Related Experiment Video
Updated: Jul 28, 2025
10:59
Visualizing the Conformational Dynamics of Membrane Receptors Using Single-Molecule FRET
Published on: August 17, 2022
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Concerted conformational changes control metabotropic glutamate receptor activity
Nathalie Lecat-Guillet1, Robert B Quast2, Hongkang Liu1,3
1Institut de Génomique Fonctionnelle, Univ. Montpellier, CNRS, INSERM, 141 rue de la Cardonille, 34094, Montpellier Cedex 05, France.
Science Advances
|June 2, 2023
Summary
Allosteric modulators fine-tune neurotransmitter action by controlling metabotropic glutamate (mGlu) receptor activity. These ligands stabilize the fully active dimer conformation of mGlu2 receptors, crucial for brain function.
Area of Science:
- Neuroscience
- Biochemistry
- Molecular Biology
Background:
- Metabotropic glutamate (mGlu) receptors are key regulators of neurotransmission and implicated in brain disorders.
- Allosteric modulators offer precise control over receptor activity by interacting with distinct sites.
- Understanding ligand-induced conformational changes is vital for drug development.
Purpose of the Study:
- To investigate the single-molecule conformational dynamics of full-length mGlu2 receptors upon orthosteric and allosteric ligand binding.
- To elucidate the synergistic roles of orthosteric and allosteric ligands in modulating receptor activity.
Main Methods:
- Development of Förster Resonance Energy Transfer (FRET) sensors using genetic code expansion and click chemistry for live-cell monitoring.
- Application of single-molecule FRET to analyze conformational changes in mGlu2 receptors.
Main Results:
- Orthosteric agonist binding partially stabilizes the closed state of glutamate binding domains but does not fully reorient the dimer to the active state.
- Allosteric modulators binding to the transmembrane domain are essential for stabilizing the fully reoriented, active dimer conformation.
- Concerted conformational changes within the multidomain dimeric GPCR are critical for its function.
Conclusions:
- Allosteric modulators play a crucial role in achieving the fully active conformation of mGlu2 receptors.
- The study provides insights into how multidomain protein conformational dynamics are controlled and modulated by ligands.
- Findings highlight the therapeutic potential of allosteric modulators for brain diseases linked to mGlu receptors.
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