SGD gene description for HSP78 (yeast)
The ClpB homolog Hsp78 is required for the efficient degradation of proteins in the mitochondrial matrix.
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hsp78 mitochondria are defective in Pim1-mediated degradation of imported reporter proteins, independently of substrate aggregation.
"We conclude that Hsp78 is a genuine component of the mitochondrial proteolysis system required for the efficient degradation of substrate proteins in the matrix."
Severe ethanol stress induces the preferential synthesis of mitochondrial disaggregase Hsp78 and formation of DUMPs in Saccharomyces cerevisiae.
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Hsp78 is preferentially synthesized under severe ethanol stress, and hsp78 cells accumulate mitochondrial protein aggregates and respiration-deficient mutants.
"Aggregation of mitochondrial proteins and formation of DUMPs were accelerated in hsp78∆ cells compared with those in wild-type cells."
Yeast Hsp78 plays an essential role in adapting to severe ethanol stress via mild ethanol stress pretreatment in mitochondrial protein quality control.
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Mild ethanol pretreatment reduces mitochondrial aggregates under later severe ethanol stress in wild type but not hsp78 cells.
"Pretreatment with 6 % (v/v) ethanol significantly mitigated the formation of DUMPs and Aco1 aggregates under subsequent 10 % ethanol stress in wild-type cells but not in hsp78∆ and mdj1∆ cells."
Gene Ontology annotation through association of InterPro records with GO terms
Annotation inferences using phylogenetic trees
Gene Ontology annotation based on UniProtKB/Swiss-Prot Subcellular Location vocabulary mapping, accompanied by conservative changes to GO terms applied by UniProt
Electronic Gene Ontology annotations created by ARBA machine learning models
Combined Automated Annotation using Multiple IEA Methods
Importance of two ATP-binding sites for oligomerization, ATPase activity and chaperone function of mitochondrial Hsp78 protein.
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Purified Hsp78 forms an ATP-dependent homohexamer, has ATPase activity, and cooperates with the mitochondrial Hsp70 system to reactivate substrate proteins.
"Studies on the chaperone activity of Hsp78 show that its cooperation with the mitochondrial Hsp70 system, consisting of Ssc1p, Mdj1p and Mge1p, is needed for the efficient reactivation of substrate proteins."
Proteome survey reveals modularity of the yeast cell machinery.
The disaggregation activity of the mitochondrial ClpB homolog Hsp78 maintains Hsp70 function during heat stress.
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Hsp78 has ATP-dependent mitochondrial disaggregation activity and resolubilizes heat-induced protein aggregates in intact mitochondria.
"By establishing an aggregation/disaggregation assay in intact mitochondria we demonstrated that Hsp78 is indispensable for the resolubilization of protein aggregates generated by heat stress under in vivo conditions."
Toward the complete yeast mitochondrial proteome: multidimensional separation techniques for mitochondrial proteomics.
CDK-dependent Hsp70 Phosphorylation controls G1 cyclin abundance and cell-cycle progression.
Quantitative variations of the mitochondrial proteome and phosphoproteome during fermentative and respiratory growth in Saccharomyces cerevisiae.
Hsp78, a Clp homologue within mitochondria, can substitute for chaperone functions of mt-hsp70.
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Hsp78 binds newly imported mitochondrial polypeptides and prevents misfolded matrix proteins from aggregating when mitochondrial Hsp70 is impaired.
"hsp78 suppresses the defect in mitochondrial protein import under permissive conditions in vitro and interacts directly with newly imported polypeptide chains."
HSP78 encodes a yeast mitochondrial heat shock protein in the Clp family of ATP-dependent proteases.
The molecular chaperone Hsp78 confers compartment-specific thermotolerance to mitochondria.
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Hsp78 protects mitochondrial respiration and genome integrity during severe temperature stress.
"Hsp78 is crucial for maintenance of respiratory competence and for mitochondrial genome integrity under severe temperature stress (mitochondrial thermotolerance)."