Genetic clock

Periodicity and Rhythm of Cell Biochemical Activity and Its Genetic Programming. The Genetic Clock... 

Ko CH, Takahashi JS (2006) Molecular components of the mammalian circadian clock. Hum Mol Genet 15 Spec No 2 R271-R277... 

Y. BesshoandR. Kageyama, Oscillations, clocks and segmentation. Curr. Opin. Genet. Dev. 13, 379-384 (2003). 

First, the SCN of mCrj1 mCry2r mice appears electrically arrhythmic, independent of whether animals had been kept under a light—dark cycle or in constant darkness. This finding provides direct genetic evidence that mCRY proteins are indispensable for circadian rhythmicity of electrical activity in SCN neurons. Thus, an intact circadian clockwork appears prerequisite for circadian electrical activity in SCN neurons. This finding seems somewhat contradictory to a recent study of Nakamura et al (2002), who demonstrated electrical rhythmicity in SCN slices from arrhythmic homozygous Clock mutant mice. However, this... 

Takahashi In our original phenotypic description of clock where we say that the rhythm disappears after about two weeks, this is the average of a group of animals on that particular genetic background. 

Young MW, Kay SA 2001 Time zones a comparative genetics of circadian clocks. Nat Rev Genet 2 702-715... 

The discovery of peripheral oscillators in mammals has raised the question of how the SCN master pacemaker synchronizes these subsidiary clocks. Current evidence suggests that feeding time is the dominant eitgeber for most peripheral oscillators. The molecular mechanisms involved in food-dependent phase resetting are not yet understood, and deciphering the signalHng pathways involved will probably require many additional years of intense genetic and biochemical research. 

Pando MP, Morse D, Cermakian N, Sassone-Corsi P 2002 Phenotypic rescue of a peripheral clock genetic defect via SCN hierarchical dominance. Cell 110 107—117 Plautz JD, Kaneko M, Hall JC, Kay SA 1997 Independent photoreceptive circadian clocks throughout Drosophila. Science 278 1632-1635... 

Allada R, Emery P, Takahashi JS, Rosbash M 2001 Stopping time the genetics of fly and mouse circadian clocks. Annu Rev Neurosci 24 1091-1119 Blau J, Young MW 1999 Cycling vrille expression is required for a functional Drosophila clock. Cell 99 661-671... 

Liu Y, Loros J, Dunlap JC 2000 Phosphorylation of the Neurospora clock protein FREQUENCY determines its degradation rate and strongly influences the period length of the circadian clock. Proc Natl Acad Sci USA 97 234—239 Loros JJ, Dunlap JC 2001 Genetic and molecular analysis of circadian rhythms in Neurospora. Annu Rev Physiol 63 757—794... 

The identification of putative mammalian clock genes by both homology and mutagenesis screening is described elsewhere in this volume. It represents an enormous achievement, and already it is possible to speak of the new circadian biology in which molecular genetics can be used to understand and re-interpret more classical, black-box descriptions of mammalian circadian behaviour. A key component of this analysis is to understand the behaviour of the clock genes, and... 

Van Gelder Have you looked in any of the clock mutants at where the TGFa levels are pegged when the clock is non-functional genetically ... 

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