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Updated: Jul 9, 2026
07:42
Rapid Analysis of Circadian Phenotypes in Arabidopsis Protoplasts Transfected with a Luminescent Clock Reporter
Published on: September 17, 2016
The Arabidopsis circadian clock incorporates a cADPR-based feedback loop
Antony N Dodd1, Michael J Gardner, Carlos T Hotta
1Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK.
Science (New York, N.Y.)
|December 18, 2007
Summary
The plant circadian clock uses cyclic adenosine diphosphate ribose (cADPR) to regulate its transcriptional feedback loops. This signaling molecule drives calcium oscillations, forming a novel feedback mechanism within the clock.
Area of Science:
- Plant biology
- Chronobiology
- Molecular signaling
Background:
- Circadian clocks in plants and animals rely on transcriptional feedback loops.
- The role of cytosolic signaling molecules in plant circadian rhythms is not fully understood.
Purpose of the Study:
- To investigate the involvement of cyclic adenosine diphosphate ribose (cADPR) in the plant circadian clock.
- To determine if cADPR modulates transcriptional feedback loops and influences calcium oscillations.
Main Methods:
- Utilized antagonists of cADPR signaling.
- Manipulated cADPR synthesis pathways.
- Employed mathematical simulations to model cADPR-circadian clock interactions.
Main Results:
- Demonstrated that cADPR modulates the transcriptional feedback loops of the circadian oscillator.
- Showed that cADPR drives circadian oscillations in cytosolic calcium (Ca2+) release.
- Evidence suggests cADPR forms an integral feedback loop within the plant circadian clock.
Conclusions:
- cADPR is a key component of the plant circadian clock.
- cADPR signaling influences both transcriptional regulation and calcium dynamics in circadian rhythms.
- The study reveals a novel feedback mechanism involving cADPR in plant timekeeping.
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