The mammalian circadian system is a complex hierarchical temporal network which is
organized around an ensemble of uniquely coupled cells comprising the principal circadian
pacemaker in the suprachiasmatic nucleus of the hypothalamus. This central pacemaker is
entrained each day by the environmental light/dark cycle and transmits synchronizing cues
to cell-autonomous oscillators in tissues throughout the body. Within cells of the central
pacemaker and the peripheral tissues, the underlying molecular mechanism by which …