Measurement of Geminin Activity in Xenopus Egg Extracts

  • Thomas J. McGarry
Part of the Methods in Molecular Biology™ book series (MIMB, volume 296)


Geminin is an unstable protein that inhibits DNA replication by interfering with the assembly of prereplication complex at replication origins. Geminin is thought to prevent a second round of replication during late S- or G2-phase. The protein is destroyed by ubiquitin-dependent proteolysis during mitosis, allowing a new round of replication in the next cell cycle. This chapter describes protocols for measuring the stability of geminin and two of its activities, the inhibition of replication and the inhibition of pre-RC loading.

Key Words

Geminin DNA Replication ubiquitin-dependent proteolysis prereplication complex rereplication cell cycle S-phase mitosis anaphase-promoting complex 


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Copyright information

© Humana Press Inc. 2005

Authors and Affiliations

  • Thomas J. McGarry

There are no affiliations available

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