1. Cell Biology
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Multi-phosphorylation reaction and clustering tune Pom1 gradient mid-cell levels according to cell size

  1. Veneta Gerganova
  2. Charlotte Floderer
  3. Anna Archetti
  4. Laetitia Michon
  5. Lina Carlini
  6. Thais Reichler
  7. Suliana Manley  Is a corresponding author
  8. Sophie G Martin  Is a corresponding author
  1. University of Lausanne, Switzerland
  2. École Polytechnique Fédérale de Lausanne (EPFL), Switzerland
  3. École Polytechnique Fédérale de Lausanne, Switzerland
Research Article
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Cite this article as: eLife 2019;8:e45983 doi: 10.7554/eLife.45983

Abstract

Protein concentration gradients pattern developing organisms and single cells. In Schizosaccharomyces pombe rod-shaped cells, Pom1 kinase forms gradients with maxima at cell poles. Pom1 controls the timing of mitotic entry by inhibiting Cdr2, which forms stable membrane-associated nodes at mid-cell. Pom1 gradients rely on membrane association regulated by a phosphorylation-dephosphorylation cycle and lateral diffusion modulated by clustering. Using quantitative PALM imaging, we find individual Pom1 molecules bind the membrane too transiently to diffuse from pole to mid-cell. Instead we propose they exchange within longer-lived clusters forming the functional gradient unit. An allelic series blocking auto-phosphorylation shows multi-phosphorylation shapes and buffers the gradient to control mid-cell levels, which represent the critical Cdr2-regulating pool. TIRF imaging of this cortical pool demonstrates more Pom1 overlaps with Cdr2 in short than long cells, consistent with Pom1 inhibition of Cdr2 decreasing with cell growth. Thus, the gradients modulate Pom1 mid-cell levels according to cell size.

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All data generated during this study are included in the manuscript and supporting files.

Article and author information

Author details

  1. Veneta Gerganova

    Department of Fundamental Microbiology, University of Lausanne, Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  2. Charlotte Floderer

    Institute of Physics, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  3. Anna Archetti

    Institute of Physics, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9049-3176
  4. Laetitia Michon

    Department of Fundamental Microbiology, University of Lausanne, Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  5. Lina Carlini

    Institute of Physics, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  6. Thais Reichler

    Institute of Physics, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  7. Suliana Manley

    Laboratory of Experimental Biophysics, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
    For correspondence
    suliana.manley@epfl.ch
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4755-4778
  8. Sophie G Martin

    Department of Fundamental Microbiology, University of Lausanne, Lausanne, Switzerland
    For correspondence
    Sophie.Martin@unil.ch
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5317-2557

Funding

Swiss National Science Foundation (CRSII3_160728)

  • Suliana Manley
  • Sophie G Martin

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

Reviewing Editor

  1. Mohan K Balasubramanian, University of Warwick, United Kingdom

Publication history

  1. Received: February 11, 2019
  2. Accepted: May 2, 2019
  3. Accepted Manuscript published: May 3, 2019 (version 1)
  4. Version of Record published: June 7, 2019 (version 2)

Copyright

© 2019, Gerganova 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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