An okadaic acid-sensitive phosphatase negatively controls the cyclin degradation pathway in amphibian eggs.
Inhibition of okadaic acid-sensitive phosphatases released the cyclin degradation pathway from its inhibited state in extracts prepared from unfertilized Xenopus eggs arrested at the second meiotic metaphase. It also switched on cyclin protease activity in a permanent fashion in interphase extracts prepared from activated eggs. Even after cdc2 kinase inactivation, microinjection of okadaic acid-treated interphase extracts pushed G2-arrested recipient oocytes into the M phase, suggesting that the phosphatase inhibitor stabilizes the activity of an unidentified factor which shares in common with cdc2 kinase the maturation-promoting factor activity.
Lorca
T
T
CNRS, Montpellier, France.
Fesquet
D
D
Zindy
F
F
Le Bouffant
F
F
Cerruti
M
M
Brechot
C
C
Devauchelle
G
G
Dorée
M
M
D000818:Animals; D016203:CDC2 Protein Kinase / Q000378:metabolism; D002453:Cell Cycle / Q000187:drug effects; D016213:Cyclins / Q000378:metabolism*; D004988:Ethers, Cyclic / Q000494:pharmacology*; D005260:Female; D006706:Homeostasis; D007476:Ionophores / Q000494:pharmacology; D007700:Kinetics; D008540:Meiosis / Q000187:drug effects; D008677:Metaphase; D008954:Models, Biological; D019319:Okadaic Acid; D009865:Oocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D010749:Phosphoprotein Phosphatases / Q000378:metabolism*; D014981:Xenopus
D016213:Cyclins; D004988:Ethers, Cyclic; D007476:Ionophores; D019319:Okadaic Acid; D016203:CDC2 Protein Kinase; C067024:okadaic acid-sensitive phosphatase; D010749:Phosphoprotein Phosphatases