A single pair of neurons links sleep to memory consolidation in Drosophila melanogaster

  1. Paula R Haynes
  2. Bethany L Christmann
  3. Leslie C Griffith  Is a corresponding author
  1. Brandeis University, United States

Abstract

Sleep promotes memory consolidation in humans and many other species, but the physiological and anatomical relationships between sleep and memory remain unclear. Here we show the dorsal paired medial (DPM) neurons, which are required for memory consolidation in Drosophila, are sleep-promoting inhibitory neurons. DPMs increase sleep via release of GABA onto wake-promoting mushroom body (MB) α'/β' neurons. Functional imaging demonstrates that DPM activation evokes robust increases in chloride in MB neurons, but is unable to cause detectable increases in calcium or cAMP. Downregulation of α'/β' GABAA and GABABR3 receptors results in sleep loss, suggesting these receptors are the sleep-relevant targets of DPM-mediated inhibition. Regulation of sleep by neurons necessary for consolidation suggests that these brain processes may be functionally interrelated via their shared anatomy. These findings have important implications for the mechanistic relationship between sleep and memory consolidation, arguing for a significant role of inhibitory neurotransmission in regulating these processes.These results argue for a significant role of inhibitory neurotransmission in memory consolidation and its regulation by sleep.

Article and author information

Author details

  1. Paula R Haynes

    Department of Biology, Volen Center for Complex Systems, National Center for Behavioral Genomics, Brandeis University, Waltham, United States
    Competing interests
    No competing interests declared.
  2. Bethany L Christmann

    Department of Biology, Volen Center for Complex Systems, National Center for Behavioral Genomics, Brandeis University, Waltham, United States
    Competing interests
    No competing interests declared.
  3. Leslie C Griffith

    Department of Biology, Volen Center for Complex Systems, National Center for Behavioral Genomics, Brandeis University, Waltham, United States
    For correspondence
    griffith@brandeis.edu
    Competing interests
    Leslie C Griffith, Reviewing editor, eLife.

Reviewing Editor

  1. Graeme W Davis, University of California, San Francisco, United States

Version history

  1. Received: July 3, 2014
  2. Accepted: January 7, 2015
  3. Accepted Manuscript published: January 7, 2015 (version 1)
  4. Version of Record published: January 26, 2015 (version 2)

Copyright

© 2015, Haynes 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. Paula R Haynes
  2. Bethany L Christmann
  3. Leslie C Griffith
(2015)
A single pair of neurons links sleep to memory consolidation in Drosophila melanogaster
eLife 4:e03868.
https://doi.org/10.7554/eLife.03868

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https://doi.org/10.7554/eLife.03868

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