Molecular mechanism of allosteric modulation at GPCRs: insight from a binding kinetics study at the human A1 adenosine receptor.

Background And Purpose: Many GPCRs can be allosterically modulated by small-molecule ligands. This modulation is best understood in terms of the kinetics of the ligand-receptor interaction. However, many current kinetic assays require at least the (radio)labelling of the orthosteric ligand, which is impractical for studying a range of ligands.