The chromatin associated Sin3B is a critical regulator of DNA damage repair through the engagement of the Non-Homologous End Joining.

Morales-Valencia, J.; Calderon, A.; Saini, S.; David, G.

doi:10.1101/2022.03.09.483624

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bioRxiv · 10.1101/2022.03.09.483624

The chromatin associated Sin3B is a critical regulator of DNA damage repair through the engagement of the Non-Homologous End Joining.

Morales-Valencia, J.·Calderon, A.·Saini, S.·David, G.

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Abstract

Transcription and DNA damage repair act in a coordinated manner. The scaffolding protein Sin3B serves as a transcriptional corepressor of hundreds of cell-cycle-related genes. However, the role of Sin3B during the DNA damage response still remains unknown. Here, we show that Sin3B depletion delays the resolution of DNA double-strand breaks (DSBs) and sensitizes cells to diverse DNA-damaging agents, including cisplatin and doxorubicin. Furthermore, Sin3B is rapidly recruited to DNA damage sites and interacts with other DDR proteins. Mechanistically, Sin3B promotes non-homologous end joining DNA repair by directing the accumulation of MDC1 at DBSs. Altogether, our findings impute an unexpected function for the transcriptional co-repressor Sin3B as a gatekeeper of genomic integrity, and point to the inhibition of the Sin3B chromatin modifying complex as a novel therapeutic vulnerability in cancer cells.

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Morales-Valencia, J., Calderon, A., Saini, S., David, G.. 2022-03-11. The chromatin associated Sin3B is a critical regulator of DNA damage repair through the engagement of the Non-Homologous End Joining.. https://doi.org/10.1101/2022.03.09.483624

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