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  • Review Article
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Molecular mechanisms at the core of the plant circadian oscillator

Abstract

Circadian clocks are endogenous timekeeping networks that allow organisms to align their physiology with their changing environment and to perform biological processes at the most relevant times of the day and year. Initial feedback-loop models of the oscillator have been enriched by emerging evidence highlighting the increasing variety of factors and mechanisms that contribute to the generation of rhythms. In this Review, we consider the two major input pathways that connect the circadian clock of the model plant Arabidopsis thaliana to its environment and discuss recent advances in understanding of how transcriptional, post-translational and post-transcriptional mechanisms contribute to clock function.

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Figure 1: Environmental signals are integrated by the central oscillator to coordinate multiple physiological processes.
Figure 2: Transcriptional feedback loops at the core of the circadian oscillator in Arabidopsis thaliana.
Figure 3: Post-translational regulatory circuits within the clock of Arabidopsis thaliana.

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Acknowledgements

We thank S. Sanchez, D. Nagel and J. Gallego-Bartolome for critical reading of the manuscript. Work at the laboratory of S.A.K. is supported by the National Institute of General Medical Sciences of the National Institutes of Health under award numbers RO1GM067837 and RO1GM056006. We apologize to our colleagues whose work could not be cited, owing to space limitations.

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Correspondence to Steve A Kay.

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Nohales, M., Kay, S. Molecular mechanisms at the core of the plant circadian oscillator. Nat Struct Mol Biol 23, 1061–1069 (2016). https://doi.org/10.1038/nsmb.3327

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