Acute control of the sleep switch in Drosophila reveals a role for gap junctions in regulating behavioral responsiveness
- The University of Queensland, Australia
- Washington University in St. Louis, United States
Abstract
Sleep is a dynamic process in most animals, involving distinct stages that probably achieve multiple functions for the brain. Before sleep functions can be initiated, it is likely that behavioral responsiveness to the outside world needs to be reduced first, even while animals are still awake. Recent work in Drosophila has uncovered a sleep switch in the dorsal fan-shaped body (dFB) of the fly's central brain, but it is unknown if these sleep-promoting neurons also govern the acute need to ignore salient stimuli in the environment during sleep transitions. We found that optogenetic activation of the sleep switch suppressed behavioral responsiveness to mechanical stimuli, even in awake flies, indicating a broader role for these neurons in regulating arousal. The dFB-mediated suppression mechanism and its associated neural correlates requires innexin6 expression, suggesting that the acute need to reduce sensory perception when flies fall asleep is mediated in part by electrical synapses.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
Article and author information
Author details
Martyna J Grabowska
Bruno van Swinderen
Funding
National Institutes of Health (R01 NS076980)
- Melvyn HW Yap
- Paul Shaw
- Bruno van Swinderen
National Health and Medical Research Council (GNT1065713)
- Michael Troup
- Chelsie Rohrscheib
- Aoife Larkin
- Bruno van Swinderen
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Troup et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Acute control of the sleep switch in Drosophila reveals a role for gap junctions in regulating behavioral responsiveness
eLife 7:e37105.
https://doi.org/10.7554/eLife.37105
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