A dynamic mechanism for allosteric activation of Aurora kinase A by activation loop phosphorylation
- University of Minnesota, United States
- Memorial Sloan Kettering Cancer Center, United States
Abstract
Many eukaryotic protein kinases are activated by phosphorylation on a specific conserved residue in the regulatory activation loop, a post-translational modification thought to stabilize the active DFG-In state of the catalytic domain. Here we use a battery of spectroscopic methods that track different catalytic elements of the kinase domain to show that the ~100-fold activation of the mitotic kinase Aurora A (AurA) by phosphorylation occurs without a population shift from the DFG-Out to the DFG-In state, and that the activation loop of the activated kinase remains highly dynamic. Instead, molecular dynamics simulations and electron paramagnetic resonance experiments show that phosphorylation triggers a switch within the DFG-In subpopulation from an autoinhibited DFG-In substate to an active DFG-In substate, leading to catalytic activation. This mechanism raises new questions about the functional role of the DFG-Out state in protein kinases.
Article and author information
Author details
Nicholas M Levinson
Funding
National Institutes of Health (R00 Award GM102288)
- Nicholas M Levinson
National Institutes of Health (R21 Award CA217695)
- Nicholas M Levinson
National Institutes of Health (NRSA Award F32GM120817)
- Emily F Ruff
National Institutes of Health (P30-CA008748)
- John D Chodera
National Institutes of Health (GM121505)
- John D Chodera
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Ruff et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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