Inactivation of protein kinase A is not required for c-mos translation during meiotic maturation of Xenopus oocytes.
It has been shown previously that protein kinase A (PKA) maintains Xenopus oocytes arrested at G2, at least in part by preventing c-mos translation, but how PKA controls c-mos translation is not known. Using microinjection of recombinant c-mos, which still activates MAP kinase in the presence of active PKA, we have found that PKA does not exert any effect on translation of endogenous c-mos if MAP kinase is first activated. Even though they accumulate c-mos and contain MAP kinase activity as high as control oocytes, oocytes do not exit G2 in the presence of active PKA. These results are discussed in connection with recent findings on regulation of c-raf activity.
Faure
S
S
Centre de Recherches de Biochimie Macromoléculaire, CNRS, Montpellier, France.
Morin
N
N
Dorée
M
M
D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology; D000818:Animals; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism*; D004789:Enzyme Activation; D005260:Female; D016195:G2 Phase; D016200:Maturation-Promoting Factor / Q000378:metabolism; D008540:Meiosis; D008845:Microinjections; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D009865:Oocytes / Q000187:drug effects / Q000502:physiology*; D014176:Protein Biosynthesis; D011494:Protein Kinases / Q000187:drug effects / Q000378:metabolism; D017231:Proto-Oncogene Proteins c-mos / Q000235:genetics* / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D014981:Xenopus
D011994:Recombinant Proteins; D011494:Protein Kinases; C102333:histone H1 kinase; D017231:Proto-Oncogene Proteins c-mos; D017868:Cyclic AMP-Dependent Protein Kinases; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D016200:Maturation-Promoting Factor; D019950:Mitogen-Activated Protein Kinase 1; D015056:1-Methyl-3-isobutylxanthine