Photo-inducible cell ablation in Caenorhabditis elegans using the genetically encoded singlet oxygen generating protein miniSOG

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 109; no. 19; pp. 7499 - 7504
• Main Authors: Qi, Yingchuan B, Garren, Emma J, Shu, Xiaokun, Tsien, Roger Y, Jin, Yishi
• Format: Journal Article
• Language: English
• Published: United States National Academy of Sciences 08.05.2012; National Acad Sciences
• Subjects: acetylcholine; Acetylcholine receptors; Amino acids; Animals; Animals, Genetically Modified; Biological Sciences; blue light; Caenorhabditis elegans; Caenorhabditis elegans - cytology; Caenorhabditis elegans - genetics; Caenorhabditis elegans - metabolism; Caenorhabditis elegans Proteins - genetics; Caenorhabditis elegans Proteins - metabolism; Caspase; caspases; Caspases - genetics; Caspases - metabolism; Cell Death - radiation effects; Cell Survival - radiation effects; Cells; Convulsions; death; Developmental stages; Dose-Response Relationship, Radiation; Flavoproteins - genetics; Flavoproteins - metabolism; Fluorescence; Genetic code; humans; Illumination; Interneurons; Interneurons - cytology; Interneurons - metabolism; Interneurons - radiation effects; Larvae; Light; lighting; Locomotion; Luminescent Proteins - genetics; Luminescent Proteins - metabolism; Medical genetics; Membrane Proteins - genetics; Membrane Proteins - metabolism; Microscopy, Confocal; Microscopy, Fluorescence; Mitochondria; Mitochondria - metabolism; Motor neurons; Motor Neurons - cytology; Motor Neurons - metabolism; Motor Neurons - radiation effects; Mutation; Nematodes; Neurons; Neurons - cytology; Neurons - metabolism; Neurons - radiation effects; Oxygen; Phagocytes; Proteins; Receptors, Nicotinic - genetics; Receptors, Nicotinic - metabolism; singlet oxygen; Singlet Oxygen - metabolism; Time Factors; Transgenic animals
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.1204096109

We describe a method for light-inducible and tissue-selective cell ablation using a genetically encoded photosensitizer, miniSOG (mini singlet oxygen generator). miniSOG is a newly engineered fluorescent protein of 106 amino acids that generates singlet oxygen in quantum yield upon blue-light illumination. We transgenically expressed mitochondrially targeted miniSOG (mito-miniSOG) in Caenorhabditis elegans neurons. Upon blue-light illumination, mito-miniSOG causes rapid and effective death of neurons in a cell-autonomous manner without detectable damages to surrounding tissues. Neuronal death induced by mito-miniSOG appears to be independent of the caspase CED-3, but the clearance of the damaged cells partially depends on the phagocytic receptor CED-1, a homolog of human CD91. We show that neurons can be killed at different developmental stages. We further use this method to investigate the role of the premotor interneurons in regulating the convulsive behavior caused by a gain-of-function mutation in the neuronal acetylcholine receptor acr-2. Our findings support an instructive role for the interneuron AVB in controlling motor neuron activity and reveal an inhibitory effect of the backward premotor interneurons on the forward interneurons. In summary, the simple inducible cell ablation method reported here allows temporal and spatial control and will prove to be a useful tool in studying the function of specific cells within complex cellular contexts.