Rapid detection of protein tyrosine kinase activity in recombinant yeast expressing a universal substrate

Yeast two-hybrid systems are powerful proteomics tools for the discovery of protein-protein interactions. However, these systems are typically unable to detect interactions dependent on post-translational modifications such as tyrosine phosphorylation. We report a novel yeast tribrid system that expresses a potentially universal protein tyrosine kinase (PTK) substrate to detect diverse PTKs. Validation with the oncogenic kinases v-Abl and v-Src, which exhibit divergent substrate specificities, demonstrated significant potential for cloning PTKs en masse from cDNA libraries.