Role of competition between polarity sites in establishing a unique front

  1. Chi-Fang Wu
  2. Jian-Geng Chiou
  3. Maria Minakova
  4. Benjamin Woods
  5. Denis Tsygankov
  6. Trevin R Zyla
  7. Natasha S Savage
  8. Timothy C Elston
  9. Daniel J Lew  Is a corresponding author
  1. Duke University School of Medicine, United States
  2. University of North Carolina at Chapel Hill, United States
  3. University of Liverpool, United Kingdom

Abstract

Polarity establishment in many cells is thought to occur via positive feedback that reinforces even tiny asymmetries in polarity protein distribution. Cdc42 and related GTPases are activated and accumulate in a patch of the cortex that defines the front of the cell. Positive feedback enables spontaneous polarization triggered by stochastic fluctuations, but as such fluctuations can occur at multiple locations, how do cells ensure that they make only one front? In polarizing cells of the model yeast Saccharomyces cerevisiae, positive feedback can trigger growth of several Cdc42 clusters at the same time, but this multi-cluster stage rapidly evolves to a single-cluster state, which then promotes bud emergence. By manipulating polarity protein dynamics, we show that resolution of multi-cluster intermediates occurs through a greedy competition between clusters to recruit and retain polarity proteins from a shared intracellular pool.

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Author details

  1. Chi-Fang Wu

    Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Jian-Geng Chiou

    Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Maria Minakova

    Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Benjamin Woods

    Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Denis Tsygankov

    Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Trevin R Zyla

    Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, United States
    Competing interests
    The authors declare that no competing interests exist.
  7. Natasha S Savage

    Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  8. Timothy C Elston

    Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, United States
    Competing interests
    The authors declare that no competing interests exist.
  9. Daniel J Lew

    Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, United States
    For correspondence
    daniel.lew@duke.edu
    Competing interests
    The authors declare that no competing interests exist.

Copyright

© 2015, Wu 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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https://doi.org/10.7554/eLife.11611

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