Highly efficient optogenetic cell ablation in C. elegans using membrane-targeted miniSOG.

Area of Science:

• Genetics
• Molecular Biology
• Neuroscience

Background:

• The genetically encoded photosensitizer mini Singlet Oxygen Generator (miniSOG) induces cell death via reactive oxygen species (ROS) generation upon blue light illumination.
• Targeting miniSOG to specific cellular compartments, like mitochondria (mito-miniSOG), has been used for optogenetic cell ablation in C. elegans neurons.

Purpose of the Study:

• To enhance the efficiency and expand the applicability of miniSOG-based optogenetic cell ablation in C. elegans.
• To investigate alternative targeting strategies for miniSOG to improve cell killing efficacy across different cell types.

Main Methods:

• Engineered miniSOG variants with alternative subcellular targeting signals, particularly membrane localization.
• Introduced a point mutation to increase miniSOG's ROS generation capacity.
• Applied blue light illumination to induce optogenetic cell ablation in neurons and non-neuronal tissues.

Main Results:

• Membrane-targeted miniSOG demonstrated highly efficient cell killing compared to mitochondrial targeting.
• Combining membrane targeting with increased ROS generation significantly reduced ablation time (by over tenfold for neurons).
• The technique was successfully extended to ablate non-neuronal tissues, revealing the epidermis's role in locomotion.

Conclusions:

• Membrane targeting is a key strategy for enhancing miniSOG-based optogenetic cell ablation efficiency.
• Improved miniSOG variants offer a faster and more versatile tool for genetic ablation studies in C. elegans.
• This technique facilitates high-throughput functional studies by enabling rapid ablation in diverse tissues.