Size-dependent patterns of cell proliferation and migration in freely-expanding epithelia
- Princeton University, United States
Abstract
The coordination of cell proliferation and migration in growing tissues is crucial in development and regeneration but remains poorly understood. Here, we find that, while expanding with an edge speed independent of initial conditions, millimeter-scale epithelial monolayers exhibit internal patterns of proliferation and migration that depend not on the current but on the initial tissue size, indicating memory effects. Specifically, the core of large tissues becomes very dense, almost quiescent, and ceases cell-cycle progression. In contrast, initially-smaller tissues develop a local minimum of cell density and a tissue-spanning vortex. To explain vortex formation, we propose an active polar fluid model with a feedback between cell polarization and tissue flow. Taken together, our findings suggest that expanding epithelia decouple their internal and edge regions, which enables robust expansion dynamics despite the presence of size and history-dependent patterns in the tissue interior.
Data availability
Representative raw datasets for each Figure are available at Zenodo DOI: 10.5281/zenodo.3858845Full raw dataset is hundreds of gigabytes due to the video data and can be provided upon request. Key analysis code provided at our github repository: Github DOI: 10.5281/zenodo.3861843
Article and author information
Author details
Funding
National Institutes of Health (1 R35GM133574-01)
- Daniel J Cohen
Human Frontiers of Science Program (LT000475/2018-C)
- Ricard Alert
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Heinrich 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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Size-dependent patterns of cell proliferation and migration in freely-expanding epithelia
eLife 9:e58945.
https://doi.org/10.7554/eLife.58945
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