The plant clock shows its metal: circadian regulation of cytosolic free Ca(2+).
Signal transduction events that lead to circadian control of physiology are poorly understood. Signalling elements that could transmit time information include transcription factors, reversible phosphorylation, and changes in the concentration of cytosolic free calcium ([Ca(2+)](cyt)). [Ca(2+)](cyt) oscillates with a circadian rhythm in Arabidopsis and Nicotiana, but does not have a defined role in circadian signalling. [Ca(2+)](cyt) oscillations with shorter periods encode specific signals in several cell types, therefore circadian [Ca(2+)](cyt) oscillations provide a potential mechanism for signalling time information. Cell types such as stomatal guard cells and legume pulvini represent attractive model systems for dissecting circadian Ca(2+) signalling.
Dodd
Antony N
AN
Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge, UK CB2 3EA. antony.dodd@plantsci.cam.ac.uk
Love
John
J
Webb
Alex A R
AA
D002118:Calcium / Q000378:metabolism / Q000502:physiology*; D002940:Circadian Rhythm / Q000502:physiology*; D003600:Cytosol / Q000378:metabolism*; D018525:Germination / Q000502:physiology; D008027:Light; D018521:Plant Physiological Phenomena; D010944:Plants / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology*; D014158:Transcription, Genetic
D002118:Calcium