A tumor promoter enhances the phosphorylation of polyphosphoinositides while decreasing phosphatidylinositol labelling in lymphocytes.
12-O-Tetradecanoyl-phorbol-13-acetate, a comitogen for lymphocytes, suppresses the concanavalin A-induced accumulation of 3 2P-phosphatidyl-inositol, in mouse spleen lymphocytes incubated with 3 2P-orthophosphate. The comitogenic tumor promoter does not affect the rate of de novo synthesis of phosphatidylinositol, as measured by [3H]-glycerol incorporation. Mitogen stimulates the incorporation of [3 2P]-phosphate into phosphatidylinositol, phosphatidylinositol-4-phosphate and phosphatidylinositol-4,5-bisphosphate, but the tumor promoter suppresses only the increased labelling of the phosphatidylinositol, while it enhances phosphorylation of the polyphosphoinositides.
Boon
A M
AM
Beresford
B J
BJ
Mellors
A
A
D000818:Animals; D003208:Concanavalin A / Q000494:pharmacology; D019852:Diacylglycerol Kinase; D005260:Female; D005990:Glycerol / Q000378:metabolism; D066298:In Vitro Techniques; D008214:Lymphocytes / Q000187:drug effects* / Q000378:metabolism; D051379:Mice; D010704:Phorbols / Q000494:pharmacology*; D018129:Phosphatidylinositol Phosphates; D010716:Phosphatidylinositols / Q000378:metabolism*; D010766:Phosphorylation; D010770:Phosphotransferases / Q000378:metabolism; D013154:Spleen / Q000187:drug effects; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
D010704:Phorbols; D018129:Phosphatidylinositol Phosphates; D010716:Phosphatidylinositols; D003208:Concanavalin A; D010770:Phosphotransferases; D019852:Diacylglycerol Kinase; D013755:Tetradecanoylphorbol Acetate; D005990:Glycerol