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Updated: Jun 25, 2026

Affinity Precipitation of Active Rho-GEFs Using a GST-tagged Mutant Rho Protein (GST-RhoA(G17A)) from Epithelial Cell Lysates
Published on: March 31, 2012
Regulation of RhoGEF proteins by G12/13-coupled receptors.
1Novartis Institutes for BioMedical Research Basel, Center for Proteomic Chemistry, Novartis Pharma AG, Basel, Switzerland. sandra.siehler@novartis.com
G protein-coupled receptors (GPCRs) signal through G proteins. This review focuses on G(12/13) pathways, highlighting RhoGEF proteins and their role in diseases like cancer and cardiovascular conditions.
Area of Science:
- Cellular signaling pathways
- Molecular biology
- Pharmacology
Background:
- G protein-coupled receptors (GPCRs) are crucial for cellular communication, with over 700 types in the human genome.
- GPCR signaling diversity arises from tissue expression, subcellular localization, and G protein coupling (G(s), G(i), G(q), G(12)).
- G(12/13) signaling, a less-studied pathway, links GPCRs to Rho GTPase nucleotide exchange factors (RhoGEFs).
Purpose of the Study:
- To review the role of G(12/13) signaling in GPCR pathways.
- To highlight the function of RhoGEF proteins as key mediators in G(12/13) activation.
- To discuss the implications of G(12/13) signaling in various pathophysiological conditions and therapeutic strategies.
Main Methods:
- Literature review focusing on G(12/13) signaling mechanisms.
- Analysis of the known mammalian RhoGEFs regulated by G(12/13) proteins.
- Discussion of emerging assays for measuring GPCR-mediated G(12/13) activation.
Main Results:
- Four mammalian RhoGEFs (p115-RhoGEF, PDZ-RhoGEF, LARG, and GEF-H1) are identified as direct mediators of G(12/13) signaling.
- These RhoGEFs link activated GPCRs to the RhoA GTPase pathway, influencing cellular processes.
- Dysregulated G(12/13) signaling is implicated in cancer, cardiovascular diseases, hypertension, and asthma.
Conclusions:
- G(12/13) signaling, mediated by RhoGEFs, represents a significant pathway for GPCRs with implications in numerous diseases.
- Targeting G(12/13) pathways offers novel therapeutic opportunities for conditions linked to GPCR dysregulation.
- Further development of assays is crucial for understanding G(12/13)-GPCR pharmacology and advancing therapeutic interventions.
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