Asymmetric recruitment and actin dependent cortical flows drive the neuroblast polarity cycle

  1. Chet Huan Oon
  2. Ken Prehoda  Is a corresponding author
  1. University of Oregon, United States


During the asymmetric divisions of Drosophila neuroblasts, the Par polarity complex cycles between the cytoplasm and an apical cortical domain that restricts differentiation factors to the basal cortex. We used rapid imaging of the full cell volume to uncover the dynamic steps that underlie transitions between neuroblast polarity states. Initially the Par proteins aPKC and Bazooka form discrete foci at the apical cortex. Foci grow into patches that together comprise a discontinuous, unorganized structure. Coordinated cortical flows that begin near metaphase and are dependent on the actin cytoskeleton rapidly transform the patches into a highly organized apical cap. At anaphase onset, the cap disassembles as the cortical flow reverses direction towards the emerging cleavage furrow. Following division, cortical patches dissipate into the cytoplasm allowing the neuroblast polarity cycle to begin again. Our work demonstrates how neuroblasts use asymmetric recruitment and cortical flows to dynamically polarize during asymmetric division cycles.

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

Article and author information

Author details

  1. Chet Huan Oon

    Institute of Molecular Biology, Department of Chemistry and Biochemistry, University of Oregon, Eugene, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Ken Prehoda

    Institute of Molecular Biology, Department of Chemistry and Biochemistry, University of Oregon, Eugene, United States
    For correspondence
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4214-6158


National Institute of General Medical Sciences (GM127092)

  • Ken Prehoda

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

Reviewing Editor

  1. Yukiko M Yamashita, University of Michigan, United States

Publication history

  1. Received: February 5, 2019
  2. Accepted: May 7, 2019
  3. Accepted Manuscript published: May 8, 2019 (version 1)
  4. Version of Record published: May 17, 2019 (version 2)


© 2019, Oon & Prehoda

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. Chet Huan Oon
  2. Ken Prehoda
Asymmetric recruitment and actin dependent cortical flows drive the neuroblast polarity cycle
eLife 8:e45815.

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