Circadian programming of the ellipsoid body sleep homeostat in Drosophila
- Northwestern University, United States
Abstract
Homeostatic and circadian processes collaborate to appropriately time and consolidate sleep and wake. To understand how these processes are integrated, we scheduled brief sleep deprivation at different times of day in Drosophila and find elevated morning rebound compared to evening. These effects depend on discrete morning and evening clock neurons, independent of their roles in circadian locomotor activity. In the R5 ellipsoid body sleep homeostat, we identified elevated morning expression of activity dependent and presynaptic gene expression as well as the presynaptic protein BRUCHPILOT consistent with regulation by clock circuits. These neurons also display elevated calcium levels in response to sleep loss in the morning, but not the evening consistent with the observed time-dependent sleep rebound. These studies reveal the circuit and molecular mechanisms by which discrete circadian clock neurons program a homeostatic sleep center.
Data availability
Sequencing data have been deposited in GEO under accession code GSE186076
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Next generation sequencing of isolated R5 ellipsoid body neurons of Drosophila in the morning and evening with and without sleep deprivationNCBI Gene Expression Omnibus GSE186076.
Article and author information
Author details
Funding
National Institutes of Health (R01NS106955)
- Ravi Allada
Army Research Office (W911NF1610584)
- Ravi Allada
National Science Foundation (DMS-1764421)
- William Kath
- Ravi Allada
Simons Foundation (597491-RWC)
- William Kath
- Ravi Allada
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2022, Andreani 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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Circadian programming of the ellipsoid body sleep homeostat in Drosophila
eLife 11:e74327.
https://doi.org/10.7554/eLife.74327
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