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Updated: Jan 13, 2026
08:21
Monitoring GPCR-β-arrestin1/2 Interactions in Real Time Living Systems to Accelerate Drug Discovery
Published on: June 28, 2019
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Intrinsic conformational equilibria position arrestin-2 for activation.
Tucker J Shriver1, Kerem Kahraman1, Mingzhe Pan2
1Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
Biorxiv : the Preprint Server for Biology
|January 9, 2026
Summary
Arrestin-2 intrinsically samples activation-ready states before binding partners. This research defines the solution-state equilibria governing arrestin pre-activation and signaling competence.
Area of Science:
- Biochemistry
- Molecular Biology
- Structural Biology
Background:
- Arrestins regulate G protein-coupled receptor (GPCR) signaling through conformational changes.
- The solution-state equilibria governing arrestin pre-activation are not well understood.
Purpose of the Study:
- To characterize the intrinsic conformational landscape of full-length human arrestin-2 in solution.
- To define the solution-state equilibria underlying arrestin pre-activation.
Main Methods:
- Methyl-specific nuclear magnetic resonance (NMR) spectroscopy.
- Temperature-dependent chemical shift analysis.
- Relaxation measurements.
Main Results:
- Identified two distinct equilibria with separable thermodynamic and kinetic signatures.
- A slow, enthalpically-favored process populates an active-like conformation at physiological temperatures.
- A faster equilibrium involves C-terminal tail release with opposing thermodynamic behavior.
Conclusions:
- Arrestin-2 intrinsically samples activation-relevant conformations without binding partners.
- Provides a solution-state framework for arrestin pre-activation and signaling competence.
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