The complete nucleotide sequence of the mitochondrial genome of sugar beet (Beta vulgaris L.) reveals a novel gene for tRNACys(GCA)
The complete nucleotide sequence of the mitochondrial genome of sugar beet (Beta vulgaris L.) reveals a novel gene for tRNACys(GCA)
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DOI：
10.1093/nar/28.13.2571
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发表时间：
2000-07-01
影响因子：
14.9
通讯作者：
Mikami, T
中科院分区：
文献类型：
--
作者：
Kubo, T;Nishizawa, S;Mikami, T
我们测定了被子植物甜菜(Beta uggaris cv TK81-O)线粒体基因组的全序列。该基因组全长368 799个核苷酸，包含29个蛋白质、5个rRNA和25个tRNA基因，其中大部分还与拟南芥线粒体基因组共享，拟南芥是被子植物线粒体基因组中唯一一个完全测序的基因。然而，这里发现的四个基因(即rps 13 TRNF-GAA、ccb577和trnC2-gca)在拟南芥线粒体中缺失。此外，在拟南芥中发现的四个基因(ccb228、rpl2、rpl16和trnY2-gua)在甜菜中完全不存在或仅以严重截断的形式存在。内含子、重复序列、额外的读框和插入的外源序列(叶绿体、核和质粒DNA序列)对甜菜线粒体基因组的总体大小有重要影响。然而，55.6%的基因组没有明显的信息特征。我们发现了一个新的tRNA(Cys)基因(trnC2-GCA)，它与迄今在高等植物中报道的任何tRNA(Cys)基因没有序列同源性。有趣的是，这个tRNA基因实际上转录成了一个成熟的tRNA，而天然的tRNA(Cys)基因(trnC1-gca)很可能是一个假基因。
We determined the complete nucleotide sequence of the mitochondrial genome of an angiosperm, sugar beet (Beta vulgaris cv TK81-O). The 368 799 bp genome contains 29 protein, five rRNA and 25 tRNA genes, most of which are also shared by the mitochondrial genome of Arabidopsis thaliana, the only other completely sequenced angiosperm mitochondrial genome. However, four genes identified here (namely rps13 trnF-GAA, ccb577 and trnC2-GCA) are missing in Arabidopsis mitochondria. In addition, four genes found in Arabidopsis (ccb228, rpl2, rpl16 and trnY2-GUA) are entirely absent in sugar beet or present only in severely truncated form. Introns, duplicated sequences, additional reading frames and inserted foreign sequences (chloroplast, nuclear and plasmid DNA sequences) contribute significantly to the overall size of the sugar beet mitochondrial genome. Nevertheless, 55.6% of the genome has no obvious features of information. We identified a novel tRNA(Cys) gene (trnC2-GCA) which shows no sequence homology with any tRNA(Cys) genes reported so far in higher plants. Intriguingly, this tRNA gene is actually transcribed into a mature tRNA, whereas the native tRNA(Cys) gene (trnC1-GCA) is most likely a pseudogene.