Osinga K A, Tabak H F
Nucleic Acids Res. 1982 Jun 25;10(12):3617-26. doi: 10.1093/nar/10.12.3617.
The DNA sequence around the beginning of the genes coding for the large and small ribosomal RNAs in yeast mitochondria has been established. In order to determine the 5'-end points of the ribosomal RNAs, DNA fragments were labelled in vitro at a restriction site within each gene and hybridized with ribosomal RNA. The hybrids were then treated with S1 nuclease and the products analysed for size by gel electrophoresis. This enabled us to identify where in the determined DNA sequence the 21S ribosomal RNA and the precursor for 15S ribosomal RNA (15.5S rRNA) start, since both transcripts are initiated de novo (Levens et al. (1981) J.Biol.Chem., 256, 5226-5232). Comparison of the DNA sequences around the start points of transcription reveals the existence of a homologous stretch of 17 nucleotides. This conserved sequence may be an essential element of a promoter in mtDNA.
酵母线粒体中编码大、小核糖体RNA的基因起始部位周围的DNA序列已被确定。为了确定核糖体RNA的5'末端位置,在每个基因内的一个限制性位点对DNA片段进行体外标记,并使其与核糖体RNA杂交。然后用S1核酸酶处理杂交体,并通过凝胶电泳分析产物的大小。这使我们能够确定在已确定的DNA序列中21S核糖体RNA和15S核糖体RNA前体(15.5S rRNA)的起始位置,因为这两种转录本都是从头起始的(Levens等人,(1981年)《生物化学杂志》,256,5226 - 5232)。转录起始点周围DNA序列的比较揭示了一段17个核苷酸的同源序列的存在。这个保守序列可能是线粒体DNA中启动子的一个关键元件。