Abstract
Circadian clocks consist of three elements: entrainment pathways (inputs), the mechanism generating the rhythmicity (oscillator), and the output pathways that control the circadian rhythms. It is difficult to assign molecular clock components to any one of these elements. Experiments show that inputs can be circadianly regulated1,2,3 and outputs can feed back on the oscillator4,5. Mathematical simulations indicate that under- or overexpression of a gene product can result in arrhythmicity, whether the protein is part of the oscillator or substantially part of a rhythmically expressed input pathway6. To distinguish between these two possibilities, we used traditional circadian entrainment protocols7,8 on a genetic model system, Neurospora crassa.
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Acknowledgements
This work is dedicated to the memory of J. Aschoff. We thank V. Schiewe, A. Kohnert and G. Meyer for excellent technical assistance; the members of the Woody Hastings lab for comments on the manuscript; and the DFG, the Meyer-Struckmann-Stiftung and the Münchner Medizinische Wochenschrift for support.
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Merrow, M., Brunner, M. & Roenneberg, T. Assignment of circadian function for the Neurospora clock gene frequency. Nature 399, 584–586 (1999). https://doi.org/10.1038/21190
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DOI: https://doi.org/10.1038/21190
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