Reference - Detail
|Author||Bhatla N, Horvitz HR.|
|Title||Light and hydrogen peroxide inhibit C. elegans Feeding through gustatory receptor orthologs and pharyngeal neurons.|
While gustatory sensing of the five primary flavors (sweet, salty, sour, bitter, and savory) has been extensively studied, pathways that detect non-canonical taste stimuli remain relatively unexplored. In particular, while reactive oxygen species cause generalized damage to biological systems, no gustatory mechanism to prevent ingestion of such material has been identified in any organism. We observed that light inhibits C. elegans feeding and used light as a tool to uncover molecular and neural mechanisms for gustation. Light can generate hydrogen peroxide, and we discovered that hydrogen peroxide similarly inhibits feeding. The gustatory receptor family members LITE-1 and GUR-3 are required for the inhibition of feeding by light and hydrogen peroxide. The I2 pharyngeal neurons increase calcium in response to light and hydrogen peroxide, and these responses require GUR-3 and a conserved antioxidant enzyme peroxiredoxin PRDX-2. Our results demonstrate a gustatory mechanism that mediates the detection and blocks ingestion of a non-canonical taste stimulus, hydrogen peroxide.
|MeSH||Animals Animals, Genetically Modified Caenorhabditis elegans Caenorhabditis elegans Proteins / genetics Caenorhabditis elegans Proteins / metabolism Calcium / metabolism Dose-Response Relationship, Radiation Drosophila Proteins / genetics Drosophila Proteins / metabolism* Feeding Behavior* / drug effects Feeding Behavior* / physiology Feeding Behavior* / radiation effects Hydrogen Peroxide / pharmacology* Laser Therapy Light* Locomotion / drug effects Locomotion / radiation effects Membrane Proteins / genetics Membrane Proteins / metabolism Mutation / genetics Neurons* / drug effects Neurons* / physiology Neurons* / radiation effects Optogenetics Oxidants / pharmacology* Peroxiredoxins / genetics Peroxiredoxins / metabolism Pharynx / cytology* Reaction Time / drug effects Receptors, Cell Surface / genetics Receptors, Cell Surface / metabolism*|