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Updated: Aug 17, 2026

Evaluation of the Spatial Distribution of γH2AX following Ionizing Radiation
Published on: August 7, 2010
Chromosome regions enriched in hyperacetylated histone H4 are preferred sites for endonuclease- and radiation-induced
W Martínez-López1, G A Folle, G Obe
1Faculty of Sciences, University of the Republic, Montevideo, Uruguay. wlopez@iibce.edu.uy
Abstract:
Previously, we have shown that breakpoints induced by the endonucleases AluI, BamHI and DNase I in CHO chromosomes are localized mainly in G-light bands. Neutrons and gamma rays produced similar breakpoint clusters to endonucleases in most CHO chromosomes. Here we compare endonuclease- and radiation-induced breakpoint maps with hyperacetylation patterns of histone H4. The H4 acetylation pattern in chromosomes is similar to the pattern of G-light, or R-bands, and breakpoints are clustered in highly acetylated chromosome regions. These findings indicate that chromosomal aberrations occur more frequently in active than in inactive chromatin.
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