Xu X, Arnason U
Division of Evolutionary Molecular Systematics, Lund, Sweden.
Gene. 1994 Oct 21;148(2):357-62. doi: 10.1016/0378-1119(94)90713-7.
The sequence of the mitochondrial (mt) DNA of the horse (Equus caballus) was determined. The length of the sequence presented is 16,660 bp. This figure, however, is not absolute due to pronounced heteroplasmy caused by variable numbers of the motif GTGCACCT in the control region of different molecules. Boundaries of the 13 peptide-coding genes were determined by the presence of start and stop codons, and by analogy with other eutherian mtDNAs. Three genes (COIII, NADH3 and NADH4) were not terminated by a stop codon. Comparison among the peptide-coding genes of the horse and eight other mammals suggests that the boundaries of some mt genes should be redefined. The number of repeats in the control region was determined by sequencing 77 different clones (20 direct plus 57 PCR clones). The number of repeats ranged from 2 to 29. There was a pronounced overrepresentation of clones with many repeats (22-27). Very few clones had a repeat number that was close to the mean number of repeats.
测定了马（Equus caballus）线粒体（mt）DNA的序列。所呈现序列的长度为16,660碱基对。然而，由于不同分子控制区域中基序GTGCACCT数量可变导致明显的异质性，这个数字并非绝对。13个肽编码基因的边界通过起始密码子和终止密码子的存在以及与其他真兽亚纲线粒体DNA的类比来确定。三个基因（COIII、NADH3和NADH4）没有终止密码子。马与其他八种哺乳动物的肽编码基因之间的比较表明，一些线粒体基因的边界应重新定义。通过对77个不同克隆（20个直接克隆加57个PCR克隆）进行测序确定了控制区域中的重复次数。重复次数范围为2至29次。具有许多重复（22 - 27次）的克隆明显过多。很少有克隆的重复次数接近平均重复次数。
