Functional cross-talk between allosteric effects of activating and inhibiting ligands underlies PKM2 regulation
- The Francis Crick Institute, United Kingdom
- University of Manchester, United Kingdom
- King's College London, United Kingdom
Abstract
Several enzymes can simultaneously interact with multiple intracellular metabolites, however, how the allosteric effects of distinct ligands are integrated to coordinately control enzymatic activity remains poorly understood. We addressed this question using, as a model system, the glycolytic enzyme pyruvate kinase M2 (PKM2). We show that the PKM2 activator fructose 1,6-bisphosphate (FBP) alone promotes tetramerisation and increases PKM2 activity, but addition of the inhibitor L-phenylalanine (Phe) prevents maximal activation of FBP-bound PKM2 tetramers. We developed a method, AlloHubMat, that uses eigenvalue decomposition of mutual information derived from molecular dynamics trajectories to identify residues that mediate FBP-induced allostery. Experimental mutagenesis of these residues identified PKM2 variants in which activation by FBP remains intact but cannot be attenuated by Phe. Our findings reveal residues involved in FBP-induced allostery that enable the integration of allosteric input from Phe and provide a paradigm for the coordinate regulation of enzymatic activity by simultaneous allosteric inputs.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
Article and author information
Author details
Dimitrios Anastasiou
Funding
Cancer Research UK (FC001033)
- Dimitrios Anastasiou
Wellcome (FC001033)
- Dimitrios Anastasiou
Medical Research Council (FC001033)
- Dimitrios Anastasiou
Francis Crick Institute (FC001033)
- Dimitrios Anastasiou
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2019, Macpherson 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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