翻訳と辞書 Words near each other ・ Ribordone ・ Riboregulator ・ Ribose ・ Ribose 1,5-bisphosphate phosphokinase ・ Ribose 1-dehydrogenase (NADP+) ・ Ribose 5-phosphate ・ Ribose isomerase ・ Ribose repressor ・ Ribose-5-phosphate adenylyltransferase ・ Ribose-5-phosphate isomerase ・ Ribose-5-phosphate isomerase deficiency ・ Ribose-5-phosphate—ammonia ligase ・ Ribose-phosphate diphosphokinase ・ Riboside ・ Ribosomal binding site ・ Ribosomal DNA ・ Ribosomal frameshift ・ Ribosomal Intergenic Spacer analysis ・ Ribosomal L28e protein family ・ Ribosomal pause ・ Ribosomal protein ・ Ribosomal protein L10 leader ・ Ribosomal protein L13 leader ・ Ribosomal protein L19 leader ・ Ribosomal protein L20 leader ・ Ribosomal protein L21 leader ・ Ribosomal protein L4 ・ Ribosomal protein L5 ・ Ribosomal protein leader ・ Ribosomal protein S19 Dictionary Lists mini英和辞書 mini和英辞書 Webster 1913 Latin-English FOLDOC Wikipedia English ウィキペディア

翻訳と辞書　辞書検索 [ 開発暫定版 ] スポンサード リンク Ribosomal DNA ： ウィキペディア英語版 Ribosomal DNA Ribosomal DNA (rDNA) is a DNA sequence that codes for ribosomal RNA. Ribosomes are assemblies of proteins and rRNA molecules that translate mRNA molecules to produce proteins. As shown in the figure, rDNA of eukaryotes consists of a tandem repeat of a unit segment, an operon, composed of NTS, ETS, 18S, ITS1, 5.8S, ITS2, and 28S tracts. rDNA has another gene, coding for 5S rRNA, located in the genome in most eukaryotes. 5S rDNA is also present in tandem repeats as in ''Drosophila''.〔 In the nucleus, the rDNA region of the chromosome is visualized as a nucleolus which forms expanded chromosomal loops with rDNA. These rDNA regions are also called nucleolus organizer regions, as they give rise to the nucleolus. In the human genome there are 5 chromosomes with nucleolus organizer regions: the acrocentric chromosomes 13,14,15,21 and 22. == Sequence homogeneity of the repeat unit == In the large rDNA array, polymorphisms between rDNA repeat units are very low, indicating that rDNA tandem arrays are evolving through concerted evolution.〔 However, the mechanism of concerted evolution is imperfect, such that polymorphisms between repeats within an individual can occur at significant levels and may confound phylogenetic analyses for closely related organisms. 5S tandem repeat sequences in several ''Drosophila'' were compared with each other; the result revealed that insertions and deletions occurred frequently between species and often flanked by conserved sequences. They could occur by slippage of the newly synthesized strand during DNA replication or by gene conversion.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Ribosomal DNA」の詳細全文を読む スポンサード リンク 翻訳と辞書 : 翻訳のためのインターネットリソース Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.