title: The nuclear-associated endoplasmic reticulum is an early target for the action of the tumor promoter 12-O-tetradecanoyl phorbol-13-acetate in C3H/10T1/2 fibroblasts.
abstract: 12-O-Tetradecanoyl-phorbol-13-acetate (TPA) had a dual effect on the cellular membranes of C3H/10T1/2 cells in that it caused both a stimulation of [3H]choline incorporation and an enhancement of the solubilization of choline from prelabelled cells. Subfractionation studies showed that the release of [3H]choline occurred almost exclusively from nuclear-associated endoplasmic reticulum. The release was dependent on the presence of Mg2+ and Ca2+, indicating an enzyme-mediated reaction. In vivo, TPA stimulated the incorporation of [3H]choline into all subcellular fractions. The data indicate that the nuclear-associated endoplasmic reticulum represents an early target for TPA action.
mesh_terms: D000818:Animals; D002467:Cell Nucleus / Q000187:drug effects*; D002471:Cell Transformation, Neoplastic / Q000187:drug effects; D002478:Cells, Cultured; D002794:Choline / Q000378:metabolism; D004721:Endoplasmic Reticulum / Q000187:drug effects*; D007425:Intracellular Membranes / Q000378:metabolism; D008563:Membrane Lipids / Q000378:metabolism; D051379:Mice; D010704:Phorbols / Q000494:pharmacology*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
chemical_list: D008563:Membrane Lipids; D010704:Phorbols; D002794:Choline; D013755:Tetradecanoylphorbol Acetate