Alkemar Gunnar, Nygård Odd
RNA. 2003 Jan;9(1):20-4. doi: 10.1261/rna.2108203.
Eukaryotic 16S-like ribosomal RNAs contain 12 so-called expansion segments, i.e., sequences not included in the RNA secondary structure core common to eubacteria, archaea, and eukarya. Two of these expansion segments, ES3 and ES6, are juxtaposed in the recent three-dimensional model of the eukaryotic 40S ribosomal subunit. We have analyzed ES3 and ES6 sequences from more than 2900 discrete eukaryotic species, for possible sequence complementarity between the two expansion segments. The data show that ES3 and ES6 could interact by forming a helix consisting of seven to nine contiguous base pairs in almost all analyzed species. We, therefore, suggest that ES3 and ES6 form a direct RNA-RNA contact in the ribosome.
真核生物类16S核糖体RNA包含12个所谓的扩展片段，即那些不包含在真细菌、古细菌和真核生物共有的RNA二级结构核心中的序列。在真核生物40S核糖体亚基的最新三维模型中，其中两个扩展片段ES3和ES6是并列的。我们分析了来自2900多个不同真核生物物种的ES3和ES6序列，以寻找这两个扩展片段之间可能的序列互补性。数据显示，在几乎所有被分析的物种中，ES3和ES6可能通过形成一个由七到九个连续碱基对组成的螺旋而相互作用。因此，我们认为ES3和ES6在核糖体中形成了直接的RNA-RNA接触。
