We introduce a method for rapid screening of system-wide kinase activation states. Our approach relies on targeted quantification of evolutionary conserved activator sites, allowing the omission of the current bias toward well- studied kinases with known kinase – substrate relationships. Universally applicable to all types of human samples, the method is characterized by high sensitivity and throughput, providing extensive coverage of the human kinome, uncovering insights into kinase activation states in various molecular processes.
