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Updated: Jul 6, 2026
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Imaging Plasma Membrane Deformations With pTIRFM
Published on: April 2, 2014
Dynamic Plasma Membrane Topography Linked With Arp2/3 Actin Network Induction During Cell Shape Change
1Department of Cell & Systems Biology, University of Toronto, Toronto, Canada.
Summary
Cell surface topography changes are mechanosensitive and drive cell shape changes. Local plasma membrane curvature directly influences actin network formation, remodeling cell structure.
Area of Science:
- Cell Biology
- Biophysics
- Mechanobiology
Background:
- Mesoscale changes in plasma membrane (PM) topography are crucial for cell shape alteration.
- The cell surface is mechanosensitive, responding to microenvironmental cues and cytoskeletal dynamics.
- PM topography changes initiate mechanical signaling pathways that interact with molecular signaling to remodel the cell cortex.
Purpose of the Study:
- To review the causes and effects of PM topography changes.
- To highlight the role of PM curvature in actin network induction.
- To connect PM topography dynamics with cell shape regulation.
Main Methods:
- Review of experimental studies on PM topography manipulation.
- Analysis of diverse cell shape change models (e.g., neutrophil migration, embryo cleavage, stem cell division).
- Integration of findings on mechanical signaling and actin dynamics.
Main Results:
- Local PM curvature is sufficient to induce Arp2/3 actin network formation.
- PM topography remodeling is linked to Arp2/3 actin network induction across various cell types.
- PM topography changes are influenced by external structures and internal cytoskeletal forces.
Conclusions:
- Local plasma membrane folding and flattening are key mechanosensitive events.
- Arp2/3 actin network induction is a downstream effect of PM curvature.
- Understanding PM topography dynamics is essential for comprehending cell structure and function.
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