Surface changes during retraction-induced spreading of fibroblasts

Area of Science:

• Cell biology
• Cytoskeletal dynamics
• Cell migration

Background:

• Cell migration is crucial for development and disease.
• Understanding the regulation of cell protrusion is key to controlling cell movement.

Purpose of the Study:

• To investigate the effect of trailing edge retraction on cell leading edge activity.
• To elucidate the mechanisms governing cell spreading and protrusion formation.

Main Methods:

• Time-lapse cinemicrography to observe dynamic cell behavior.
• Scanning electron microscopy to visualize cell surface structures.
• Microneedle manipulation to induce controlled retraction.

Main Results:

• Trailing edge retraction caused a significant increase in leading edge protrusion.
• Increased cell spreading was primarily due to a longer extension phase of lamellipodial activity.
• Cell surface exhibited transient folds and microvilli upon retraction, which disappeared upon full spreading.

Conclusions:

• Trailing edge retraction enhances leading edge protrusive activity.
• This phenomenon is linked to the redistribution of surface membrane and cytoplasm.
• The findings support a model where retraction facilitates protrusion formation elsewhere in the cell.