The Linda and Jack Gill Center for Biomolecular Science, Indiana University, Bloomington, United States; Department of Biology, Indiana University, Bloomington, United States
Marta Zlatic
Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
Department of Neuroscience, Columbia University Medical Center, New York, United States; Department of Physiology and Cellular Biophysics, Columbia University Medical Center, New York, United States; Mortimer B. Zuckerman Mind Brain Behavior Institute, Columbia University, New York, United States
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.
