Title: Hsp78, a Clp homologue within mitochondria, can substitute for chaperone functions of mt-hsp70.
Abstract: Research Article17 July 1995free access Hsp78, a Clp homologue within mitochondria, can substitute for chaperone functions of mt-hsp70. M. Schmitt M. Schmitt Institut für Physiologische Chemie der Universität München, Germany. Search for more papers by this author W. Neupert W. Neupert Institut für Physiologische Chemie der Universität München, Germany. Search for more papers by this author T. Langer T. Langer Institut für Physiologische Chemie der Universität München, Germany. Search for more papers by this author M. Schmitt M. Schmitt Institut für Physiologische Chemie der Universität München, Germany. Search for more papers by this author W. Neupert W. Neupert Institut für Physiologische Chemie der Universität München, Germany. Search for more papers by this author T. Langer T. Langer Institut für Physiologische Chemie der Universität München, Germany. Search for more papers by this author Author Information M. Schmitt1, W. Neupert1 and T. Langer1 1Institut für Physiologische Chemie der Universität München, Germany. The EMBO Journal (1995)14:3434-3444https://doi.org/10.1002/j.1460-2075.1995.tb07349.x PDFDownload PDF of article text and main figures. ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinked InMendeleyWechatReddit Figures & Info Hsp78 is a Clp homologue within mitochondria of Saccharomyces cerevisiae. Deletion of HSP78 does not cause any detectable changes in wild type cells, but results in a petite phenotype in the ssc1-3 mutant strain carrying a temperature-sensitive allele of mt-hsp70. When overexpressed in the ssc1-3 mutant strain, hsp78 suppresses the defect in mitochondrial protein import under permissive conditions in vitro and interacts directly with newly imported polypeptide chains. As a molecular chaperone, hsp78 prevents the aggregation of misfolded proteins in the matrix of mitochondria under conditions of impaired mt-hsp70 function. However, unlike misfolded proteins associated with mt-hsp70, hsp78-bound polypeptides are not efficiently degraded by the ATP-dependent PIM1 protease. Thus, hsp78 can partially substitute for mt-hsp70 functions in the assembly of mitochondria and may be part of a salvage pathway if mt-hsp70 is limiting. Previous ArticleNext Article Volume 14Issue 141 July 1995In this issue RelatedDetailsLoading ...