Calcium signaling in plant cell organelles delimited by a double membrane.
Increases in the concentration of free calcium in the cytosol are one of the general events that relay an external stimulus to the internal cellular machinery and allow eukaryotic organisms, including plants, to mount a specific biological response. Different lines of evidence have shown that other intracellular organelles contribute to the regulation of free calcium homeostasis in the cytosol. The vacuoles, the endoplasmic reticulum and the cell wall constitute storage compartments for mobilizable calcium. In contrast, the role of organelles surrounded by a double membrane (e.g. mitochondria, chloroplasts and nuclei) is more complex. Here, we review experimental data showing that these organelles harbor calcium-dependent biological processes. Mitochondria, chloroplasts as well as nuclei are equipped to generate calcium signal on their own. Changes in free calcium in a given organelle may also favor the relocalization of proteins and regulatory components and therefore have a profound influence on the integrated functioning of the cell. Studying, in time and space, the dynamics of different components of calcium signaling pathway will certainly give clues to understand the extraordinary flexibility of plants to respond to stimuli and mount adaptive responses. The availability of technical and biological resources should allow breaking new grounds by unveiling the contribution of signaling networks in integrative plant biology.
Xiong
Tou-Cheu
TC
UMR CNRS/Université Paul Sabatier 5546, Surfaces Cellulaires et Signalisation chez les Végétaux, Pôle de Biotechnologie Végétale, 24 chemin de Borde Rouge, Auzeville BP42617, 31326 Castanet-Tolosan, France.
Bourque
Stéphane
S
Lecourieux
David
D
Amelot
Nicolas
N
Grat
Sabine
S
Brière
Christian
C
Mazars
Christian
C
Pugin
Alain
A
Ranjeva
Raoul
R
D002118:Calcium / Q000378:metabolism*; D020013:Calcium Signaling; D002462:Cell Membrane / Q000378:metabolism*; D003600:Cytosol / Q000378:metabolism; D015388:Organelles / Q000378:metabolism* / Q000648:ultrastructure; D010944:Plants / Q000378:metabolism* / Q000648:ultrastructure
D002118:Calcium