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Rapid Optimization of a Light-Inducible System to Control Mammalian Gene Expression
Published on: November 4, 2025
From dusk till dawn: one-plasmid systems for light-regulated gene expression
Robert Ohlendorf1, Roee R Vidavski, Avigdor Eldar
1Humboldt-Universität zu Berlin, Institut für Biologie, Biophysikalische Chemie, Invalidenstraße 42, 10115 Berlin, Germany.
Journal of Molecular Biology
|January 17, 2012
Summary
Researchers developed novel optogenetic tools, pDusk and pDawn, using blue-light photoreceptors for precise control of gene expression in E. coli. These systems offer light-activated or light-repressed gene expression with high efficiency and spatial control.
Area of Science:
- Molecular Biology
- Synthetic Biology
- Microbiology
Background:
- Signaling photoreceptors are crucial for light-mediated adaptations.
- Optogenetics utilizes light-gated proteins to control biological functions.
- Existing optogenetic tools have limitations in precision and efficiency.
Purpose of the Study:
- To develop novel, efficient optogenetic tools for gene expression control in E. coli.
- To create systems enabling both light-induced and light-repressed gene expression.
- To provide tools for network analysis and scalable protein production.
Main Methods:
- Engineered plasmids (pDusk and pDawn) utilizing blue-light photoreceptors.
- Demonstrated light-repressed and light-induced gene expression in Escherichia coli.
- Assessed system performance including dynamic range, background activity, and spatial resolution.
Main Results:
- Achieved up to 460-fold gene expression induction upon illumination.
- Demonstrated low background activity and high dynamic range.
- Showcased spatial control on the 20-μm scale and ease of use.
Conclusions:
- pDusk and pDawn are versatile optogenetic tools for precise gene expression control.
- These systems facilitate network interrogation and scalable recombinant protein production.
- The tools offer a cost-effective and automatable alternative to conventional induction methods.
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