Ishida N, Hasegawa T, Takeda K, Sakagami M, Onishi A, Inumaru S, Komatsu M, Mukoyama H
Laboratory of Molecular and Cellular Biology, Japan Racing Association, Tokyo.
Anim Genet. 1994 Aug;25(4):215-21. doi: 10.1111/j.1365-2052.1994.tb00196.x.
The D-loop regions in equine mitochondrial DNA were cloned from three thoroughbred horses by polymerase chain reaction (PCR). The total number of bases in the D-loop region were 1114 bp, 1115 bp and 1146 bp. The equine D-loop region is A/T rich like many other mammalian D-loops. The large central conserved sequence block and small conserved sequence blocks 1, 2 and 3, that are common to other mammals, were observed. Between conserved sequence blocks 1 and 2 there were tandem repeats of an 8 bp equine-specific sequence TGTGCACC, and the number of tandem repeats differed among individual horses. The base composition in the unit of these repeats is G/C rich as are the short repeats in the D-loops of rabbit and pig. Comparing DNA sequences between horse and other mammals, the difference in the D-loop region length is mostly due to the difference in the number of DNA sequences at both extremities. The similarities of the DNA sequences are in the middle part of the D-loop. In comparison of the sequences among three thoroughbred horses, it was determined that the region between tRNA(Pro) and the large central conserved sequence block was the richest in variation. PCR primers in the D-loop region were designed and the expected maternal inheritance was confirmed by PCR-RFLP (restriction fragment length polymorphism).
通过聚合酶链反应（PCR）从三匹纯种马中克隆出马线粒体DNA的D环区域。D环区域的碱基总数分别为1114 bp、1115 bp和1146 bp。马的D环区域像许多其他哺乳动物的D环一样富含A/T。观察到了其他哺乳动物共有的大的中央保守序列块以及小保守序列块1、2和3。在保守序列块1和2之间存在8 bp马特异性序列TGTGCACC的串联重复，并且串联重复的数量在个体马匹之间有所不同。这些重复单元中的碱基组成富含G/C，就像兔子和猪的D环中的短重复序列一样。比较马与其他哺乳动物的DNA序列，D环区域长度的差异主要是由于两端DNA序列数量的差异。DNA序列的相似性存在于D环的中间部分。在比较三匹纯种马的序列时，确定tRNA(Pro)与大的中央保守序列块之间的区域变异最丰富。设计了D环区域的PCR引物，并通过PCR-RFLP（限制性片段长度多态性）证实了预期的母系遗传。
