Signal transduction in EJ‐H‐ras‐transformed cells: De novo synthesis of diacylglycerol and subversion of agonist‐stimulated inositol lipid metabolism

FEBS Letters

Basi, Gabriele¹  Magnelli, Lucia¹  Pasquali, Franca¹  Ruggiero, Marco¹  Chiarugi, Vincenzo P.¹ 

[1] Laboratory of Molecular Biology, Institute of General Pathology, University of Firenze, Viale Morgagni 50, 50134 Firenze, Italy

关键词: Oncogene;    ras;    Inositol lipid;    Diacylglycerol;    Signal transduction;   

DOI  :  10.1016/0014-5793(89)80904-4

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

We examined the level of 1,2-diacylglycerol and inositol phosphates in normal and EJ-H-ras-transformed BALB/3T3 fibroblasts by prelabelling the cells with [³H]glycerol, [³H]inositol, [^14C]glucose, [¹⁴C]arachidonic acid, and [¹⁴]palmitic acid. Steady-state level of diacylglycerol was increased in ras-transformed cells prelabelled with radioactive glycerol, glucose and palmitic acid. Steady-state level of inositol phosphates, however, was the same in control and transformed cells. Diacylglycerol labelling by [¹⁴C]arachidonic acid was the same in control and transformed cells. Insulin dramatically increased diacylglycerol labelling by [¹⁴C]glucose in normal cells, wheras it did not affect ras-transformed fibroblasts. Neurotransmitter-induced inositol lipid turnover was greatly enhanced in ras-transformed cells; conversely, platelet-derived growth factor and thrombin-stimulated normal cells to a greater extent than transformed fibroblasts. Taken together these results suggest that ras transformation may induce multifarious effects on signal transduction: it may cause de novo synthesis of diacylglycerol and subversion of neurotransmitter and growth factor receptor coupling to inositol lipid metabolism.

【 授权许可】

Unknown