1. Biochemistry and Chemical Biology
  2. Cell Biology
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An unexpected role for the yeast nucleotide exchange factor Sil1 as a reductant acting on the molecular chaperone BiP

  1. Kevin D Siegenthaler
  2. Kristeen A Pareja
  3. Jie Wang
  4. Carolyn S Sevier  Is a corresponding author
  1. Cornell University, United States
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Cite this article as: eLife 2017;6:e24141 doi: 10.7554/eLife.24141

Abstract

Unfavorable redox conditions in the endoplasmic reticulum (ER) can decrease the capacity for protein secretion, altering vital cell functions. While systems to manage reductive stress are well-established, how cells cope with an overly oxidizing ER remains largely undefined. In previous work (Wang et al., 2014), we demonstrated that the chaperone BiP is a sensor of overly oxidizing ER conditions. We showed that modification of a conserved BiP cysteine during stress beneficially alters BiP chaperone activity to cope with suboptimal folding conditions. How this cysteine is reduced to reestablish 'normal' BiP activity post-oxidative stress has remained unknown. Here we demonstrate that BiP's nucleotide exchange factor – Sil1 – can reverse BiP cysteine oxidation. This previously unexpected reductant capacity for yeast Sil1 has potential implications for the human ataxia Marinesco-Sjögren syndrome, where it is interesting to speculate that a disruption in ER redox-signaling (due to genetic defects in SIL1) may influence disease pathology.

Article and author information

Author details

  1. Kevin D Siegenthaler

    Department of Molecular Medicine, Cornell University, Ithaca, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Kristeen A Pareja

    Department of Molecular Medicine, Cornell University, Ithaca, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Jie Wang

    Department of Molecular Medicine, Cornell University, Ithaca, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Carolyn S Sevier

    Department of Molecular Medicine, Cornell University, Ithaca, United States
    For correspondence
    css224@cornell.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3245-6988

Funding

National Institutes of Health (R01 GM105958)

  • Carolyn S Sevier

National Institutes of Health (T32 GM007273)

  • Kevin D Siegenthaler

National Science Foundation (Graduate Student Fellowship)

  • Kristeen A Pareja

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

Reviewing Editor

  1. David Ron, University of Cambridge, United Kingdom

Publication history

  1. Received: December 12, 2016
  2. Accepted: March 2, 2017
  3. Accepted Manuscript published: March 3, 2017 (version 1)
  4. Version of Record published: March 20, 2017 (version 2)
  5. Version of Record updated: April 4, 2017 (version 3)

Copyright

© 2017, Siegenthaler 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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