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bioRxiv · 10.1101/2020.07.27.223131

Poly(ADP-ribose)-binding and macroH2A mediate recruitment and functions of KDM5A at DNA lesions

Abstract

The histone demethylase KDM5A removes histone H3 lysine 4 methylation, which is involved in transcription and DNA damage responses (DDR). While DDR functions of KDM5A have been identified, how KDM5A recognizes DNA lesion sites within chromatin is unknown. Here, we identify two factors that act upstream of KDM5A to promote its association with DNA damage sites. We have identified a non-canonical poly(ADP-ribose), (PAR), binding region unique to KDM5A. Loss of the PAR-binding region or treatment with PAR polymerase (PARP) inhibitors (PARPi) blocks KDM5A-PAR interactions and DNA repair functions of KDM5A. The histone variant macroH2A1.2 is also specifically required for KDM5A recruitment and functions at DNA damage sites, including homology-directed repair of DNA double-strand breaks and repression of transcription at DNA breaks. Overall, this work reveals the importance of PAR-binding and macroH2A1.2 in KDM5A recognition of damage sites that drive transcriptional and repair activities at DNA breaks within chromatin that are essential for maintaining genome integrity. SummaryThe histone demethylase KDM5A demethylates H3K4 to promote repair and transcriptional responses at DNA breaks. We identified poly(ADP-ribose)-binding and macroH2A1.2 as modulators of KDM5A association with DNA damage sites, revealing how KDM5A engages DNA breaks within chromatin.

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BibTeXRIS

Kumbhar, R. R., Perren, J., Gong, F., Corujo, D., Medina, F., Matouschek, A., Buschbeck, M., Miller, K. M.. 2020-07-28. Poly(ADP-ribose)-binding and macroH2A mediate recruitment and functions of KDM5A at DNA lesions. https://doi.org/10.1101/2020.07.27.223131

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