We use the Drosophila larval brain to examine neural stem cells.
In the Mulligan lab we use the common fruit fly, Drosophila melanogaster, to investigate interactions between epigenetic factors and genes during neural development. The purpose of our research is to identify environmental factors that may confer risk or increase the severity of neurodevelopmental disorders (NDD), like autism and Fragile X syndrome, in humans that have genetic risk factors for NDDs. Many of the molecular networks that govern human brain development are conserved in Drosophila, meaning this research is relevant to human health and disease.
Analyzing the convergence of autism risk genes and chemical exposures in a Drosophila model of autism
Characterizing the gut-brain-axis in a Drosophila model of autism
Courtship Analysis & Imaging Neural Structures
Altering brain development can change behavior. There are different ways to examine fruit fly behavior; in our lab we use the courtship assay. The fruit fly courtship ritual is an innate behavior that is often disrupted when brain development is impaired. The courtship assay is a test that allows us to measure courtship differences. The normal sequence of courtship behaviors is: orientation (toward female), leg tapping, wing extension, licking, attempted copulation, and successful copulation. When differences are observed, we can perform cellular and molecular analyses of brains and neurons to understand how specific genes and environmental factors have disrupted neural function. Above is a short excerpt of a courtship assay.
How can you examine the nervous system of a fruit fly? To examine how neural development has been impaired, we use methods that allow us to fluorescently label different neural structures and even different types of neurons. This labeling technique, combined with fine dissection skills and confocal microscopy, allows us to make comparisons between flies that are wildtype (genetically "normal") or unexposed to chemicals to flies that have specific genetic disruptions combined with chemical exposures. We can determine, for example, if there are problems with axon growth and guidance or synapse formation. Above is an image of the mushroom body, a neural structure within the adult fruit fly brain.