ITPR2: Proteins and Enzymes

Inositol 1,4,5-triphosphate (IP3) receptors are a form of ligand-gated ion channels that are activated by cytosolic Ca2+ and IP3. They are localized to intracellular membranes, such as the endoplasmic reticulum, and mediate the mobilization of intracellular Ca2+ stores. IP3 receptors play an important role in intracellular Ca2+ signaling in a variety of cell types. There are three IP3 receptor subtypes; IP3R1, IP3R2 and IP3R3, which exist as homo- and heterotetramers. All subtypes are closely associated with calmodulin and FK506-binding protein and are modulated through phosphorylation by PKA, PKC, PKG and CaMKII.