Highlighter: An optogenetic system for high-resolution gene expression control in plants

Area of Science:

• Plant Biology
• Synthetic Biology
• Optogenetics

Background:

• Optogenetics offers precise biological control but faces challenges in plants due to light environments and crosstalk with endogenous systems.
• Existing optogenetic tools often require external cofactors or interact with native plant signaling pathways.

Purpose of the Study:

• To develop a novel, genetically encoded optogenetic system for in planta applications.
• To overcome limitations of current optogenetic tools in plants, enabling high-resolution gene expression control.

Main Methods:

• Developed Highlighter, a synthetic, light-gated gene expression system based on the cyanobacterial CcaS-CcaR system.
• Repurposed and re-engineered the CcaS system for plant use, utilizing endogenous phytochromobilin and a novel blue light response.
• Deployed Highlighter in Nicotiana benthamiana for optogenetic control of fluorescent protein expression and downstream gene targets.

Main Results:

• Demonstrated successful green/red and blue light-dependent photoswitching of the re-engineered CcaS system.
• Achieved unprecedented spatiotemporal control of gene expression in neighboring plant cells using light.
• Showcased optogenetic modulation of plant immunity and pigment production by altering light spectral composition.

Conclusions:

• Highlighter provides a robust, genetically encoded optogenetic solution for plants.
• This system enables high-resolution gene induction, advancing fundamental plant science.
• Highlighter offers new avenues for crop improvement and biotechnological applications.