title: Organization of Circadian Behavior Relies on Glycinergic Transmission.
abstract: The small ventral lateral neurons (sLNvs) constitute a central circadian pacemaker in the Drosophila brain. They organize daily locomotor activity, partly through the release of the neuropeptide pigment-dispersing factor (PDF), coordinating the action of the remaining clusters required for network synchronization. Despite extensive efforts, the basic principles underlying communication among circadian clusters remain obscure. We identified classical neurotransmitters released by sLNvs through disruption of specific transporters. Adult-specific RNAi-mediated downregulation of the glycine transporter or impairment of glycine synthesis in LNv neurons increased period length by nearly an hour without affecting rhythmicity of locomotor activity. Electrophysiological recordings showed that glycine reduces spiking frequency in circadian neurons. Interestingly, downregulation of glycine receptor subunits in specific sLNv targets impaired rhythmicity, revealing involvement of glycine in information processing within the network. These data identify glycinergic inhibition of specific targets as a cue that contributes to the synchronization of the circadian network.
authors.affiliation: Laboratorio de Genética del Comportamiento, Fundación Instituto Leloir (FIL) IIBBA-CONICET, 1405BWE Buenos Aires, Argentina.
authors.forename: Lia
authors.initials: L
authors.lastname: Frenkel
authors.affiliation: Laboratorio de Genética del Comportamiento, Fundación Instituto Leloir (FIL) IIBBA-CONICET, 1405BWE Buenos Aires, Argentina.
authors.forename: Nara I
authors.initials: NI
authors.lastname: Muraro
authors.affiliation: Laboratorio de Neurobiología Celular y Molecular, INGEBI-CONICET, C1428ADN Buenos Aires, Argentina.
authors.forename: Andrea N
authors.initials: AN
authors.lastname: Beltrán González
authors.affiliation: Laboratorio de Amiloidosis y Neurodegeneración, FIL-IIBBA-CONICET, 1405BWE Buenos Aires, Argentina.
authors.forename: María S
authors.initials: MS
authors.lastname: Marcora
authors.affiliation: Laboratorio de Genética del Comportamiento, Fundación Instituto Leloir (FIL) IIBBA-CONICET, 1405BWE Buenos Aires, Argentina.
authors.forename: Guillermo
authors.initials: G
authors.lastname: Bernabó
authors.affiliation: Department of Neurobiology and Genetics, Theodor-Boveri Institute, Biocenter, University of Wuerzburg, Wuerzburg 97070, Germany.
authors.forename: Christiane
authors.initials: C
authors.lastname: Hermann-Luibl
authors.affiliation: Laboratorio de Genética del Comportamiento, Fundación Instituto Leloir (FIL) IIBBA-CONICET, 1405BWE Buenos Aires, Argentina.
authors.forename: Juan I
authors.initials: JI
authors.lastname: Romero
authors.affiliation: Department of Neurobiology and Genetics, Theodor-Boveri Institute, Biocenter, University of Wuerzburg, Wuerzburg 97070, Germany.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Helfrich-Förster
authors.affiliation: Laboratorio de Amiloidosis y Neurodegeneración, FIL-IIBBA-CONICET, 1405BWE Buenos Aires, Argentina.
authors.forename: Eduardo M
authors.initials: EM
authors.lastname: Castaño
authors.affiliation: Laboratorio de Bioinformática Estructural, FIL-IIBBA-CONICET, 1405BWE Buenos Aires, Argentina.
authors.forename: Cristina
authors.initials: C
authors.lastname: Marino-Busjle
authors.affiliation: Laboratorio de Neurobiología Celular y Molecular, INGEBI-CONICET, C1428ADN Buenos Aires, Argentina.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Calvo
authors.affiliation: Laboratorio de Genética del Comportamiento, Fundación Instituto Leloir (FIL) IIBBA-CONICET, 1405BWE Buenos Aires, Argentina. Electronic address: fceriani@leloir.org.ar.
authors.forename: M Fernanda
authors.initials: MF
authors.lastname: Ceriani
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D001921:Brain / Q000378:metabolism; D002940:Circadian Rhythm / Q000502:physiology*; D015536:Down-Regulation; D029721:Drosophila Proteins / Q000378:metabolism; D004331:Drosophila melanogaster / Q000378:metabolism; D005998:Glycine / Q000378:metabolism*; D050487:Glycine Plasma Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D009474:Neurons / Q000378:metabolism; D009479:Neuropeptides / Q000378:metabolism; D018377:Neurotransmitter Agents / Q000378:metabolism; D034622:RNA Interference; D018009:Receptors, Glycine / Q000235:genetics / Q000378:metabolism*; D009435:Synaptic Transmission
chemical_list: D029721:Drosophila Proteins; D050487:Glycine Plasma Membrane Transport Proteins; D009479:Neuropeptides; D018377:Neurotransmitter Agents; D018009:Receptors, Glycine; C113883:pdf protein, Drosophila; D005998:Glycine
keywords: Drosophila; circadian rhythms; glycine; glycine receptor subunit; glycine transporter; inhibitory neurotransmission; sleep-wake cycles