Homo-oligomerization of the human adenosine A2a receptor is driven by the intrinsically disordered C-terminus

  1. Khanh Dinh Quoc Nguyen
  2. Michael Vigers
  3. Eric Sefah
  4. Susanna Seppälä
  5. Jennifer Paige Hoover
  6. Nicole Star Schonenbach
  7. Blake Mertz
  8. Michelle Ann O'Malley  Is a corresponding author
  9. Songi Han  Is a corresponding author
  1. University of California - Santa Barbaba, United States
  2. West Virginia University, United States
  3. University of California Santa Barbara, United States

Abstract

G protein-coupled receptors (GPCRs) have long been shown to exist as oligomers with functional properties distinct from those of the monomeric counterparts, but the driving factors of oligomerization remain relatively unexplored. Herein, we focus on the human adenosine A2A receptor (A2AR), a model GPCR that forms oligomers both in vitro and in vivo. Combining experimental and computational approaches, we discover that the intrinsically disordered C-terminus of A2AR drives receptor homo-oligomerization. The formation of A2AR oligomers declines progressively with the shortening of the C-terminus. Multiple interaction types are responsible for A2AR oligomerization, including disulfide linkages, hydrogen bonds, electrostatic interactions, and hydrophobic interactions. These interactions are enhanced by depletion interactions, giving rise to a tunable network of bonds that allow A2AR oligomers to adopt multiple interfaces. This study uncovers the disordered C-terminus as a prominent driving factor for the oligomerization of a GPCR, offering important insight into the effect of C-terminus modification on receptor oligomerization of A2AR and other GPCRs reconstituted in vitro for biophysical studies.

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All data generated or analysed during this study are included in the manuscript and supporting files.

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Author details

  1. Khanh Dinh Quoc Nguyen

    Chemistry and Biochemistry, University of California - Santa Barbaba, Santa Barbara, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9367-499X
  2. Michael Vigers

    Chemistry and Biochemistry, University of California - Santa Barbaba, Santa Barbara, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Eric Sefah

    C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Susanna Seppälä

    Chemical Engineering, University of California - Santa Barbaba, Santa Barbara, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Jennifer Paige Hoover

    Chemistry and Biochemistry, University of California - Santa Barbaba, Santa Barbara, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Nicole Star Schonenbach

    Chemistry and Biochemistry, University of California - Santa Barbaba, Santa Barbara, United States
    Competing interests
    The authors declare that no competing interests exist.
  7. Blake Mertz

    C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, United States
    Competing interests
    The authors declare that no competing interests exist.
  8. Michelle Ann O'Malley

    Chemical Engineering, University of California - Santa Barbaba, Santa Barbara, United States
    For correspondence
    momalley@engineering.ucsb.edu
    Competing interests
    The authors declare that no competing interests exist.
  9. Songi Han

    Department of Chemistry and Biochemistry, Department of Chemical Engineering, University of California Santa Barbara, Santa Barbara, United States
    For correspondence
    songi@chem.ucsb.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-6489-6246

Funding

National Institute of General Medical Sciences (R35GM136411)

  • Khanh Dinh Quoc Nguyen
  • Michael Vigers
  • Susanna Seppälä
  • Nicole Star Schonenbach
  • Michelle Ann O'Malley
  • Songi Han

National Institute of Mental Health (Small Business Innovation Research Award,1R43MH119906-01)

  • Khanh Dinh Quoc Nguyen
  • Jennifer Paige Hoover
  • Michelle Ann O'Malley
  • Songi Han

National Science Foundation (MCB-1714888)

  • Eric Sefah
  • Blake Mertz

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

Reviewing Editor

  1. Heedeok Hong, Michigan State University, United States

Publication history

  1. Preprint posted: December 22, 2020 (view preprint)
  2. Received: January 18, 2021
  3. Accepted: July 15, 2021
  4. Accepted Manuscript published: July 16, 2021 (version 1)
  5. Version of Record published: August 2, 2021 (version 2)

Copyright

© 2021, Nguyen 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. Khanh Dinh Quoc Nguyen
  2. Michael Vigers
  3. Eric Sefah
  4. Susanna Seppälä
  5. Jennifer Paige Hoover
  6. Nicole Star Schonenbach
  7. Blake Mertz
  8. Michelle Ann O'Malley
  9. Songi Han
(2021)
Homo-oligomerization of the human adenosine A2a receptor is driven by the intrinsically disordered C-terminus
eLife 10:e66662.
https://doi.org/10.7554/eLife.66662

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