The neuromodulatory role of dopamine signaling on locomotion of Drosophila Larvae

Project Summary/Abstract – Stephanie Dancausse Sensory experiences are detected by the peripheral nervous system (PNS) and then transmitted to the central nervous system (CNS) where neurons within the brain respond to produce appropriate behavioral output. These behavioral outputs include locomotion whose underlying neural mechanisms are conserved throughout many taxa. Sensory experiences or the action of neurotransmitters can act on the neural circuits that carry out locomotion through various mechanisms to modulate its behavioral features. Dopamine, a neurotransmitter in the CNS, is known to act as a neuromodulator of motor output, however the exact neural circuits involved and the mechanisms by which the neural activity modulates locomotion remain unknown. To do this, I will employ advanced genetic tools to manipulate dopaminergic neuron activity in the CNS and record the larvae’s resultant behavior with a novel robotic rig that allows for long-term behavioral assays on the order of days. I find that larvae do modulate aspects of their locomotive behavior in response to pharmacological manipulation of the dopaminergic pathway. In vivo neural confocal microscopy and calcium imaging will be conducted to probe the descending neural targets in the neural circuit that control larval locomotion. Manipulations of identified neurons will be carried using genetic tools to demonstrate their roles in the behaviors characterized. In this project I will 1) determine the behavioral impact of dopamine signaling in the CNS through genetic manipulations and 2) identify and study the downstream targets of dopamine neurons that control larval locomotion. These experiments will use novel approaches and methods to understand the neuromodulatory role of dopamine signaling on larval locomotion.