In SYNC: The Ins and Outs of Circadian Oscillations in Calcium
Takato Imaizumi1*,
Julian I. Schroeder2, and
Steve A. Kay1*
1Department of Biochemistry, Scripps Research Institute, La Jolla, CA 92037, USA.
2Division of Biological Sciences, Cell and Developmental Biology Section, University of California, San Diego, La Jolla, CA 92093, USA.
Abstract:
Many stimuli induce short-term increases in the cytosolic concentration of free calcium ions ([Ca2+]i) that encode signaling information about diverse physiological and developmental events. Slow cytosolic Ca2+ oscillations that span an entire day have also been discovered in both plants and animals; it is thought that these daily Ca2+ oscillations may encode circadian clock signaling information. A recent study focusing on the characterization of the extracellular Ca2+-sensing receptor (CAS) has provided insight into the molecular mechanisms by which the daily Ca2+ oscillation in plants is generated. We summarize the major findings regarding daily oscillations of cytosolic Ca2+ concentrations in plants and animals, and discuss hypothetical biological roles for the circadian clock–regulated physiology in plants.
*Corresponding authors. E-mail, takato{at}scripps.edu; stevek{at}scripps.edu
