Most mitochondrial proteins are encoded by nuclear genes and then synthesized as
precursors on cytosolic ribosomes after which they must be imported into the organelle. The
mitochondrial membranes contain specific machineries (translocases) for recognition,
translocation, and membrane insertion of precursor proteins. In recent years, important
progress has been made in characterizing the molecular mechanisms and cooperation of
the mitochondrial preprotein translocases. Here, we will summarize the principles of …