Cyclic AMP (cAMP) is an important signal carrier necessary for the proper biological response of cells to hormones, neurotransmitters, and other extracellular signals Forskolin is a naturally occurring diterpene that is produced by the Indian Coleus plant (C. forskohlii). It directly activates adenylyl cyclase through its catalytic subunit and is commonly used to raise levels of cAMP in a wide variety of intact cells and tissue preparations. Forskolin binds to adenylyl cyclase in membranes from stably transfected Sf9 cells expressing type 1 adenylyl cyclase with an IC50 value of 41 nM and demonstrates an EC50 value of 0.5 μM in an activation assay assessing formation of cAMP from ATP. Forskolin also interacts with glucose transporters and certain ion channels and has been used for examining adenylyl cyclase expression, regulation, and G protein signaling.
