Assembly of the three small Tim proteins precedes docking to the mitochondrial carrier translocase
Autor: | Nils Wiedemann, Natalia Gebert, Peter Rehling, Karina Wagner, Carla M. Koehler, Bernard Guiard, Nikolaus Pfanner, Agnieszka Chacinska |
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Jazyk: | angličtina |
Rok vydání: | 2008 |
Předmět: |
Saccharomyces cerevisiae Proteins
Mitochondrial intermembrane space Translocase of the outer membrane Scientific Report TIM/TOM complex Saccharomyces cerevisiae Biochemistry Mitochondrial Membrane Transport Proteins Mitochondrial Proteins 03 medical and health sciences Mitochondrial Precursor Protein Import Complex Proteins Genetics Translocase Protein Precursors Molecular Biology 030304 developmental biology 0303 health sciences biology 030302 biochemistry & molecular biology Membrane Proteins Membrane Transport Proteins Mitochondrial carrier Cell biology Protein Subunits Multiprotein Complexes Translocase of the inner membrane biology.protein ATP–ADP translocase Intermembrane space Mitochondrial ADP ATP Translocases |
Popis: | The mitochondrial intermembrane space contains a family of small Tim proteins that function as essential chaperones for protein import. The soluble Tim9–Tim10 complex transfers hydrophobic precursor proteins through the aqueous intermembrane space to the carrier translocase of the inner membrane (TIM22 complex). Tim12, a peripheral membrane subunit of the TIM22 complex, is thought to recruit a portion of Tim9–Tim10 to the inner membrane. It is not known, however, how Tim12 is assembled. We have identified a new intermediate in the biogenesis pathway of Tim12. A soluble form of Tim12 first assembles with Tim9 and Tim10 to form a Tim12-core complex. Tim12-core then docks onto the membrane-integrated subunits of the TIM22 complex to form the holo-translocase. Thus, the function of Tim12 in linking soluble and membrane-integrated subunits of the import machinery involves a sequential assembly mechanism of the translocase through a soluble intermediate complex of the three essential small Tim proteins. |
Databáze: | OpenAIRE |
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