DNA double-stranded breaks induce histone H2AX phosphorylation on serine 139

J Biol Chem. 1998 Mar 6;273(10):5858-68. doi: 10.1074/jbc.273.10.5858.


When mammalian cell cultures or mice are exposed to ionizing radiation in survivable or lethal amounts, novel mass components are found in the histone H2A region of two-dimensional gels. Collectively referred to as gamma, these components are formed in vivo by several procedures that introduce double-stranded breaks into DNA. gamma-Components, which appeared to be the only major novel components detected by mass or 32PO4 incorporation on acetic acid-urea-Triton X-100-acetic acid-urea-cetyltrimethylammonium bromide or SDS-acetic acid-urea-cetyltrimethylammonium bromide gels after exposure of cells to ionizing radiation, are shown to be histone H2AX species that have been phosphorylated specifically at serine 139. gamma-H2AX appears rapidly after exposure of cell cultures to ionizing radiation; half-maximal amounts are reached by 1 min and maximal amounts by 10 min. At the maximum, approximately 1% of the H2AX becomes gamma-phosphorylated per gray of ionizing radiation, a finding that indicates that 35 DNA double-stranded breaks, the number introduced by each gray into the 6 x 10(9) base pairs of a mammalian G1 genome, leads to the gamma-phosphorylation of H2AX distributed over 1% of the chromatin. Thus, about 0.03% of the chromatin appears to be involved per DNA double-stranded break. This value, which corresponds to about 2 x 10(6) base pairs of DNA per double-stranded break, indicates that large amounts of chromatin are involved with each DNA double-stranded break. Thus, gamma-H2AX formation is a rapid and sensitive cellular response to the presence of DNA double-stranded breaks, a response that may provide insight into higher order chromatin structures.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Cells, Cultured
  • Chromatin / metabolism
  • DNA / radiation effects*
  • Electrophoresis, Gel, Two-Dimensional
  • Gamma Rays*
  • Histones / metabolism*
  • Mice
  • Mice, Inbred Strains
  • Molecular Sequence Data
  • Nuclear Proteins / metabolism
  • Peptide Fragments / chemistry
  • Phosphorylation
  • Phosphoserine / analysis
  • Protein Kinases / metabolism
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / genetics
  • Whole-Body Irradiation


  • Chromatin
  • Histones
  • Nuclear Proteins
  • Peptide Fragments
  • Recombinant Proteins
  • Phosphoserine
  • DNA
  • Protein Kinases