Histone code

Gene

Epigenome

Epigenomics

DNA repair

DNA damage

Gene expression

Chromatin remodeling

DNA methylation

Genetics

Histone H2A

Histone-modifying enzymes

Histone

Computational biology

Chromatin

Nucleosome

Biology

Cell biology

Molecular Cell

Highlights•Parental H3 histones redistribute to the periphery of UVC-damaged regions•The redistribution involves histone mobilization on chromatin and chromatin opening•Parental histones recover massively during repair progression•Parental histone dynamics may help coordinate DNA repair with epigenome integritySummaryChromatin integrity is critical for cell function and identity but is challenged by DNA damage. To understand how chromatin architecture and the information that it conveys are preserved or altered following genotoxic stress, we established a system for real-time tracking of parental histones, which characterize the pre-damage chromatin state. Focusing on histone H3 dynamics after local UVC irradiation in human cells, we demonstrate that parental histones rapidly redistribute around damaged regions by a dual mechanism combining chromatin opening and histone mobilization on chromatin. Importantly, parental histones almost entirely recover and mix with new histones in repairing chromatin. Our data further define a close coordination of parental histone dynamics with DNA repair progression through the damage sensor DDB2 (DNA damage-binding protein 2). We speculate that this mechanism may contribute to maintaining a memory of the original chromatin landscape and may help preserve epigenome stability in response to DNA damage.Graphical abstract

Real-Time Tracking of Parental Histones Reveals Their Contribution to Chromatin Integrity Following DNA Damage