Inositol triphosphate
Inositol triphosphate (abbreviated InsP
3 or IP
3, also called triphosphoinositol), together with
diacylglycerol, is a
second messenger molecule used in
signal transduction in biological cells. It is made by hydrolysis of phosphatidyl inositol, a
phospholipid that is located in the
plasma membrane, by
phospholipase C.
Its main functions are to mobilize Ca2+ from storage organelles and to regulate cell proliferation and other cellular reactions. For example, in Drosophila, InsP3 is used for intracellular transduction of light recognition in eye cells.