Ionotropic Receptor-dependent moist and dry cells control hygrosensation in Drosophila

  1. Zachary A Knecht
  2. Ana F Silbering
  3. Joyner Cruz
  4. Ludi Yang
  5. Vincent Croset
  6. Richard Benton  Is a corresponding author
  7. Paul A Garrity  Is a corresponding author
  1. Brandeis University, United States
  2. University of Lausanne, Switzerland
  3. University of Oxford, United Kingdom

Abstract

Insects use hygrosensation (humidity sensing) to avoid desiccation and, in vectors such as mosquitoes, to locate vertebrate hosts. Sensory neurons activated by either dry or moist air ('dry cells' and 'moist cells') have been described in many insects, but their behavioral roles and the molecular basis of their hygrosensitivity remain unclear. We recently reported that Drosophila hygrosensation relies on three Ionotropic Receptors (IRs) required for dry cell function: IR25a, IR93a and IR40a (Knecht et al., 2016). Here we discover Drosophila moist cells, and show they require IR25a and IR93a together with IR68a, a conserved, but orphan IR. Both IR68a- and IR40a-dependent pathways drive hygrosensory behavior: each is important for dry-seeking by hydrated flies and together they underlie moist-seeking by dehydrated flies. These studies reveal that humidity sensing in Drosophila, and likely other insects, involves the combined activity of two molecularly related but neuronally distinct hygrosensing systems.

Article and author information

Author details

  1. Zachary A Knecht

    National Center for Behavioral Genomics, Brandeis University, Waltham, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Ana F Silbering

    Center for Integrative Genomics, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  3. Joyner Cruz

    National Center for Behavioral Genomics, Brandeis University, Waltham, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Ludi Yang

    National Center for Behavioral Genomics, Brandeis University, Waltham, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Vincent Croset

    Centre for Neural Circuits and Behaviour, University of Oxford, Oxford, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  6. Richard Benton

    Center for Integrative Genomics, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
    For correspondence
    Richard.Benton@unil.ch
    Competing interests
    The authors declare that no competing interests exist.
  7. Paul A Garrity

    National Center for Behavioral Genomics, Brandeis University, Waltham, United States
    For correspondence
    pgarrity@brandeis.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8274-6564

Funding

National Institute on Deafness and Other Communication Disorders (F31 DC015155)

  • Zachary A Knecht

Boehringer Ingelheim Stiftung

  • Vincent Croset

H2020 European Research Council (205202)

  • Richard Benton

H2020 European Research Council (615094)

  • Richard Benton

Swiss National Science Foundation (31003A_140869)

  • Richard Benton

National Institute of General Medical Sciences (P01 GM103770)

  • Paul A Garrity

National Institute of Allergy and Infectious Diseases (R01 AI22802)

  • Paul A Garrity

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: March 10, 2017
  2. Accepted: June 13, 2017
  3. Accepted Manuscript published: June 16, 2017 (version 1)
  4. Version of Record published: July 3, 2017 (version 2)

Copyright

© 2017, Knecht 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. Zachary A Knecht
  2. Ana F Silbering
  3. Joyner Cruz
  4. Ludi Yang
  5. Vincent Croset
  6. Richard Benton
  7. Paul A Garrity
(2017)
Ionotropic Receptor-dependent moist and dry cells control hygrosensation in Drosophila
eLife 6:e26654.
https://doi.org/10.7554/eLife.26654

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