title: Analysis of NPR-1 reveals a circuit mechanism for behavioral quiescence in C. elegans.
abstract: Animals undergo periods of behavioral quiescence and arousal in response to environmental, circadian, or developmental cues. During larval molts, C. elegans undergoes a period of profound behavioral quiescence termed lethargus. Locomotion quiescence during lethargus was abolished in mutants lacking a neuropeptide receptor (NPR-1) and was reduced in mutants lacking NPR-1 ligands (FLP-18 and FLP-21). Wild-type strains are polymorphic for the npr-1 gene, and their lethargus behavior varies correspondingly. Locomotion quiescence and arousal were mediated by decreased and increased secretion of an arousal neuropeptide (PDF-1) from central neurons. PDF receptors (PDFR-1) expressed in peripheral mechanosensory neurons enhanced touch-evoked calcium transients. Thus, a central circuit stimulates arousal from lethargus by enhancing the sensitivity of peripheral mechanosensory neurons in the body. These results define a circuit mechanism controlling a developmentally programmed form of quiescence.
authors.affiliation: Department of Molecular Biology, Massachusetts General Hospital, Boston, MA 02114, USA.
authors.forename: Seungwon
authors.initials: S
authors.lastname: Choi
authors.forename: Marios
authors.initials: M
authors.lastname: Chatzigeorgiou
authors.forename: Kelsey P
authors.initials: KP
authors.lastname: Taylor
authors.forename: William R
authors.initials: WR
authors.lastname: Schafer
authors.forename: Joshua M
authors.initials: JM
authors.lastname: Kaplan
mesh_terms: D000367:Age Factors; D000818:Animals; D030801:Animals, Genetically Modified; D001143:Arousal / Q000235:genetics*; D001522:Behavior, Animal / Q000187:drug effects / Q000502:physiology*; D017173:Caenorhabditis elegans; D029742:Caenorhabditis elegans Proteins / Q000235:genetics / Q000378:metabolism*; D002211:Capsaicin / Q000494:pharmacology; D002490:Central Nervous System / Q000166:cytology; D007814:Larva; D053609:Lethargy / Q000235:genetics*; D008124:Locomotion / Q000187:drug effects / Q000235:genetics*; D009132:Muscles / Q000378:metabolism; D009154:Mutation / Q000235:genetics; D017476:Receptors, Neuropeptide Y / Q000235:genetics / Q000378:metabolism*; D011984:Sensory Receptor Cells / Q000187:drug effects / Q000502:physiology; D050916:TRPV Cation Channels; D014110:Touch / Q000235:genetics; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
chemical_list: D029742:Caenorhabditis elegans Proteins; C468272:NPR-1 protein, C elegans; D017476:Receptors, Neuropeptide Y; D050916:TRPV Cation Channels; C493922:Trpv1 protein, rat; D005680:gamma-Aminobutyric Acid; D002211:Capsaicin