2. Molecular Architecture of the Circadian Clock in Mammals

Abstract

The molecular mechanism of circadian clocks in mammals is generated by a set of genes forming a transcriptional autoregulatory feedback loop. The “core clock genes” include: Clock, Bmal1, Per1, Per2, Cry1 and Cry2. The discovery of “clock genes” led to the realization that circadian gene expression is widespread throughout the body and that the clock is cell autonomous. The cellular autonomy of circadian clocks has raised a number of questions concerning synchronization and coherence of rhythms at the cellular level as well as circadian organization at the systems level. The role of clocks in peripheral tissues has a number of important implications for disease.