Untersuchungen zur Proteintranslokation über die innere Mitochondrienmembran - Regulation der Aktivität des Proteinimportmotors

• Applicant: Dr. Dirk Schiller
• Subject Area: Biochemistry
• Term: from 2004 to 2006
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5446404

Mitochondria are essential for the energy metabolism of the eukaryotic cell. Although they contain their own genetic apparatus, the vast majority of mitochondrial enzymes are synthesized as precursors in the cytosol and must pass through the presequence translocase of the inner membrane. Translocation of preproteins is accomplished by a regulated and concerted action of the components of the import motor, namely Tim44, Pam18, Pam16, Mge1 and mtHsp70. The peripheral membrane protein Tim44 tethers the mitochondrial chaperone mtHsp70 (Ssc1 in yeast) to the exit of the import channel where it binds to the incoming polypeptide chain. Translocation is achieved by cycles of consecutive binding of mtHsp70 to Tim44 and to the peptide substrate. Despite the central role of the Tim44:mtHsp70 interaction in protein import little is known about the molecular mechanism of that regulatory protein protein interaction. To elucidate how Tim44 is involved in protein translocation, genetic, biochemical, biophysical and structural analyses of Tim44 will be carried out to understand the mechanism and the regulation of the Tim44:mtHsp70 interaction in protein import into the mitochondrial matix.

• DFG Programme: Research Fellowships
• International Connection: USA
• Cooperation Partner: Professorin Dr. Elizabeth A. Craig