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arXiv · 2401.06674

Confinement determines transport of a reaction-diffusion active matter front

Nicolas Lobato-Dauzier·Ananyo Maitra·André Estevez-Torres·Jean-Christophe Galas
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Abstract

Couplings between biochemical and mechanical processes have a profound impact on embryonic development. However, in-vitro studies capable of quantifying these interactions have remained elusive. Here, we investigate a synthetic system where a DNA reaction-diffusion (RD) front is advected by a turbulent flow generated by active matter (AM) flows in a quasi-one-dimensional geometry. Whereas the dynamics of simple RD fronts solely depend on the reaction and diffusion rates, we show that RD-AM front propagation is also influenced by the confinement geometry. We first experimentally dissected the different components of the reaction-diffusion-advection process by knocking out reaction or advection and observed how RD-AM allows for faster transport over large distances, avoiding dilution. We then show how confinement impacts active matter flow: while changes in instantaneous flow velocities are small; correlation times are dramatically increased with decreasing confinement. As a result, RD-AM front speed increased up to 8-fold compared to a RD one, in quantitative agreement with a conveyor belt RDA theoretical model. The RD-AM experimental system described here provides a framework for the rational engineering of complex spatiotemporal processes observed in living systems. It will reinforce our understanding of how macro-scale patterns and structures emerge from microscopic components in non-equilibrium systems.

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Nicolas Lobato-Dauzier, Ananyo Maitra, André Estevez-Torres, Jean-Christophe Galas. 2024-01-12. Confinement determines transport of a reaction-diffusion active matter front. https://arxiv.org/abs/2401.06674

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