Mitochondrial Machineries for Protein Import and Assembly

Nils Wiedemann; Nikolaus Pfanner

doi:10.1146/annurev-biochem-060815-014352

Mitochondrial Machineries for Protein Import and Assembly

Annu Rev Biochem. 2017 Jun 20:86:685-714. doi: 10.1146/annurev-biochem-060815-014352. Epub 2017 Mar 15.

Authors

Nils Wiedemann¹, Nikolaus Pfanner¹

Affiliation

¹ Institute of Biochemistry and Molecular Biology, ZBMZ, Faculty of Medicine, and BIOSS Centre for Biological Signaling Studies, University of Freiburg, 79104 Freiburg, Germany; email: nils.wiedemann@biochemie.uni-freiburg.de , nikolaus.pfanner@biochemie.uni-freiburg.de.

PMID: 28301740
DOI: 10.1146/annurev-biochem-060815-014352

Abstract

Mitochondria are essential organelles with numerous functions in cellular metabolism and homeostasis. Most of the >1,000 different mitochondrial proteins are synthesized as precursors in the cytosol and are imported into mitochondria by five transport pathways. The protein import machineries of the mitochondrial membranes and aqueous compartments reveal a remarkable variability of mechanisms for protein recognition, translocation, and sorting. The protein translocases do not operate as separate entities but are connected to each other and to machineries with functions in energetics, membrane organization, and quality control. Here, we discuss the versatility and dynamic organization of the mitochondrial protein import machineries. Elucidating the molecular mechanisms of mitochondrial protein translocation is crucial for understanding the integration of protein translocases into a large network that controls organelle biogenesis, function, and dynamics.

Keywords: inner membrane; mitochondrial architecture; outer membrane; preprotein; protein sorting; translocase.

Publication types

Review

MeSH terms

Carrier Proteins / chemistry
Carrier Proteins / genetics
Carrier Proteins / metabolism*
Eukaryotic Cells / metabolism
Eukaryotic Cells / ultrastructure
Gene Expression
Humans
Isoenzymes / chemistry
Isoenzymes / genetics
Isoenzymes / metabolism
Mitochondria / metabolism*
Mitochondria / ultrastructure
Mitochondrial Membrane Transport Proteins / chemistry
Mitochondrial Membrane Transport Proteins / genetics
Mitochondrial Membrane Transport Proteins / metabolism*
Mitochondrial Membranes / metabolism*
Mitochondrial Membranes / ultrastructure
Mitochondrial Precursor Protein Import Complex Proteins
Mitochondrial Proteins / chemistry
Mitochondrial Proteins / genetics
Mitochondrial Proteins / metabolism*
Organelle Biogenesis
Protein Conformation, alpha-Helical
Protein Conformation, beta-Strand
Protein Precursors / chemistry
Protein Precursors / genetics
Protein Precursors / metabolism*
Protein Transport

Substances

Carrier Proteins
Isoenzymes
Mitochondrial Membrane Transport Proteins
Mitochondrial Precursor Protein Import Complex Proteins
Mitochondrial Proteins
Protein Precursors
TIMM23 protein, human