Fig. 1: Structural snapshots of MOR along the initial steps of the G protein activation pathway.
From: Structural snapshots capture nucleotide release at the μ-opioid receptor
a, Overview of cryoEM reconstructions of MOR and MOR–Gαi1 complexes in complex with naloxone or loperamide in six conformational states, with or without GDPβS present: (1) inactive, (2) latent, (3) engaged, (4) unlatched, (5) primed and (6) nucleotide-free. b,c, Corresponding densities of GDPβS in G protein structures. b, Naloxone: latent, unlatched, primed. c, Loperamide: engaged, unlatched, primed. d, Naloxone in the orthosteric binding pocket across latent and primed states, with interacting residues highlighted in stick representation. e, Overlay of ligands in the orthosteric binding pocket. Naloxone across latent and primed structures, highlighting ligand pose; ‘shallow’ versus ‘deep’. Light green, latent; orange, primed. Loperamide across engaged and primed structures: yellow, engaged; orange, primed. f, Loperamide in the orthosteric binding pocket across engaged and primed state, with interacting residues highlighted in stick representation. wt, wild type.
