N-glycosylation in the protease domain of trypsin-like serine proteases mediates calnexin-assisted protein folding

  1. Hao Wang
  2. Shuo Li
  3. Juejin Wang
  4. Shenghan Chen
  5. Xue-Long Sun
  6. Qingyu Wu  Is a corresponding author
  1. Cleveland Clinic, United States

Abstract

Trypsin-like serine proteases are essential in physiological processes. Studies have shown that N-glycans are important for serine protease expression and secretion, but the underlying mechanisms are poorly understood. Here we report a common mechanism of N-glycosylation in the protease domains of corin, enteropeptidase and prothrombin in calnexin-mediated glycoprotein folding and extracellular expression. This mechanism, which is independent of calreticulin and operates in a domain-autonomous manner, involves two steps: direct calnexin binding to target proteins and subsequent calnexin binding to monoglucosylated N-glycans. Elimination of N-glycosylation sites in the protease domains of corin, enteropeptidase and prothrombin inhibits corin and enteropeptidase cell surface expression and prothrombin secretion in transfected HEK293 cells. Similarly, knocking down calnexin expression in cultured cardiomyocytes and hepatocytes reduced corin cell surface expression and prothrombin secretion, respectively. Our results suggest that this may be a general mechanism in the trypsin-like serine proteases with N-glycosylation sites in their protease domains.

Data availability

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

Article and author information

Author details

  1. Hao Wang

    Department of Molecular Cardiology, Cleveland Clinic, Cleveland, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-6881-9977
  2. Shuo Li

    Department of Molecular Cardiology, Cleveland Clinic, Cleveland, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Juejin Wang

    Department of Molecular Cardiology, Cleveland Clinic, Cleveland, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Shenghan Chen

    Department of Molecular Cardiology, Cleveland Clinic, Cleveland, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Xue-Long Sun

    Department of Molecular Cardiology, Cleveland Clinic, Cleveland, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-6483-1709
  6. Qingyu Wu

    Department of Molecular Cardiology, Cleveland Clinic, Cleveland, United States
    For correspondence
    wuq@ccf.org
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0561-9315

Funding

National Institutes of Health (HL126697)

  • Qingyu Wu

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

Reviewing Editor

  1. Charles S Craik, University of California, San Francisco, United States

Publication history

  1. Received: February 5, 2018
  2. Accepted: June 8, 2018
  3. Accepted Manuscript published: June 11, 2018 (version 1)
  4. Version of Record published: June 27, 2018 (version 2)
  5. Version of Record updated: June 28, 2018 (version 3)

Copyright

© 2018, Wang 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. Hao Wang
  2. Shuo Li
  3. Juejin Wang
  4. Shenghan Chen
  5. Xue-Long Sun
  6. Qingyu Wu
(2018)
N-glycosylation in the protease domain of trypsin-like serine proteases mediates calnexin-assisted protein folding
eLife 7:e35672.
https://doi.org/10.7554/eLife.35672
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