title: Enzymatic synthesis and hydrolysis of [32P]phosphatidylinositol phosphate.
abstract: Phosphatidylinositol kinase activity in plasma membrane preparations of mouse liver was found to be comparable to that in A431 cells and higher than that in three human tumor xenografts. This activity was exploited in preparing 32P-labeled phosphatidylinositol phosphate of high specific radioactivity in which approximately 4% of the radioactivity of the substrate, [gamma-32P]ATP, was incorporated into the lipid. The subcellular distribution of phosphatidylinositol phosphate phosphatase in a human astrocytoma xenograft was determined using [32P]phosphatidylinositol phosphate as a substrate. The highest phosphatase activity was found in the plasma membranes.
authors.forename: A F
authors.initials: AF
authors.lastname: Knowles
authors.forename: C M
authors.initials: CM
authors.lastname: Lawrence
mesh_terms: D019870:1-Phosphatidylinositol 4-Kinase; D000818:Animals; D001254:Astrocytoma / Q000201:enzymology; D018288:Carcinoma, Small Cell / Q000201:enzymology; D002460:Cell Line; D002462:Cell Membrane / Q000201:enzymology; D002855:Chromatography, Thin Layer; D006801:Humans; D006868:Hydrolysis; D008099:Liver / Q000201:enzymology; D008114:Liver Neoplasms, Experimental / Q000201:enzymology; D051379:Mice; D018129:Phosphatidylinositol Phosphates; D010716:Phosphatidylinositols / Q000378:metabolism*; D010744:Phosphoric Monoester Hydrolases / Q000378:metabolism; D010770:Phosphotransferases / Q000378:metabolism
chemical_list: D018129:Phosphatidylinositol Phosphates; D010716:Phosphatidylinositols; C037178:phosphatidylinositol 4-phosphate; D010770:Phosphotransferases; D019870:1-Phosphatidylinositol 4-Kinase; D010744:Phosphoric Monoester Hydrolases; C053153:phosphatidylinositol-3,4-bisphosphate 4-phosphatase