
Feeding status and serotonin rapidly and reversibly modulate a Caenorhabditis elegans chemosensory circuit
Author(s) -
Michael Y. Chao,
Hidetoshi Komatsu,
Hana S. Fukuto,
Heather Dionne,
Anne C. Hart
Publication year - 2004
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.0403369101
Subject(s) - caenorhabditis elegans , biology , neuroscience , glutamatergic , sensory system , serotonin , stimulus (psychology) , glutamate receptor , sensory neuron , signal transduction , microbiology and biotechnology , receptor , biochemistry , psychology , gene , psychotherapist
Serotonin (5-HT) modulates synaptic efficacy in the nervous system of vertebrates and invertebrates. In the nematode Caenorhabditis elegans, many behaviors are regulated by 5-HT levels, which are in turn regulated by the presence or absence of food. Here, we show that both food and 5-HT signaling modulate chemosensory avoidance response of octanol in C. elegans, and that this modulation is both rapid and reversible. Sensitivity to octanol is decreased when animals are off food or when 5-HT levels are decreased; conversely, sensitivity is increased when animals are on food or have increased 5-HT signaling. Laser microsurgery and behavioral experiments reveal that sensory input from different subsets of octanol-sensing neurons is selectively used, depending on stimulus strength, feeding status, and 5-HT levels. 5-HT directly targets at least one pair of sensory neurons, and 5-HT signaling requires the Galpha protein GPA-11. Glutamatergic signaling is required for response to octanol, and the GLR-1 glutamate receptor plays an important role in behavioral response off food but not on food. Our results demonstrate that 5-HT modulation of neuronal activity via G protein signaling underlies behavioral plasticity by rapidly altering the functional circuitry of a chemosensory circuit.