A dynamic charge-charge interaction modulates PP2A:B56 substrate recruitment
- University of Arizona, United States
- University of Copenhagen, Denmark
- Geisel School of Medicine at Dartmouth, United States
- University of Copenhagen, Germany
Abstract
The recruitment of substrates by the ser/thr protein phosphatase 2A (PP2A) is poorly understood, limiting our understanding of PP2A-regulated signaling. Recently, the first PP2A:B56 consensus binding motif, LxxIxE, was identified. However, most validated LxxIxE motifs bind PP2A:B56 with micromolar affinities, suggesting that additional motifs exist to enhance PP2A:B56 binding. Here, we report the requirement of a positively charged motif in a subset of PP2A:B56 interactors, including KIF4A, to facilitate B56 binding via dynamic, electrostatic interactions. Using molecular and cellular experiments, we show that a conserved, negatively charged groove on B56 mediates dynamic binding. We also discovered that this positively charged motif, in addition to facilitating KIF4A dephosphorylation, is essential for condensin I binding, a function distinct and exclusive from PP2A-B56 binding. Together, these results reveal how dynamic, charge-charge interactions fine-tune the interactions mediated by specific motifs, providing a new framework for understanding how PP2A regulation drives cellular signaling.
Data availability
All NMR chemical shifts have been deposited in the BioMagResBank (BMRB 27913). Atomic coordinates and structure factors have been deposited in the Protein Data Bank (6OYL, 6VRO). The mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium (Vizcaíno et al., 2014) through the PRIDE partner repository (PXD013886).
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Atomic coordinates and structure factorsProtein Data Bank, 6OYL.
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Atomic coordinates and structure factorsProtein Data Bank, 6VRO.
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Backbone 1H, 13C, and 15N Chemical Shift Assignments for the C-terminal Fragment of a Kinesin KIF4A VariantBiological Magnetic Resonance Data Bank, 27913.
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Mass spectrometry proteomics dataProteome Exchange, PXD013886.
Article and author information
Author details
Arminja N Kettenbach
Funding
National Institute of General Medical Sciences (R35GM119455)
- Arminja N Kettenbach
National Institute of General Medical Sciences (P20GM113132)
- Arminja N Kettenbach
National Institute of General Medical Sciences (R01GM098482)
- Rebecca Page
National Institute of Neurological Disorders and Stroke (R01NS091336)
- Wolfgang Peti
National Institute of General Medical Sciences (R01GM134683)
- Wolfgang Peti
Novo Nordisk (NNF14CC0001)
- Jakob Nilsson
Independent Research Fund Denmark (DFF-7016-00086)
- Jakob Nilsson
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Wang 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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A dynamic charge-charge interaction modulates PP2A:B56 substrate recruitment
eLife 9:e55966.
https://doi.org/10.7554/eLife.55966
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