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arXiv · 2606.16803

Cell Division Changes Fate Decisions in a Genetic Toggle Switch

Charli Austin·Nikola Popovic·Ramon Grima
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Abstract

Gene regulatory networks govern cellular fate decisions through multistable dynamics. The genetic toggle switch is a canonical model of such behaviour; yet, the impact of cell division on its dynamics remains poorly understood. We derive analytical separatrices for a simplified Boolean toggle switch with and without division. We show that division can redirect trajectories with identical initial conditions to opposing stable states, and we define a region of disagreement where fate decisions are predicted incorrectly if division is neglected. Our results imply that division can fundamentally reshape fate boundaries in multistable regulatory networks.

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Charli Austin, Nikola Popovic, Ramon Grima. 2026-06-15. Cell Division Changes Fate Decisions in a Genetic Toggle Switch. https://arxiv.org/abs/2606.16803

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