Memory of recent oxygen experience switches pheromone valence in <i>Caenorhabditis elegans</i>.

Fenk, Lorenz A; de Bono, Mario · Proc Natl Acad Sci U S A · 2017

basic_science · Level V

Where this comes from

Abstract

Animals adjust their behavioral priorities according to momentary needs and prior experience. We show that <i>Caenorhabditis elegans</i> changes how it processes sensory information according to the oxygen environment it experienced recently. <i>C. elegans</i> acclimated to 7% O<sub>2</sub> are aroused by CO<sub>2</sub> and repelled by pheromones that attract animals acclimated to 21% O<sub>2</sub> This behavioral plasticity arises from prolonged activity differences in a circuit that continuously signals O<sub>2</sub> levels. A sustained change in the activity of O<sub>2</sub>-sensing neurons reprograms the properties of their postsynaptic partners, the RMG hub interneurons. RMG is gap-junctionally coupled to the ASK and ADL pheromone sensors that respectively drive pheromone attraction and repulsion. Prior O<sub>2</sub> experience has opposite effects on the pheromone responsiveness of these neurons. These circuit changes provide a physiological correlate of altered pheromone valence. Our results suggest <i>C. elegans</i> stores a memory of recent O<sub>2</sub> experience in the RMG circuit and illustrate how a circuit is flexibly sculpted to guide behavioral decisions in a context-dependent manner.

Medical subject headings