ABSTRACT
IP3, as described above, is derived from hydrolysis of PIP,. It is a watersoluble molecule and mobilizes calcium from intracellular stores in the endoplasmic reticulum where the cation is bound to proteins which exhibit lowaffinity, high-capacity binding sites. IP, binds to specific glycoprotein receptors in the endoplasmic reticulum, opening calcium gates to allow a rise in cytosolic calcium concentration which, in turn, activates calcium-dependent processes.
