STRUCTURE AND MECHANISM OF RIBOSOMAL RNA IN THE RIBOSOME

将对大肠杆菌核糖体中的核糖体RNA进行研究 物理技术来确定它的三维结构和 确定其运作过程中结构变化的性质和程度。 这些实验将基于16s的三维模型 在当前授权期内获得的30s亚基中的rRNA。 将使用几种策略来获取结构信息和 监控内部结构；重点将放在使用 可以放置在特定rRNA位置的光化学试剂，因为 这些信息提供了有关选定地区的大量信息。这个 初步实验将集中在16S rRNA周围的结构上 序列位置560、700、790、900和1500 靠近信使核糖核酸解码区。这一区域对功能至关重要 和所获得的结果将区分 另一种rRNA折叠。当这个区域被解决时，更多的外围 将对各地区进行调查。 这项工作的具体目标是：1.确定三维 MRNA轨道下的16S rRNA的结构，包括三个 区域：在tRNA解码位置，在解码区域的出口侧 (16S rRNA结构域II的一部分)和解码的入口侧 区域(16S rRNA的530茎环区域)，2.确定影响 抗生素结合和16S rRNA高位突变 结构，3.确定16S rRNA高分子的构象变化 在tRNA结合过程中的有序结构，在与 启动因子IF3和在转位过程中，4.确定是否 在30s亚基中，mRNA作为其路径的一部分进行折叠，并影响 TRNA在这个可能的折叠上结合和易位。 核糖体是一个重要的研究对象，因为它具有 一种我们尚不知道其分子的普遍生化过程 细节。增加对核糖体的了解将增加我们的理解 关于RNA的催化能力，以及我们对RNA的一般知识 结构和核糖核蛋白结构。的一个重要方面。 拟议的研究表明，许多抗生素在人体内发挥作用 核糖体。有必要了解这些相互作用的性质 以及它们对核糖体的影响，如果要合理地设计 合成抗生素。

The ribosomal RNA in the Escherichia coli ribosome will be investigated by physical techniques to determine its three dimensional structure and to determine the nature and extent of structural change during its function. These experiments will be based on the three dimensional model of the 16S rRNA in the 30S subunit that was derived in the current grant period. Several strategies will be used to obtain structural information and monitor the internal structure; an emphasis will be on the use of photochemical reagents that can be placed at specific rRNA sites because these provide significant amounts of information about selected areas. The initial experiments will focus on the structure of the 16S rRNA around sequence positions 560, 700, 790, 900, and 1500 as these are located very close to the mRNA decoding region. This region is critical to the function of the subunit and the results obtained will distinguish between alternative rRNA foldings. When this region is solved, more peripheral regions will be investigated. The specific aims of the work are: 1. to determine the three dimensional structure of the 16S rRNA underlying the mRNA track, including three regions: at the tRNA decoding sites, at exit side of the decoding region (part of the 16S rRNA domain II) and on the entrance side of the decoding region (the 530 stem loop region of 16S rRNA), 2. to determine the effects of antibiotic binding and 16S rRNA mutations on the 16S rRNA higher order structure, 3. to determine conformational changes in the 16S rRNA higher order structure during tRNA binding, in the initiation complex with initiation factor IF3 and in the translocation process, 4. to determine if mRNA is folded as part of its path in the 30S subunit and the influence of tRNA binding and translocation on this possible folding. The ribosome is an important subject of investigation because it performs a universal biochemical process for which we do not yet know the molecular details. Increased knowledge of the ribosome will add to our understanding of the catalytic capacities of RNA, and to our general knowledge of RNA structure and ribonucleoprotein structure. An important aspect of the proposed studies is that many antibiotics exert their activity on the ribosome. It is necessary to understand the nature of these interactions and their affect on the ribosome if there is to be rational design of synthetic antibiotics.