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arXiv · 1904.11310

Transcriptional bursts in a non-equilibrium model for gene regulation by supercoiling

Marco Ancona·Alessandro Bentivoglio·Chris A. Brackley·Giuseppe Gonnella·Davide Marenduzzo
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Abstract

We analyse transcriptional bursting within a stochastic non-equilibrium model which accounts for the coupling between the dynamics of DNA supercoiling and gene transcription. We find a clear signature of bursty transcription when there is a separation between the timescales of transcription initiation and supercoiling dissipation - the latter may either be diffusive or mediated by topological enzymes, such as type I or type II topoisomerases. In multigenic DNA domains we observe either bursty transcription, or transcription waves; the type of behaviour can be selected for by controlling gene activity and orientation. In the bursty phase, the statistics of supercoiling fluctuations at the promoter are markedly non-Gaussian.

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Marco Ancona, Alessandro Bentivoglio, Chris A. Brackley, Giuseppe Gonnella, Davide Marenduzzo. 2019-04-25. Transcriptional bursts in a non-equilibrium model for gene regulation by supercoiling. https://doi.org/10.1016/j.bpj.2019.04.023

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