Molecular basis of fatty acid taste in Drosophila
Abstract
Behavioral studies have established that Drosophila appetitive taste responses to towards fatty acids are mediated by sweet sensing Gustatory Receptor Neurons (GRNs). Here we show that sweet GRN activation requires the function of the Ionotropic Receptor genes IR25a, IR76b and IR56d. The former two IR genes are expressed in several neurons per sensilla, while IR56d expression is restricted to sweet GRNs. Importantly, loss of appetitive behavioral responses to fatty acids in IR25a and IR76b mutant flies can be completely rescued by expression of respective transgenes in sweet GRNs. Interestingly, appetitive behavioral responses of wild type flies to hexanoic acid reach a plateau at ~1%, but decreases with higher concentration, a property mediated through an IR25a/IR76b independent activation of bitter GRNs by hexanoic acid. With our previous report on sour taste, our studies suggest that IR-based receptors mediate different taste qualities through cell-type specific IR subunits.
Article and author information
Author details
Funding
National Institutes of Health (RO1GMDC05606)
- Hubert O Amrein
National Institutes of Health (RO1DC13967)
- Hubert O Amrein
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
Publication history
- Received: July 3, 2017
- Accepted: December 8, 2017
- Accepted Manuscript published: December 12, 2017 (version 1)
- Version of Record published: December 29, 2017 (version 2)
Copyright
© 2017, Ahn 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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