title: PIM1 encodes a mitochondrial ATP-dependent protease that is required for mitochondrial function in the yeast Saccharomyces cerevisiae.
abstract: The PIM1 nuclear gene in the yeast Saccharomyces cerevisiae encodes a mitochondrial ATP-dependent protease that exhibits over 30% identity with ATP-dependent protease La from Escherichia coli, Lon from Bacillus brevis, and one from Myxococcus xanthus. In addition, Pim1 is 1133 amino acids long and has a putative mitochondrial import signal in the N-terminal region. Enzymatic comparisons of normal PIM1+ and deficient pim1-delta strains revealed that the ATP-dependent protease is located within the mitochondrial matrix. The pim1-delta strains are unable to utilize nonfermentable substrates as the sole carbon source and are unable to maintain functional mitochondrial DNA, indicating that the Pim1 protease is required for mitochondrial function. PIM1 mRNA is constitutively expressed but is increased after thermal stress, suggesting that Pim1 may play a role in the heat shock response.
authors.affiliation: Unité de Biochimie Physiologique, Université Catholique de Louvain, Belgium.
authors.forename: L
authors.initials: L
authors.lastname: Van Dyck
authors.forename: D A
authors.initials: DA
authors.lastname: Pearce
authors.forename: F
authors.initials: F
authors.lastname: Sherman
mesh_terms: D049069:ATP-Dependent Proteases; D000595:Amino Acid Sequence; D001483:Base Sequence; D004271:DNA, Fungal; D004272:DNA, Mitochondrial; D029968:Escherichia coli Proteins; D005800:Genes, Fungal; D006360:Heat-Shock Proteins / Q000235:genetics* / Q000378:metabolism; D006358:Hot Temperature; D008928:Mitochondria / Q000201:enzymology* / Q000502:physiology; D024101:Mitochondrial Proteins; D008969:Molecular Sequence Data; D049070:Protease La; D012441:Saccharomyces cerevisiae / Q000201:enzymology*; D029701:Saccharomyces cerevisiae Proteins; D017386:Sequence Homology, Amino Acid; D012697:Serine Endopeptidases / Q000235:genetics* / Q000378:metabolism; D014158:Transcription, Genetic
chemical_list: D004271:DNA, Fungal; D004272:DNA, Mitochondrial; D029968:Escherichia coli Proteins; D006360:Heat-Shock Proteins; D024101:Mitochondrial Proteins; D029701:Saccharomyces cerevisiae Proteins; D049069:ATP-Dependent Proteases; C085155:PIM1 protein, S cerevisiae; D012697:Serine Endopeptidases; C483567:Lon protein, E coli; D049070:Protease La