1. Biochemistry and Chemical Biology
  2. Structural Biology and Molecular Biophysics

Cryo-EM structure of the adenosine A2A receptor coupled to an engineered heterotrimeric G protein

  1. Javier García-Nafría
  2. Yang Lee
  3. Xiaochen Bai
  4. Byron Carpenter
  5. Christopher G Tate  Is a corresponding author
  1. MRC Laboratory of Molecular Biology, United Kingdom
https://doi.org/10.7554/eLife.35946
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  1. Javier García-Nafría
  2. Yang Lee
  3. Xiaochen Bai
  4. Byron Carpenter
  5. Christopher G Tate
(2018)
Cryo-EM structure of the adenosine A2A receptor coupled to an engineered heterotrimeric G protein
eLife 7:e35946.
https://doi.org/10.7554/eLife.35946
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Abstract

The adenosine A2A receptor (A2AR) is a prototypical G protein-coupled receptor (GPCR) that couples to the heterotrimeric G protein GS. Here we determine the structure by electron cryo-microscopy (cryo-EM) of A2AR at pH 7.5 bound to the small molecule agonist NECA and coupled to an engineered heterotrimeric G protein, which contains mini-GS, the βγ subunits and nanobody Nb35. Most regions of the complex have a resolution of ~3.8 Å or better. Comparison with the 3.4 Å resolution crystal structure shows that the receptor and mini-GS are virtually identical and that the density of the side chains and ligand are of comparable quality. However, the cryo-EM density map also indicates regions that are flexible in comparison to the crystal structures, which unexpectedly includes regions in the ligand binding pocket. In addition, an interaction between intracellular loop 1 of the receptor and the β subunit of the G protein was observed.

Data availability

Structural data have been deposited in the PDB under the accession code 6gdg and in EMDB with accession code 4390

The following data sets were generated
The following previously published data sets were used

Article and author information

Author details

  1. Javier García-Nafría

    Structural Studies, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
    Competing interests
    No competing interests declared.

  2. Yang Lee

    Structural Studies, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
    Competing interests
    No competing interests declared.

  3. Xiaochen Bai

    Structural Studies, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
    Competing interests
    No competing interests declared.

  4. Byron Carpenter

    Structural Studies, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1712-3528

  5. Christopher G Tate

    Structural Studies, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
    For correspondence
    cgt@mrc-lmb.cam.ac.uk
    Competing interests
    Christopher G Tate, is a consultant and shareholder of Heptares Therapeutics, and they also funded this work.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2008-9183

Funding

Medical Research Council (U105197215)

  • Christopher G Tate

European Research Council (EMPSI 339995)

  • Christopher G Tate

Heptares Therapeutics (n/a)

  • Christopher G Tate

Pfizer UK (n/a)

  • Christopher G Tate

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Copyright

© 2018, García-Nafría et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Javier García-Nafría
  2. Yang Lee
  3. Xiaochen Bai
  4. Byron Carpenter
  5. Christopher G Tate
(2018)
Cryo-EM structure of the adenosine A2A receptor coupled to an engineered heterotrimeric G protein
eLife 7:e35946.
https://doi.org/10.7554/eLife.35946

Share this article

https://doi.org/10.7554/eLife.35946

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