Mammalian cultured cells as a model system of peripheral circadian clocks.
The mammalian circadian system consists of multiple oscillators with basically hierarchical relationship, in which the hypothalamic suprachiasmatic nucleus (SCN) is the master pacemaker and the other oscillators in the periphery are subordinate. Although peripheral oscillators have been preceded by the SCN in circadian studies, accumulating data have revealed the importance and characteristics of peripheral oscillators. Cultured cell lines have also provided valuable information about intracellular mechanisms of circadian rhythms. This review outlines the properties of peripheral clocks in several perspectives such as the mechanisms of autonomous oscillations, the clock resetting, and the clock outputs, and describes the usefulness of immortalized cultured cells as a model system of mammalian circadian clocks by introducing some fruits of related works.
Tsuchiya
Yoshiki
Y
Department of Cell and Developmental Biology, Graduate School of Biostudies, Kyoto University, Sakyo-ku, Kyoto 606-8502.
Nishida
Eisuke
E
D000818:Animals; D001683:Biological Clocks / Q000502:physiology*; D002478:Cells, Cultured; D002940:Circadian Rhythm / Q000502:physiology*; D006801:Humans; D015398:Signal Transduction / Q000502:physiology; D013493:Suprachiasmatic Nucleus / Q000166:cytology* / Q000378:metabolism / Q000502:physiology*