Abstract
G protein-coupled receptors exist in a whole spectrum of conformations which are stabilised by the binding of ligands with different efficacy or intracellular effector proteins. Here, we investigate whether three-dimensional structures of receptor conformations in different states of activation can be utilised to enrich ligands with agonist behaviour in prospective docking calculations. We focused on the β2-adrenergic receptor, as it currently is the receptor with the highest number of active-state crystal structures. Comparative docking calculations to distinct conformations of the receptor were used for the in silico prediction of ligands with agonist efficacy. The pharmacology of molecules selected based on these predictions was characterised experimentally, resulting in a hit rate of 37% ligands, all of which were agonists. The ligands furthermore contain a pyrazole moiety which has previously not been described for β2 -adrenergic receptor ligands and one of them shows an intrinsic efficacy comparable to salbutamol.
SIGNIFICANCE STATEMENT Structure-based ligand design for G protein-coupled receptors crucially depends on receptor conformation and hence their activation state. We explored the influence of using multiple active-conformation X-ray structures on the hit rate of docking calculations to find novel agonists and how to predict the most fruitful strategy to apply. The results suggest that aggregating the ranks of molecules across docking calculations to more than one active-state structure exclusively yields agonists.
- Adrenergic receptors
- Beta-adrenergic receptors
- Computational drug design
- Drug development
- G protein-coupled receptors (GPCRs)
- High throughput screening
- Ligand docking
- Molecular modeling
- Receptor structure
- The American Society for Pharmacology and Experimental Therapeutics