Combinatorial deployment of F-actin regulators to build complex 3D actin structures in vivo

  1. Yi Xie
  2. Rashmi Budhathoki
  3. J Todd Blankenship  Is a corresponding author
  1. University of Denver, United States

Abstract

Despite extensive studies on the actin regulators that direct microfilament dynamics, how these regulators are combinatorially utilized in organismal tissues to generate 3D structures is an unresolved question. Here, we present an in-depth characterization of cortical actin cap dynamics and their regulation in vivo. We identify rapid phases of initiation, expansion, duplication and disassembly and examine the functions of 7 different Actin and/or Nucleator Regulators (ANRPs) in guiding these behaviors. We find ANRPs provide distinct activities in building actin cap morphologies – specifically, while DPod1 is a major regulator of actin intensities, Cortactin is required for continued cortical growth, while Coronin functions in both growth and intensity and is required for Cortactin localization to the cap periphery. Unexpectedly, cortical actin populations recover more rapidly after regulator disruption, suggestive of a deep competition for limited G-actin pools, and we measure in vivo Arp2/3 recruitment efficiencies through an ectopic relocalization strategy. Our results illustrate how the coordination of multiple actin regulators can orchestrate organized and dynamic actin structures in a developmental system.

Data availability

All data generated or analyzed during this study are included in the manuscript and supporting files. Transgenic stocks have been made freely available.

Article and author information

Author details

  1. Yi Xie

    Biological Sciences, University of Denver, Denver, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Rashmi Budhathoki

    Biological Sciences, University of Denver, Denver, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. J Todd Blankenship

    Biological Sciences, University of Denver, Denver, United States
    For correspondence
    jblanke4@du.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8687-9527

Funding

National Institute of General Medical Sciences (R01GM127447)

  • Yi Xie

National Institute of General Medical Sciences (R01GM126422)

  • Yi Xie

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

Version history

  1. Received: September 11, 2020
  2. Accepted: May 4, 2021
  3. Accepted Manuscript published: May 5, 2021 (version 1)
  4. Version of Record published: May 25, 2021 (version 2)

Copyright

© 2021, Xie 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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  1. Yi Xie
  2. Rashmi Budhathoki
  3. J Todd Blankenship
(2021)
Combinatorial deployment of F-actin regulators to build complex 3D actin structures in vivo
eLife 10:e63046.
https://doi.org/10.7554/eLife.63046

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https://doi.org/10.7554/eLife.63046

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