Scaling of subcellular actin structures with cell length through decelerated growth

  1. Shane G McInally
  2. Jane Kondev  Is a corresponding author
  3. Bruce L Goode  Is a corresponding author
  1. Brandeis University, United States

Abstract

How cells tune the size of their subcellular parts to scale with cell size is a fundamental question in cell biology. Until now, most studies on the size control of organelles and other subcellular structures have focused on scaling relationships with cell volume, which can be explained by limiting pool mechanisms. Here, we uncover a distinct scaling relationship with cell length rather than volume, revealed by mathematical modeling and quantitative imaging of yeast actin cables. The extension rate of cables decelerates as they approach the rear of the cell, until cable length matches cell length. Further, the deceleration rate scales with cell length. These observations are quantitatively explained by a 'balance-point' model, which stands in contrast to the limiting pool mechanisms and that senses the linear dimensions of the cell.

Data availability

All data points are shown in the main and supplemental figures, and all cell images and source code are archived at Zenodo.

Article and author information

Author details

  1. Shane G McInally

    Biology, Physics, Brandeis University, Waltham, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-6145-4581
  2. Jane Kondev

    Department of Physics, Brandeis University, Waltham, United States
    For correspondence
    kondev@brandeis.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7522-7144
  3. Bruce L Goode

    Department of Biology, Rosenstiel Basic Medical Science Research Center, Brandeis University, Waltham, United States
    For correspondence
    goode@brandeis.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6443-5893

Funding

National Institutes of Health (R35 GM134895)

  • Bruce L Goode

National Science Foundation (2010766)

  • Shane G McInally

National Science Foundation (DMR-1610737)

  • Jane Kondev

National Science Foundation (2011486)

  • Bruce L Goode

National Science Foundation (2011486)

  • Jane Kondev

Simons Foundation

  • Jane Kondev

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

Copyright

© 2021, McInally 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.68424

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