5S rRNA: topology and function

描述（由申请人提供） 核糖体是极其精确的细胞蛋白质的核心组成部分 合成装置它的工作是快速准确地解码mRNA， 阅读三碱基密码子。“随着分子遗传学的出现， 可以创建和检查单个核糖体的突变体的影响， 不同核糖体相关功能的组分， 系统.这些新工具在经典生物化学方法中的应用是 从而更深入地了解许多核糖体 蛋白质和核糖体RNA（rRNA）在决定核糖体如何维持 翻译阅读框架。现在很清楚，rRNAs是 参与核糖体催化的反应，并且单个rRNA 积极参与不同的核糖体功能。然而，尽管它是 在整个进化过程中高度保守，无处不在的精确功能 5S rRNA基因尚未确定。过去，5S研究的主要障碍 rRNA是真核细胞具有多个染色体拷贝的事实， 5S rDNA基因排除了5S rRNA功能的任何遗传解剖， 或核糖体结构研究。我们已经克服了这一点 通过构建所有5S rRNA都表达于 质粒携带的克隆。利用该系统进行5SrRNA的全局诱变研究 揭示了新的表型，表明5S rRNA的新功能，我们 现在准备将5S rRNA的功能方面与其内部结构联系起来， 核糖体为此，我们得到了Olga A博士的帮助。Dontsova， 世界上最好的核糖体RNA结构实验室之一的负责人。拟议 合作将利用Dinman的遗传和生化优势， Dontsova博士拥有成熟的分子和生物化学专业知识的实验室 s组。这项建议的主要目的是确定 5S rRNA在其自身拓扑结构上的突变，以及在其他结构上的突变。 主要rRNA。该项目旨在建立，从这些影响， 突变体对5S rRNA结构的影响，通过它们对5S rRNA结构的影响， 与核糖体蛋白L5的结合，然后研究完整的核糖体蛋白L5， 60 S亚基和整个核糖体。这项研究将主要在 俄罗斯作为NIH资助#R 01-GM 62143的扩展。收集到的信息来自 这些研究将极大地扩展我们对 真核生物rRNA结构相互作用，并将提供科学的 社区对5S rRNA如何帮助确保 核糖体准确地将生物体的遗传信息翻译成 proteins.

DESCRIPTION (provided by applicant) The ribosome is the central component of an extremely accurate cellular protein synthetic apparatus. Its job is to rapidly and accurately decode mRNAs by reading three base "codons." With the advent of molecular genetics, it has been possible to create and examine the effects of mutants of individual ribosomal components on different ribosome-associated functions using specialized assay systems. The application of these new tools to classic biochemical methods are leading to a deeper understanding of the roles that many of the ribosomal proteins and ribosomal RNAs (rRNAs) play in determining how ribosomes maintain translational reading frame. It is now clear that the rRNAs are the central players in the reactions catalyzed by ribosomes, and that the individual rRNAs are actively involved in different ribosome functions. However, although it is highly conserved throughout evolution, the precise function of the ubiquitous 5S rRNA remains undetermined. In the past, the major barrier to studies of 5S rRNA was the fact that eukaryotic cells harbor multiple chromosomal copies of the 5S rDNA genes, which precluded any genetic dissection of 5S rRNA function, or structural studies within the context of the ribosome. We have overcome this hurdle by constructing a strain in which all 5S rRNAs are expressed from plasmid-borne clones. A global mutagenesis study of 5S rRNA using this system has revealed novel phenotypes indicative of new functions for 5S rRNA, and we are now poised to link functional aspects of 5S rRNA to its structure within the ribosome. To this end, we have enlisted the aid of Dr. Olga A. Dontsova, chief of one of the world's premier rRNA structural laboratories. The proposed collaboration will exploit the genetic and biochemical strengths of the Dinman laboratory with the proven molecular and biochemical expertise of Dr. Dontsova' s group. The broad aim of this proposal is to determine the effects of mutations in 5S rRNA on its own topology, and on the structures of the other major rRNAs. The project is designed to build up, from the effects of these mutants on the structure of 5S rRNA alone, through their effects on its association with ribosomal protein L5, and then to studies on intact ribosomal 60S subunits and whole ribosomes. This research will be done primarily in Russia as an extension of NIH grant # R01-GM62143. The information gleaned from these studies will represent a tremendous expansion of our knowledge of eukaryotic rRNA structural interactions, and will provide the scientific community with an entirely new understanding of how 5S rRNA helps to ensure that ribosomes accurately translate an organisms' genetic information into proteins.