1. Structural Biology and Molecular Biophysics

Cryo-EM structure of the lysosomal chloride-proton exchanger CLC-7 in complex with OSTM1

  1. Marina Schrecker
  2. Julia Korobenko
  3. Richard K Hite  Is a corresponding author
  1. Memorial Sloan Kettering Cancer Center, United States
https://doi.org/10.7554/eLife.59555
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  1. Marina Schrecker
  2. Julia Korobenko
  3. Richard K Hite
(2020)
Cryo-EM structure of the lysosomal chloride-proton exchanger CLC-7 in complex with OSTM1
eLife 9:e59555.
https://doi.org/10.7554/eLife.59555
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Abstract

The chloride-proton exchanger CLC-7 plays critical roles in lysosomal homeostasis and bone regeneration and its mutation can lead to osteopetrosis, lysosomal storage disease and neurological disorders. In lysosomes and the ruffled border of osteoclasts, CLC-7 requires a b-subunit, OSTM1, for stability and activity. Here we present electron cryomicroscopy structures of CLC-7 in occluded states by itself and in complex with OSTM1, determined at resolutions up to 2.8 Å. In the complex, the luminal surface of CLC-7 is entirely covered by a dimer of the heavily glycosylated and disulfide-bonded OSTM1, which serves to protect CLC-7 from the degradative environment of the lysosomal lumen. OSTM1 binding does not induce large-scale rearrangements of CLC-7, but does have minor effects the conformation of the ion-conduction pathway, potentially contributing to its regulatory role. These studies provide insights into the role of OSTM1 and serve as a foundation for understanding the mechanisms of CLC-7 regulation.

Data availability

Cryo-EM maps and atomic coordinates have been deposited with the EMDB and PDB under accession codes EMD-22386 and PDB ID 7JM6 for ggCLC-7 and EMD-22389 andPDB ID 7JM7 for human CLC-7/OSTM1. All other reagents are available from the corresponding author upon reasonable request.

The following data sets were generated
The following previously published data sets were used

Article and author information

Author details

  1. Marina Schrecker

    Structural Biology Program, Memorial Sloan Kettering Cancer Center, New York, United States
    Competing interests
    The authors declare that no competing interests exist.

  2. Julia Korobenko

    Structural Biology Program, Memorial Sloan Kettering Cancer Center, New York, United States
    Competing interests
    The authors declare that no competing interests exist.

  3. Richard K Hite

    Structural Biology Program, Memorial Sloan Kettering Cancer Center, New York, United States
    For correspondence
    hiter@mskcc.org
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0496-0669

Funding

Searle Scholars Program

  • Richard K Hite

Josie Robertson Investigators Program

  • Richard K Hite

National Cancer Institute (accessory subunit)

  • Richard K Hite

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

Reviewing Editor

  1. Merritt Maduke, Stanford University School of Medicine, United States

Version history

  1. Received: June 1, 2020
  2. Accepted: July 29, 2020
  3. Accepted Manuscript published: August 4, 2020 (version 1)
  4. Version of Record published: August 20, 2020 (version 2)

Copyright

© 2020, Schrecker 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. Marina Schrecker
  2. Julia Korobenko
  3. Richard K Hite
(2020)
Cryo-EM structure of the lysosomal chloride-proton exchanger CLC-7 in complex with OSTM1
eLife 9:e59555.
https://doi.org/10.7554/eLife.59555

Share this article

https://doi.org/10.7554/eLife.59555

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