鲤鱼线粒体tRNA^(Cys)基因和轻链复制起始区的结构分析

STRUCTURE ANALYSIS OF THE MITOCHONDRIAL tRNA^(Cys) GENE AND THE ORIGINAL REGION OF LIGHT-STRAND REPLICATION FROM CARP

我们测定了鲤鱼线粒体半胱氮酸tRNA 基因和轻链(L 链)复制起始区的核苷酸序列,绘制了半胱氨酸tRNA 三叶草形的二级结构以及L 链复制区的茎环结构。通过五种脊椎动物tRNA^(cya)基因的核苷酸序列分析发现,鲤鱼线粒体tRNA^(cya)基因有许多不同于细胞质tRNA^(cya)基因的不寻常的结构特点。鲤鱼线粒体L 链复制起始区含有36个碱基,复制起始区茎环结构中的茎含有11对碱基,而环则是由14个碱基组成。同其它10种脊椎动物L-链复制起始区的核苷酸序列比较发现,鲤鱼茎环结构中的茎序列是非常保守的,而环的序列及环的长度则变化较大。茎环结构可能在轻链复制中起着重要的作用。

In this study,we have determined thenucleotide sequences of the cysteine tRNAgene and the original region of light-strandreplication from carp(Cyprinus carpio L.)mitochondrion,which were further repre-sented respectively in cloverleaf secondarystructure and stem loop structure.By com-paring the nucleotide sequences of 5 verte-brate tRNA^(cys)genes,it is found that carpmitochondrial tRNA^(cys)gene have manyunusual structural features differing fromthose of cytoplasmic tRNA^(cys)gene.Thecarp mitochondrial original region of light-strand replication consists of 36 baseswhich include 11 base pairs in its stemand 14 bases in its loop.By making acomparison between the nucleotide sequen-ces of the carp original region of light-strand replication and those of other 10vertebrates,it is further found that stemsequence of carp is very conservative whileloop sequense is very variable.This resultindicates that stem structure may play animportant role in the replication of lightstrand.