title: [Molecular oscillatory machinery of circadian rhythms].
abstract: Many metabolic and physiological processes display daily rhythms oscillated by the internal circadian clock system. This rhythm is generated by interlocked transcription-(post) translation feedback loops of clock genes: the core oscillatory loop, being composed of CLOCK/BMAL1 heterodimer activating the expressions of PER and CRY that directly repress CLOCK/BMAL1, is accompanied by accessory loops consisted with REV-ERB nuclear receptor repressing Bmal1 or with DBP competing with E4BP4 on D-box site. These clock proteins are regulated by phosphorylation and ubiquitination (PER/CRY), and acetylation (CLOCK/BMAL1). Recently, a deacetylating protein SIRT1 mediated metabolic pathway is discovered to be interlocked with core oscillatory loop via Nampt expression, a late-limiting enzyme in NAD+ salvage pathway. Since many key-step enzymes of metabolisms are regulated by the circadian clock, circadian clock system may intimately link to cellular metabolism.
authors: Department of Systems Biology, Graduate School of Pharmaceutical Sciences, Kyoto University.
authors: Yoshiaki
authors: Y
authors: Yamaguchi
authors: Hitoshi
authors: H
authors: Okamura
mesh_terms: D000818:Animals; D002843:Chromatin / Q000378:metabolism; D057906:Circadian Clocks; D002940:Circadian Rhythm; D025461:Feedback, Physiological; D006801:Humans; D013493:Suprachiasmatic Nucleus / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism
chemical_list: D002843:Chromatin; D014157:Transcription Factors