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Mechanisms of mitochondrial protein import

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Summary

Import of nuclear encoded precursor proteins into and across the mitochondrial inner membrane is mediated by two distinct translocases, the TIM23 complex and the TIM22 complex, which both cooperate with the general preprotein translocase of the outer membrane, TOM complex. The TIM23 complex mediates import of preproteins with a positively charged matrix-targeting signal, while the TIM22 complex mediates the import of a class of integral inner-membrane proteins which do not carry a matrixtargeting signal. The focus of this review is on the structural organization and function of components that act along these import pathways and their conservation between species.

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Authors and Affiliations

  1. Institute of Clinical Chemistry, Molecular Diagnostics, and Mitochondrial Genetics and Diabetes Research Group, Academic Hospital Munich-Schwabing, Koelnerplatz 1, D-80804, Munich, Federal Republic of Germany

    Mathias F. Bauer

  2. Institute of Physiological Chemistry, Adolf-Butenandt Institute, Ludwig-Maximilians-University Munich, Munich

    Stefan Paschen, Walter Neupert & Michael Brunner

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  1. Mathias F. Bauer
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  2. Stefan Paschen
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  3. Walter Neupert
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  4. Michael Brunner
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Bauer, M.F., Paschen, S., Neupert, W. et al. Mechanisms of mitochondrial protein import. Protoplasma 213, 1–10 (2000). https://doi.org/10.1007/BF01280499

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