Drosophila TRPg is required in neuroendocrine cells for post-ingestive food selection
- Kookmin University, Republic of Korea
- Johns Hopkins University School of Medicine, United States
- University of California, Santa Barbara, United States
Abstract
The mechanism through which the brain senses the metabolic state, enabling an animal to regulate food consumption, and discriminate between nutritional and non-nutritional foods is a fundamental question. Flies choose the sweeter non-nutritive sugar, L-glucose, over the nutritive D-glucose if they are not starved. However, under starvation conditions, they switch their preference to D-glucose, and this occurs independent of peripheral taste neurons. Here, we found that eliminating the TRPγ channel impairs the ability of starved flies to choose D-glucose. This food selection depends on trpγ expression in neurosecretory cells in the brain that express Diuretic hormone 44 (DH44). Loss of trpγ increases feeding, alters the physiology of the crop, which is the fly stomach equivalent, and decreases intracellular sugars and glycogen levels. Moreover, survival of starved trpγ flies is reduced. Expression of trpγ in DH44 neurons reverses these deficits. These results highlight roles for TRPγ in coordinating feeding with the metabolic state through expression in DH44 neuroendocrine cells.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for Figures 1-7, and Figure supplements 1-7.
Article and author information
Author details
Funding
National Institute on Deafness and Other Communication Disorders (DC007864)
- Craig Montell
National Institute of Allergy and Infectious Diseases (AI65575)
- Craig Montell
National Institute of Allergy and Infectious Diseases (AI169386)
- Craig Montell
National Research Foundation of Korea (NRF-2018R1A2B6004202)
- Youngseok Lee
National Research Foundation of Korea (NRF-2016R1D1A1B03931273)
- Youngseok Lee
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2022, Dhakal 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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Drosophila TRPg is required in neuroendocrine cells for post-ingestive food selection
eLife 11:e56726.
https://doi.org/10.7554/eLife.56726
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