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bioRxiv · 10.1101/2025.11.24.690157

Stochastic Gene Expression under Sequestration: Noise Reduction and Emergent Distributions

Morozova, O.·Oravcova, I.·Zabaikina, I.·Bokes, P.·Singh, A.
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Abstract

Gene expression noise can be modulated by protein sequestration, a mechanism we investigate through a stochastic modeling framework. We examine how the distribution of free (non-sequestered) protein depends on sequestration cooperativity (monomers, dimers, multimers) and on the timescale separation between sequestration and protein turnover. For non-cooperative sequestration, faster kinetics drive the distribution from a high-noise to a lower-noise gamma form, while the right-tail remains governed by the high-noise limit -- revealing a non-commutativity between tail asymptotics and fast sequestration. For cooperative sequestration, the distribution departs from gamma, exhibiting left skewness or multi-modality. These results highlight how sequestration mechanisms shape protein variability in nontrivial ways.

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Morozova, O., Oravcova, I., Zabaikina, I., Bokes, P., Singh, A.. 2025-11-26. Stochastic Gene Expression under Sequestration: Noise Reduction and Emergent Distributions. https://doi.org/10.1101/2025.11.24.690157

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