Abstract
Few methods are available to discover the cellular kinase that phosphorylates a specific amino acid, or phosphosite, on a protein. In addition, identifying the associated proteins bound near a phosphosite during phosphorylation would provide insights into cell biology and signaling. Here, we report K-CLASP (Kinase Catalyzed CrossLinking And Streptavidin Purification) as a method for both phosphosite-specific kinase identification and the discovery of kinase interacting proteins. K-CLASP offers a powerful tool to discover unanticipated protein-protein interactions in phosphorylation-mediated biological events.