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Assembling the mitochondrial outer membrane

Nature Structural & Molecular Biology volume 11, pages 1044–1048 (2004)Cite this article

Abstract

The general preprotein translocase of the outer mitochondrial membrane (TOM complex) transports virtually all mitochondrial precursor proteins, but cannot assemble outer-membrane precursors into functional complexes. A recently discovered sorting and assembly machinery (SAM complex) is essential for integration and assembly of outer-membrane proteins, revealing unexpected connections to mitochondrial evolution and morphology.

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Figure 1: Protein import pathways into mitochondria.
Figure 2: The protein import and sorting machineries of the mitochondrial outer membrane.
Figure 3: Conservation of β-barrel insertion into the outer membranes of mitochondria and Gram-negative bacteria.

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Acknowledgements

We are grateful to G. Schatz, F. Paltauf, S.D. Kohlwein, J. Soll, R.E. Jensen, K.Mihara, I. Gentle and M.T. Ryan for discussion and support in clarifying the nomenclature of the SAM subunits according to the rules of the Saccharomyces genome database (SGD). Work of the authors' laboratories was supported by the Deutsche Forschungsgemeinschaft, Sonderforschungsbereich 388, Gottfried Wilhelm Leibniz Programme, Max Planck Research Award, Alexander von Humboldt Foundation, Bundesministerium für Bildung und Forschung, the Fonds der Chemischen Industrie and the Australian Research Council.

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  1. Institut für Biochemie und Molekularbiologie, Universität Freiburg, Hermann-Herder-Str. 7, Freiburg, D-79104, Germany

    Nikolaus Pfanner, Nils Wiedemann & Chris Meisinger

  2. Russell Grimwade School of Biochemistry and Molecular Biology, University of Melbourne, Melbourne, 3010, Australia

    Trevor Lithgow

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Correspondence to Nikolaus Pfanner or Chris Meisinger.

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Pfanner, N., Wiedemann, N., Meisinger, C. et al. Assembling the mitochondrial outer membrane. Nat Struct Mol Biol 11, 1044–1048 (2004). https://doi.org/10.1038/nsmb852

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