title: Mitochondrial asparaginyl-tRNA synthetase is encoded by the yeast nuclear gene YCR24c.
abstract: One of the open reading frames located on yeast Saccharomyces cerevisiae chromosome III, YCR24c, appeared to code for a protein of unknown function, but the predicted sequence showed similarity with asparaginyl-tRNA synthetase from Escherichia coli, with 38% amino acid identity. There is a putative mitochondrial targeting signal at the N-terminus of the YCR24c product. Northern blot analysis of total RNA from a wild-type strain sigma1278b confirmed that YCR24c was transcribed. Disruption of the chromosomal copy of YCR24c in a respiratory-competent haploid cell induced a petite phenotype, but did not affect cell viability. This respiratory-defective phenotype is typical for a mutation in a nuclear gene that induces a non-functional mitochondrial protein synthesis system. The protein encoded by YCR24c was expressed in Escherichia coli in a histidine-tagged form and isolated. The enzyme aminoacylated unfractionated Escherichia coli tRNA with asparagine. These results identified YCR24c as the structural gene for yeast mitochondrial asparaginyl-tRNA synthetase.
authors.affiliation: Unité de Microbiologie, Faculté Universitaire des Sciences Agronomiques de Gembloux, Belgium.
authors.forename: I
authors.initials: I
authors.lastname: Landrieu
authors.forename: M
authors.initials: M
authors.lastname: Vandenbol
authors.forename: M
authors.initials: M
authors.lastname: Härtlein
authors.forename: D
authors.initials: D
authors.lastname: Portetelle
mesh_terms: D000595:Amino Acid Sequence; D000604:Amino Acyl-tRNA Synthetases / Q000235:genetics* / Q000378:metabolism; D001226:Aspartate-tRNA Ligase; D004926:Escherichia coli; D005800:Genes, Fungal; D008928:Mitochondria / Q000201:enzymology*; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D012331:RNA, Fungal / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics; D012346:RNA, Transfer, Amino Acyl; D011994:Recombinant Proteins / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000235:genetics*
chemical_list: D012331:RNA, Fungal; D012333:RNA, Messenger; D012346:RNA, Transfer, Amino Acyl; D011994:Recombinant Proteins; D000604:Amino Acyl-tRNA Synthetases; D001226:Aspartate-tRNA Ligase; C029194:asparaginyl-tRNA synthetase