Tim29 is a novel subunit of the human TIM22 translocase and is involved in complex assembly and stability

  1. Yilin Kang
  2. Michael James Baker
  3. Michael Liem
  4. Jade Louber
  5. Matthew McKenzie
  6. Ishara Atukorala
  7. Ching-Seng Ang
  8. Shivakumar Keerthikumar
  9. Suresh Mathivanan
  10. Diana Stojanovski  Is a corresponding author
  1. The University of Melbourne, Australia
  2. La Trobe University, Australia
  3. Hudson Institute of Medical Research, Australia

Abstract

The TIM22 complex mediates the import of hydrophobic carrier proteins into the mitochondrial inner membrane. While the TIM22 machinery has been well characterised in yeast, the human complex remains poorly characterised. Here, we identify Tim29 (C19orf52) as a novel, metazoan-specific subunit of the human TIM22 complex. The protein is integrated into the mitochondrial inner membrane with it's C-terminus exposed to the intermembrane space. Tim29 is required for the stability of the TIM22 complex and functions in the assembly of the hTim22. Furthermore, Tim29 contacts the Translocase of the Outer Mitochondrial Membrane, TOM complex, enabling a mechanism for transport of hydrophobic carrier substrates across the aqueous intermembrane space. Identification of Tim29 highlights the significance of analysing mitochondrial import systems across phylogenetic boundaries, which can reveal novel components and mechanisms in higher organisms.

Article and author information

Author details

  1. Yilin Kang

    Department of Biochemistry and Molecular Biology, The University of Melbourne, Melbourne, Australia
    Competing interests
    The authors declare that no competing interests exist.
  2. Michael James Baker

    Department of Biochemistry and Molecular Biology, The University of Melbourne, Melbourne, Australia
    Competing interests
    The authors declare that no competing interests exist.
  3. Michael Liem

    Department of Biochemistry and Genetics, La Trobe University, Melbourne, Australia
    Competing interests
    The authors declare that no competing interests exist.
  4. Jade Louber

    Department of Biochemistry and Molecular Biology, The University of Melbourne, Melbourne, Australia
    Competing interests
    The authors declare that no competing interests exist.
  5. Matthew McKenzie

    Centre for Genetic Diseases, Hudson Institute of Medical Research, Melbourne, Australia
    Competing interests
    The authors declare that no competing interests exist.
  6. Ishara Atukorala

    Department of Biochemistry and Genetics, La Trobe University, Melbourne, Australia
    Competing interests
    The authors declare that no competing interests exist.
  7. Ching-Seng Ang

    The Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, Australia
    Competing interests
    The authors declare that no competing interests exist.
  8. Shivakumar Keerthikumar

    Department of Biochemistry and Genetics, La Trobe University, Melbourne, Australia
    Competing interests
    The authors declare that no competing interests exist.
  9. Suresh Mathivanan

    Department of Biochemistry and Genetics, La Trobe University, Melbourne, Australia
    Competing interests
    The authors declare that no competing interests exist.
  10. Diana Stojanovski

    Department of Biochemistry and Molecular Biology, The University of Melbourne, Melbourne, Australia
    For correspondence
    d.stojanovski@unimelb.edu.au
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0199-3222

Funding

The authors declare that there was no funding for this work

Reviewing Editor

  1. Nikolaus Pfanner, University of Freiburg, Germany

Version history

  1. Received: May 4, 2016
  2. Accepted: August 14, 2016
  3. Accepted Manuscript published: August 24, 2016 (version 1)
  4. Version of Record published: September 8, 2016 (version 2)
  5. Version of Record updated: December 1, 2016 (version 3)

Copyright

© 2016, Kang 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. Yilin Kang
  2. Michael James Baker
  3. Michael Liem
  4. Jade Louber
  5. Matthew McKenzie
  6. Ishara Atukorala
  7. Ching-Seng Ang
  8. Shivakumar Keerthikumar
  9. Suresh Mathivanan
  10. Diana Stojanovski
(2016)
Tim29 is a novel subunit of the human TIM22 translocase and is involved in complex assembly and stability
eLife 5:e17463.
https://doi.org/10.7554/eLife.17463

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