Hoffmann R J, Boore J L, Brown W M
Department of Zoology and Genetics, Iowa State University, Ames 50011-3223.
Genetics. 1992 Jun;131(2):397-412. doi: 10.1093/genetics/131.2.397.
The sequence of 13.9 kilobases (kb) of the 17.1-kb mitochondrial genome of Mytilus edulis has been determined, and the arrangement of all genes has been deduced. Mytilus mitochondrial DNA (mtDNA) contains 37 genes, all of which are transcribed from the same DNA strand. The gene content of Mytilus is typically metazoan in that it includes genes for large and small ribosomal RNAs, for a complete set of transfer RNAs and for 12 proteins. The protein genes encode the cytochrome b apoenzyme, cytochrome c oxidase (CO) subunits I-III, NADH dehydrogenase (ND) subunits 1-6 and 4L, and ATP synthetase (ATPase) subunit 6. No gene for ATPase subunit 8 could be found. The reading frames for the ND1, COI, and COIII genes contain long extensions relative to those genes in other metazoan mtDNAs. There are 23 tRNA genes, one more than previously found in any metazoan mtDNA. The additional tRNA appears to specify methionine, making Mytilus mtDNA unique in having two tRNA(Met) genes. Five lengthy unassigned intergenic sequences are present, four of which vary in length from 79 to 119 nucleotides and the largest of which is 1.2 kb. The base compositions of these are unremarkable and do not differ significantly from that of the remainder of the mtDNA. The arrangement of genes in Mytilus mtDNA is remarkably unlike that found in any other known metazoan mtDNA.
已测定出紫贻贝17.1千碱基（kb）线粒体基因组中13.9千碱基的序列，并推导了所有基因的排列方式。紫贻贝线粒体DNA（mtDNA）包含37个基因，所有这些基因都从同一条DNA链转录而来。紫贻贝的基因组成具有典型的后生动物特征，包括大小核糖体RNA基因、一套完整的转运RNA基因和12种蛋白质基因。蛋白质基因编码细胞色素b脱辅基酶、细胞色素c氧化酶（CO）亚基I - III、NADH脱氢酶（ND）亚基1 - 6和4L以及ATP合酶（ATPase）亚基6。未发现ATPase亚基8的基因。与其他后生动物mtDNA中的那些基因相比，ND1、COI和COIII基因的阅读框含有长延伸序列。有23个tRNA基因，比之前在任何后生动物mtDNA中发现的多一个。额外的tRNA似乎指定甲硫氨酸，这使得紫贻贝mtDNA在拥有两个tRNA(Met)基因方面独一无二。存在5个长的未分配基因间序列，其中4个长度在79至119个核苷酸之间变化，最大的为1.2 kb。这些序列的碱基组成不显著，与mtDNA的其余部分没有明显差异。紫贻贝mtDNA中的基因排列与任何其他已知后生动物mtDNA中的排列显著不同。
