Closed-loop optogenetic activation of peripheral or central neurons modulates feeding in freely moving Drosophila

Abstract

Manipulating feeding circuits in freely moving animals is challenging, in part because the timing of sensory inputs is affected by the animal's behavior. To address this challenge in Drosophila, we developed the Sip-Triggered Optogenetic Behavior Enclosure ('STROBE'). The STROBE is a closed-looped system for real-time optogenetic activation of feeding flies, designed to evoke neural excitation coincident with food contact. We previously demonstrated the STROBE's utility in probing the valence of fly sensory neurons (Jaeger et al., 2018). Here we provide a thorough characterization of the STROBE system, demonstrate that STROBE-driven behavior is modified by hunger and the presence of taste ligands, and find that mushroom body dopaminergic input neurons and their respective post-synaptic partners drive opposing feeding behaviors following activation. Together, these results establish the STROBE as a new tool for dissecting fly feeding circuits and suggest a role for mushroom body circuits in processing naïve taste responses.

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Author details

  1. Pierre-Yves Musso

    Department of Zoology, Life Sciences Institute, University of British Columbia, Vancouver, Canada
    Competing interests
    The authors declare that no competing interests exist.
  2. Pierre Junca

    Department of Zoology, Life Sciences Institute, University of British Columbia, Vancouver, Canada
    Competing interests
    The authors declare that no competing interests exist.
  3. Meghan Jelen

    Department of Zoology, Life Sciences Institute, University of British Columbia, Vancouver, Canada
    Competing interests
    The authors declare that no competing interests exist.
  4. Damian Feldman-Kiss

    Department of Zoology, Life Sciences Institute, University of British Columbia, Vancouver, Canada
    Competing interests
    The authors declare that no competing interests exist.
  5. Han Zhang

    Engineering Physics Program, University of British Columbia, Vancouver, Canada
    Competing interests
    The authors declare that no competing interests exist.
  6. Rachel CW Chan

    Engineering Physics Program, University of British Columbia, Vancouver, Canada
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1009-6379
  7. Michael D Gordon

    Department of Zoology, Life Sciences Institute, University of British Columbia, Vancouver, Canada
    For correspondence
    gordon@zoology.ubc.ca
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5440-986X

Funding

Natural Sciences and Engineering Research Council of Canada (RGPIN-2016-03857)

  • Michael D Gordon

Natural Sciences and Engineering Research Council of Canada (RGPAS-49246-16)

  • Michael D Gordon

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Mani Ramaswami, Trinity College Dublin, Ireland

Publication history

  1. Received: January 31, 2019
  2. Accepted: July 18, 2019
  3. Accepted Manuscript published: July 19, 2019 (version 1)
  4. Version of Record published: July 31, 2019 (version 2)

Copyright

© 2019, Musso 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. Pierre-Yves Musso
  2. Pierre Junca
  3. Meghan Jelen
  4. Damian Feldman-Kiss
  5. Han Zhang
  6. Rachel CW Chan
  7. Michael D Gordon
(2019)
Closed-loop optogenetic activation of peripheral or central neurons modulates feeding in freely moving Drosophila
eLife 8:e45636.
https://doi.org/10.7554/eLife.45636
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