6D9H image
Entry Detail
PDB ID:
6D9H
EMDB ID:
Title:
Cryo-EM structure of the human adenosine A1 receptor-Gi2-protein complex bound to its endogenous agonist
Biological Source:
Source Organism:
Host Organism:
PDB Version:
Deposition Date:
2018-04-29
Release Date:
2018-06-20
Method Details:
Experimental Method:
Resolution:
3.60 Å
Aggregation State:
PARTICLE
Reconstruction Method:
SINGLE PARTICLE
Macromolecular Entities
Polymer Type:polypeptide(L)
Description:Guanine nucleotide-binding protein G(i) subunit alpha-2
Chain IDs:A
Chain Length:355
Number of Molecules:1
Biological Source:Homo sapiens
Polymer Type:polypeptide(L)
Description:Guanine nucleotide-binding protein G(I)/G(S)/G(T) subunit beta-1
Chain IDs:B
Chain Length:350
Number of Molecules:1
Biological Source:Homo sapiens
Polymer Type:polypeptide(L)
Description:Guanine nucleotide-binding protein G(I)/G(S)/G(O) subunit gamma-2
Chain IDs:C (auth: G)
Chain Length:71
Number of Molecules:1
Biological Source:Homo sapiens
Polymer Type:polypeptide(L)
Description:Chimera protein of Muscarinic acetylcholine receptor M4 and Adenosine receptor A1
Chain IDs:D (auth: R)
Chain Length:389
Number of Molecules:1
Biological Source:Homo sapiens
Ligand Molecules
Primary Citation

Abstact

The class A adenosine A1 receptor (A1R) is a G-protein-coupled receptor that preferentially couples to inhibitory Gi/o heterotrimeric G proteins, has been implicated in numerous diseases, yet remains poorly targeted. Here we report the 3.6 Å structure of the human A1R in complex with adenosine and heterotrimeric Gi2 protein determined by Volta phase plate cryo-electron microscopy. Compared to inactive A1R, there is contraction at the extracellular surface in the orthosteric binding site mediated via movement of transmembrane domains 1 and 2. At the intracellular surface, the G protein engages the A1R primarily via amino acids in the C terminus of the Gαi α5-helix, concomitant with a 10.5 Å outward movement of the A1R transmembrane domain 6. Comparison with the agonist-bound β2 adrenergic receptor-Gs-protein complex reveals distinct orientations for each G-protein subtype upon engagement with its receptor. This active A1R structure provides molecular insights into receptor and G-protein selectivity.

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Primary Citation of related structures