Systematic identification of functional residues in mammalian histone H2AX.

Chen WT, Alpert A, Leiter C, Gong F, Jackson SP, Miller KM

The histone variant H2AX is a principal component of chromatin involved in the detection, signaling and repair of DNA double-strand breaks (DSBs). H2AX is thought to operate primarily through its C-terminal S139 phosphorylation, which mediates the recruitment of DNA damage response (DDR) factors to chromatin at DSB sites. Here, we describe a comprehensive screen of 67 residues in H2AX to determine their contributions to H2AX functions. Our analysis revealed that H2AX is both sumoylated and ubiquitylated. Individual residues defective for sumoylation, ubiquitylation and S139 phosphorylation in untreated and damaged cells were identified. Specifically, we identified an acidic triad region in both H2A and H2AX that is required in cis for their ubiquitylation. We also report the characterization of a human H2AX knock-out cell line, which exhibits DDR defects, including p53 activation, following DNA damage. Collectively, this work constitutes the first genetic complementation system for a histone in human cells. Finally, our data reveal new roles for several residues in H2AX and define distinct functions for H2AX in human cells.

Cell Lysis
Western Blot
Bioruptor Plus

Share this article

October, 2012



  • APHL 2024
    Milwaukee, Wisconsin, USA
    May 6-May 9, 2024
 See all events


 See all news

The European Regional Development Fund and Wallonia are investing in your future.

Extension of industrial buildings and new laboratories.

       Site map   |   Contact us   |   Conditions of sales   |   Conditions of purchase   |   Privacy policy   |   Diagenode Diagnostics