Taste sensing and sugar detection mechanisms in Drosophila larval primary taste center

  1. G Larisa Maier
  2. Nikita Komarov
  3. Felix Meyenhofer
  4. Jae Young Kwon
  5. Simon G Sprecher  Is a corresponding author
  1. University of Fribourg, Switzerland
  2. Sungkyunkwan University, Republic of Korea

Abstract

Despite the small number of gustatory sense neurons, Drosophila larvae are able to sense a wide range of chemicals. Although evidence for taste multimodality has been provided in single neurons, an overview of gustatory responses at the periphery is missing and hereby we explore whole-organ calcium imaging of the external taste center. We find that neurons can be activated by different combinations of taste modalities including of opposite hedonic valence and identify distinct temporal dynamics of response. Although sweet sensing has not been fully characterized so far in the external larval gustatory organ, we recorded responses elicited by sugar. Previous findings established that larval sugar sensing relies on the Gr43a pharyngeal receptor, but the question remains if external neurons contribute to this taste. Here we postulate that external and internal gustation use distinct and complementary mechanisms in sugar sensing and we identify external sucrose sensing neurons.

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All data is available as part of the submitted manuscript.

Article and author information

Author details

  1. G Larisa Maier

    Department of Biology, University of Fribourg, Fribourg, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  2. Nikita Komarov

    Department of Biology, University of Fribourg, Fribourg, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  3. Felix Meyenhofer

    Department of Biology, University of Fribourg, Fribourg, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  4. Jae Young Kwon

    Department of Biological Sciences, Sungkyunkwan University, Suwon, Republic of Korea
    Competing interests
    The authors declare that no competing interests exist.
  5. Simon G Sprecher

    Department of Biology, University of Fribourg, Fribourg, Switzerland
    For correspondence
    simon.sprecher@unifr.ch
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9060-3750

Funding

Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung (310030_188471)

  • Simon G Sprecher

Novartis Stiftung für Medizinisch-Biologische Forschung (18A017)

  • Simon G Sprecher

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

Reviewing Editor

  1. Sonia Sen, Tata Institute for Genetics and Society, India

Publication history

  1. Received: February 24, 2021
  2. Accepted: November 23, 2021
  3. Accepted Manuscript published: December 3, 2021 (version 1)
  4. Version of Record published: December 24, 2021 (version 2)

Copyright

© 2021, Maier 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. G Larisa Maier
  2. Nikita Komarov
  3. Felix Meyenhofer
  4. Jae Young Kwon
  5. Simon G Sprecher
(2021)
Taste sensing and sugar detection mechanisms in Drosophila larval primary taste center
eLife 10:e67844.
https://doi.org/10.7554/eLife.67844

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