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Updated: May 17, 2026

Analyzing Supercomplexes of the Mitochondrial Electron Transport Chain with Native Electrophoresis, In-gel Assays, and Electroelution
Published on: June 1, 2017
A molecular link between mitochondrial preprotein transporters and respiratory chain complexes
Monika W Murcha1, Yan Wang, James Whelan
1ARC Centre of Excellence in Plant Energy Biology, University of Western Australia, Crawley, WA, Australia. monika.murcha@uwa.edu.au
Abstract:
The TIM17:23 complex on the mitochondrial inner membrane is responsible for import of the majority of mitochondrial proteins in plants. In Arabidopsis, Tim17 and Tim23 belong to a large gene family consisting of 16 members termed the Preprotein and Amino acid transporters (PRAT). Recently, two members of this protein family, Tim23-2 and the Complex I subunit B14.7, have been shown to assemble into both Complex I of the respiratory chain and the TIM17:23 complex (Wang et al., 2012), adding to other examples of links between respiratory and protein import complexes. These associations provide a mechanism to coordinate mitochondrial activity and biogenesis.
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