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bioRxiv · 10.1101/2021.04.20.440667

A push-pull system of repressors matches levels of glucose transporters to extracellular glucose in budding yeast

Montano-Gutierrez, L. F.·Sturrock, M.·Farquhar, I. L.·Correia, K.·Shahrezaei, V.·Swain, P. S.
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Abstract

A common cellular task is to match gene expression dynamically to a range of concentrations of a regulatory molecule. Studying glucose transport in budding yeast, we determine mechanistically how such matching occurs for seven hexose transporters. By combining time-lapse microscopy with mathematical modelling, we find that levels of transporters are history-dependent and are regulated by a push-pull system comprising two types of repressors. Repression by these two types varies with glucose in opposite ways, and not only matches the expression of transporters by their affinity to a range of glucose concentrations, but also the expression of some to how glucose is changing. We argue that matching is favoured by a rate-affinity trade-off and that the regulatory system allows yeast to import glucose rapidly enough to starve competitors. Matching expression to a pattern of input is fundamental, and we believe that push-pull repression is widespread.

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Montano-Gutierrez, L. F., Sturrock, M., Farquhar, I. L., Correia, K., Shahrezaei, V., Swain, P. S.. 2021-04-21. A push-pull system of repressors matches levels of glucose transporters to extracellular glucose in budding yeast. https://doi.org/10.1101/2021.04.20.440667

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