Circadian programming of the ellipsoid body sleep homeostat in Drosophila

  1. Tomas Andreani
  2. Clark Rosensweig
  3. Shiju Sisobhan
  4. Emmanuel Ogunlana
  5. William Kath
  6. Ravi Allada  Is a corresponding author
  1. 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

The following data sets were generated

Article and author information

Author details

  1. Tomas Andreani

    Department of Neurobiology, Northwestern University, Evanston, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2967-9689
  2. Clark Rosensweig

    Department of Neurobiology, Northwestern University, Evanston, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Shiju Sisobhan

    Department of Neurobiology, Northwestern University, Evanston, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9715-1029
  4. Emmanuel Ogunlana

    Department of Neurobiology, Northwestern University, Evanston, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7955-4115
  5. William Kath

    Department of Engineering Sciences and Applied Mathematics, Northwestern University, Evanston, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Ravi Allada

    Department of Neurobiology, Northwestern University, Chicago, United States
    For correspondence
    r-allada@northwestern.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4371-1577

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.

Reviewing Editor

  1. Amita Sehgal, Howard Hughes Medical Institute and Chronobiology and Sleep Institute, Perelman School of Medicine, University of Pennsylvania, United States

Publication history

  1. Received: September 29, 2021
  2. Accepted: June 23, 2022
  3. Accepted Manuscript published: June 23, 2022 (version 1)

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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  1. Tomas Andreani
  2. Clark Rosensweig
  3. Shiju Sisobhan
  4. Emmanuel Ogunlana
  5. William Kath
  6. Ravi Allada
(2022)
Circadian programming of the ellipsoid body sleep homeostat in Drosophila
eLife 11:e74327.
https://doi.org/10.7554/eLife.74327

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