Xenopus oocyte maturation: new lessons from a good egg

Bioessays. 1999 Oct;21(10):833-42. doi: 10.1002/(SICI)1521-1878(199910)21:10<833::AID-BIES5>3.0.CO;2-P.


Fully grown Xenopus oocytes can remain in their immature state essentially indefinitely, or, in response to the steroid hormone progesterone, can be induced to develop into fertilizable eggs. This process is termed oocyte maturation. Oocyte maturation is initiated by a novel plasma membrane steroid hormone receptor. Progesterone brings about inhibition of adenylate cyclase and activation of the Mos/MEK1/p42 MAP kinase cascade, which ultimately brings about the activation of the universal M phase trigger Cdc2/cyclin B. Oocyte maturation provides an interesting example of how signaling cascades entrain the cell cycle clock to environmental changes.

Publication types

  • Research Support, U.S. Gov't, P.H.S.
  • Review

MeSH terms

  • Animals
  • CDC2 Protein Kinase / metabolism
  • Cyclic AMP-Dependent Protein Kinases / metabolism
  • Cyclins / metabolism
  • Female
  • Mitogen-Activated Protein Kinases / metabolism
  • Oocytes / growth & development*
  • Oocytes / metabolism
  • Oogenesis
  • Phosphatidylinositol 3-Kinases / metabolism
  • Phosphorylation
  • Receptors, Progesterone / metabolism
  • Signal Transduction
  • Xenopus / growth & development*
  • Xenopus / metabolism


  • Cyclins
  • Receptors, Progesterone
  • Phosphatidylinositol 3-Kinases
  • Cyclic AMP-Dependent Protein Kinases
  • CDC2 Protein Kinase
  • Mitogen-Activated Protein Kinases