The sound and the fly: Drosophila in biomedical research on human hearing

Deep biochemical and cellular similarities exist between Drosophila and vertebrates in the development and function of all organs. Despite their morphological differences, it is considered ever more likely that the hearing sensory cells have a common evolutionary origin and that consequently the molecular mechanisms that govern their functions are at least partially conserved. Thanks to transgenesis techniques and to the rich collection of mutant stocks well characterized from genetic, molecular and physiological points of view, Drosophila provides the means to test in vivo vertebrate gene functions in known metabolic and cellular pathways. In addition, the search for sequence homologies between human and Drosophila genes has allowed the identification of many disease genes in the human auditory system. These results indicate that Drosophila is a good model for the study of the genes that cause deafness in humans, and offers the possibility of using the numerous and sophisticated genetic tools of the insect to decipher how mechanical signals are elaborated by the auditory system. In this review, contributions to biomedical research from studies on Drosophila mutants are briefly summarized following a concise account on the fruitfly life cycle, tools and available resources. Particular attention is paid to studies on the genetic control of hearing mechanisms in the insect. The acquired knowledge will help confront some vertebrate hearing diseases on a molecular basis.