Functioning of Glia and Neurodegeneration in Drosophila melanogaster

The views on the role of glial tissue have changed greatly since the first studies in the field. The cells once regarded as "cell glue" have been shown to play important roles in development, trophic processes, production of navigation signals for axon growth, electric insulation of neurons, creation of a barrier between the brain and the hemolymph, control of extracellular homeostasis, and physiological functioning of the brain. Researchers all over the world are currently turning to Drosophila melanogaster, a well-characterized model organism in genetics, in order to investigate multiple molecular aspects of neurodegeneration processes, since the modeling of neurodegeneration mechanisms in Drosophila has a number of advantages. Fruit flies with a mutation in the swiss cheese (sws) gene show degeneration of neurons and surface glia cells of the optical lobe, and the protein product of the sws gene is essential for maintaining the functionality and integrity of the fly brain. The present review addresses the role of glial cells in Drosophila brain development and in the functioning of the adult fly brain as well as the pattern of expression of the gene sws and the distribution of the product of this gene in neurons and glia.