Coimmunoprecipitation is one of the most useful techniques for revealing protein-protein interactions. Good negative controls to verify the specificity of the coimmunoprecipitation procedure are (1) performing the same immunoprecipitation experiment using beads coupled to the preimmune serum and (2) probing the Western blot with antibodies against protein known not to interact with the coimmunoprecipitated proteins under physiological conditions.

Protocol: Protein Coimmunoprecipitation in Arabidopsis Protocol