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Updated: Jun 15, 2025
07:24
Combining Quantitative Food-intake Assays and Forcibly Activating Neurons to Study Appetite in Drosophila
Published on: April 24, 2018
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Opposing GPCR signaling programs protein intake setpoint in Drosophila
Guangyan Wu1, Tianji Ma1, Clare E Hancock1
1Department of Anatomy, University of California, San Francisco, San Francisco, CA 94158, USA.
Cell
|August 28, 2024
Summary
Flies adjust their protein intake setpoint based on sex and reproductive status. This crucial information is stored in hunger neurons as resting membrane potential, modulated by specific G protein-coupled receptor pathways.
Area of Science:
- Neuroscience
- Animal Behavior
- Molecular Biology
Background:
- Animals maintain physiological setpoints for essential needs like food, with deviations triggering motivated behaviors.
- The precise encoding and regulation of these setpoint values remain largely unknown across various motivated behaviors.
Purpose of the Study:
- To investigate how the protein intake setpoint is determined and modulated in Drosophila.
- To identify the neural circuits and molecular mechanisms underlying setpoint regulation.
Main Methods:
- Utilized a high-throughput feeding assay in Drosophila melanogaster.
- Measured resting membrane potential in protein hunger neurons.
- Investigated the role of two RFamide G protein-coupled receptor (GPCR) pathways.
Main Results:
- Demonstrated that protein intake setpoints vary between male, virgin female, and mated female flies.
- Showed that the protein intake setpoint information is encoded in the resting membrane potential of protein hunger neurons.
- Identified two GPCR pathways that oppositely tune resting membrane potential to regulate the setpoint.
Conclusions:
- The protein intake setpoint is a trackable physiological parameter encoded by neuronal resting membrane potential.
- Specific GPCR pathways coordinate to determine and adjust the protein intake setpoint based on physiological needs.
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