The circadian clock in old Drosophila melanogaster

A growing body of evidence indicates that one of the age-associated changes in the central nervous system that affect most old people is the loss of f unction of the circadian clock system. This loss results in impaired timing and quality of sleep, with consequent cognitive and other behavior problem s. Failure of the clock contributes to the difficulties encountered with Al zheimer's disease. It also results in adverse changes in the hormonal regul ation of intermediary metabolism, stress resistance and sexual function. Dr osophila melanogaster is proposed as a model organism where this age-relate d change may be studied more readily. Circadian patterns are disrupted in D rosophila, with considerable differences between strains. In addition a fus ion gene product of a key gene involved in the clock (per), and Green Fluor escent Protein, shows a 50% fall with age.