Related Experiment Video
Updated: Jul 7, 2026

An Improved Method to Isolate Mitochondrial Contact Sites
Published on: June 16, 2023
Structure, topology and function of the translocase of the outer membrane of mitochondria
Andrew J Perry1, Kieran A Rimmer, Haydyn D T Mertens
1Department of Biochemistry and Molecular Biology, Bio21 Institute of Biotechnology and Molecular Science, University of Melbourne, Parkville, Victoria 3010, Australia.
Abstract:
Proteins destined for the mitochondria required the evolution of specific and efficient molecular machinery for protein import. The subunits of the import translocases of the inner membrane (TIM) appear homologous and conserved amongst species, however the components of the translocase of the outer membrane (TOM) show extensive differences between species. Recently, bioinformatic and structural analysis of Tom20, an important receptor subunit of the TOM complex, suggests that this protein complex arose from different ancestors for plants compared to animals and fungi, but has subsequently converged to provide similar functions and analogous structures. Here we review the current knowledge of the TOM complex, the function and structure of the various subunits that make up this molecular machine.
Related Concept Videos
Translocation of Proteins into the Mitochondria
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...
Protein Transport into the Inner Mitochondrial Membrane
Transport of mitochondrial precursors across the TIM23 channel is driven by...
Mitochondrial Membranes
Mitochondrial Membranes
Mitochondrial Protein Sorting
Most of these mitochondrial proteins are encoded by the nucleus and imported to the mitochondria as unfolded or loosely folded precursors. Mitochondrial precursors...
The Inner Mitochondrial Membrane

