Circadian regulation of gene expression in animals

Circadian timekeepers reside in most body cells of Drosophila and mammals. The discovery of new clock genes suggests that circadian oscillations are generated by interconnected feedback loops employing transcriptional and post-translational mechanisms. In mammals, a master pacemaker localized in the suprachiasmatic nucleus synchronizes peripheral clocks via humoral cues. However, restricted feeding can uncouple peripheral oscillators from the suprachiasmatic pacemaker.