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bioRxiv · 10.1101/2020.04.30.071282

Decoupling transcription factor expression and activity enables dimmer-switch gene regulation

Ricci-Tam, C.·Wang, J.·Ben-Zion, I.·Palme, J.·Li, A.·Savir, Y.·Springer, M.
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Abstract

Our mechanistic understanding of how gene regulatory networks can achieve complex biological responses is limited. We find that the galactose-responsive pathway in S. cerevisiae has a complex behavior - the decision to induce is controlled independently from the induction level, resembling a mechanical dimmer-switch. Surprisingly, this behavior is not achieved directly through chromatin regulation or combinatorial control at galactose-responsive promoters. Instead, this behavior is achieved by hierarchical regulation of the expression and catalytic activity of a single transcription factor. This genetic motif allows evolution to independently act on both properties, providing a means to tune both resource allocation strategies in dynamic multi-input environments on both physiological and evolutionary time-scales. Hierarchical regulation is ubiquitous and thus dimmer-switch regulation is likely a key feature of many biological systems.

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Ricci-Tam, C., Wang, J., Ben-Zion, I., Palme, J., Li, A., Savir, Y., Springer, M.. 2020-05-01. Decoupling transcription factor expression and activity enables dimmer-switch gene regulation. https://doi.org/10.1101/2020.04.30.071282

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