH terms

  • Antiviral Agents / metabolism
  • Cells, Cultured
  • Epigenesis, Genetic
  • Epithelial Cells / physiology
  • Epithelial Cells / virology
  • Epithelial-Mesenchymal Transition*
  • Gene Silencing*
  • Host-Pathogen Interactions*
  • Humans
  • Immune Evasion
  • Interferon Regulatory Factor-1 / biosynthesis*
  • Interferons / metabolism*
  • Respiratory Syncytial Viruses / physiology*
  • Zinc Finger E-box-Binding Homeobox 1 / metabolism*

Substances

  • Antiviral Agents
  • IRF1 protein, human
  • Interferon Regulatory Factor-1
  • ZEB1 protein, human
  • Zinc Finger E-box-Binding Homeobox 1
  • Interferons