A dynamic charge-charge interaction modulates PP2A:B56 substrate recruitment

  1. Xinru Wang
  2. Dimitriya H Garvanska
  3. Isha Nasa
  4. Yumi Ueki
  5. Gang Zhang
  6. Arminja N Kettenbach
  7. Wolfgang Peti
  8. Jakob Nilsson  Is a corresponding author
  9. Rebecca Page  Is a corresponding author
  1. University of Arizona, United States
  2. University of Copenhagen, Denmark
  3. Geisel School of Medicine at Dartmouth, United States
  4. 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).

The following data sets were generated
The following previously published data sets were used

Article and author information

Author details

  1. Xinru Wang

    Department of Chemistry and Biochemistry, University of Arizona, Tucson, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5994-707X
  2. Dimitriya H Garvanska

    The Novo Nordisk Foundation Center for Protein Research, University of Copenhagen, Copenhagen, Denmark
    Competing interests
    The authors declare that no competing interests exist.
  3. Isha Nasa

    Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Lebanon, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7699-795X
  4. Yumi Ueki

    The Novo Nordisk Foundation Center for Protein Research, University of Copenhagen, Copenhagen, Denmark
    Competing interests
    The authors declare that no competing interests exist.
  5. Gang Zhang

    The Novo Nordisk Foundation Center for Protein Research, University of Copenhagen, Copenhagen, Denmark
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7697-7203
  6. Arminja N Kettenbach

    Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Lebanon, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3979-4576
  7. Wolfgang Peti

    Department of Chemistry and Biochemistry, University of Arizona, Tucson, United States
    Competing interests
    The authors declare that no competing interests exist.
  8. Jakob Nilsson

    The Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Germany
    For correspondence
    jakob.nilsson@cpr.ku.dk
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4100-1125
  9. Rebecca Page

    Department of Chemistry and Biochemistry, University of Arizona, Tucson, United States
    For correspondence
    rebeccapage@email.arizona.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4645-1232

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.

Reviewing Editor

  1. Tony Hunter, Salk Institute for Biological Studies, United States

Version history

  1. Received: February 12, 2020
  2. Accepted: March 14, 2020
  3. Accepted Manuscript published: March 20, 2020 (version 1)
  4. Version of Record published: March 31, 2020 (version 2)

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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  1. Xinru Wang
  2. Dimitriya H Garvanska
  3. Isha Nasa
  4. Yumi Ueki
  5. Gang Zhang
  6. Arminja N Kettenbach
  7. Wolfgang Peti
  8. Jakob Nilsson
  9. Rebecca Page
(2020)
A dynamic charge-charge interaction modulates PP2A:B56 substrate recruitment
eLife 9:e55966.
https://doi.org/10.7554/eLife.55966

Share this article

https://doi.org/10.7554/eLife.55966

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