FUNCTIONAL ROLE OF RIBOSOMAL RNA IN TRANSLATION

本研究的总体目标是确定 核糖体RNA（rRNA）的翻译机制。 具体项目 已经被设计用来分析来自 大肠埃希菌 这些项目将涉及两个相关领域：1） 基因组保守核苷酸的作用 翻译. 单个rRNA核苷酸的功能意义将 通过定点诱变和突变体表征进行分析 功能 具体而言，16 S rRNA的790区域中的突变将是 构建的目的是探索rRNA在蛋白质起始中的作用， 合成. 此外，涉及相同的790 区域和23 S rRNA的2755区域将测试双分子相互作用 核糖体亚基缔合模型。 2660地区的变化 也将分析23 S rRNA，以了解延伸因子 与rRNA相互作用; 2）三级结构和功能 rRNA内的相互作用位点。 几种高阶相互作用 基于rRNA序列的系统发育比较提出。 这些 将通过补偿性现场指导试验对现场进行测试 诱变 诱变方法将首先应用于拟定的 16 S rRNA的中心结构域中的假结和孤对相互作用。 随后，一个非正则孤对，这是建议形成在 23 S rRNA的肽基转移酶中心将被诱变。 在一起， 这些项目的结果将有助于确定 rRNA翻译 这反过来将大大增加我们的 理解RNA作为细胞中的动态功能分子。

The overall goal of this research is to determine the functional role of ribosomal RNA (rRNA) in the mechanism of translation. Specific projects have been designed to analyze the details of rRNA molecules from Escherichia coli. These projects will address two related areas: 1) The role of phylogenetically conserved nucleotides in the process of translation. The functional significance of single rRNA nucleotides will be analyzed by site-directed mutagenesis and characterization of mutant function. Specifically, mutations in the 790 region of 16S rRNA will be constructed to explore the role of rRNA in the initiation of protein synthesis. In addition, compensatory mutations involving the same 790 region and the 2755 region of 23S rRNA will test a bimolecular interaction model for ribosomal subunit association. Alterations in the 2660 region of 23S rRNA will also be analyzed to understand how elongation factors interact with rRNA; and 2) The structure and function of tertiary interaction sites within rRNA. Several higher order interactions have been proposed based on phylogenetic comparisons of rRNA sequences. These sites will be tested experimentally by compensatory site-directed mutagenesis. The mutagenic approach will be applied first to proposed pseudoknot and lone pair interactions in the central domain of 16S rRNA. Subsequently, a non-canonical lone pair which is proposed to form in the peptidyl transferase center of 23S rRNA will be mutagenized. Together, the results from these projects will help to define the functional role of rRNA in translation. This in turn will add significantly to our understanding of RNA as a dynamic functional molecule in the cell.