Regulated spindle orientation buffers tissue growth in the epidermis
Abstract
Tissue homeostasis requires a balance between progenitor cell proliferation and loss. Mechanisms that maintain this robust balance are needed to avoid tissue loss or overgrowth. Here we demonstrate that regulation of spindle orientation/asymmetric cell divisions is one mechanism that is used to buffer changes in proliferation and tissue turnover in mammalian skin. Genetic and pharmacologic experiments demonstrate that asymmetric cell divisions were increased in hyperproliferative conditions and decreased under hypoproliferative conditions. Further, active K-Ras also increased the frequency of asymmetric cell divisions. Disruption of spindle orientation in combination with constitutively active K-Ras resulted in massive tissue overgrowth. Together, these data highlight the essential roles of spindle orientation in buffering tissue homeostasis in response to perturbations.
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There are no large datasets associated with this manuscript.
Article and author information
Author details
Funding
National Institute of Arthritis and Musculoskeletal and Skin Diseases (R01AR067203)
- Terry Lechler
National Institute of Arthritis and Musculoskeletal and Skin Diseases (R01AR055926)
- Terry Lechler
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Beate Maria Lichtenberger, Medical University of Vienna, Austria
Ethics
Animal experimentation: This study was performed in accordance with recommendation in the Guide for the Care and Use fo Laboratory Animals of the NIH. Animals were handled according to an approved IACUC protocol (A092-18-04) from Duke University.
Version history
- Received: May 15, 2019
- Accepted: October 1, 2019
- Accepted Manuscript published: October 2, 2019 (version 1)
- Version of Record published: October 15, 2019 (version 2)
Copyright
© 2019, Morrow 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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