title: The ATP-dependent Lon protease of Mus musculus is a DNA-binding protein that is functionally conserved between yeast and mammals.
abstract: The ATP-dependent Lon protease is a multi-functional enzyme that is conserved from archae to mammalian mitochondria, which not only degrades protein substrates but also binds DNA. As a starting point toward understanding Lon function in development, the mouse Lon cDNA was cloned and the encoded protein was characterized in cultured mammalian cells, in yeast and in vitro. Mouse Lon shows 87, 40 and 33% amino acid similarity with the human, yeast and bacterial homologs, respectively. Expression of a single mouse Lon transcript is detected in liver>heart>kidney>testis and is present during early embryonic development. Endogenous as well as transiently overexpressed mouse Lon co-localize with mitochondrial markers and have half-lives greater than 24 h as determined by pulse-chase studies. Enzymatically active mouse Lon that hydrolyses ATP and degrades protein and peptide substrates in an ATP-dependent manner also specifically binds to single-stranded but not to double-stranded DNA oligonucleotides. We propose that binding to TG-rich DNA sequences has been conserved between the mouse and human proteins. In addition, the evolutionary conservation of mitochondrial Lon function is demonstrated by the ability of mouse Lon to substitute for the yeast protein in vivo.
authors.affiliation: Department of Biochemistry and Molecular Biology, New Jersey Medical School, University of Medicine and Dentistry of New Jersey, Newark, NJ 07103, USA.
authors.forename: Bin
authors.initials: B
authors.lastname: Lu
authors.forename: Tong
authors.initials: T
authors.lastname: Liu
authors.forename: Juan A
authors.initials: JA
authors.lastname: Crosby
authors.forename: Jennifer
authors.initials: J
authors.lastname: Thomas-Wohlever
authors.forename: Irene
authors.initials: I
authors.lastname: Lee
authors.forename: Carolyn K
authors.initials: CK
authors.lastname: Suzuki
mesh_terms: D049069:ATP-Dependent Proteases; D000251:Adenosine Triphosphatases / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D019556:COS Cells; D002460:Cell Line; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D004622:Embryo, Mammalian / Q000378:metabolism; D015870:Gene Expression; D018507:Gene Expression Regulation, Developmental; D005816:Genetic Complementation Test; D006360:Heat-Shock Proteins / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D009154:Mutation; D009841:Oligonucleotides / Q000378:metabolism; D010447:Peptide Hydrolases / Q000378:metabolism; D011485:Protein Binding; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D012697:Serine Endopeptidases / Q000235:genetics* / Q000378:metabolism; D013379:Substrate Specificity
chemical_list: D018076:DNA, Complementary; D004268:DNA-Binding Proteins; D006360:Heat-Shock Proteins; D009841:Oligonucleotides; D012333:RNA, Messenger; D010447:Peptide Hydrolases; D049069:ATP-Dependent Proteases; D012697:Serine Endopeptidases; D000251:Adenosine Triphosphatases