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A Kinetic Fluorescence-based Ca2+ Mobilization Assay to Identify G Protein-coupled Receptor Agonists, Antagonists, and Allosteric Modulators
Published on: February 20, 2018
G-protein-coupled receptor kinases and the heart
1Martin J. Lohse is at the Laboratory of Molecular Biology, University of Munich, 82152 Martinsried, Germany; the Institute of Pharmacology and Toxicology, University of Würzburg, 97078 Würzburg, Germany.
Trends in Cardiovascular Medicine
|January 15, 2011
Summary
G-protein-coupled receptor kinases (GRKs) phosphorylate receptors, leading to arrestin binding and reduced function. Increased GRK activity, especially in heart failure, impairs beta-adrenergic receptor signaling.
Area of Science:
- Biochemistry
- Molecular Biology
- Cardiology
Background:
- G-protein-coupled receptors (GPCRs) are crucial cell surface receptors involved in numerous physiological processes.
- GPCR regulation is essential for adapting cellular function to environmental changes.
- G-protein-coupled receptor kinases (GRKs) and arrestins mediate receptor desensitization through phosphorylation and uncoupling.
Purpose of the Study:
- To explore the role of GRKs and arrestins in GPCR regulation, particularly in the cardiac context.
- To investigate the involvement of these proteins in drug-induced receptor dysfunction.
- To examine the contribution of GRK activity to heart failure pathophysiology.
Main Methods:
- The study discusses the known mechanisms of GPCR regulation by GRKs and arrestins.
- It reviews the expression of GRK and arrestin isoforms in the heart.
- The text references findings on increased GRK expression in failing hearts.
Main Results:
- Phosphorylation of GPCRs by GRKs leads to arrestin binding and functional uncoupling.
- Multiple GRK and arrestin isoforms are present in the heart.
- Elevated β-adrenergic receptor kinase-1 (βARK1) expression and activity are observed in heart failure.
Conclusions:
- GRKs and arrestins play a significant role in regulating GPCR function in the heart.
- These proteins may contribute to receptor dysfunction induced by pharmacological agents.
- Increased GRK activity, particularly βARK1, is implicated in the loss of β-adrenergic receptor function in heart failure.
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