Anillin regulates epithelial cell mechanics by structuring the medial-apical actomyosin network
Abstract
Cellular forces sculpt organisms during development, while misregulation of cellular mechanics can promote disease. Here, we investigate how the actomyosin scaffold protein Anillin contributes to epithelial mechanics in Xenopus laevis embryos. Increased mechanosensitive recruitment of Vinculin to cell-cell junctions when Anillin is overexpressed, suggested that Anillin promotes junctional tension. However, junctional laser ablation unexpectedly showed that junctions recoil faster when Anillin is depleted and slower when Anillin is overexpressed. Unifying these findings, we demonstrate that Anillin regulates medial-apical actomyosin. Medial-apical laser ablation supports the conclusion that that tensile forces are stored across the apical surface of epithelial cells, and Anillin promotes the tensile forces stored in this network. Finally, we show that Anillin's effects on cellular mechanics impact tissue-wide mechanics. These results reveal Anillin as a key regulator of epithelial mechanics and lay the groundwork for future studies on how Anillin may contribute to mechanical events in development and disease.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for: Figure 1, Figure 2, Figure 3, Figure 4, Figure 6, Figure 7 and Figure 8
Article and author information
Author details
Funding
National Institute of General Medical Sciences (R01 GM112794)
- Ann L Miller
Eunice Kennedy Shriver National Institute of Child Health and Human Development (R01 HD04475)
- Lance A Davidson
National Heart, Lung, and Blood Institute (R56 HL134195)
- Lance A Davidson
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All studies conducted using Xenopus laevis embryos strictly adhered to the compliance standards of the US Department of Health and Human Services Guide for the Care and Use of Laboratory Animals and were approved by the University of Michigan's Institutional Animal Care and Use Committee (PRO00007339).
Copyright
© 2019, Arnold 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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