Role of Dopaminergic Descending Neurons in the Control of Locomotion in Drosophila

Tuesday, May 27, 2025

1:00 PM-3:00 PM

BIOMED PhD Thesis Defense

Title:
Role of Dopaminergic Descending Neurons in the Control of Locomotion in Drosophila

Speaker:
Ninghan Wang, PhD Candidate
School of Biomedical Engineering, Science and Health Systems
Drexel University

Advisor:
Vikas Bhandawat, PhD
Associate Professor
School of Biomedical Engineering, Science and Health Systems
Drexel University

Details:
Dopaminergic neurons are essential for regulating a wide range of functions, including reward processing, learning, and locomotion. A specific subset – dopaminergic descending neurons (DADNs) – originates in the brain and projects to the spinal cord or ventral nerve cord in invertebrates, influencing motor control. While previous studies using pharmacological and optogenetics strategies suggest DADNs are critical for movement, their in vivo function and the role of dopamine receptors during behavior remain poorly understood.

In this research, we chose to address this problem in Drosophila melanogaster or fruit flies. There are only two DADNs which make understanding their role in motor control tractable. Using electrophysiological recordings combined with optogenetic manipulation, behavioral tracking, and the powerful genetic toolkit in flies, we found that 1) DADNs’ neuronal activity is dynamic and exhibits a strong relationship with leg movements but a weak relationship with locomotion; 2) both activation and inactivation of these neurons can elicit an increase in behavioral output; 3) and this effect is modulated by the inhibitory dopamine receptor Dop2R which is diffusely expressed in both brain and ventral nerve cord.

This research provides valuable insights into the mechanism by which DADNs modulate motor circuits at cellular and network levels, bringing an advanced understanding of their role in motor control during locomotion.

Contact Information

Natalia Broz
njb33@drexel.edu