Yge1p, a eukaryotic Grp-E homolog, is localized in the mitochondrial matrix and interacts with mitochondrial Hsp70.
Yeast Yge1p, the gene product of YGE1, is a eukaryotic GrpE homolog found recently (Ikeda et al., 1994). We have revealed here that Yge1p is a soluble protein in the mitochondrial matrix. Depletion of Yge1p in yeast cells resulted in accumulation of the precursor of F1-ATPase beta subunit in vivo, suggesting that Yge1p is involved in protein import into mitochondria. Overexpression of Yge1p in the temperature-sensitive mutant strains of mitochondrial hsp70, Ssc1p, caused hypersensitivity to temperature for cell growth, suggesting a genetic interaction between the YGE1 and SSC1 genes. A physical interaction between Yge1p and Ssc1p was directly demonstrated by co-immunoprecipitation of Ssc1p by the anti-Yge1p antibodies. We propose that Yge1p functions in cooperation with Ssc1p in a similar manner as bacterial GrpE with DnaK.
Nakai
M
M
Department of Chemistry, Faculty of Science, Nagoya University, Japan.
Kato
Y
Y
Ikeda
E
E
Toh-e
A
A
Endo
T
T
D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D005656:Fungal Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D005800:Genes, Fungal; D006360:Heat-Shock Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D026901:Membrane Transport Proteins; D008928:Mitochondria / Q000378:metabolism*; D033681:Mitochondrial Membrane Transport Proteins; D018832:Molecular Chaperones; D016296:Mutagenesis; D011485:Protein Binding; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins; D013367:Submitochondrial Particles / Q000378:metabolism; D013696:Temperature
D001426:Bacterial Proteins; D005656:Fungal Proteins; C068113:GrpE protein, Bacteria; D006360:Heat-Shock Proteins; C086039:MGE1 protein, S cerevisiae; D026901:Membrane Transport Proteins; D033681:Mitochondrial Membrane Transport Proteins; D018832:Molecular Chaperones; D029701:Saccharomyces cerevisiae Proteins