Solubilization, purification, and reconstitution of a phorbol ester receptor from the particulate protein fraction of mouse brain.

The protein that specifically binds 12-O-[3H]tetradecanoyl-phorbol-13-acetate was solubilized from mouse brain particulate protein with detergents and purified to apparent homogeneity by chromatograph on diethylaminoethyl-cellulose, hydroxylapatite, phenyl agarose, and gel filtration. The purified binding activity consisted of a single polypeptide of apparent molecular weight of 70,000. The isolated receptor protein required reconstitution with phospholipid and cations for binding. The solubilization, isolation, and reconstitution of the receptor did not alter its relative affinity for several different phorbol esters. The isolation of the receptor will aid the determination of both its biological function and its extent of involvement in tumor promotion and cellular physiology.