Formation of cell outgrowths by external force: a model study

Area of Science:

• Cell Biology
• Biophysics
• Membrane Dynamics

Background:

• Cell outgrowth formation is crucial for various physiological processes.
• Understanding the mechanisms driving cell membrane protrusions is essential for cell biology research.

Purpose of the Study:

• To investigate cell outgrowth formation induced by an extrinsic force generated by alternating current electric fields (AC EF).
• To explore the role of membrane structure versus cytoskeletal reorganization in generating these protrusions.

Main Methods:

• Application of high-frequency AC EF in a specialized chamber to generate outward force on cell membranes.
• Observation of cell morphology changes in various cell types (mouse embryo fibroblasts, human fibroblasts, mouse L cells, Ehrlich ascites tumor cells, erythrocytes).
• Testing the effect of various inhibitors (cytochalasin B, sodium azide, etc.) and conditions (low temperature) on process generation.

Main Results:

• AC EF successfully induced cell-specific membrane protrusions in fibroblasts and L cells, mimicking normal physiological outgrowths.
• Ehrlich ascites tumor cells formed only thin, short processes, while erythrocytes did not form processes.
• An aligned microfilament system was observed in fibroblast outgrowths, but inhibitors did not prevent EF-induced process generation.

Conclusions:

• Cell protrusion morphology under AC EF is likely determined by plasma membrane domain structure.
• The findings suggest that active cytoskeletal reorganization is not the primary driver of EF-induced cell protrusions.
• The developed experimental system offers a novel approach to study mechanical linkages between the cytoskeleton and plasma membrane.