The Mitochondrial ClpB Homolog Hsp78 Cooperates with Matrix Hsp70 in Maintenance of Mitochondrial Function
| Autor: | Birgit Schönfisch, Wolfgang Voos, M Moczko, Nikolaus Pfanner, Joachim Rassow |
|---|---|
| Rok vydání: | 1995 |
| Předmět: |
Mitochondrial DNA
Saccharomyces cerevisiae Proteins Mutant Saccharomyces cerevisiae Mitochondrion Biology Membrane Potentials Fungal Proteins Structural Biology Heat shock protein Point Mutation HSP70 Heat-Shock Proteins Molecular Biology Heat-Shock Proteins HSPA9 Sequence Homology Amino Acid Escherichia coli Proteins Cell Membrane Endopeptidase Clp Mitochondrial carrier Extracellular Matrix Mitochondria Biochemistry DNAJA3 ATP–ADP translocase Cell Division Gene Deletion |
| Zdroj: | Journal of Molecular Biology. 254:538-543 |
| ISSN: | 0022-2836 |
| DOI: | 10.1006/jmbi.1995.0636 |
| Popis: | The mitochondrial heat shock protein Hsp78 is a member of the Hsp104/Clp family with unknown function.Saccharomyces cerevisiaedeletion mutants ofHSP78show wild-type like growth. We report that deletion of theHSP78gene in yeast strains with point mutations in theSSC1gene (encoding matrix Hsp70) led to loss of mitochondrial DNA, indicating that at least one of the heat shock proteins Hsp78 and mt-Hsp70 is needed to maintain a rho+state of the mitochondrial genome. Mitochondria isolated from these double mutants had a strongly reduced membrane potential, explaining defects in the rate of preprotein import. The lack of Hsp78 led to aggregation of the mutant mt-Hsp70s while other matrix chaperones stayed soluble. We conclude that Hsp78 is required to keep mutant forms of mt-Hsp70 soluble and suggest a cooperation of Hsp78 and mt-Hsp70 in maintenance of essential mitochondrial functions. |
| Databáze: | OpenAIRE |
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