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bioRxiv · 10.1101/261610

Regulation of ATM and ATR by SMARCAL1 and BRG1

Sethy, R.·Rakesh, R.·Patne, K.·Arya, V.·Sharma, T.·Haokip, D.·Kumari, R.·Muthuswami, R.
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Abstract

The G2/M checkpoint is activated on DNA damage by the ATM and ATR kinases that are regulated by post-translational modifications. In this paper, the transcriptional co-regulation of ATM and ATR by SMARCAL1 and BRG1, both members of the ATP-dependent chromatin remodeling protein family, is described. SMARCAL1 and BRG1 co-localize on the promoters of ATM and ATR; downregulation of SMARCAL1/BRG1 results in transcriptional repression of ATM/ATR and therefore, overriding of the G2/M checkpoint leading to mitotic abnormalities. On doxorubicin-induced DNA damage, SMARCAL1 and BRG1 are upregulated and in turn, upregulate the expression of ATM/ATR.\n\nPhosphorylation of ATM/ATR is needed for the transcriptional upregulation of SMARCAL1 and BRG1, and therefore, of ATM and ATR on DNA damage. The regulation of ATM/ATR is rendered non-functional if SMARCAL1 and/or BRG1 are absent or if the two proteins are mutated such that they are unable to hydrolyze ATP, as in for example in Schimke Immuno-Osseous Dysplasia and Coffin-Siris Syndrome. Thus, an intricate transcriptional regulation of DNA damage response genes mediated by SMARCAL1 and BRG1 is present in mammalian cells.

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Sethy, R., Rakesh, R., Patne, K., Arya, V., Sharma, T., Haokip, D., Kumari, R., Muthuswami, R.. 2018-02-08. Regulation of ATM and ATR by SMARCAL1 and BRG1. https://doi.org/10.1101/261610

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