Coupling diurnal cytosolic Ca2+ oscillations to the CAS-IP3 pathway in Arabidopsis.
Various signaling pathways rely on changes in cytosolic calcium ion concentration ([Ca2+]i). In plants, resting [Ca2+]i oscillates diurnally. We show that in Arabidopsis thaliana, [Ca2+]i oscillations are synchronized to extracellular Ca2+ concentration ([Ca2+]o) oscillations largely through the Ca2+-sensing receptor CAS. CAS regulates concentrations of inositol 1,4,5-trisphosphate (IP3), which in turn directs release of Ca2+ from internal stores. The oscillating amplitudes of [Ca2+]o and [Ca2+]i are controlled by soil Ca2+ concentrations and transpiration rates. The phase and period of oscillations are likely determined by stomatal conductance. Thus, the internal concentration of Ca2+ in plant cells is constantly being actively revised.
Tang
Ru-Hang
RH
Department of Biology, Duke University, Durham, NC 27708, USA.
Han
Shengcheng
S
Zheng
Hailei
H
Cook
Charles W
CW
Choi
Christopher S
CS
Woerner
Todd E
TE
Jackson
Robert B
RB
Pei
Zhen-Ming
ZM
D000331:Aequorin / Q000378:metabolism; D017360:Arabidopsis / Q000166:cytology / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism*; D020013:Calcium Signaling; D002940:Circadian Rhythm; D003001:Cloning, Molecular; D006801:Humans; D015544:Inositol 1,4,5-Trisphosphate / Q000378:metabolism*; D017136:Ion Transport; D049449:Luminescence; D018520:Plant Shoots / Q000378:metabolism; D018526:Plant Transpiration; D044169:Receptors, Calcium-Sensing / Q000235:genetics / Q000378:metabolism*; D012987:Soil / Q000032:analysis
D029681:Arabidopsis Proteins; D044169:Receptors, Calcium-Sensing; D012987:Soil; D000331:Aequorin; D015544:Inositol 1,4,5-Trisphosphate; D002118:Calcium