Defect in phorbol acetate-induced translocation of diacylglycerol kinase in erbB-transformed fibroblast cells

Abstract
We here show that tetradecanoyl phorbol acetate (TPA) and 1-oleoyl 2-acetyl glycerol (OAG) cause the translocation of diacylglycerol (DG) kinase from the cytosol to the membrane fractions in chick embryo fibroblast (CEF) cells. However, this translocation is not marked in erbB-transformed chick embryo fibroblast (GEV) cells. The activities of phosphatidylinositol (PI) and phosphatidylinositol 4-phosphate (PIP) kinases in membrane fractions are not altered by TPA treatment in either CEF or GEV cells. Such reduced translocation of DG kinase by TPA is also observed in src-transformed cells, but not in myc-transformed cells. These results suggest that the defect in DG kinase translocation may result in failure to suppress the overactivation of protein kinase C in erbB-2 and src-transformed cells, which may lead to cell growth and transformation