Ligand modulation of the conformational dynamics of the A2A adenosine receptor revealed by single-molecule fluorescence oleh Dennis D. Fernandes, Chris Neale, Gregory-Neal W. Gomes, Yuchong Li, Aimen Malik, Aditya Pandey, Alexander P. Orazietti, Xudong Wang, Libin Ye, R. Scott Prosser, Claudiu C. Gradinaru