Polyclonal Antibody to Histone H2A.X (Phospho-Ser139)

Variant histone H2A which replaces conventional H2A in a subset of nucleosomes. Nucleosomes wrap and compact DNA into chromatin, limiting DNA accessibility to the cellular machineries which require DNA as a template. Histones thereby play a central role in transcription regulation, DNA repair, DNA replication and chromosomal stability. DNA accessibility is regulated via a complex set of post-translational modifications of histones, also called histone code, and nucleosome remodeling. Required for checkpoint-mediated arrest of cell cycle progression in response to low doses of ionizing radiation and for efficient repair of DNA double strand breaks (DSBs) specifically when modified by C-terminal phosphorylation. Yaneva M, et al. (2005) Nucleic Acids Res. 33 (16) : 5320-5330. Tsukuda T, et al. (2006) Nature. Author manuscript; available in PMC 2006 March 6.