Measuring ligand efficacy at the mu-opioid receptor using a conformational biosensor

@article{Livingston2018MeasuringLE,
  title={Measuring ligand efficacy at the mu-opioid receptor using a conformational biosensor},
  author={Kathryn E. Livingston and Jacob P. Mahoney and Aashish Manglik and Roger K. Sunahara and John R. Traynor},
  journal={eLife},
  year={2018},
  volume={7}
}
The intrinsic efficacy of orthosteric ligands acting at G-protein-coupled receptors (GPCRs) reflects their ability to stabilize active receptor states (R*) and is a major determinant of their physiological effects. Here, we present a direct way to quantify the efficacy of ligands by measuring the binding of a R*-specific biosensor to purified receptor employing interferometry. As an example, we use the mu-opioid receptor (µ-OR), a prototypic class A GPCR, and its active state sensor, nanobody… 

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