3DQB

Crystal structure of the active G-protein-coupled receptor opsin in complex with a C-terminal peptide derived from the Galpha subunit of transducin

Summary for 3DQB

• Entry DOI: 10.2210/pdb3dqb/pdb
• Descriptor: Rhodopsin, 11meric peptide form Guanine nucleotide-binding protein G(t) subunit alpha-1, alpha-D-mannopyranose-(1-3)-beta-D-mannopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose, ... (7 entities in total)
• Functional Keywords: protein, retinal protein, photoreceptor, ligand-free state, chromophore, g-protein coupled receptor, glycoprotein, lipoprotein, palmitate, phosphoprotein, photoreceptor protein, sensory transduction, transducer, transmembrane, vision, signaling protein, g-protein, transducin, galpha subunit, membrane, receptor, gtp-binding, myristate, nucleotide-binding, g-protein-coupled receptor, rhodopsin, opsin
• Biological source: Bos taurus (Bovine); More
• Total number of polymer chains: 2
• Total formula weight: 42859.99

Authors

Scheerer, P.,Park, J.H.,Hildebrand, P.W.,Kim, Y.J.,Krauss, N.,Choe, H.-W.,Hofmann, K.P.,Ernst, O.P. (deposition date: 2008-07-09, release date: 2008-09-23, Last modification date: 2024-11-06)

Primary citation

Scheerer, P.,Park, J.H.,Hildebrand, P.W.,Kim, Y.J.,Krauss, N.,Choe, H.-W.,Hofmann, K.P.,Ernst, O.P.
Crystal structure of opsin in its G-protein-interacting conformation
Nature, 455:497-502, 2008

PubMed Abstract: Opsin, the ligand-free form of the G-protein-coupled receptor rhodopsin, at low pH adopts a conformationally distinct, active G-protein-binding state known as Ops*. A synthetic peptide derived from the main binding site of the heterotrimeric G protein-the carboxy terminus of the alpha-subunit (GalphaCT)-stabilizes Ops*. Here we present the 3.2 A crystal structure of the bovine Ops*-GalphaCT peptide complex. GalphaCT binds to a site in opsin that is opened by an outward tilt of transmembrane helix (TM) 6, a pairing of TM5 and TM6, and a restructured TM7-helix 8 kink. Contacts along the inner surface of TM5 and TM6 induce an alpha-helical conformation in GalphaCT with a C-terminal reverse turn. Main-chain carbonyl groups in the reverse turn constitute the centre of a hydrogen-bonded network, which links the two receptor regions containing the conserved E(D)RY and NPxxY(x)(5,6)F motifs. On the basis of the Ops*-GalphaCT structure and known conformational changes in Galpha, we discuss signal transfer from the receptor to the G protein nucleotide-binding site.

PubMed: 18818650
DOI: 10.1038/nature07330

Experimental method

X-RAY DIFFRACTION (3.2 Å)