The ion channel narrow abdomen is critical for neural output of the Drosophila circadian pacemaker.
Circadian clocks consist of transcriptional feedback loops housed in interdependent pacemaker neurons. Yet little is known about the neuronal output components essential for rhythmic behavior. Drosophila mutants of a putative ion channel, narrow abdomen (na), exhibit poor circadian rhythms and suppressed daylight activity. We find that NA is expressed in pacemaker neurons and induced expression within circadian neurons is sufficient to rescue these mutant phenotypes. Selective na rescue in distinct pacemaker neurons influences rhythmicity and timing of behavior. Oscillations of the clock protein PERIOD are intact in na mutants, indicating an output role. Pore residues are required for robust rescue consistent with NA action as an ion channel. In na mutants, expression of potassium currents and the key neuropeptide PDF are elevated, the latter consistent with reduced release. These data implicate NA and the pacemaker neural network in controlling phase and rhythmicity.
Lear
Bridget C
BC
Department of Neurobiology and Physiology, Northwestern University, Evanston, Illinois 60208, USA.
Lin
Jui-Ming
JM
Keath
J Russel
JR
McGill
Jermaine J
JJ
Raman
Indira M
IM
Allada
Ravi
R
D000818:Animals; D001683:Biological Clocks / Q000235:genetics*; D001921:Brain / Q000166:cytology / Q000378:metabolism*; D002940:Circadian Rhythm / Q000235:genetics*; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000166:cytology / Q000235:genetics / Q000378:metabolism*; D005260:Female; D007473:Ion Channels / Q000235:genetics / Q000378:metabolism*; D008297:Male; D009154:Mutation / Q000235:genetics; D009415:Nerve Net / Q000166:cytology / Q000378:metabolism; D009434:Neural Pathways / Q000166:cytology / Q000378:metabolism; D009474:Neurons / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D009479:Neuropeptides / Q000235:genetics / Q000378:metabolism; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism; D056950:Period Circadian Proteins; D015221:Potassium Channels / Q000235:genetics / Q000378:metabolism; D015222:Sodium Channels / Q000235:genetics / Q000378:metabolism; D009435:Synaptic Transmission / Q000235:genetics
D029721:Drosophila Proteins; D007473:Ion Channels; C476573:Na protein, Drosophila; D009479:Neuropeptides; D009687:Nuclear Proteins; C539040:PER protein, Drosophila; D056950:Period Circadian Proteins; D015221:Potassium Channels; D015222:Sodium Channels; C113883:pdf protein, Drosophila