Chromatin Remodeling at DNA Double-Strand Breaks

DNA double-strand breaks (DSBs) can arise from multiple sources, including exposure to ionizing radiation. The repair of DSBs involves both post-translational modification of nucleosomes and concentration of DNA repair proteins at the site of damage. Consequently, nucleosome packing and chromatin architecture surrounding the DSB may limit the ability of the DNA damage response to access and repair the break. Here, we review early chromatin-based events that promote the formation of open, relaxed chromatin structures at DSBs and which allow the DNA repair machinery to access the spatially confined region surrounding the DSB, thereby facilitating mammalian DSB repair.