title: Alteration of a mitochondrial tRNA precursor 5' leader abolishes its cleavage by yeast mitochondrial RNase P.
abstract: A mitochondrial specific RNase P is required to process 5' leaders from mitochondrial tRNA precursors in Saccharomyces cerevisiae. Experiments with a pair of mitochondrial pretRNAs(Asp) having leaders of different base composition suggest that this enzyme is unexpectedly sensitive to leader sequence or structure. Asp-AU (75% AU leader) is cleaved by the mitochondrial RNase P while Asp-GC (39% AU) is not. Both are substrates for E. coli RNase P. Partial nuclease digestions show that the tRNA portions of the two precursors differ in tertiary structure, while their 5' leaders differ in secondary structure. It is unusual for an RNaseP to have substrate specificity requirements which preclude processing of a pretRNA known to be a suitable substrate for an RNaseP from another species.
authors.affiliation: University of Louisville School of Medicine, Department of Biochemistry, KY 40292.
authors.forename: M J
authors.initials: MJ
authors.lastname: Hollingsworth
authors.forename: N C
authors.initials: NC
authors.lastname: Martin
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism; D001483:Base Sequence; D004722:Endoribonucleases / Q000378:metabolism*; D004926:Escherichia coli / Q000201:enzymology; D029968:Escherichia coli Proteins; D005656:Fungal Proteins / Q000378:metabolism; D008928:Mitochondria / Q000201:enzymology; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D012322:RNA Precursors / Q000235:genetics / Q000378:metabolism*; D012323:RNA Processing, Post-Transcriptional; D012331:RNA, Fungal / Q000235:genetics / Q000378:metabolism*; D012345:RNA, Transfer, Amino Acid-Specific / Q000378:metabolism*; D012349:RNA, Transfer, Asp / Q000235:genetics / Q000378:metabolism*; D043262:Ribonuclease P; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D013379:Substrate Specificity
chemical_list: D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D005656:Fungal Proteins; D012322:RNA Precursors; D012331:RNA, Fungal; D012345:RNA, Transfer, Amino Acid-Specific; D012349:RNA, Transfer, Asp; D004722:Endoribonucleases; D043262:Ribonuclease P; C470865:ribonuclease P, E coli