Viscoadaptation controls intracellular reaction rates in response to heat and energy availability

Persson, L.; Ambati, V. S.; Brandman, O.

doi:10.1101/709717

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bioRxiv · 10.1101/709717

Viscoadaptation controls intracellular reaction rates in response to heat and energy availability

Persson, L.·Ambati, V. S.·Brandman, O.

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Abstract

Summary/AbstractCells must precisely orchestrate thousands of reactions in both time and space. Yet reaction kinetics are highly dependent on uncontrollable environmental conditions such as temperature. Here, we report a novel mechanism by which budding yeast influence reaction rates through adjustment of intracellular viscosity. This \"viscoadaptation\" is achieved by production of two carbohydrates, trehalose and glycogen, which combine to create a more viscous cellular environment in which biomolecules retain solubility. We demonstrate that viscoadaptation functions as both an acute response to temperature increase as well as a homeostatic mechanism, allowing cells grown at temperatures spanning from 22{degrees}C to 40{degrees}C to maintain equivalent rates of intracellular diffusion and diffusion-controlled chemical reactions. Multiple conditions that lower ATP trigger viscoadaptation, suggesting that viscoadaptation may be a general cellular response to low energy. Viscoadaptation reveals viscosity to be a tunable property of cells through which they can regulate diffusion-controlled processes dynamically in response to a changing environment.

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Persson, L., Ambati, V. S., Brandman, O.. 2019-07-21. Viscoadaptation controls intracellular reaction rates in response to heat and energy availability. https://doi.org/10.1101/709717

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