DNA damage induces reactive oxygen species generation through the H2AX-Nox1/Rac1 pathway

Cell Death Dis. 2012 Jan 12;3(1):e249. doi: 10.1038/cddis.2011.134.

Abstract

The DNA damage response (DDR) cascade and ROS (reactive oxygen species) signaling are both involved in the induction of cell death after DNA damage, but a mechanistic link between these two pathways has not been clearly elucidated. This study demonstrates that ROS induction after treatment of cells with neocarzinostatin (NCS), an ionizing radiation mimetic, is at least partly mediated by increasing histone H2AX. Increased levels of ROS and cell death induced by H2AX overexpression alone or DNA damage leading to H2AX accumulation are reduced by treating cells with the antioxidant N-Acetyl-L-Cysteine (NAC), the NADP(H) oxidase (Nox) inhibitor DPI, expression of Rac1N17, and knockdown of Nox1, but not Nox4, indicating that induction of ROS by H2AX is mediated through Nox1 and Rac1 GTPase. H2AX increases Nox1 activity partly by reducing the interaction between a Nox1 activator NOXA1 and its inhibitor 14-3-3zeta. These results point to a novel role of histone H2AX that regulates Nox1-mediated ROS generation after DNA damage.

Publication types

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

MeSH terms

  • 14-3-3 Proteins / genetics
  • 14-3-3 Proteins / metabolism
  • Acetylcysteine / pharmacology
  • Adaptor Proteins, Signal Transducing
  • Adaptor Proteins, Vesicular Transport / antagonists & inhibitors
  • Adaptor Proteins, Vesicular Transport / genetics
  • Adaptor Proteins, Vesicular Transport / metabolism
  • Antioxidants / pharmacology
  • Cell Death
  • Cell Line, Tumor
  • Cytotoxins / toxicity
  • DNA Damage
  • Flow Cytometry
  • Gene Expression / drug effects*
  • Histones / genetics
  • Histones / metabolism*
  • Humans
  • NADPH Oxidase 1
  • NADPH Oxidases / antagonists & inhibitors
  • NADPH Oxidases / genetics
  • NADPH Oxidases / metabolism
  • Phosphorylation
  • Plasmids
  • Reactive Oxygen Species / metabolism
  • Signal Transduction / drug effects
  • Signal Transduction / genetics*
  • Transfection
  • Zinostatin / toxicity*
  • rac1 GTP-Binding Protein / genetics
  • rac1 GTP-Binding Protein / metabolism*

Substances

  • 14-3-3 Proteins
  • Adaptor Proteins, Signal Transducing
  • Adaptor Proteins, Vesicular Transport
  • Antioxidants
  • Cytotoxins
  • H2AX protein, human
  • Histones
  • NOXA1 protein, human
  • RAC1 protein, human
  • Reactive Oxygen Species
  • Zinostatin
  • NADPH Oxidase 1
  • NADPH Oxidases
  • NOX1 protein, human
  • rac1 GTP-Binding Protein
  • Acetylcysteine