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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
Theme and variations on kinetics of GPCR activation/deactivation
1Laboratory for GPCR Biology, Department of Pharmacology and Chemical Biology, University of Pittsburgh, School of Medicine, Pittsburgh, PA 15261, USA. jpv@pitt.edu
Journal of Receptor and Signal Transduction Research
|September 15, 2010
Summary
G protein-coupled receptors (GPCRs) initiate cell signaling pathways. This review examines the kinetics and rate-limiting steps in GPCR signal propagation using live-cell Förster resonance energy transfer (FRET) methods.
Area of Science:
- Cellular Biology
- Biochemistry
- Pharmacology
Background:
- G protein-coupled receptors (GPCRs) are crucial cell surface proteins mediating responses to diverse extracellular signals.
- GPCRs activate intracellular pathways, influencing physiological processes and serving as targets for numerous drugs.
- Signal transduction involves complex ligand-receptor-G protein interactions and conformational changes.
Purpose of the Study:
- To review the kinetic characteristics of GPCR-mediated signal propagation.
- To identify rate-limiting reactions in signaling pathways initiated by GPCRs.
- To discuss findings from live-cell Förster resonance energy transfer (FRET) studies.
Main Methods:
- Literature review focusing on GPCR signaling kinetics.
- Analysis of data from Förster resonance energy transfer (FRET) experiments in live cells.
- Examination of diverse signaling systems including neurotransmitter and hormonal pathways.
Main Results:
- Signal propagation involves sequential, reversible reactions at the plasma membrane.
- Dynamic interactions and protein conformational changes are key to signal transduction.
- FRET studies provide insights into the real-time kinetics of GPCR signaling.
Conclusions:
- Understanding GPCR signaling kinetics is vital for pharmacology and cell biology.
- Rate-limiting steps in GPCR pathways can be elucidated through kinetic analysis.
- Live-cell FRET is a powerful technique for studying dynamic receptor-mediated signaling.
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