A conserved neuropeptide system links head and body motor circuits to enable adaptive behavior
- University of Massachusetts Medical School, United States
- Assumption University, United States
- University of Massachusetts Chan Medical School, United States
- University of Leuven (KU Leuven), Belgium
Abstract
Neuromodulators promote adaptive behaviors that are often complex and involve concerted activity changes across circuits that are often not physically connected. It is not well understood how neuromodulatory systems accomplish these tasks. Here we show that the C. elegans NLP-12 neuropeptide system shapes responses to food availability by modulating the activity of head and body wall motor neurons through alternate G-protein coupled receptor (GPCR) targets, CKR-1 and CKR-2. We show ckr-2 deletion reduces body bend depth during movement under basal conditions. We demonstrate CKR-1 is a functional NLP-12 receptor and define its expression in the nervous system. In contrast to basal locomotion, biased CKR-1 GPCR stimulation of head motor neurons promotes turning during local searching. Deletion of ckr-1 reduces head neuron activity and diminishes turning while specific ckr-1 overexpression or head neuron activation promote turning. Thus, our studies suggest locomotor responses to changing food availability are regulated through conditional NLP-12 stimulation of head or body wall motor circuits.
Data availability
All data generated or analyzed during this study are included in the manuscript and supporting files; source data files are provided as supplemental files.
Article and author information
Author details
Funding
NIH (R21NS093492)
- Michael M Francis
European Research Council (340318)
- Isabel Beets
Research Foundation Flanders Grant (G0C0618N)
- Isabel Beets
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Ramachandran 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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A conserved neuropeptide system links head and body motor circuits to enable adaptive behavior
eLife 10:e71747.
https://doi.org/10.7554/eLife.71747
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