title: 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 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.
authors.affiliation: Department of Biochemistry and Molecular Biology, The University of Melbourne, Melbourne, Australia.|The Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, Australia.
authors.forename: Yilin
authors.initials: Y
authors.lastname: Kang
authors.affiliation: Department of Biochemistry and Molecular Biology, The University of Melbourne, Melbourne, Australia.|The Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, Australia.
authors.forename: Michael James
authors.initials: MJ
authors.lastname: Baker
authors.affiliation: Department of Biochemistry and Genetics, La Trobe University, Melbourne, Australia.|La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Australia.
authors.forename: Michael
authors.initials: M
authors.lastname: Liem
authors.affiliation: Department of Biochemistry and Molecular Biology, The University of Melbourne, Melbourne, Australia.|The Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, Australia.
authors.forename: Jade
authors.initials: J
authors.lastname: Louber
authors.affiliation: Centre for Genetic Diseases, Hudson Institute of Medical Research, Melbourne, Australia.
authors.forename: Matthew
authors.initials: M
authors.lastname: McKenzie
authors.affiliation: Department of Biochemistry and Genetics, La Trobe University, Melbourne, Australia.|La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Australia.
authors.forename: Ishara
authors.initials: I
authors.lastname: Atukorala
authors.affiliation: The Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, Australia.
authors.forename: Ching-Seng
authors.initials: CS
authors.lastname: Ang
authors.affiliation: Department of Biochemistry and Genetics, La Trobe University, Melbourne, Australia.|La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Australia.
authors.forename: Shivakumar
authors.initials: S
authors.lastname: Keerthikumar
authors.affiliation: Department of Biochemistry and Genetics, La Trobe University, Melbourne, Australia.|La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Australia.
authors.forename: Suresh
authors.initials: S
authors.lastname: Mathivanan
authors.affiliation: Department of Biochemistry and Molecular Biology, The University of Melbourne, Melbourne, Australia.|The Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, Australia.
authors.forename: Diana
authors.identifier: 0000-0002-0199-3222
authors.initials: D
authors.lastname: Stojanovski
mesh_terms: D002460:Cell Line; D006801:Humans; D033681:Mitochondrial Membrane Transport Proteins / Q000032:analysis*; D051336:Mitochondrial Membranes / Q000201:enzymology*; D000090622:Mitochondrial Precursor Protein Import Complex Proteins; D055503:Protein Multimerization; D021122:Protein Subunits / Q000032:analysis*
chemical_list: D033681:Mitochondrial Membrane Transport Proteins; D000090622:Mitochondrial Precursor Protein Import Complex Proteins; D021122:Protein Subunits; C000618451:TIMM29 protein, human
keywords: TIM22; biochemistry; cell biology; human; mitochondria; protein trafficking