Dynamic Equilibrium of the Aurora A Kinase Activation Loop Revealed by Single-Molecule Spectroscopy.
Abstract
The conformation of the activation loop (T-loop) of protein kinases underlies enzymatic activity and influences the binding of small-molecule inhibitors. By using single-molecule fluorescence spectroscopy, we have determined that phosphorylated Aurora A kinase is in dynamic equilibrium between a DFG-in-like active T-loop conformation and a DFG-out-like inactive conformation, and have measured the rate constants of interconversion. Addition of the Aurora A activating protein TPX2 shifts the equilibrium towards an active T-loop conformation whereas addition of the inhibitors MLN8054 and CD532 favors an inactive T-loop. We show that Aurora A binds TPX2 and MLN8054 simultaneously and provide a new model for kinase conformational behavior. Our approach will enable conformation-specific effects to be integrated into inhibitor discovery across the kinome, and we outline some immediate consequences for structure-based drug discovery.
Collections
Subject
Humans
Protein Kinase Inhibitors
Ligands
Fluorescence
Models, Molecular
Aurora Kinase A
Research team
Medicinal Chemistry 1
Language
eng
License start date
2017-09
Citation
Angewandte Chemie (International ed. in English), 2017, 56 (38), pp. 11409 - 11414