CreLite: An optogenetically controlled Cre/loxP system using red light

Area of Science:

• Developmental Biology
• Genetics
• Optogenetics

Background:

• Precise control of gene expression is crucial for understanding biological systems.
• The Cre-loxP system is widely used but relies on specific regulatory elements for control.
• Existing methods lack sufficient temporal and spatial specificity in certain applications.

Purpose of the Study:

• To develop a novel optogenetically controlled Cre recombinase system.
• To achieve precise temporal and spatial control of gene expression using red light.
• To validate the CreLite system in developing zebrafish embryos.

Main Methods:

• Engineered Cre recombinase by splitting it into two inactive components fused with red light-inducible proteins (PhyB and PIF6).
• Utilized the cofactor phycocyanobilin (PCB) to reconstitute Cre activity upon red light exposure.
• Injected CreLite mRNAs and PCB into zebrafish embryos carrying a Cre-dependent reporter system.

Main Results:

• Demonstrated successful Cre activity restoration and gene manipulation in zebrafish embryos upon red light illumination.
• Achieved multispectral cell labeling in various tissues, indicating successful spatiotemporal control.
• Showcased the ability to target gene manipulation to whole embryos or specific cell groups.

Conclusions:

• CreLite provides a powerful tool for temporal and spatial gene manipulation in zebrafish.
• The system allows for precise control of gene expression at different developmental stages.
• CreLite holds potential for applications in cell culture, organ culture, and other animal models.