Nociceptive interneurons control modular motor pathways to promote escape behavior in Drosophila
Abstract
Rapid and efficient escape behaviors in response to noxious sensory stimuli are essential for protection and survival. Yet, how noxious stimuli are transformed to coordinated escape behaviors remains poorly understood. In Drosophila larvae, noxious stimuli trigger sequential body bending and corkscrew-like rolling behavior. We identified a population of interneurons in the nerve cord of Drosophila, termed Down-and-Back (DnB) neurons, that are activated by noxious heat, promote nociceptive behavior, and are required for robust escape responses to noxious stimuli. Electron microscopic circuit reconstruction shows that DnBs are targets of nociceptive and mechanosensory neurons, are directly presynaptic to pre-motor circuits, and link indirectly to Goro rolling command-like neurons. DnB activation promotes activity in Goro neurons, and coincident inactivation of Goro neurons prevents the rolling sequence but leaves intact body bending motor responses. Thus, activity from nociceptors to DnB interneurons coordinates modular elements of nociceptive escape behavior.
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Author details
Funding
National Science Foundation (Graduate Research Fellowship)
- Anita Burgos
National Institutes of Health (NS090909-01)
- Anita Burgos
Howard Hughes Medical Institute
- Marta Zlatic
National Institutes of Health (NS061908)
- Wesley B Grueber
National Institutes of Health (GM086458)
- W Daniel Tracey
National Institutes of Health (NS086564)
- Wesley B Grueber
Howard Hughes Medical Institute
- Albert Cardona
Thompson Family Foundation (Innovation Award)
- Grace Ji-eun Shin
- Wesley B Grueber
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Burgos 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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