Activity-dependent development of the glial network in Drosophila ventral nerve cord

University Of Arizona, Tucson AZ

Investigators

Abstract

Glial cells are non-electrical brain cells that work together with neurons to make the nervous system function. Glial cells can sense the activity of neurons and control it, help to guide the wiring of the networks of neurons, are involved in learning and memory, and provide vital metabolic support for neurons, so mapping only the connections and activity of neurons in the brain is not enough to understand how the brain works. Glial cells must be included. This project will: (1) detail the anatomy of individual glial cells and make a comprehensive map of the glial cells and the network they form; and (2) examine the effect of disrupting neuronal activity on the development of glial cells and their network. The work will be carried out in the nervous system of the fruit fly Drosophila, a genetically powerful system in which development and function of neurons have been well studied. Because Drosophila shares many aspects of cellular development with humans, an understanding of the developmental relationship between neurons and glial cells in this advantageous model system will lead toward a fuller understanding of normal development and mature functioning of the human brain. The project also includes outreach to the public via K-12 classroom visits and public events, and a multi-station hands-on Brain booth at a large annual festival. Several undergraduate students each year will be trained in the laboratory. A new course for undergraduates about glial cells will be developed that will include creation of a website on glial cells that will serve as a resource for the academic community. This project will examine the hypothesis that the glial network is shaped by neuronal activity during development. The work will be carried out in the ventral nerve cord of the 3rd-instar Drosophila larva. Previous work has developed this system to specifically address neuron development, but the developing glial network in this system has not been characterized. Thus, this is a particularly advantageous animal model ripe for investigating the effects of neuron activity on glial development. The project will provide a high-resolution reconstruction of the glial network in the ventral nerve cord using genetically labeled and dye-filled glial cells, electron microscopy, and 3D reconstruction of glial cells in normally developing animals and in animals in which neuronal activity in the nerve cord has been blocked or reduced using genetic manipulations during larval development.