Drosophila gustatory projections are segregated by taste modality and connectivity

  1. Stefanie Engert
  2. Gabriella R Sterne
  3. Davi D Bock
  4. Kristin Scott  Is a corresponding author
  1. University of California, Berkeley, United States
  2. University of California Berkeley, United States
  3. University of Vermont, United States

Abstract

Gustatory sensory neurons detect caloric and harmful compounds in potential food and convey this information to the brain to inform feeding decisions. To examine the signals that gustatory neurons transmit and receive, we reconstructed gustatory axons and their synaptic sites in the adult Drosophila melanogaster brain, utilizing a whole-brain electron microscopy volume. We reconstructed 87 gustatory projections from the proboscis labellum in the right hemisphere and 57 from the left, representing the majority of labellar gustatory axons. Gustatory neurons contain a nearly equal number of interspersed pre-and post-synaptic sites, with extensive synaptic connectivity among gustatory axons. Morphology- and connectivity-based clustering revealed six distinct groups, likely representing neurons recognizing different taste modalities. The vast majority of synaptic connections are between neurons of the same group. This study resolves the anatomy of labellar gustatory projections, reveals that gustatory projections are segregated based on taste modality, and uncovers synaptic connections that may alter the transmission of gustatory signals.

Data availability

FAFB neuronal reconstructions will be available from Virtual Fly Brain (https://fafb.catmaid.virtualflybrain.org/).

Article and author information

Author details

  1. Stefanie Engert

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0644-8116
  2. Gabriella R Sterne

    Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7221-648X
  3. Davi D Bock

    Department of Neurological Sciences, University of Vermont, Burlington, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8218-7926
  4. Kristin Scott

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    For correspondence
    kscott@berkeley.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3150-7210

Funding

National Institutes of Health (R01DC013280)

  • Kristin Scott

National Institutes of Health (F32DK117671)

  • Gabriella R Sterne

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

Reviewing Editor

  1. Marta Zlatic, MRC Laboratory of Molecular Biology, United Kingdom

Publication history

  1. Preprint posted: December 9, 2021 (view preprint)
  2. Received: February 23, 2022
  3. Accepted: May 24, 2022
  4. Accepted Manuscript published: May 25, 2022 (version 1)
  5. Version of Record published: June 6, 2022 (version 2)

Copyright

© 2022, Engert 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. Stefanie Engert
  2. Gabriella R Sterne
  3. Davi D Bock
  4. Kristin Scott
(2022)
Drosophila gustatory projections are segregated by taste modality and connectivity
eLife 11:e78110.
https://doi.org/10.7554/eLife.78110

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