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Regulated spindle orientation buffers tissue growth in the epidermis
Angel Morrow1, Julie Underwood1, Lindsey Seldin1,2
1Department of Dermatology, Duke University, Durham, United States.
Elife
|October 3, 2019
Summary
Spindle orientation controls tissue balance by adjusting asymmetric cell divisions. This mechanism buffers changes in cell proliferation, preventing tissue loss or overgrowth, crucial for mammalian skin homeostasis.
Area of Science:
- Cell biology
- Developmental biology
- Tissue homeostasis
Background:
- Tissue homeostasis relies on balancing progenitor cell proliferation and loss.
- Dysregulation can lead to tissue loss or overgrowth.
Purpose of the Study:
- To investigate the role of spindle orientation and asymmetric cell divisions in maintaining tissue homeostasis.
- To understand how these processes buffer changes in cell proliferation.
Main Methods:
- Genetic manipulation to alter spindle orientation.
- Pharmacologic interventions to induce hyper- and hypoproliferative conditions.
- Analysis of asymmetric cell division frequency.
- Investigating the role of K-Ras signaling.
Main Results:
- Asymmetric cell divisions increased in hyperproliferative states and decreased in hypoproliferative states.
- Active K-Ras signaling elevated the frequency of asymmetric cell divisions.
- Disrupting spindle orientation with active K-Ras caused significant tissue overgrowth.
Conclusions:
- Spindle orientation and asymmetric cell division are key mechanisms buffering mammalian skin homeostasis against perturbations.
- These processes are critical for preventing uncontrolled tissue growth.
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