THE MITOCHONDRIAL-DNA MOLECULE OF DROSOPHILA-YAKUBA - NUCLEOTIDE-SEQUENCE, GENE ORGANIZATION, AND GENETIC-CODE
THE MITOCHONDRIAL-DNA MOLECULE OF DROSOPHILA-YAKUBA - NUCLEOTIDE-SEQUENCE, GENE ORGANIZATION, AND GENETIC-CODE
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DOI：
10.1007/bf02099755
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发表时间：
1985-01-01
影响因子：
3.9
通讯作者：
WOLSTENHOLME, DR
中科院分区：
文献类型：
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作者：
CLARY, DO;WOLSTENHOLME, DR
介绍了果蝇线粒体DNA （mtDNA）分子的16019个核苷酸对的序列。该分子包含2个rrna、22个trna、6个已鉴定蛋白[细胞色素b、细胞色素c氧化酶亚基I、II和III (COI-III)，以及atp酶亚基6和8]和7个推测蛋白（URF1-6和URF4L）的基因。复制起源于1077个核苷酸的区域，92.8%为a + T，缺乏大于123个核苷酸的开放阅读框。与所有哺乳动物mtDNA中发现的与第二链DNA合成起始相关的等效序列在亚库巴线粒体DNA中不存在。亚库巴线粒体基因中没有内含子，基因间核苷酸很少（0-31）。在yakuba和哺乳动物的mtdna中发现的基因是相同的，但在它们的排列和作为转录模板的分子互补链的相对比例上存在差异。虽然D. yakuba小线粒体rRNA和大线粒体rRNA基因的G和C含量非常低，并且比其他后生动物的rRNA基因短，但它们可以折叠成与哺乳动物线粒体rRNA的二级结构非常相似的二级结构。雅库巴线粒体tRNA基因，像它们的哺乳动物对应物一样，在序列上比非细胞器tRNA更可变。在线粒体蛋白基因ATG、ATT、ATA和在一个案例（COI）中ATAA似乎被用作翻译起始密码子。在这些基因中发现的唯一终止密码子是TAA。在yakuba线粒体遗传密码中，AGA， ATA和TGA特异性丝氨酸，异亮氨酸和色氨酸分别存在。在雅库巴线粒体蛋白基因中有59种意义密码子，但93.8%的密码子以A或t结尾，密码子与反密码子的相互作用可能包括G-A和C-A在摆动位置的配对。总结了支持A和T核苷酸在D. yakuba mtDNA分子中与这些核苷酸功能相容的所有位置都受到青睐的假设的证据。
The sequence of the 16,019 nucleotide-pair mitochondrial DNA (mtDNA) molecule of Drosophila yakuba is presented. This molecule contains the genes for two rRNAs, 22 tRNAs, six identified proteins [cytochrome b, cytochrome c oxidase subunits I, II, and III (COI-III), and ATPase subunits 6 and 8] and seven presumptive proteins (URF1-6 and URF4L). Replication originates within a regin of 1077 nucleotides that is 92.8% A + T and lacks any open reading frame larger than 123 nucleotides. An equivalent to the sequence found in all mammalian mtDNA that is associated with initiation of second-strand DNA synthesis is not present in D. yakuba mtDNA. Introns are absent from D. yakuba mitochondrial genes and there are few (0-31) intergenic nucleotides. The genes found in D. yakuba and mammalian mtDNAs are the same, but there are differences in their arrangement and in the relative proportions of the complementary strands of the molecule that serve as templates for transcription. Although the D. yakuba small and large mitochondrial rRNA genes are exceptionally low in G and C and are shorter than any other metazoan rRNA genes reported, they can be folded into secondary structres remarkably similar to the secondary structures proposed for mammalian mitochondria rRNAs. D. yakuba mitochondrial tRNA genes, like their mammalian counterparts, are more variable in sequence than nonorganelle tRNAs. In mitochondrial protein genes ATG, ATT, ATA, and in one case (COI) ATAA appear to be used as translation initiation codons. The only termination codon found in these genes is TAA. In the D. yakuba mitochondrial genetic code, AGA, ATA, and TGA specific serine, isoleucine, and tryptophan, respectively. Fifty-nine types of sense codon are used in the D. yakuba mitochondrial protein genes, but 93.8% of all codons end in A or T. Codon-anticodon interactions may include both G-A and C-A pairing in the wobble position. Evidence is summarized that supports the hypothesis that A and T nucleotides are favored at all locations in the D. yakuba mtDNA molecule where these nucleotides are compatible with function.