Related Experiment Video
Updated: May 2, 2026

Affinity Precipitation of Active Rho-GEFs Using a GST-tagged Mutant Rho Protein GST-RhoAG17A from Epithelial Cell Lysates
Published on: March 31, 2012
Phosphorylation-mediated regulation of GEFs for RhoA
Maulik Patel1, Andrei V Karginov1
1Department of Pharmacology; University of Illinois at Chicago; Chicago, IL USA.
Abstract:
Spatio-temporal control of RhoA GTPase is critical for regulation of cell migration, attachment to extracellular matrix, and cell-cell adhesions. Activation of RhoA is mediated by guanine nucleotide exchange factors (GEFs), a diverse family of enzymes that are controlled by multiple signaling pathways regulating actin cytoskeleton and cell migration. GEFs can be regulated by different mechanisms. Growing evidence demonstrates that phosphorylation serves as one of the predominant signals controlling activity, interactions, and localization of RhoGEFs. It acts as a positive and a negative regulator, and allows for regulation of RhoGEFs by multiple signaling cascades. Although there are common trends in phosphorylation-mediated regulation of some RhoGEF homologs, the majority of GEFs utilize distinct mechanisms that are dictated by their unique structure and interaction networks. This diversity enables multiple signaling pathways to use different RhoGEFs for regulation of a single central-RhoA. Here, we review current examples of phosphorylation-mediated regulation of GEFs for RhoA and its role in cell migration, discuss mechanisms, and provide insights into potential future directions.
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