Assaying Cdc25 Phosphatase Activity

  • Ingo Hassepass
  • Ingrid Hoffmann
Part of the Methods in Molecular Biology book series (MIMB, volume 281)


To determine the activity of all human Cdc25 phosphatases, two different methods are described. For assaying phosphatase activities of recombinant Cdc25 proteins produced in Escherichia coli or insect cells, a fluorimetric assay using fluorescein diphosphate (FDP) as a substrate is recommended. To analyze endogenous Cdc25 phosphatase activities of immuno-precipitates from total cellular extracts, the physiological substrate Cdk1/cyclin B1 is most sensitive.

Key Words

Cdc25 phosphatase Cdk cyclin cell cycle 


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Copyright information

© Humana Press Inc. 2004

Authors and Affiliations

  • Ingo Hassepass
    • 1
  • Ingrid Hoffmann
    • 2
  1. 1.Cell Cycle Control and CarcinogenesisGerman Cancer Research Center (DKFZ)HeidelbergGermany
  2. 2.Department of Applied Tumorvirology, Cell Cycle Control and Carcinogenesis (F045)German Cancer Research Center (DKFZ)HeidelbergGermany

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