Chloride-dependent mechanisms of multimodal sensory discrimination and nociceptive sensitization in Drosophila
- Georgia State University, United States
Abstract
Individual sensory neurons can be tuned to many stimuli, each driving unique, stimulus-relevant behaviors, and the ability of multimodal nociceptor neurons to discriminate between potentially harmful and innocuous stimuli is broadly important for organismal survival. Moreover, disruptions in the capacity to differentiate between noxious and innocuous stimuli can result in neuropathic pain. Drosophila larval Class III (CIII) neurons are peripheral noxious cold nociceptors and innocuous touch mechanosensors; high levels of activation drive cold-evoked contraction (CT) behavior, while low levels of activation result in a suite of touch-associated behaviors. However, it is unknown what molecular factors underlie CIII multimodality. Here, we show that the TMEM16/anoctamins subdued and white walker (wwk; CG15270) are required for cold-evoked CT, but not for touch-associated behavior, indicating a conserved role for anoctamins in nociception. We also evidence that CIII neurons make use of atypical depolarizing chloride currents to encode cold, and that overexpression of ncc69-a fly homologue of NKCC1-results in phenotypes consistent with neuropathic sensitization, including behavioral sensitization and neuronal hyperexcitability, making Drosophila CIII neurons a candidate system for future studies of the basic mechanisms underlying neuropathic pain
Data availability
All data generated or analyzed during this study are included in the manuscript. We have plotted all data such that individual data points can be seen. Additionally, we have included heatmap representations of cold-evoked larval behavior for every single larva used in this study (see supplemental figures). Class III neuron-specific transcriptomic data has been deposited in GEO under accession number GSE69353. Accession numbers for sequences used in phylogenetic analysis are presented in the relevant figure. Raw data and sequence files are available in Dryad.
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Choride-dependent mechanisms of multimodal sensory discrimination and nociceptive sensitization in DrosophilaDryad Digital Repository, doi:10.5061/dryad.dncjsxm3h.
Article and author information
Author details
Nathaniel J Himmel
Gennady S Cymbalyuk
Funding
National Institutes of Health (NS115209)
- Gennady S Cymbalyuk
- Daniel N Cox
National Institutes of Health (NS117087)
- Nathaniel J Himmel
Georgia State University (Honeycutt Fellowship)
- Nathaniel J Himmel
- Atit A Patel
Georgia State University (Brains & Behavior Fellowship)
- Nathaniel J Himmel
- Atit A Patel
- Jamin M Letcher
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2023, Himmel 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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