Geometry-Driven Polarity in Motile Amoeboid Cells

Area of Science:

• Cell biology
• Biophysics
• Mechanobiology

Background:

• Eukaryotic cell motility is crucial for biological processes.
• Confinement significantly alters cell movement compared to planar surfaces.
• Understanding cell behavior in confined spaces is key to biological functions.

Purpose of the Study:

• To investigate the impact of confinement on motile eukaryotic cell behavior.
• To identify the mechanisms behind symmetry breaking in confined cell motility.
• To model the actin cytoskeleton dynamics during confined cell movement.

Main Methods:

• Experimental observation of amoeboid cells in narrow channels.
• Analysis of cell speed, persistence, and leading edge protrusions.
• Characterization of actin cytoskeleton organization using microscopy.
• Development and application of an excitable network model.

Main Results:

• Cells spontaneously break symmetry in confined interstitial spaces.
• A switch to persistent, unidirectional motion along channels was observed.
• Cells maintained contact with opposing walls, alternating leading edge protrusions.
• Actin cytoskeleton showed dense foci at walls and dynamic regions at the leading edge.
• An excitable network model successfully explained confinement-induced symmetry breaking and protrusion patterns.

Conclusions:

• Confinement induces a novel polarity in motile amoeboid cells.
• Geometry-driven polarity is essential for cell movement in interstitial environments.
• The findings provide insights into cell migration in tissues and soil.