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Assessing mechanical agency during apical apoptotic cell extrusion
Sommer Anjum1,2, Llaran Turner3,4, Youmna Atieh3
1Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15260, USA.
Iscience
|November 7, 2024
Summary
Epithelial cells are removed through a process called extrusion, which is mainly driven by cell-autonomous mechanics. This study models cell extrusion dynamics in zebrafish to understand tissue homeostasis.
Area of Science:
- Cell biology
- Biophysics
- Developmental biology
Background:
- Epithelial homeostasis relies on removing defective cells.
- Controlled cell death and extrusion eliminate unfit, excess, and dying cells in larval zebrafish tail fins.
- Cell extrusion involves oscillations in cell area for both the extruding cell and its neighbors.
Purpose of the Study:
- To develop a biophysical model of cell extrusion.
- To explore the roles of autonomous and non-autonomous mechanics in cell extrusion.
- To investigate the influence of biophysical properties and tissue-wide factors on extrusion dynamics.
Main Methods:
- Developed a biophysical model of cell extrusion.
- Varied biophysical properties of extruding cells and neighbors.
- Adjusted oscillatory behaviors, tissue-wide cell density, and viscosity.
Main Results:
- Cell-autonomous processes significantly contribute to extrusion dynamics.
- The mechanical microenvironment plays a less pronounced role in extrusion.
- Initial resistance to extrusion by some cells affects the process duration.
Conclusions:
- Cell-autonomous mechanics are primary drivers of cell extrusion.
- The mechanical microenvironment has a secondary influence on extrusion.
- Understanding these dynamics is key to maintaining epithelial tissue health and homeostasis.
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