Understanding neural functions inevitably involves arguments traversing multiple levels of hierarchy in biological systems. However, finding new components or mechanisms of such systems is extremely time-consuming due to the low efficiency of currently available functional screening techniques. To overcome such obstacles, we utilize pan-neuronal calcium imaging to broadly screen the activity of the C. elegans nervous system in response to thermal stimuli. A single pass of the screening procedure can identify much of the previously reported thermosensory circuitry as well as identify several unreported thermosensory neurons. Among the newly discovered neural functions, we investigated the role of the AWCOFF neuron in thermal nociception. Combining functional calcium imaging and behavioral assays, we show that AWCOFF is essential for avoidance behavior following noxious heat stimulation by modifying the forward-to-reversal behavioral transition rate. We also show that the AWCOFF signals adapt to repeated noxious thermal stimuli and quantify the corresponding behavioral adaptation.
- Jarlath D Byrne Rodgers
- William S Ryu
- Ippei Kotera
- Nhat Anh Tran
- Donald Fu
- William S Ryu
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Oliver Hobert, Howard Hughes Medical Institute, Columbia University, United States
© 2016, Kotera 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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