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Cross-talk between Rac and Rap GTPases in migrating cells
Ricarda Lüttig1,2, Suchet Nanda1,2, Haritha T Chandran1,2
1Faculty of Chemistry and Chemical Biology, TU Dortmund, Dortmund, Germany 44227.
Molecular Biology of the Cell
|August 6, 2025
Summary
Rap GTPase activates Rac GTPase, coordinating cell protrusion and attachment for effective cell migration. This unidirectional crosstalk mechanism highlights Rap
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Cell migration requires coordinated cell protrusion and attachment.
- Small GTPases Rac and Rap are key regulators of these processes.
Purpose of the Study:
- Investigate spatio-temporal activity patterns of Rac and Rap in migrating cells.
- Elucidate the crosstalk between Rap and Rac in regulating cell protrusion and adhesion.
Main Methods:
- Live-cell imaging of spatio-temporal activity patterns.
- Light-based perturbation methods to analyze crosstalk.
- Rap1 depletion experiments in A431 cells.
Main Results:
- Rac activity tightly correlates with cell protrusion events.
- Rap activity precedes and follows protrusion, remaining elevated.
- Rap activates Rac, but not vice versa.
- Rap1 depletion reduces cell attachment.
Conclusions:
- Rap plays an instructive role in cell protrusion by activating Rac.
- Prolonged Rap activity may stabilize protrusions.
- Rap-stimulated cell adhesion stabilizes newly formed protrusions.
- A unidirectional crosstalk mechanism couples cell protrusion and adhesion via Rap and Rac.
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