title: Stabilization of the maturation promoting factor (MPF) from Xenopus laevis oocytes. Protection against calcium ions.
abstract: Maturation promoting factor (MPF) activity was recovered from progesterone-matured Xenopus oocytes cytosol, fractionated by polyethylene glycol-20,000 or ethanolic precipitation. An improved stabilization of the biological activity was obtained by adding adenosine 5'-O-(3-thiotriphosphate) (ATP-gamma-S) (50 microM) to the preparation buffers. Neither Ca2+ ions nor calmodulin inhibit the partially purified MPF.
mesh_terms: D000255:Adenosine Triphosphate / Q000031:analogs & derivatives / Q000494:pharmacology; D000818:Animals; D002021:Buffers; D002118:Calcium / Q000494:pharmacology; D005260:Female; D006133:Growth Substances / Q000302:isolation & purification*; D016200:Maturation-Promoting Factor; D008540:Meiosis / Q000187:drug effects; D009865:Oocytes / Q000032:analysis*; D011092:Polyethylene Glycols; D011480:Protease Inhibitors; D011489:Protein Denaturation / Q000187:drug effects; D014982:Xenopus laevis
chemical_list: D002021:Buffers; D006133:Growth Substances; D011480:Protease Inhibitors; D011092:Polyethylene Glycols; D000255:Adenosine Triphosphate; D016200:Maturation-Promoting Factor; D002118:Calcium