1. Neuroscience
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Long-range projection neurons in the taste circuit of Drosophila

  1. Heesoo Kim  Is a corresponding author
  2. Colleen Kirkhart
  3. Kristin Scott  Is a corresponding author
  1. University of California, Berkeley, United States
  2. University of California, Berkeley, Berkeley, United States
Research Article
  • Cited 23
  • Views 3,687
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Cite this article as: eLife 2017;6:e23386 doi: 10.7554/eLife.23386

Abstract

Taste compounds elicit innate feeding behaviors and act as rewards or punishments to entrain other cues. The neural pathways by which taste compounds influence innate and learned behaviors have not been resolved. Here, we identify three classes of taste projection neurons (TPNs) in Drosophila melanogaster distinguished by their morphology and taste selectivity. TPNs receive input from gustatory receptor neurons and respond selectively to sweet or bitter stimuli, demonstrating segregated processing of different taste modalities. Activation of TPNs influences innate feeding behavior, whereas inhibition has little effect, suggesting parallel pathways. Moreover, two TPN classes are absolutely required for conditioned taste aversion, a learned behavior. The TPNs essential for conditioned aversion project to the superior lateral protocerebrum (SLP) and convey taste information to mushroom body learning centers. These studies identify taste pathways from sensory detection to higher brain that influence innate behavior and are essential for learned responses to taste compounds.

Article and author information

Author details

  1. Heesoo Kim

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    For correspondence
    heesoo@berkeley.edu
    Competing interests
    No competing interests declared.
  2. Colleen Kirkhart

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    No competing interests declared.
  3. Kristin Scott

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, Berkeley, United States
    For correspondence
    kscott@berkeley.edu
    Competing interests
    Kristin Scott, Reviewing editor, eLife.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3150-7210

Funding

National Institute of Dental and Craniofacial Research (DC013280)

  • Kristin Scott

National Science Foundation

  • Colleen Kirkhart

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

Reviewing Editor

  1. Hugo J Bellen, Baylor College of Medicine, United States

Publication history

  1. Received: November 16, 2016
  2. Accepted: February 6, 2017
  3. Accepted Manuscript published: February 6, 2017 (version 1)
  4. Version of Record published: February 15, 2017 (version 2)

Copyright

© 2017, Kim 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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