1. Structural Biology and Molecular Biophysics

Architecture and dynamics of the autophagic phosphatidylinositol 3-kinase complex

  1. Sulochanadevi Baskaran
  2. Lars-Anders Carlson
  3. Goran Stjepanovic
  4. Lindsey N Young
  5. Do Jin Kim
  6. Patricia Grob
  7. Robin E Stanley
  8. Eva Nogales
  9. James H Hurley  Is a corresponding author
  1. University of California, Berkeley, United States
  2. Howard Hughes Medical Institute, University of California, Berkeley, United States
  3. Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, United States
https://doi.org/10.7554/eLife.05115
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Cite this article
  1. Sulochanadevi Baskaran
  2. Lars-Anders Carlson
  3. Goran Stjepanovic
  4. Lindsey N Young
  5. Do Jin Kim
  6. Patricia Grob
  7. Robin E Stanley
  8. Eva Nogales
  9. James H Hurley
(2014)
Architecture and dynamics of the autophagic phosphatidylinositol 3-kinase complex
eLife 3:e05115.
https://doi.org/10.7554/eLife.05115
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Abstract

The class III phosphatidylinositol 3-kinase complex I (PI3KC3-C1) that functions in early autophagy consists of the lipid kinase VPS34, the scaffolding protein VPS15, the tumor suppressor BECN1, and the autophagy-specific subunit ATG14. The structure of the ATG14-containing PI3KC3-C1 was determined by single-particle EM, revealing a V-shaped architecture. All of the ordered domains of VPS34, VPS15, and BECN1 were mapped by MBP tagging. The dynamics of the complex were defined using hydrogen-deuterium exchange, revealing a novel 20-residue ordered region C-terminal to the VPS34 C2 domain. VPS15 organizes the complex and serves as a bridge between VPS34 and the ATG14:BECN1 subcomplex. Dynamic transitions occur in which the lipid kinase domain is ejected from the complex and VPS15 pivots at the base of the V. The N-terminus of BECN1, the target for signaling inputs, resides near the pivot point. These observations provide a framework for understanding the allosteric regulation of lipid kinase activity.

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Author details

  1. Sulochanadevi Baskaran

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.

  2. Lars-Anders Carlson

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.

  3. Goran Stjepanovic

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.

  4. Lindsey N Young

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.

  5. Do Jin Kim

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.

  6. Patricia Grob

    Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.

  7. Robin E Stanley

    National Institutes of Health, Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.

  8. Eva Nogales

    Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.

  9. James H Hurley

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    For correspondence
    jimhurley@berkeley.edu
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Werner Kühlbrandt, Max Planck Institute of Biophysics, Germany

Version history

  1. Received: October 10, 2014
  2. Accepted: December 8, 2014
  3. Accepted Manuscript published: December 9, 2014 (version 1)
  4. Version of Record published: January 2, 2015 (version 2)

Copyright

This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.

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  1. Sulochanadevi Baskaran
  2. Lars-Anders Carlson
  3. Goran Stjepanovic
  4. Lindsey N Young
  5. Do Jin Kim
  6. Patricia Grob
  7. Robin E Stanley
  8. Eva Nogales
  9. James H Hurley
(2014)
Architecture and dynamics of the autophagic phosphatidylinositol 3-kinase complex
eLife 3:e05115.
https://doi.org/10.7554/eLife.05115

Share this article

https://doi.org/10.7554/eLife.05115

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