Abstract

Members of the nuclear receptor (NR) superfamily regulate both physiological and pathophysiological processes ranging from development and metabolism to inflammation and cancer. Synthetic small molecules targeting NRs are often deployed as therapeutics to correct aberrant NR signaling or as chemical probes to explore the role of the receptor in physiology. Nearly half of NRs do not have specific cognate ligands (termed orphan NRs) and it's unclear if they possess ligand dependent activities. Here we demonstrate that ligand-dependent action of the orphan RORγ can be defined by selectively disrupting putative endogenous-but not synthetic-ligand binding. Furthermore, the characterization of a library of RORγ modulators reveals that structural dynamics of the receptor assessed by HDX-MS correlate with activity in biochemical and cell-based assays. These findings, corroborated with X-ray co-crystallography and site-directed mutagenesis, collectively reveal the structural determinants of RORγ activation, which is critical for designing RORγ agonists for cancer immunotherapy.

Data availability

Due to their large size, all the raw data from MS analysis is available from the authors. HDX Workbench outputs files have been uploaded to figshare (10.6084/m9.figshare.8230685) along with a treated data summary which summarizes the findings from the raw data.

The following data sets were generated

Article and author information

Author details

  1. Timothy S Strutzenberg

    Department of Molecular Medicine, The Scripps Research Institute, Jupiter, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0598-534X
  2. Ruben D Garcia-Ordonez

    Department of Molecular Medicine, The Scripps Research Institute, Jupiter, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Scott J Novick

    Department of Molecular Medicine, The Scripps Research Institute, Jupiter, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. HaJeung Park

    Department of Molecular Medicine, The Scripps Research Institute, Jupiter, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Mi Ra Chang

    Department of Molecular Medicine, The Scripps Research Institute, Jupiter, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Christelle Doebellin

    Department of Molecular Medicine, The Scripps Research Institute, Jupiter, United States
    Competing interests
    The authors declare that no competing interests exist.
  7. Yuanjun He

    Department of Molecular Medicine, The Scripps Research Institute, Jupiter, United States
    Competing interests
    The authors declare that no competing interests exist.
  8. Rémi Patouret

    Department of Molecular Medicine, The Scripps Research Institute, Jupiter, United States
    Competing interests
    The authors declare that no competing interests exist.
  9. Theodore M Kamenecka

    Department of Molecular Medicine, The Scripps Research Institute, Jupiter, United States
    Competing interests
    The authors declare that no competing interests exist.
  10. Patrick R Griffin

    Department of Molecular Medicine, The Scripps Research Institute, Jupiter, United States
    For correspondence
    pgriffin@scripps.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3404-690X

Funding

National Cancer Institute

  • Patrick R Griffin

National Institute of General Medical Sciences

  • Timothy S Strutzenberg

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

Copyright

© 2019, Strutzenberg 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. Timothy S Strutzenberg
  2. Ruben D Garcia-Ordonez
  3. Scott J Novick
  4. HaJeung Park
  5. Mi Ra Chang
  6. Christelle Doebellin
  7. Yuanjun He
  8. Rémi Patouret
  9. Theodore M Kamenecka
  10. Patrick R Griffin
(2019)
HDX-MS reveals structural determinants for RORγ hyperactivation by synthetic agonists
eLife 8:e47172.
https://doi.org/10.7554/eLife.47172

Share this article

https://doi.org/10.7554/eLife.47172

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