Click here to close
Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly.
We suggest using a current version of Chrome,
FireFox, or Safari.
???displayArticle.abstract???
Xenopus oocytes are arrested in meiotic prophase I. Progesterone induces the resumption of meiotic maturation, which requires continuous protein synthesis to bring about Cdc2 activation. The identification of the newly synthesized proteins has long been a goal. Two plausible candidates have received extensive study. The synthesis of cyclin B and of c-Mos, a kinase that activates the mitogen-activated protein kinase pathway in oocytes, is clearly upregulated by translational control in response to progesterone. Recent studies suggest that ablation of either c-Mos or cyclin B synthesis by antisense oligonucleotides does not block meiotic maturation. Here, however, we show that when both pathways are simultaneously inhibited, progesterone no longer triggers maturation; adding back either c-Mos or cyclin B restores meiotic maturation. We conclude that the specific synthesis of either B-type cyclins or c-Mos, induced by progesterone, is required to induce meiotic maturation. The two pathways seem to be functionally redundant.
Castro,
Cyclin B/cdc2 induces c-Mos stability by direct phosphorylation in Xenopus oocytes.
2001, Pubmed,
Xenbase
Castro,
Cyclin B/cdc2 induces c-Mos stability by direct phosphorylation in Xenopus oocytes.
2001,
Pubmed
,
Xenbase
De Smedt,
Thr-161 phosphorylation of monomeric Cdc2. Regulation by protein phosphatase 2C in Xenopus oocytes.
2002,
Pubmed
,
Xenbase
Dupré,
Mos is not required for the initiation of meiotic maturation in Xenopus oocytes.
2002,
Pubmed
,
Xenbase
Eyers,
Regulation of the G(2)/M transition in Xenopus oocytes by the cAMP-dependent protein kinase.
2005,
Pubmed
,
Xenbase
Ferby,
A novel p34(cdc2)-binding and activating protein that is necessary and sufficient to trigger G(2)/M progression in Xenopus oocytes.
1999,
Pubmed
,
Xenbase
Frank-Vaillant,
Two distinct mechanisms control the accumulation of cyclin B1 and Mos in Xenopus oocytes in response to progesterone.
1999,
Pubmed
,
Xenbase
Gross,
A constitutively active form of the protein kinase p90Rsk1 is sufficient to trigger the G2/M transition in Xenopus oocytes.
2001,
Pubmed
,
Xenbase
Gross,
The critical role of the MAP kinase pathway in meiosis II in Xenopus oocytes is mediated by p90(Rsk).
2000,
Pubmed
,
Xenbase
Haccard,
Induction of Xenopus oocyte meiotic maturation by MAP kinase.
1995,
Pubmed
,
Xenbase
Hochegger,
New B-type cyclin synthesis is required between meiosis I and II during Xenopus oocyte maturation.
2001,
Pubmed
,
Xenbase
Huang,
Biochemical and biological analysis of Mek1 phosphorylation site mutants.
1995,
Pubmed
,
Xenbase
Jessus,
Tyrosine phosphorylation of p34cdc2 and p42 during meiotic maturation of Xenopus oocyte. Antagonistic action of okadaic acid and 6-DMAP.
1991,
Pubmed
,
Xenbase
Karaiskou,
From progesterone to active Cdc2 in Xenopus oocytes: a puzzling signalling pathway.
2001,
Pubmed
,
Xenbase
Karaiskou,
Polo-like kinase confers MPF autoamplification competence to growing Xenopus oocytes.
2004,
Pubmed
,
Xenbase
Karaïskou,
Phosphatase 2A and polo kinase, two antagonistic regulators of cdc25 activation and MPF auto-amplification.
1999,
Pubmed
,
Xenbase
Lenormand,
Speedy: a novel cell cycle regulator of the G2/M transition.
1999,
Pubmed
,
Xenbase
Palmer,
A link between MAP kinase and p34(cdc2)/cyclin B during oocyte maturation: p90(rsk) phosphorylates and inactivates the p34(cdc2) inhibitory kinase Myt1.
1998,
Pubmed
,
Xenbase
Peter,
A new role for Mos in Xenopus oocyte maturation: targeting Myt1 independently of MAPK.
2002,
Pubmed
,
Xenbase
Posada,
Mos stimulates MAP kinase in Xenopus oocytes and activates a MAP kinase kinase in vitro.
1993,
Pubmed
,
Xenbase
Sagata,
Function of c-mos proto-oncogene product in meiotic maturation in Xenopus oocytes.
1988,
Pubmed
,
Xenbase
Uto,
Chk1, but not Chk2, inhibits Cdc25 phosphatases by a novel common mechanism.
2004,
Pubmed
,
Xenbase
Wasserman,
Effects of cyclohexamide on a cytoplasmic factor initiating meiotic naturation in Xenopus oocytes.
1975,
Pubmed
,
Xenbase
