Calcium signaling in Xenopus oocyte.

Knowledge about calcium signaling had increased thanks to the development and manipulation of various cell models. Among all of these prototypes, Xenopus laevis oocyte appears to be one of the most relevant. The understanding of the role of calcium during oocyte oogenesis, maturation and fertilization is facilitated by the big size of the cell but also by using imaging and electrophysiological approaches. So, this chapter presents how recordings of calcium-activated chloride channels and Store-Operated Calcium Channels activities lead to demonstrate the implication of the MPF in the uncoupling between intracellular calcium releasing and capacitative calcium entry. Moreover, it will help us to understand the several reorganizations happening consequently to the pH variations of maturation or just at the moment of fertilization.