A Neuronal Pathway that Commands Deceleration in DrosophilaLarval Light-Avoidance
1Department of Neurobiology, Key Laboratory of Medical Neurobiology of the Ministry of Health of China, Key Laboratory of Neurobiology, Zhejiang University School of Medicine, Hangzhou 310058, China
2 Qiushi Academy for Advanced Studies, Zhejiang University, Hangzhou 310007, China
3 Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 22011, USA
Abstract
When facing a sudden danger or aversive condition while engaged in on-going forward motion, animals transiently slow down and make a turn to escape. The neural mechanisms underlying stimulation-induced deceleration in avoidance behavior are largely unknown. Here, we report that in Drosophila larvae, light-induced deceleration was commanded by a continuous neural pathway that included prothoracicotropic hormone neurons, eclosion hormone neurons, and tyrosine decarboxylase 2 motor neurons (the PET pathway). Inhibiting neurons in the PET pathway led to defects in light-avoidance due to insufficient deceleration and head casting. On the other hand, activation of PET pathway neurons specifically caused immediate deceleration in larval locomotion. Our findings reveal a neural substrate for the emergent deceleration response and provide a new understanding of the relationship between behavioral modules in animal avoidance responses.
Keywords
Drosophila; Larva; Deceleration; Light avoidance; EH neurons; PTTH neurons; Tdc2 motor neurons
