[Basis for the calcium specificity in the plant response to extracellular stimulation]. / Les supports de la spécificité calcique dans la réponse des plantes aux stimuli extracellulaires.

The Ca2+ cation is fully recognized as an important intracellular second messenger coupling a wide range of extracellular stimuli to characteristic responses in plant cells. Such a pleiotropic effect raises questions regarding the mechanisms by which the signalling pathways, all of then involving an increase in intracellular calcium concentration, can be specific to a given stimulus. Here, we present recent results which shed light into different concepts which may explain the response specificity in signalling processes, such as "the cross-talk between signalling pathways", "the Ca2+ signatures" and "the compartmentation of Ca(2+)-signalling".