High rates of fuel consumption are not required by insulating motifs to suppress retroactivity in biochemical circuits

Abhishek Deshpande; Thomas E. Ouldridge

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arXiv · 1708.01792

High rates of fuel consumption are not required by insulating motifs to suppress retroactivity in biochemical circuits

Abhishek Deshpande·Thomas E. Ouldridge

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Abstract

Retroactivity arises when the coupling of a molecular network $\mathcal{U}$ to a downstream network $\mathcal{D}$ results in signal propagation back from $\mathcal{D}$ to $\mathcal{U}$. The phenomenon represents a breakdown in modularity of biochemical circuits and hampers the rational design of complex functional networks. Considering simple models of signal-transduction architectures, we demonstrate the strong dependence of retroactivity on the properties of the upstream system, and explore the cost and efficacy of fuel-consuming insulating motifs that can mitigate retroactive effects. We find that simple insulating motifs can suppress retroactivity at a low fuel cost by coupling only weakly to the upstream system $\mathcal{U}$. However, this design approach reduces the signalling network's robustness to perturbations from leak reactions, and potentially compromises its ability to respond to rapidly-varying signals.

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Abhishek Deshpande, Thomas E. Ouldridge. 2017-08-05. High rates of fuel consumption are not required by insulating motifs to suppress retroactivity in biochemical circuits. https://arxiv.org/abs/1708.01792

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