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Updated: Jul 11, 2026

Isolation and Functional Analysis of Mitochondria from Cultured Cells and Mouse Tissue
Published on: March 23, 2015
Protein import into mitochondria
1Institute for Physiological Chemistry, Ludwig-Maximilians-University, Butenandtstr. 5, 81377 Munich, Germany.
Abstract:
Mitochondria comprise approx. 1000-3000 different proteins, almost all of which must be imported from the cytosol into the organelle. So far, six complex molecular machines, protein translocases, were identified that mediate this process. The TIM23 complex is a major translocase in the inner mitochondrial membrane. It uses two energy sources, namely membrane potential and ATP, to facilitate preprotein translocation across the inner membrane and insertion into the inner membrane. Recent research has led to the discovery of a number of new constituents of the TIM23 complex and to the unravelling of the mechanisms of preprotein translocation.
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