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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
Conserved activation pathways in G-protein-coupled receptors
Xavier Deupi1, Jörg Standfuss, Gebhard Schertler
1Laboratory of Biomolecular Research, Paul Scherrer Institut, Villigen PSI, Switzerland.
Structural insights into G-protein-coupled receptors (GPCRs) reveal conserved activation pathways. The structure of active rhodopsin provides a native-like model for understanding GPCR activation mechanisms.
Area of Science:
- Structural Biology
- Biochemistry
- Molecular Pharmacology
Background:
- G-protein-coupled receptors (GPCRs) are crucial cell signaling proteins.
- Understanding GPCR activation mechanisms is vital for physiology and drug discovery.
- Recent advances have provided structural insights into GPCRs.
Purpose of the Study:
- To elucidate the structural basis of GPCR activation.
- To establish a native-like model of an active GPCR.
- To identify conserved activation pathways within GPCRs.
Main Methods:
- Determination of active-like GPCR structures (2008-2011).
- Structural analysis of light-activated rhodopsin (metarhodopsin-II).
- Comparative analysis of inactive, intermediate, and active rhodopsin states.
Main Results:
- The structure of active metarhodopsin-II represents a native-like active GPCR model.
- Rhodopsin structures provide a framework for understanding conserved GPCR activation.
- Three conserved intramolecular activation pathways (TM5/TM3, TM6, TM7/TM2) were identified.
Conclusions:
- Retinal isomerization initiates structural changes leading to GPCR activation.
- Conserved activation pathways suggest common mechanisms across GPCRs.
- Ligand-mediated differential pathway activation can lead to distinct signaling states.
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