Tim29 is a novel subunit of the human TIM22 translocase and is involved in complex assembly and stability
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.
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The authors declare that there was no funding for this work
Reviewing Editor
- Nikolaus Pfanner, University of Freiburg, Germany
Version history
- Received: May 4, 2016
- Accepted: August 14, 2016
- Accepted Manuscript published: August 24, 2016 (version 1)
- Version of Record published: September 8, 2016 (version 2)
- 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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