Monomorphic Neurons Underlying Aggressive Actions in Drosophila

Monday, May 12, 2025

10:00 AM-12:00 PM

BIOMED PhD Thesis Defense

Title:
Monomorphic Neurons Underlying Aggressive Actions in Drosophila

Speaker:
Liangyu Tao, 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:
Aggression is a critical survival behavior that involves both sexually monomorphic (shared) and dimorphic (distinct) actions. How the brain implements these two types of actions is poorly understood. Historically, much of the work on Drosophila aggression has focused on the role of sexually dimorphic neurons involved in sensory and internal drives that result in long term modulation of dimorphic aggressive actions. However, the role of monomorphic neurons in acute aggression is largely unknown.

In this dissertation, I identify a single class of monomorphic neurons interneurons called CL062 that mediates acute aggression in both male and female flies. Although the aggressive actions are shared, the moment-by-moment implementation is sexually dimorphic. Through analyzing the full brain connectome of a female fly, I show that these neurons are likely part of a monomorphic circuit that functions parallel to the known dimorphic circuits. I then use a combination of in-vivo patch clamp electrophysiology, spatially restrictive optogenetics, connectome analysis and genetic perturbations to show three mechanisms underlying how CL062 control acute, directional aggression. First, I show that the CL062 neuron spiking predicts the probability of wing movement, but not the moment-by-moment behavior. Second, I show that a majority of CL062 neurons within a single hemisphere need to be activated for directional wing threat and thrusting. Third, I show that repeated activation of CL062 neurons drives short timescale behavioral plasticity. These results highlight the diversity of neural circuits underlying flexible implementation of aggression and set the groundwork for future studies into the neural principals and mechanisms behind this flexibility.  

Contact Information

Natalia Broz
njb33@drexel.edu