MacroH2A1 and ATM Play Opposing Roles in Paracrine Senescence and the Senescence-Associated Secretory Phenotype

Mol Cell. 2015 Sep 3;59(5):719-31. doi: 10.1016/j.molcel.2015.07.011. Epub 2015 Aug 20.

Abstract

Oncogene-induced senescence (OIS) is a tumor-suppressive mechanism typified by stable proliferative arrest, a persistent DNA damage response, and the senescence-associated secretory phenotype (SASP), which helps to maintain the senescent state and triggers bystander senescence in a paracrine fashion. Here, we demonstrate that the tumor suppressive histone variant macroH2A1 is a critical component of the positive feedback loop that maintains SASP gene expression and triggers the induction of paracrine senescence. MacroH2A1 undergoes dramatic genome-wide relocalization during OIS, including its removal from SASP gene chromatin. The removal of macroH2A1 from SASP genes results from a negative feedback loop activated by SASP-mediated endoplasmic reticulum (ER) stress. ER stress leads to increased reactive oxygen species and persistent DNA damage response including activation of ATM, which mediates removal macroH2A1 from SASP genes. Together, our findings indicate that macroH2A1 is a critical control point for the regulation of SASP gene expression during senescence.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Ataxia Telangiectasia Mutated Proteins / genetics*
  • Ataxia Telangiectasia Mutated Proteins / metabolism*
  • Cell Line
  • Cellular Senescence / genetics*
  • Cellular Senescence / physiology*
  • DNA Damage
  • Endoplasmic Reticulum Stress
  • Feedback, Physiological
  • Gene Expression Regulation
  • Histones / genetics*
  • Histones / metabolism*
  • Humans
  • Models, Biological
  • Oncogenes
  • Paracrine Communication
  • Phenotype

Substances

  • Histones
  • macroH2A histone
  • ATM protein, human
  • Ataxia Telangiectasia Mutated Proteins