Liu H T, Hu Y H, Wang C T, Lin L Y
Institute of Radiation Biology, National Tsing Hua University, Hsinchu, Taiwan, ROC.
Comp Biochem Physiol B Biochem Mol Biol. 1996 Oct;115(2):209-14. doi: 10.1016/0305-0491(96)00118-6.
In this study, the nucleotide sequences of the displacement loop (D-loop) and the ribosomal RNA genes of mitochondrial DNA (mtDNA) were determined from a representative each of two genera of ducks, Cainina muschata and Anas platyrhynchos. The duck mtDNA shows a specific gene order at 5' upstream of D-loop (5'ND6-tRNA(Glu)-D-loop3') that is identical to chick mtDNA but is different from that of mammalian or amphibian (5' cytochrome b-tRNA(Thr)-tRNA(Pro)-D-loop3'). Nucleotide diversity is greatest in the D-loop while being most conserved in the 12S rRNA gene, as indicated from a sequence comparison between duck and chick mtDNA. A consensus sequence in the D-loop region, which may play influential roles in the regulation of transcription and replication of mtDNA, was found in both CSB-1 and repeated sequences of birds. Sequences of four tRNA genes in this region are also reported. Among them, tRNA(Glu) shows the greatest sequence divergence when different order of birds are compared.
在本研究中，测定了两种鸭属（疣鼻栖鸭和绿头鸭）各一个代表样本的线粒体DNA（mtDNA）置换环（D-loop）和核糖体RNA基因的核苷酸序列。鸭mtDNA在D-loop 5'上游呈现出特定的基因顺序（5' ND6 - tRNA（Glu）- D-loop3'），这与鸡的mtDNA相同，但与哺乳动物或两栖动物的不同（5' 细胞色素b - tRNA（Thr）- tRNA（Pro）- D-loop3'）。从鸭和鸡的mtDNA序列比较可知，核苷酸多样性在D-loop中最大，而在12S rRNA基因中最为保守。在鸟类的CSB - 1和重复序列中均发现了D-loop区域的一个共有序列，其可能在mtDNA转录和复制的调控中发挥重要作用。还报道了该区域四个tRNA基因的序列。其中，当比较不同鸟类顺序时，tRNA（Glu）显示出最大的序列差异。
