11 Yeast, a Feast: The Fruit Fly Drosophila as a Model Organism for Research into Aging

Research into aging has been galvanized by the discovery of mutations in single genes that extend life span and evolutionary conservation of their effects. An environmental intervention—dietary restriction—also extends life span in evolutionarily diverse animals. These discoveries have opened the way to using laboratory model organisms to understand human aging. Invertebrate species, budding yeast Saccharomyces cerevisiae , the nematode worm Caenorhabditis elegans , and the fruit fly Drosophila melanogaster , have a vital role in this process of discovery. Their ease of culture and handling in the laboratory and short life spans (~3 days in yeast, ~3 weeks in the worm, and ~3 months in Drosophila ) mean that much more rapid progress can be made than in the mouse, whose life spans are about 3 years. Completion of the genome sequences for the invertebrates and their closely related species, together with the development of many genetic and other resources, also make them powerful experimental systems. Each of these organisms has strengths and weaknesses for research into aging. We highlight here some of the particular strengths of Drosophila and uses to which they have been put and could be put in the future. The jaw-dropping genetics applied to a complex tissue structure approaching that of vertebrates leaves Drosophila flying at the front edge of aging research. The time has long passed when a full review of the biology of aging in the fruit fly D. melanogaster could be usefully accommodated in a single chapter. Drosophila has been an established model organism for...