Mechanisms that turn-off intracellular calcium release channels

Calcium release from intracellular stores is a common phenomenon in cells. Calcium release is mediated by two classes of Ca2+ release channels, the ryanodine receptors (RyRs) and the inositol trisphosphate receptors (IP3Rs). There are three types of RyR and three types of IP3Rs. Different cells have different complements of RyR and IP3Rs. In most cases, it is clear what turns-on these channels. It is often unclear what turns them off. It appears that a composite of factors and/or processes may act in synergy to regulate these channels and terminate local intracellular Ca release events. This review details some of the potential negative control mechanisms that may govern individual RyR and IP3R channel activity.