The Xenopus Cell Cycle

An Overview
  • Anna Philpott
  • P. Renee Yew
Part of the Methods in Molecular Biology™ book series (MIMB, volume 296)


Oocytes, eggs, and embryos from the frog Xenopus laevis have been an important model system for studying cell cycle regulation for several decades. First, progression through meiosis in the oocyte has been extensively investigated. Oocyte maturation has been shown to involve complex networks of signal transduction pathways, culminating in the cyclic activation and inactivation of maturation promoting factor (MPF), which is composed of cyclin B and cdc2. After fertilization, the early embryo undergoes rapid simplified cell cycles, which have been recapitulated in cell-free extracts of Xenopus eggs. Experimental manipulation of these extracts has given a wealth of biochemical information about the cell cycle, particularly concerning DNA replication and mitosis. Finally, cells of older embryos adopt a more somatictype cell cycle and have been used to study the balance between cell cycle and differentiation during development.

Key Words

Xenopus cell cycle oocyte egg, embryo DNA replication initiation meiosis mitosis midblastula transition MPF cdk cyclin APC/C ubiquitin proteolysis 


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Copyright information

© Humana Press Inc. 2005

Authors and Affiliations

  • Anna Philpott
  • P. Renee Yew

There are no affiliations available

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