Ins(1,4,5)P3 is a second messenger produced in cells by PLC mediated hydrolysis of phosphatidyl inositol-4,5-biphosphate.{2429,5714} It binds to one of several Ins(1,4,5)P3 receptors, each containing a calcium channel domain. Binding of Ins(1,4,5)P3 to the receptor results in opening of the calcium channels and an increase in intracellular calcium.{5714,4096}