Scaling of subcellular actin structures with cell length through decelerated growth
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
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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