Synaptic transmission parallels neuromodulation in a central food-intake circuit
- LIMES Institute, Germany
- Janelia Research Campus, Howard Hughes Medical Institute, United States
Abstract
NeuromedinU is a potent regulator of food intake and activity in mammals. In Drosophila, neurons producing the homologous neuropeptide hugin regulate feeding and locomotion in a similar manner. Here, we use EM-based reconstruction to generate the entire connectome of hugin-producing neurons in the Drosophila larval CNS. We demonstrate that hugin neurons use synaptic transmission in addition to peptidergic neuromodulation and identify acetylcholine as a key transmitter. Hugin neuropeptide and acetylcholine are both necessary for the regulatory effect on feeding. We further show that subtypes of hugin neurons connect chemosensory to endocrine system by combinations of synaptic and peptide-receptor connections. Targets include endocrine neurons producing DH44, a CRH-like peptide, and insulin-like peptides. Homologs of these peptides are likewise downstream of neuromedinU, revealing striking parallels in flies and mammals. We propose that hugin neurons are part of an ancient physiological control system that has been conserved at functional and molecular level.
Article and author information
Author details
Casey M Schneider-Mizell
Michael J Pankratz
Funding
Howard Hughes Medical Institute
- Michael J Texada
- Casey M Schneider-Mizell
- Haluk Lacin
- Feng Li
- Richard D Fetter
- James W Truman
- Albert Cardona
Deutsche Forschungsgemeinschaft
- Philipp Schlegel
- Anton Miroschnikow
- Andreas Schoofs
- Sebastian Hückesfeld
- Marc Peters
- Michael J Pankratz
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2016, Schlegel 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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Synaptic transmission parallels neuromodulation in a central food-intake circuit
eLife 5:e16799.
https://doi.org/10.7554/eLife.16799
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