Very little is known about how a G-protein-coupled receptor (GPCR) transitions from an inactive to an active state, but this study has solved the X-ray crystal structures of the human M2 muscarinic acetylcholine receptor bound to a high-affinity agonist in an active state and to a high-affinity agonist and a small-molecule allosteric modulator in an active state; the structures provide insights into the activation mechanism and allosteric modulation of muscarinic receptors.
- Andrew C. Kruse
- Aaron M. Ring
- Brian K. Kobilka