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bioRxiv · 10.1101/2024.09.17.613456

Metabolite-responsive Control of Transcription by Phase Separation-based Synthetic Organelles

Jerez-Longres, C.·Weber, W.
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Abstract

Living natural materials have remarkable sensing abilities that translate external cues into functional changes of the material. The reconstruction of such sensing materials in bottom-up synthetic biology provides the opportunity to develop synthetic materials with life-like sensing and adaptation ability. Key to such functions are material modules that translate specific input signals into a biomolecular response. Here, we engineer a synthetic organelle based on liquid-liquid phase separation that translates a metabolic signal into the regulation of gene transcription. To this aim, we engineer the pyruvate-dependent repressor PdhR to undergo liquid-liquid phase separation in vitro by fusion to intrinsically disordered regions. We demonstrate that the resulting coacervates bind DNA harbouring PdhR-responsive operator sites in a pyruvate dose-dependent and reversible manner. We observed that the activity of transcription units on the DNA was strongly attenuated following recruitment to the coacervates. However, the addition of pyruvate resulted in a reversible and dose-dependent reconstitution of transcriptional activity. The coacervate-based synthetic organelles linking metabolic cues to transcriptional signals represent a materials approach to confer stimulus-responsiveness to minimal bottom-up synthetic biological systems and open opportunities in materials for sensor applications.

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Jerez-Longres, C., Weber, W.. 2024-09-17. Metabolite-responsive Control of Transcription by Phase Separation-based Synthetic Organelles. https://doi.org/10.1101/2024.09.17.613456

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