Regulation of pulmonary surfactant by the adhesion GPCR GPR116/ADGRF5 requires a tethered agonist-mediated activation mechanism

  1. James P Bridges
  2. Caterina Safina
  3. Bernard Pirard
  4. Kari Brown
  5. Alyssa Filuta
  6. Ravichandran Panchanathan
  7. Rochdi Bouhelal
  8. Nicole Reymann
  9. Sejal Patel
  10. Klaus Seuwen
  11. William E Miller
  12. Marie-Gabrielle Ludwig  Is a corresponding author
  1. Cincinnati Children's Hospital Medical Center, United States
  2. Novartis, Switzerland
  3. University of Cincinnati, United States
  4. Novartis, United States

Abstract

The mechanistic details of the tethered agonist mode of activation for the adhesion GPCR ADGRF5/GPR116 has not been completely deciphered. We set out to investigate the physiologic importance of autocatalytic cleavage upstream of the agonistic peptide sequence, an event necessary for NTF displacement and subsequent receptor activation. To examine this hypothesis, we characterized tethered agonist-mediated activation of GPR116 in vitro and in vivo. A knock-in mouse expressing a non-cleavable GPR116 mutant phenocopies the pulmonary phenotype of GPR116 knock-out mice, demonstrating that tethered agonist-mediated receptor activation is indispensable for function in vivo. Using site-directed mutagenesis and species swapping approaches we identified key conserved amino acids for GPR116 activation in the tethered agonist sequence and in extracellular loops 2/3 (ECL2/3). We further highlight residues in transmembrane7 (TM7) that mediate stronger signaling in mouse versus human GPR116 and recapitulate these findings in a model supporting tethered agonist:ECL2 interactions for GPR116 activation.

Data availability

Source data for the modeling is provided (coordinates of the model)

Article and author information

Author details

  1. James P Bridges

    Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, United States
    Competing interests
    No competing interests declared.
  2. Caterina Safina

    Novartis Institutes for Biomedical Research, Novartis, Basel, Switzerland
    Competing interests
    Caterina Safina, is employed by and shareholder of Novartis Pharma AG..
  3. Bernard Pirard

    Novartis Institutes for Biomedical Research, Novartis, Basel, Switzerland
    Competing interests
    Bernard Pirard, is employed by and shareholder of Novartis Pharma AG..
  4. Kari Brown

    Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, United States
    Competing interests
    No competing interests declared.
  5. Alyssa Filuta

    Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, United States
    Competing interests
    No competing interests declared.
  6. Ravichandran Panchanathan

    Department of Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati, Cincinnati, United States
    Competing interests
    No competing interests declared.
  7. Rochdi Bouhelal

    Novartis Institutes for Biomedical Research, Novartis, Basel, Switzerland
    Competing interests
    Rochdi Bouhelal, is employed by and shareholder of Novartis Pharma AG..
  8. Nicole Reymann

    Novartis Institutes for Biomedical Research, Novartis, Basel, Switzerland
    Competing interests
    Nicole Reymann, is employed by and shareholders of Novartis Pharma AG.
  9. Sejal Patel

    Novartis Institutes for Biomedical Research, Novartis, Cambridge, United States
    Competing interests
    Sejal Patel, is employed by and shareholder of Novartis Pharma AG..
  10. Klaus Seuwen

    Novartis Institutes for Biomedical Research, Novartis, Basel, Switzerland
    Competing interests
    Klaus Seuwen, is employed by and shareholder of Novartis Pharma AG..
  11. William E Miller

    Department of Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati, Cincinnati, United States
    Competing interests
    No competing interests declared.
  12. Marie-Gabrielle Ludwig

    Novartis Institutes for Biomedical Research, Novartis, Basel, Switzerland
    For correspondence
    marie-gabrielle.ludwig@novartis.com
    Competing interests
    Marie-Gabrielle Ludwig, is employed by and shareholder of Novartis Pharma AG..
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7799-4782

Funding

National Heart, Lung and Blood Institute of the NIH (HL131634)

  • Caterina Safina
  • Bernard Pirard

This work was funded in part by the NIH grant listed above.

Ethics

Animal experimentation: All animal procedures were performed under protocols (AS2842_05_22; JPB) approved by the Institutional Animal Care and Use Committee of National Jewish Health in accordance with National Institutes of Health guidelines.

Reviewing Editor

  1. Demet Araç, University of Chicago, United States

Publication history

  1. Preprint posted: April 2, 2021 (view preprint)
  2. Received: April 2, 2021
  3. Accepted: September 7, 2022
  4. Accepted Manuscript published: September 8, 2022 (version 1)
  5. Version of Record published: September 20, 2022 (version 2)

Copyright

© 2022, Bridges 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. James P Bridges
  2. Caterina Safina
  3. Bernard Pirard
  4. Kari Brown
  5. Alyssa Filuta
  6. Ravichandran Panchanathan
  7. Rochdi Bouhelal
  8. Nicole Reymann
  9. Sejal Patel
  10. Klaus Seuwen
  11. William E Miller
  12. Marie-Gabrielle Ludwig
(2022)
Regulation of pulmonary surfactant by the adhesion GPCR GPR116/ADGRF5 requires a tethered agonist-mediated activation mechanism
eLife 11:e69061.
https://doi.org/10.7554/eLife.69061

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