Open AccessRequirement of a Membrane Potential for the Posttranslational Transfer of Proteins into Mitochondsria
Author(s) -
SCHLEYER Manfred,
SCHMIDT Bernd,
NEUPERT Walter
Publication year - 1982
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1982.tb06657.x
Subject(s) - mitochondrion , neurospora , atp synthase , microbiology and biotechnology , atp–adp translocase , chemiosmosis , membrane potential , biochemistry , atpase , membrane , intracellular , mitochondrial carrier , membrane protein , translocase of the inner membrane , inner mitochondrial membrane , protein subunit , biology , inner membrane , mitochondrial membrane transport protein , bacterial outer membrane , enzyme , neurospora crassa , escherichia coli , mutant , gene
Posttranslational transfer of most precursor proteins into mitochondria is dependent on energization of the mitochondria. Experiments were carried out to determine whether the membrane potential or the intramitochondrial ATP is the immediate energy source. Transfer in vitro of precursors to the ADP/ATP carrier and to ATPase subunit 9 into isolated Neurospora mitochondria was investigated. Under conditions where the level of intramitochondrial ATP was high and the membrane potential was dissipated, import and processing of these precursor proteins did not take place. On the other hand, precursors were taken up and processed when the intramitochondrial ATP level was low, but the membrane potential was not dissipated. We conclude that a membrane potential is involved in the import of those mitochondrial precursor proteins which require energy for intracellular translocation