Watson, N. A. et al. Nat. Commun. 11, 1684 (2020).

Kinase phosphorylation site dependencies have been studied to identify targets for a kinase of interest; however, identification of kinases that phosphorylate a particular site is not routine. To address this problem, Watson et al. have developed KiPIK (kinase inhibitor profiling to identify kinases). The researchers collected data for a large number of kinase inhibitors on in vitro inhibitory activity against a panel of about 500 recombinant human kinases. This information can be interpreted as inhibition fingerprint for kinases. Next, the researchers obtained cell extracts exhibiting phosphorylation activity of interest and screened against the inhibitors in the panel. Quantification of substrate phosphorylation in the presence of each inhibitor provides the inhibition fingerprint, which can then be matched with the previously determined fingerprints for recombinant kinases. The authors have validated this method on many known phosphorylation sites, as well as made predictions for unknown kinases.