Network balance via CRY signalling controls the Arabidopsis circadian clock over ambient temperatures. Issue 1 (19th March 2013)

• Record Type: Journal Article
• Authors: Gould, Peter D; Ugarte, Nicolas; Domijan, Mirela; Costa, Maria; Foreman, Julia; MacGregor, Dana; Rose, Ken; Griffiths, Jayne; Millar, Andrew J; Finkenstädt, Bärbel; Penfield, Steven; Rand, David A; Halliday, Karen J; Hall, Anthony J W
• Is Part Of: Molecular systems biology. Volume 9:Issue 1(2013)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2013-03-19
• Subjects: circadian rhythm -- genetic network -- mathematical model -- systems biology; Molecular biology -- Periodicals; Systems biology -- Periodicals; 572.8
• DOI: 10.1038/msb.2013.7
• Languages: English
• ISSNs: 1744-4292

Abstract

Abstract : Circadian clocks exhibit 'temperature compensation', meaning that they show only small changes in period over a broad temperature range. Several clock genes have been implicated in the temperature‐dependent control of period in Arabidopsis . We show that blue light is essential for this, suggesting that the effects of light and temperature interact or converge upon common targets in the circadian clock. Our data demonstrate that two cryptochrome photoreceptors differentially control circadian period and sustain rhythmicity across the physiological temperature range. In order to test the hypothesis that the targets of light regulation are sufficient to mediate temperature compensation, we constructed a temperature‐compensated clock model by adding passive temperature effects into only the light‐sensitive processes in the model. Remarkably, this model was not only capable of full temperature compensation and consistent with mRNA profiles across a temperature range, but also predicted the temperature‐dependent change in the level of LATE ELONGATED HYPOCOTYL, a key clock protein. Our analysis provides a systems‐level understanding of period control in the plant circadian oscillator. Abstract : Temperature compensation of the Arabidopsis circadian clock is shown to be mediated by the interaction of light and temperature at the level of the crytochrome photoreceptors. These findings reveal that light and temperature share common input mechanisms to the circadian network. Synopsis: Temperature compensation of the Arabidopsis circadian clock is shown to be mediated by the interaction of light and temperature at the level of the crytochrome photoreceptors. These findings reveal that light and temperature share common input mechanisms to the circadian network. We provide evidence that blue light signalling via the cryptochromes is important for the temperature‐dependent control of circadian period in plants. Light and temperature converge upon common targets in the circadian network. We have constructed a temperature‐compensated model of the plant circadian clock by adding a temperature effect to a subset of light‐sensitive processes. The model matches experimental data and predicted a temperature‐dependent change in the protein level of a key clock gene.