1. Sub-millisecond conformational dynamics of the A2A adenosine receptor revealed by single-molecule FRET.
- Author
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Maslov, Ivan, Volkov, Oleksandr, Khorn, Polina, Orekhov, Philipp, Gusach, Anastasiia, Kuzmichev, Pavel, Gerasimov, Andrey, Luginina, Aleksandra, Coucke, Quinten, Bogorodskiy, Andrey, Gordeliy, Valentin, Wanninger, Simon, Barth, Anders, Mishin, Alexey, Hofkens, Johan, Cherezov, Vadim, Gensch, Thomas, Hendrix, Jelle, and Borshchevskiy, Valentin
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FLUORESCENCE resonance energy transfer ,CELL membranes ,G protein coupled receptors - Abstract
The complex pharmacology of G-protein-coupled receptors (GPCRs) is defined by their multi-state conformational dynamics. Single-molecule Förster Resonance Energy Transfer (smFRET) is well suited to quantify dynamics for individual protein molecules; however, its application to GPCRs is challenging. Therefore, smFRET has been limited to studies of inter-receptor interactions in cellular membranes and receptors in detergent environments. Here, we performed smFRET experiments on functionally active human A
2A adenosine receptor (A2A AR) molecules embedded in freely diffusing lipid nanodiscs to study their intramolecular conformational dynamics. We propose a dynamic model of A2A AR activation that involves a slow (>2 ms) exchange between the active-like and inactive-like conformations in both apo and antagonist-bound A2A AR, explaining the receptor's constitutive activity. For the agonist-bound A2A AR, we detected faster (390 ± 80 µs) ligand efficacy-dependent dynamics. Our work establishes a general smFRET platform for GPCR investigations that can potentially be used for drug screening and/or mechanism-of-action studies. Single-molecule FRET experiments with human A2A adenosine receptor in its apo and agonist-bound states in lipid nanodiscs provide insights into its conformational dynamics and activation. [ABSTRACT FROM AUTHOR]- Published
- 2023
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