1. Biochemistry and Chemical Biology
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Mechanisms of PDZ domain scaffold assembly illuminated by use of supported cell membrane sheets

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Cite this article as: eLife 2019;8:e39180 doi: 10.7554/eLife.39180

Abstract

PDZ domain scaffold proteins are molecular modules orchestrating cellular signaling in space and time. Here, we investigate assembly of PDZ scaffolds using supported cell membrane sheets, a unique experimental setup enabling direct access to the intracellular face of the cell membrane. Our data demonstrate how multivalent protein-protein and protein-lipid interactions provide critical avidity for the strong binding between the PDZ domain scaffold proteins, PICK1 and PSD-95, and their cognate transmembrane binding partners. The kinetics of the binding were remarkably slow and binding strength two-three orders of magnitude higher than the intrinsic affinity for the isolated PDZ interaction. Interestingly, discrete changes in the intrinsic PICK1 PDZ affinity did not affect overall binding strength but instead revealed dual scaffold modes for PICK1. Our data supported by simulations suggest that intrinsic PDZ domain affinities are finely tuned and encode specific cellular responses, enabling multiplexed cellular functions of PDZ scaffolds.

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Author details

  1. Simon Erlendsson

    Department of Neuroscience, 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:" 0000-0002-6378-870X
  2. Thor Seneca Thorsen

    Department of Neuroscience, University of Copenhagen, Copenhagen, Denmark
    Competing interests
    The authors declare that no competing interests exist.
  3. Georges Vauquelin

    Department of Biotechnology, Free University Brussels (VUB), Brussels, Belgium
    Competing interests
    The authors declare that no competing interests exist.
  4. Ina Ammendrup-Johnsen

    Department of Neuroscience, University of Copenhagen, Copenhagen, Denmark
    Competing interests
    The authors declare that no competing interests exist.
  5. Volker Wirth

    Department of Chemistry, University of Copenhagen, Copenhagen, Denmark
    Competing interests
    The authors declare that no competing interests exist.
  6. Karen L Martinez

    Department of Chemistry, University of Copenhagen, Copenhagen, Denmark
    Competing interests
    The authors declare that no competing interests exist.
  7. Kaare Teilum

    Department of Biology, 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:" 0000-0001-6919-1982
  8. Ulrik Gether

    Department of Neuroscience, University of Copenhagen, Copenhagen, Denmark
    Competing interests
    The authors declare that no competing interests exist.
  9. Kenneth Lindegaard Madsen

    Department of Neuroscience, University of Copenhagen, Copenhagen, Denmark
    For correspondence
    lnp353@ku.dk
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9274-6691

Funding

National Institutes of Health

  • Ulrik Gether

Lundbeckfonden

  • Ulrik Gether

Novo Nordisk

  • Ulrik Gether

Det Frie Forskningsråd

  • Ulrik Gether

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Patricia Bassereau, Institut Curie, France

Publication history

  1. Received: June 13, 2018
  2. Accepted: January 2, 2019
  3. Accepted Manuscript published: January 3, 2019 (version 1)
  4. Version of Record published: January 24, 2019 (version 2)

Copyright

© 2019, Erlendsson 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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