A role of OCRL in clathrin-coated pit dynamics and uncoating revealed by studies of Lowe syndrome cells

  1. Ramiro Nández
  2. Daniel M Balkin
  3. Mirko Messa
  4. Liang Liang
  5. Summer Paradise
  6. Heather Czapla
  7. Marco Y Hein
  8. James S Duncan
  9. Matthias Mann
  10. Pietro De Camilli  Is a corresponding author
  1. Yale University School of Medicine, United States
  2. Max Planck Institute of Biochemistry, Germany

Abstract

Mutations in the inositol 5-phosphatase OCRL cause Lowe syndrome and Dent's disease. Although OCRL, a direct clathrin interactor, is recruited to late-stage clathrin-coated pits, clinical manifestations have been primarily attributed to intracellular sorting defects. Here we show that OCRL loss in Lowe syndrome patient fibroblasts impacts clathrin-mediated endocytosis and results in an endocytic defect. These cells exhibit an accumulation of clathrin-coated vesicles and an increase in U-shaped clathrin-coated pits, which may result from sequestration of coat components on uncoated vesicles. Endocytic vesicles that fail to lose their coat nucleate the majority of the numerous actin comets present in patient cells. SNX9, an adaptor that couples late-stage endocytic coated pits to actin polymerization and which we found to bind OCRL directly, remains associated with such vesicles. These results indicate that OCRL acts as an uncoating factor and that defects in clathrin-mediated endocytosis likely contribute to pathology in patients with OCRL mutations.

Article and author information

Author details

  1. Ramiro Nández

    Yale University School of Medicine, New Haven, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Daniel M Balkin

    Yale University School of Medicine, New Haven, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Mirko Messa

    Yale University School of Medicine, New Haven, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Liang Liang

    Yale University School of Medicine, New Haven, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Summer Paradise

    Yale University School of Medicine, New Haven, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Heather Czapla

    Yale University School of Medicine, New Haven, United States
    Competing interests
    The authors declare that no competing interests exist.
  7. Marco Y Hein

    Max Planck Institute of Biochemistry, Martinsried, Germany
    Competing interests
    The authors declare that no competing interests exist.
  8. James S Duncan

    Yale University School of Medicine, New Haven, United States
    Competing interests
    The authors declare that no competing interests exist.
  9. Matthias Mann

    Max Planck Institute of Biochemistry, Munich, Germany
    Competing interests
    The authors declare that no competing interests exist.
  10. Pietro De Camilli

    Yale University School of Medicine, New Haven, United States
    For correspondence
    pietro.decamilli@yale.edu
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Suzanne R Pfeffer, Stanford University, United States

Publication history

  1. Received: April 1, 2014
  2. Accepted: August 7, 2014
  3. Accepted Manuscript published: August 8, 2014 (version 1)
  4. Version of Record published: September 18, 2014 (version 2)

Copyright

© 2014, Nández 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. Ramiro Nández
  2. Daniel M Balkin
  3. Mirko Messa
  4. Liang Liang
  5. Summer Paradise
  6. Heather Czapla
  7. Marco Y Hein
  8. James S Duncan
  9. Matthias Mann
  10. Pietro De Camilli
(2014)
A role of OCRL in clathrin-coated pit dynamics and uncoating revealed by studies of Lowe syndrome cells
eLife 3:e02975.
https://doi.org/10.7554/eLife.02975

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