Coimmunoprecipitation Assay

  • Choogon Lee
Part of the Methods in Molecular Biology™ book series (MIMB, volume 362)


As with most other proteins, clock proteins physically interact with one another. Coimmunoprecipitation (coIP) is the most straightforward technique to study protein-protein interactions in vivo, if antibodies against the proteins of interest are available. To perform coIP, first an antibody against a target protein is coupled to Sepharose beads through protein A or G, then the complexes containing the target protein are immunoprecipitated with the antibody-coupled beads by centrifugation. Protein components in the complexes are visualized by Western blotting using antibodies specific to the different components.

Key Words

Coimmunoprecipitation protein-protein interactions protein A/G protein complexes 


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Copyright information

© Humana Press Inc. 2007

Authors and Affiliations

  • Choogon Lee
    • 1
  1. 1.Department of Biomedical SciencesFlorida State University College of MedicineTallahassee

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