Journal article

Assembly of the Mitochondrial Protein Import Channel Role of Tom5 in Two-Stage Interaction of Tom40 with the SAM Complex

Thomas Becker, Bernard Guiard, Nicolas Thornton, Nicole Zufall, David A Stroud, Nils Wiedemann, Nikolaus Pfanner

MOLECULAR BIOLOGY OF THE CELL | AMER SOC CELL BIOLOGY | Published : 2010

Abstract

The preprotein translocase of the outer mitochondrial membrane (TOM) consists of a central β-barrel channel, Tom40, and six proteins with α-helical transmembrane segments. The precursor of Tom40 is imported from the cytosol by a pre-existing TOM complex and inserted into the outer membrane by the sorting and assembly machinery (SAM). Tom40 then assembles with α-helical Tom proteins to the mature TOM complex. The outer membrane protein Mim1 promotes membrane insertion of several α-helical Tom proteins but also affects the biogenesis of Tom40 by an unknown mechanism. We have identified a novel intermediate in the assembly pathway of Tom40, revealing a two-stage interaction of the precursor wit..

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University of Melbourne Researchers

Grants

Awarded by Trinationales Graduiertenkolleg


Awarded by Excellence Initiative of the German Federal & State Governments



Funding Acknowledgements

We thank Dr. Natalia Gebert for discussion. This work was supported by the Baden-Wurttemberg Stiftung, Deutsche Forschungsgemeinschaft, Sonderforschungsbereich 746, Trinationales Graduiertenkolleg GRK 1478, Excellence Initiative of the German Federal & State Governments (EXC 294 BIOSS; GSC-4 Spemann Graduate School), Bundesministerium fur Bildung und Forschung, Landesforschungspreis Baden-Wurttemberg, Gottfried Wilhelm Leibniz Program, and the Fonds der Chemischen Industrie.