1. Cell Biology
  2. Physics of Living Systems
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How cells determine the number of polarity sites

  1. Jian-geng Chiou
  2. Kyle D Moran
  3. Daniel J Lew  Is a corresponding author
  1. Duke University, United States
Research Article
  • Cited 0
  • Views 419
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Cite this article as: eLife 2021;10:e58768 doi: 10.7554/eLife.58768

Abstract

The diversity of cell morphologies arises, in part, through regulation of cell polarity by Rho-family GTPases. A poorly understood but fundamental question concerns the regulatory mechanisms by which different cells generate different numbers of polarity sites. Mass-conserved activator-substrate (MCAS) models that describe polarity circuits develop multiple initial polarity sites, but then those sites engage in competition, leaving a single winner. Theoretical analyses predicted that competition would slow dramatically as GTPase concentrations at different polarity sites increase towards a 'saturation point', allowing polarity sites to coexist. Here, we test this prediction using budding yeast cells, and confirm that increasing the amount of key polarity proteins results in multiple polarity sites and simultaneous budding. Further, we elucidate a novel design principle whereby cells can switch from competition to equalization among polarity sites. These findings provide insight into how cells with diverse morphologies may determine the number of polarity sites.

Data availability

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

Article and author information

Author details

  1. Jian-geng Chiou

    Pharmacology and Cancer Biology, Duke University, Durham, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3246-5841
  2. Kyle D Moran

    Pharmacology and Cancer Biology, Duke University, Durham, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Daniel J Lew

    Pharmacology and Cancer Biology, Duke University, Durham, United States
    For correspondence
    daniel.lew@duke.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7482-3585

Funding

National Institutes of Health (MIRA R35GM122488)

  • Daniel J Lew

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: May 10, 2020
  2. Accepted: April 23, 2021
  3. Accepted Manuscript published: April 26, 2021 (version 1)

Copyright

© 2021, Chiou 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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