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Updated: Aug 17, 2026

Comparing the Affinity of GTPase-binding Proteins using Competition Assays
Published on: October 8, 2015
Contraction reaction: mechanical regulation of Rho GTPase
1Abramson Family Cancer Research Institute, BRB II/III, 421 Curie Boulevard, University of Pennsylvania, Philadelphia PA, 19104-6160, USA. molson@mail.med.upenn.edu
Abstract:
Epithelial cell differentiation is influenced by the physical environment. Local external changes in rigidity of the extracellular matrix are 'sensed' as increased or decreased tension and communicated intracellularly. The communications network that signals the state of the extracellular physical environment acts through the actin cytoskeleton to modulate Rho GTPase activity. A recent paper reports the surprising finding that breast epithelial cells respond to flexible surroundings by downregulating Rho activity through the actions of the Rho-regulated ROCK kinases.
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