title: A human mitochondrial ATP-dependent protease that is highly homologous to bacterial Lon protease.
abstract: We have cloned a human ATP-dependent protease that is highly homologous to members of the bacterial Lon protease family. The cloned gene encodes a protein of 963 amino acids with a calculated molecular mass of 106 kDa, slightly higher than that observed by Western blotting the protein from human tissues and cell lines (100 kDa). A single species of mRNA was found for this Lon protease in all human tissues examined. The protease is encoded in the nucleus, and the amino-terminal portion of the protein sequence contains a potential mitochondrial targeting presequence. Immunofluorescence microscopy suggested a predominantly mitochondrial localization for the Lon protease in cultured human cells. A truncated LON gene, in which translation was initiated at Met118 of the coding sequence, was expressed in Escherichia coli and produced a protease that degraded alpha-casein in vitro in an ATP-dependent manner and had other properties similar to E. coli Lon protease.
authors.affiliation: Laboratory of Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892.
authors.forename: N
authors.initials: N
authors.lastname: Wang
authors.forename: S
authors.initials: S
authors.lastname: Gottesman
authors.forename: M C
authors.initials: MC
authors.lastname: Willingham
authors.forename: M M
authors.initials: MM
authors.lastname: Gottesman
authors.forename: M R
authors.initials: MR
authors.lastname: Maurizi
mesh_terms: D049069:ATP-Dependent Proteases; D000595:Amino Acid Sequence; D001483:Base Sequence; D015153:Blotting, Western; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D029968:Escherichia coli Proteins; D005796:Genes; D006360:Heat-Shock Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D006801:Humans; D008928:Mitochondria / Q000201:enzymology*; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D049070:Protease La; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D012697:Serine Endopeptidases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D013329:Structure-Activity Relationship; D014018:Tissue Distribution
chemical_list: D018076:DNA, Complementary; D029968:Escherichia coli Proteins; D006360:Heat-Shock Proteins; D049069:ATP-Dependent Proteases; D012697:Serine Endopeptidases; C483567:Lon protein, E coli; D049070:Protease La