title: Exogenous phospholipase C permeabilizes mammalian cells to proteins.
abstract: Mammalian cells treated with low concentrations of phospholipase C become permeable to the protein toxin alpha-sarcin. A similar permeabilization is not induced upon treatment with other lipases such as phospholipase A2, sphingomyelinase, or cholesterol esterase. Concentrations of 10 micrograms/ml alpha-sarcin almost completely blocked translation in HeLa cells treated with 0.3 U/ml phospholipase C (PL-C) for 1 h. In contrast, 200 micrograms/ml of alpha-sarcin had no effect at all on protein synthesis in untreated cells. Other macromolecules such as horseradish peroxidase and luciferase also enter into cells if they are treated with phospholipase C. This permeabilization method is fully reversible. As soon as 5 min after PL-C removal, the cells become impermeable to alpha-sarcin. Other metabolites such as uridine nucleotides are partially released after PL-C incubation, whereas the content of 86Rb+ remains at control levels, probably because the Na+/K+ ATPase activity increases.
mesh_terms: D000818:Animals; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000378:metabolism; D002463:Cell Membrane Permeability / Q000187:drug effects*; D002794:Choline / Q000378:metabolism; D004722:Endoribonucleases; D005656:Fungal Proteins / Q000378:metabolism; D006367:HeLa Cells; D019301:Oleic Acid; D009829:Oleic Acids / Q000378:metabolism; D010042:Ouabain / Q000494:pharmacology; D010741:Phospholipases A / Q000494:pharmacology; D054467:Phospholipases A2; D011506:Proteins / Q000378:metabolism*; D012414:Rubidium Radioisotopes / Q000378:metabolism; D013108:Sphingomyelin Phosphodiesterase / Q000494:pharmacology; D002787:Sterol Esterase / Q000494:pharmacology; D014316:Tritium; D010738:Type C Phospholipases / Q000494:pharmacology*; D014529:Uridine / Q000378:metabolism; D014709:Vero Cells
chemical_list: D001095:Arachidonic Acids; D005656:Fungal Proteins; D009829:Oleic Acids; D011506:Proteins; D012414:Rubidium Radioisotopes; D014316:Tritium; C014801:alpha-sarcin; D016718:Arachidonic Acid; D019301:Oleic Acid; D010042:Ouabain; D004722:Endoribonucleases; D002787:Sterol Esterase; D010741:Phospholipases A; D054467:Phospholipases A2; D010738:Type C Phospholipases; D013108:Sphingomyelin Phosphodiesterase; D002794:Choline; D014529:Uridine