Chao S, Sederoff R, Levings C S
Nucleic Acids Res. 1984 Aug 24;12(16):6629-44. doi: 10.1093/nar/12.16.6629.
The nucleotide sequence of the gene coding for the 18S ribosomal RNA of maize mitochondria has been determined and a model for the secondary structure is proposed. Dot matrix analysis has been used to compare the extent and distribution of sequence similarities of the entire maize mitochondrial 18S rRNA sequence with that of 15 other small subunit rRNA sequences. The mitochondrial gene shows great similarity to the eubacterial sequences and to the maize chloroplast, and less similarity to mitochondrial rRNA genes in animals and fungi. We propose that this similarity is due to a slow rate of nucleotide divergence in plant mtDNA compared to the mtDNA of animals. Sequence comparisons indicate that the evolution of the maize mitochondrial 18S, chloroplast 16S and nuclear 17S ribosomal genes have been essentially independent, in spite of evidence for DNA transfer between organelles and the nucleus.
已确定玉米线粒体18S核糖体RNA编码基因的核苷酸序列,并提出了二级结构模型。利用点阵分析比较了整个玉米线粒体18S rRNA序列与其他15个小亚基rRNA序列的序列相似性程度和分布。线粒体基因与真细菌序列以及玉米叶绿体序列有很大相似性,而与动物和真菌中的线粒体rRNA基因相似性较小。我们认为这种相似性是由于与动物的线粒体DNA相比,植物线粒体DNA的核苷酸分歧率较低。序列比较表明,尽管有证据表明细胞器与细胞核之间存在DNA转移,但玉米线粒体18S、叶绿体16S和细胞核17S核糖体基因的进化基本上是独立的。