1. Cell Biology
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ADF and cofilin-1 collaborate to promote cortical actin flow and the leader bleb-based migration of confined cells

  1. Maria F Ullo
  2. Jeremy S Logue  Is a corresponding author
  1. Albany Medical College, United States
Research Article
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Cite this article as: eLife 2021;10:e67856 doi: 10.7554/eLife.67856


Melanoma cells have been shown to undergo fast amoeboid (leader bleb-based) migration, requiring a single large bleb for migration. In leader blebs, is a rapid flow of cortical actin that drives the cell forward. Using RNAi, we find that co-depleting cofilin-1 and ADF led to a large increase in cortical actin, suggesting that both proteins regulate cortical actin. Furthermore, severing factors can promote contractility through the regulation of actin architecture. However, RNAi of cofilin-1 but not ADF led to a significant decrease in cell stiffness. We found cofilin-1 to be enriched at leader bleb necks, whereas RNAi of cofilin-1 and ADF reduced bleb sizes and the frequency of motile cells. Strikingly, cells without cofilin-1 and ADF had blebs with abnormally long necks. Many of these blebs failed to retract and displayed slow actin turnover. Collectively, our data identifies cofilin-1 and ADF as actin remodeling factors required for fast amoeboid migration.

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Source data files for Figures 1, 2, and 5 have been provided.

Article and author information

Author details

  1. Maria F Ullo

    Regenerative and Cancer Cell Biology, Albany Medical College, Albany, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Jeremy S Logue

    Regenerative and Cancer Cell Biology, Albany Medical College, Albany, 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:" 0000-0002-5274-2052


Melanoma Research Alliance (688232)

  • Maria F Ullo
  • Jeremy S Logue

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

Reviewing Editor

  1. Alphee Michelot, Institut de Biologie du Développement, France

Publication history

  1. Received: February 25, 2021
  2. Accepted: June 22, 2021
  3. Accepted Manuscript published: June 25, 2021 (version 1)
  4. Version of Record published: July 2, 2021 (version 2)


© 2021, Ullo & Logue

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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