In vivo progesterone regulation of protein phosphatase activity in Xenopus oocytes.
Exogenous beta casein, previously phosphorylated in vitro by protein kinase A and casein kinase II, was microinjected into Xenopus oocytes to monitor in vivo protein phosphatase activities. Phosphatase activities were 1.6 and 3.4 fmol/min/oocyte, respectively, for beta casein phosphorylated by casein kinase II and beta casein phosphorylated by protein kinase A. Progesterone induced an early decrease (35% after 10 min) in phosphatase activity restricted to the protein kinase A sites of beta casein.
Cormier
P
P
Physiologie de la Reproduction, CNRS UA 555, INRA, Paris, France.
Mulner-Lorillon
O
O
Belle
R
R
D000818:Animals; D002364:Caseins / Q000008:administration & dosage / Q000378:metabolism; D005260:Female; D007700:Kinetics; D008845:Microinjections; D009865:Oocytes / Q000187:drug effects / Q000201:enzymology*; D010749:Phosphoprotein Phosphatases / Q000378:metabolism*; D011374:Progesterone / Q000494:pharmacology*; D014982:Xenopus laevis
D002364:Caseins; D011374:Progesterone; D010749:Phosphoprotein Phosphatases