1. Biochemistry and Chemical Biology
  2. Cell Biology
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Identification of NPC1 as the target of U18666A, an inhibitor of lysosomal cholesterol export and Ebola infection

  1. Feiran Lu
  2. Qiren Liang
  3. Lina Abi-Mosleh
  4. Akash Das
  5. Jef K De Brabander
  6. Joseph L Goldstein  Is a corresponding author
  7. Michael S Brown
  1. University of Texas Southwestern Medical Center, United States
  2. The University of Texas Southwestern Medical Center, United States
Research Article
  • Cited 128
  • Views 8,445
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Cite this article as: eLife 2015;4:e12177 doi: 10.7554/eLife.12177

Abstract

Niemann-Pick C1 (NPC1) is a lysosomal membrane protein that exports cholesterol derived from receptor-mediated uptake of LDL, and it also mediates cellular entry of Ebola virus. Cholesterol export is inhibited by nanomolar concentrations of U18666A, a cationic sterol. To identify the target of U18666A, we synthesized U-X, a U18666A derivative with a benzophenone that permits ultraviolet-induced crosslinking. When added to CHO cells, U-X crosslinked to NPC1. Crosslinking was blocked by U18666A derivatives that block cholesterol export, but not derivatives lacking blocking activity. Crosslinking was prevented by point mutation in the sterol-sensing domain (SSD) of NPC1, but not by point mutation in the N-terminal domain (NTD). These data suggest that the SSD contains a U18666A-inhibitable site required for cholesterol export distinct from the cholesterol-binding site in the NTD. Inasmuch as inhibition of Ebola requires 100-fold higher concentrations of U18666A, the high affinity U16888A-binding site is likely not required for virus entry.

Article and author information

Author details

  1. Feiran Lu

    Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Qiren Liang

    Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Lina Abi-Mosleh

    Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Akash Das

    Department of Molecular Genetics, The University of Texas Southwestern Medical Center, Dallas, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Jef K De Brabander

    Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Joseph L Goldstein

    Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, United States
    For correspondence
    joe.goldstein@utsouthwestern.edu
    Competing interests
    The authors declare that no competing interests exist.
  7. Michael S Brown

    Department of Molecular Genetics, The University of Texas Southwestern Medical Center, Dallas, United States
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Peter Tontonoz, Howard Hughes Medical Institute, University of California, Los Angeles, United States

Publication history

  1. Received: October 9, 2015
  2. Accepted: November 8, 2015
  3. Accepted Manuscript published: December 8, 2015 (version 1)
  4. Version of Record published: January 7, 2016 (version 2)

Copyright

© 2015, Lu 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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