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Light-Dependent Control of Bacterial Expression at the mRNA Level
Américo T Ranzani1, Markus Wehrmann1, Jennifer Kaiser1
1Department of Biochemistry, University of Bayreuth, 95447 Bayreuth, Germany.
ACS Synthetic Biology
|September 21, 2022
Summary
Researchers developed new optogenetic systems, pCrepusculo and pAurora, for precise control of bacterial gene expression using blue light. These systems leverage the light-oxygen-voltage receptor (PAL) and RNA aptamers for light-induced gene regulation.
Area of Science:
- Synthetic Biology
- Optogenetics
- Molecular Biology
Background:
- Photoreceptors enable light-controlled cellular processes in optogenetics.
- The light-oxygen-voltage (LOV) receptor PAL interacts with RNA aptamers upon blue-light illumination.
Purpose of the Study:
- To develop novel optogenetic systems for precise up- and down-regulation of bacterial gene expression using blue light.
- To create compact, single-plasmid systems with high dynamic range and low basal activity.
Main Methods:
- Development of pCrepusculo and pAurora systems based on the PAL-aptamer interaction.
- Embedding responsive aptamers within the ribosome-binding sequence of target genes.
- Integration of RNA-level control with DNA-level regulatory mechanisms.
Main Results:
- Demonstrated blue-light-inducible downregulation (pCrepusculo) and upregulation (pAurora) of gene expression.
- Achieved stringent blue-light responses with low basal activity and up to 10-fold dynamic range.
- Engineered the pEnumbra system for tunable gene expression (upregulation and shutoff) based on blue-light intensity.
Conclusions:
- The PAL-aptamer system offers a versatile tool for light-controlled gene expression in bacteria.
- These systems enable the design of complex optogenetic circuits with emergent properties by combining DNA and RNA regulation.
- The developed systems have broad applications in biotechnology and synthetic biology for controlling RNA-based processes.
Keywords:
RNA bindinggene expressionlight-oxygen-voltageoptogeneticssensory photoreceptortranslational controlMore Related Videos
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