AANAT1 functions in astrocytes to regulate sleep homeostasis
Abstract
How the brain controls the need and acquisition of recovery sleep after prolonged wakefulness is an important issue in sleep research. The monoamines serotonin and dopamine are key regulators of sleep in mammals and in Drosophila. We found that the enzyme arylalkylamine N-acetyltransferase 1 (AANAT1) is expressed by Drosophila astrocytes and specific subsets of neurons in the adult brain. AANAT1 acetylates monoamines and inactivates them, and we found that AANAT1 limited the accumulation of serotonin and dopamine in the brain upon sleep deprivation. Loss of AANAT1 from astrocytes, but not from neurons, caused flies to increase their daytime recovery sleep following overnight sleep deprivation. Together, these findings demonstrate a crucial role for AANAT1 and astrocytes in the regulation of monoamine bioavailability and homeostatic sleep.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
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Author details
Funding
Natural Sciences and Engineering Research Council of Canada (RGPIN-2017-05142)
- Donald J van Meyel
Canadian Institutes of Health Research (MOP-137034)
- Donald J van Meyel
National Institutes of Health (DK120757)
- Amita Sehgal
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- K VijayRaghavan, National Centre for Biological Sciences, Tata Institute of Fundamental Research, India
Version history
- Received: November 27, 2019
- Accepted: September 18, 2020
- Accepted Manuscript published: September 21, 2020 (version 1)
- Version of Record published: October 12, 2020 (version 2)
Copyright
© 2020, Davla 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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