putative precursor for the small ribosomal RNA from mitochondria of Saccharomyces cerevisiae

• Published in: Nucleic acids research 1981-03, Vol.9 (6), p.1351-1364
• Main Authors: Osinga, K.A, Evers, R.F, Laan, J.C. van der, Tabak, H.F
• Format: Article
• Language: English
• Subjects: Base Sequence; DNA Restriction Enzymes; DNA, Mitochondrial - genetics; Endonucleases; Mitochondria - metabolism; Molecular Weight; Mutation; Nucleic Acid Hybridization; RNA, Ribosomal - genetics; Saccharomyces cerevisiae; Saccharomyces cerevisiae - genetics; Single-Strand Specific DNA and RNA Endonucleases; yeasts
• ISSN: 0305-1048; 1362-4962
• DOI: 10.1093/nar/9.6.1351

We have characterized a putative precursor RNA (15.5S) for the 15S ribosomal RNA in mitochondria of Saccharomyces cerevisiae. Hybrids were formed with mitochondrial RNA and mtDNA fragments terminally labelled at restriction sites located within the gene coding for 15S ribosomal RNA and treated with S1 nuclease (Berk, A.J. and Sharp, J.A. (1977) 12, 721–732). Sites of resistent hybrids were measured by agarose gel electrophoresis and end points of RNAs determined. The 15.5S RNA is approximately 80 nucleotides longer than the 15S ribosomal RNA, with the extra sequences being located at the 5′-end. Both 15S ribosomal RNA and 15.5S RNA are fully localised within a 2000 base pair HapII fragment. This putative precursor and the mature 15S ribosomal RNA are also found in petite mutants which retain the 15S ribosomal RNA gene. The petite mutant with the smallest genetic complexity has its end point of deletion (junction) just outside the HapII site located in the 5′ flank of the 15S ribosomal RNA gene as determined by S1 nuclease analysis. This leaves a DNA stretch approximately 300 base pairs long where an initiation signal for mitochondrial transcription may be present.