Chen H C, Wintz H, Weil J H, Pillay D T
Department of Biological Sciences, University of Windsor, Ontario, Canada.
Nucleic Acids Res. 1989 Apr 11;17(7):2613-21. doi: 10.1093/nar/17.7.2613.
Three tRNA genes have been isolated from a genomic library of Arabidopsis thaliana: a tRNASer (GCU), a tRNATyr (GUA) and a tRNAGlu (UUC) genes. These genes are located closely on the same DNA fragment. The tRNASer and the tRNAGlu genes have both 99% sequence similarity with their mitochondrial counterparts from higher plants indicating that these three tRNA genes are mitochondrial. The tRNATyr gene shows a particular high sequence similarity with the mitochondrial tRNAPhe pseudogene from maize, and both genes are flanked by a tRNASer gene in the upstream region. Extensive sequence comparisons of the Arabidopsis thaliana mitochondrial sequence containing the three tRNA genes and the corresponding region from maize and soybean mitochondria have shown evidence that the tRNA Tyr gene has been generated from a mitochondrial tRNAPhe gene. The conversion was accomplished by three genetic events: a 4 base-pair deletion, a mutation and a recombination, which led to the transformation of the acceptor stem and the anticodon.
已从拟南芥基因组文库中分离出三个tRNA基因：一个tRNASer（GCU）、一个tRNATyr（GUA）和一个tRNAGlu（UUC）基因。这些基因紧密位于同一DNA片段上。tRNASer和tRNAGlu基因与其来自高等植物的线粒体对应基因均具有99%的序列相似性，表明这三个tRNA基因是线粒体基因。tRNATyr基因与玉米线粒体tRNAPhe假基因具有特别高的序列相似性，并且这两个基因在上游区域均侧翼有一个tRNASer基因。对包含这三个tRNA基因的拟南芥线粒体序列与来自玉米和大豆线粒体的相应区域进行的广泛序列比较表明，tRNATyr基因是由线粒体tRNAPhe基因产生的。这种转变是通过三个遗传事件完成的：一个4碱基对缺失、一个突变和一次重组，这导致了接受茎和反密码子的转变。
