Co-immunoprecipitation Assay for Blue Light-Dependent Protein Interactions in Plants

Co-immunoprecipitation (CoIP) assay has been used as a powerful and routine technique to detect in vivo protein-protein interactions. Not only can it probe stable interactions, but also it is applicable for semiquantitative and inducible protein associations. Here we describe the protocol for detecting blue light-dependent protein interactions, particularly for blue light receptor cryptochrome-mediated complex formation. In addition, we present some notes which may be helpful for common Co-IP study as well.