Homeostasis in C. elegans sleep is characterized by two behaviorally and genetically distinct mechanisms

  1. Stanislav Nagy
  2. Nora Tramm
  3. Jarred Sanders
  4. Shachar Iwanir
  5. Ian A Shirley
  6. Erel Levine
  7. David Biron  Is a corresponding author
  1. University of Chicago, United States
  2. Harvard University, United States

Abstract

Biological homeostasis invokes modulatory responses aimed at stabilizing internal conditions. Using tunable photo- and mechano-stimulation, we identified two distinct categories of homeostatic responses during the sleep-like state of C. elegans (lethargus). In the presence of weak or no stimuli, extended motion caused a subsequent extension of quiescence. The neuropeptide Y receptor homolog, NPR-1, and an inhibitory neuropeptide known to activate it, FLP-18, were required for this process. In the presence of strong stimuli, the correlations between motion and quiescence were disrupted for several minutes but homeostasis manifested as an overall elevation of the time spent in quiescence. This response to strong stimuli required the function of the DAF-16/FOXO transcription factor in neurons, but not that of NPR-1. Conversely, response to weak stimuli did not require the function of DAF-16/FOXO. These findings suggest that routine homeostatic stabilization of sleep may be distinct from homeostatic compensation following a strong disturbance.

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Author details

  1. Stanislav Nagy

    Institute for Biophysical Dynamics, University of Chicago, Chicago, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Nora Tramm

    Department of Physics, James Franck Institute, University of Chicago, Chicago, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Jarred Sanders

    Committee on Genetics, Genomics, and Systems Biology, University of Chicago, Chicago, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Shachar Iwanir

    Department of Physics, James Franck Institute, University of Chicago, Chicago, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Ian A Shirley

    Department of Physics, James Franck Institute, University of Chicago, Chicago, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Erel Levine

    Department of Physics, Harvard University, cambridge, United States
    Competing interests
    The authors declare that no competing interests exist.
  7. David Biron

    Institute for Biophysical Dynamics, University of Chicago, Chicago, United States
    For correspondence
    david.biron@gmail.com
    Competing interests
    The authors declare that no competing interests exist.

Copyright

© 2014, Nagy 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. Stanislav Nagy
  2. Nora Tramm
  3. Jarred Sanders
  4. Shachar Iwanir
  5. Ian A Shirley
  6. Erel Levine
  7. David Biron
(2014)
Homeostasis in C. elegans sleep is characterized by two behaviorally and genetically distinct mechanisms
eLife 3:e04380.
https://doi.org/10.7554/eLife.04380

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https://doi.org/10.7554/eLife.04380

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