PERIOD2::LUCIFERASE real-time reporting of circadian dynamics reveals persistent circadian oscillations in mouse peripheral tissues.
- Seung-Hee Yoo, S. Yamazaki, J. Takahashi
- BiologyProceedings of the National Academy of Sciences…
- 13 April 2004
It is demonstrated that peripheral tissues express self-sustained, rather than damped, circadian oscillations and the existence of organ-specific synchronizers of circadian rhythms at the cell and tissue level is suggested.
Resetting central and peripheral circadian oscillators in transgenic rats.
It is hypothesize that a self-sustained circadian pacemaker in the SCN entrains circadian oscillators in the periphery to maintain adaptive phase control, which is temporarily lost following large, abrupt shifts in the environmental light cycle.
Entrainment of the circadian clock in the liver by feeding.
It is demonstrated that feeding cycles can entrain the liver independently of the SCN and the light cycle, and the need to reexamine the mammalian circadian hierarchy is suggested, raising the possibility that peripheral circadian oscillators like those in the liver may be coupled to theSCN primarily through rhythmic behavior, such as feeding.
Positional syntenic cloning and functional characterization of the mammalian circadian mutation tau.
The tau mutation is a semidominant autosomal allele that dramatically shortens period length of circadian rhythms in Syrian hamsters and the mechanism by which the mutation leads to the observed aberrant circadian phenotype in mutant animals is proposed.
Transplanted suprachiasmatic nucleus determines circadian period.
The pacemaker role of the suprachiasmatic nucleus in a mammalian circadian system was tested by neural transplantation by using a mutant strain of hamster that shows a short circadian period to restore circadian rhythms to arrhythmic animals whose own nucleus had been ablated.
The circadian rhythm of body temperature
Circadian Rhythms in Isolated Brain Regions
The results indicate that the brain contains multiple, damped circadian oscillators outside the SCN, and the phasing of these oscillators to one another may play a critical role in coordinating brain activity and its adjustment to changes in the light cycle.
A mutation of the circadian system in golden hamsters.
A mutation has been found that dramatically shortens the period of the circadian locomotor rhythm of golden hamsters, and animals that carry the mutant alleles exhibit abnormal entrainment to 24-hour light:dark cycles or are unable to entrain.
Circadian Rhythms in Cultured Mammalian Retina
Cultured neural retinas of the golden hamster exhibited circadian rhythms of melatonin synthesis for at least 5 days at 27°C, and retinas from hamsters homozygous for the circadian mutation tau showed a shortened free-running period ofmelatonin synthesis.