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Xenopus laevis as a Model to Identify Translation Impairment
Published on: September 27, 2015
From progesterone to active Cdc2 in Xenopus oocytes: a puzzling signalling pathway
A Karaiskou1, A Dupré, O Haccard
1Laboratoire de Biologie du Développement, UMR-CNRS 7622, Université Pierre et Marie Curie, Paris, France.
Biology of the Cell
|December 4, 2001
Summary
Progesterone triggers amphibian oocyte maturation by regulating protein kinase A (PKA) and c-Mos synthesis. This study proposes a model to clarify the role of the Mos/MAP kinase pathway in maturation-promoting factor (MPF) activation.
Area of Science:
- Cellular and Molecular Biology
- Reproductive Biology
- Developmental Biology
Background:
- Progesterone induces oocyte maturation in amphibians, releasing prophase I arrest and activating maturation-promoting factor (MPF).
- The signal transduction pathway involves negative regulation of cAMP-dependent protein kinase (PKA) and synthesis of proteins like c-Mos.
- The role of the Mos/mitogenic activated protein kinase (MAP kinase) pathway in Cdc2 activation remains controversial.
Purpose of the Study:
- To discuss current progress on molecular mechanisms of progesterone-induced MPF activation.
- To present recent results on progesterone's role in oocyte maturation.
- To propose a model resolving inconsistencies regarding the Mos/MAP kinase pathway's function.
Main Methods:
- The study discusses existing research and presents new experimental results.
- Focuses on molecular mechanisms of signal transduction.
- Investigates the roles of PKA, c-Mos, and MAP kinase in MPF activation.
Main Results:
- Progesterone's action involves PKA inhibition and c-Mos synthesis.
- The Mos/MAP kinase pathway is implicated in MPF activation.
- Inconsistencies in the pathway's role are addressed by a proposed model.
Conclusions:
- A model is proposed to explain the molecular mechanisms of progesterone-induced MPF activation.
- The model aims to resolve controversies surrounding the Mos/MAP kinase pathway's involvement.
- This research contributes to understanding oocyte maturation regulation.
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