Variations of intracellular density during the cell cycle arise from tip-growth regulation in fission yeast
- UCSF, United States
- Massachusetts Institute of Technology, United States
- Korea Institute of Science and Technology, Republic of Korea
- University of Amsterdam, Netherlands
- Stanford University, United States
Abstract
Intracellular density impacts the physical nature of the cytoplasm and can globally affect cellular processes, yet density regulation remains poorly understood. Here, using a new quantitative phase imaging method, we determined that dry-mass density in fission yeast is maintained in a narrow distribution and exhibits homeostatic behavior. However, density varied during the cell cycle, decreasing during G2, increasing in mitosis and cytokinesis, and dropping rapidly at cell birth. These density variations were explained by a constant rate of biomass synthesis, coupled to slowdown of volume growth during cell division and rapid expansion post-cytokinesis. Arrest at specific cell-cycle stages exacerbated density changes. Spatially heterogeneous patterns of density suggested links between density regulation, tip growth, and intracellular osmotic pressure. Our results demonstrate that systematic density variations during the cell cycle are predominantly due to modulation of volume expansion, and reveal functional consequences of density gradients and cell-cycle arrests.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Custom Matlab code used for image analysis has been posted online at the Github repository https://bitbucket.org/kchuanglab/quantitative-phase-imaging/src/master/.
Article and author information
Author details
Kerwyn Casey Huang
Funding
Swiss National Foundation (P2ELP3_172318)
- Pascal D Odermatt
Swiss National Foundation (P400PB_180872)
- Pascal D Odermatt
National Institute of General Medical Sciences (NIH GM056836)
- Fred Chang
Wellcome Trust (110275/Z/15/Z)
- Teemu P Miettinen
Chan Zuckerberg Initiative
- Kerwyn Casey Huang
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Odermatt 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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Variations of intracellular density during the cell cycle arise from tip-growth regulation in fission yeast
eLife 10:e64901.
https://doi.org/10.7554/eLife.64901
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