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Updated: May 27, 2026
15:13
High-resolution Spatiotemporal Analysis of Receptor Dynamics by Single-molecule Fluorescence Microscopy
Published on: July 25, 2014
Real-time G-protein-coupled receptor imaging to understand and quantify receptor dynamics.
María S Aymerich1, J López-Azcárate, J Bonaventura
1Área de Neurociencias, CIMA, Universidad de Navarra, Avenida Pío XII 55, 31008 Pamplona, Spain. maymerich@unav.es
Thescientificworldjournal
|November 30, 2011
Summary
Live imaging of G-protein-coupled receptors (GPCRs) using spinning disk confocal microscopy reveals agonist-induced receptor movement. Receptor internalization is dependent on G protein-coupled receptor kinase 2, showing movement and internalization are not directly coupled.
Area of Science:
- Cell biology
- Pharmacology
- Biophysics
Background:
- Understanding G-protein-coupled receptor (GPCR) trafficking is crucial for drug development.
- Optical methods like spinning disk confocal microscopy offer real-time insights into membrane receptor dynamics.
- Previous methods faced challenges with photobleaching in short-term assays.
Purpose of the Study:
- To develop a photobleaching-corrected image analysis method for studying GPCR dynamics.
- To investigate the short-term and long-term dynamics of the dopamine D2 receptor long isoform.
- To determine the relationship between receptor lateral movement and internalization.
Main Methods:
- Utilizing spinning disk confocal microscopy for fast image acquisition with minimal cell perturbation.
- Developing and applying a photobleaching-corrected image analysis procedure.
- Quantifying receptor dynamics, including mobile fraction and internalization rates.
Main Results:
- An agonist-induced increase in the mobile fraction of dopamine D2 receptors was observed, with a movement rate of 0.08 μm/s.
- Receptor internalization was observed only in cells co-expressing G protein-coupled receptor kinase 2.
- Lateral movement and internalization of GPCRs were found to be independent processes.
Conclusions:
- The developed photobleaching-corrected live imaging method is a powerful tool for studying GPCR dynamics.
- Agonist stimulation enhances GPCR lateral mobility.
- GPCR internalization is regulated by G protein-coupled receptor kinase 2 and is uncoupled from lateral movement.
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