title: Specific high affinity cell membrane receptors for biologically active phorbol and ingenol esters.
abstract: A variety of normal and transformed avian and mammalian cells and tissues contain high affinity specific receptors on their membranes which interact with biologically active phorbol and ingenol esters in a reversible and saturable manner. The binding of labelled phorbol-12,13-dibutyrate (PDBu) to live or glutaraldehyde-fixed cells is dose-, time- and temperature-dependent. Those phorbol or ingenol esters which stimulate cell growth in culture and have tumour-promoting activity in vivo inhibit the binding of labelled PDBu, while the biologically inactive derivatives fail to do so. Other non-diterpene tumour-promoting agents, epidermal growth factor (EGF), retinoids and prostaglandins do not compete for the binding of labelled PDBu to its specific membrane receptors.
mesh_terms: D000818:Animals; D001667:Binding, Competitive; D029742:Caenorhabditis elegans Proteins; D002352:Carrier Proteins; D002462:Cell Membrane / Q000378:metabolism*; D002478:Cells, Cultured; D004224:Diterpenes / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D010703:Phorbol Esters / Q000378:metabolism*; D010704:Phorbols / Q000378:metabolism*; D011493:Protein Kinase C; D011955:Receptors, Drug / Q000378:metabolism*; D013329:Structure-Activity Relationship; D013696:Temperature
chemical_list: D029742:Caenorhabditis elegans Proteins; D002352:Carrier Proteins; D004224:Diterpenes; D010703:Phorbol Esters; D010704:Phorbols; D011955:Receptors, Drug; C027777:ingenol ester receptor; C083141:phorbol ester binding protein; C027776:phorbol ester receptor; C027280:ingenol-3,5,20-triacetate; D011493:Protein Kinase C; C008125:ingenol