Figure 6. Model for the involvement of the circadian clock and circadian clock proteins in the control of aging. (a) The circadian clock synchronizes multiple metabolic processes in the organism and regulates the expression and activity of circadian clock proteins, which have unique physiological functions. Disruption of circadian clock functions will affect both activity and expression of circadian clock proteins and can contribute to aging; (b) BMAL1 can regulate aging through different pathways: through the circadian clock, through functional interactions with CLOCK, through interaction with NPAS2, and through circadian clock and CLOCK/NPAS2-independent mechanisms (indicated by X).