Distinct combinations of variant ionotropic glutamate receptors mediate thermosensation and hygrosensation in Drosophila
- Brandeis University, United States
- University of Lausanne, Switzerland
- Harvard University, United States
- University of Miami, United States
Abstract
Ionotropic Receptors (IRs) are a large subfamily of variant ionotropic glutamate receptors present across Protostomia. While these receptors are most extensively studied for their roles in chemosensory detection, recent work has implicated two family members, IR21a and IR25a, in thermosensation in Drosophila. Here we characterize one of the most evolutionarily deeply conserved receptors, IR93a, and show that it is co-expressed and functions with IR21a and IR25a to mediate physiological and behavioral responses to cool temperatures. IR93a is also co-expressed with IR25a and a distinct receptor, IR40a, in a discrete population of sensory neurons in the sacculus, a multi-chambered pocket within the antenna. We demonstrate that this combination of receptors is required for neuronal responses to dry air and behavioral discrimination of humidity differences. Our results identify IR93a as a common component of molecularly and cellularly distinct IR pathways important for thermosensation and hygrosensation in insects.
Article and author information
Author details
Funding
National Institutes of Health (F31 DC015155 01A1)
- Zachary A Knecht
National Institutes of Health (F32 NS077835)
- Mason Klein
Boehringer Ingelheim Fonds (PhD Fellowship)
- Rati Bell
European Research Council (Starting Independent Researcher Grant 205202)
- Richard Benton
European Research Council (Consolidator Grant 915094)
- Richard Benton
National Institutes of Health (F32 GM113318)
- Gonzalo Budelli
National Institutes of Health (P01 GM103770)
- Aravinthan DT Samuel
- 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
- Mani Ramaswami, Trinity College Dublin, Ireland
Version history
- Received: May 17, 2016
- Accepted: September 21, 2016
- Accepted Manuscript published: September 22, 2016 (version 1)
- Accepted Manuscript updated: September 23, 2016 (version 2)
- Version of Record published: October 5, 2016 (version 3)
Copyright
© 2016, 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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Distinct combinations of variant ionotropic glutamate receptors mediate thermosensation and hygrosensation in Drosophila
eLife 5:e17879.
https://doi.org/10.7554/eLife.17879
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