title: Translocation of protein kinase C in human leukemia cells susceptible or resistant to differentiation induced by phorbol 12-myristate 13-acetate.
abstract: We investigated the possible relationship between the susceptibility of cells to differentiation induced by phorbol 12-myristate 13-acetate (PMA) and the subcellular translocation of calcium- and phospholipid-dependent protein kinase (protein kinase C) activity from the cytosol to the membrane. These two events were analyzed in a number of human leukemia cell lines, including four cell variants of the promyelocytic cell line HL-60 that exhibit different degrees of susceptibility to PMA-induced differentiation. The phenotype of the differentiated cells was characterized by increased reactivity with monoclonal antibodies against maturation-specific cell surface antigens, increased nonspecific esterase activity, and acquisition of morphological cell maturation. Analysis of the subcellular distribution of protein kinase C activity in each of these cell types revealed that 90% of the kinase activity was present in the cytosolic fraction, with the remaining activity in the membrane fraction. Treatment of the differentiation-susceptible cells with 160 nM PMA resulted, within 5 min after treatment, in a greater than 60% decrease in protein kinase C activity in the cytosolic fraction and a greater than 1500% increase in the activity in the membrane fraction. No such subcellular redistribution of protein kinase C activity was found after treatment of the differentiation-resistant cells. On the basis of these findings, we suggest that the process of subcellular translocation of protein kinase C activity, initiated after the binding of PMA to this kinase, is required for the induction of cell differentiation by this phorbol diester.
authors.forename: Y
authors.initials: Y
authors.lastname: Homma
authors.forename: C B
authors.initials: CB
authors.lastname: Henning-Chubb
authors.forename: E
authors.initials: E
authors.lastname: Huberman
mesh_terms: D002451:Cell Compartmentation; D002454:Cell Differentiation / Q000187:drug effects; D002460:Cell Line; D002462:Cell Membrane / Q000201:enzymology; D003600:Cytosol / Q000201:enzymology; D006801:Humans; D007942:Leukemia, Experimental / Q000201:enzymology / Q000473:pathology*; D011493:Protein Kinase C / Q000378:metabolism*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
chemical_list: D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate