Structural studies of ribosome regulation

核糖体调控的结构研究

• 批准号: 8080180
• 负责人: Christine M Dunham
• 金额: $ 27.93万
• 依托单位: EMORY UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-06-01 至 2015-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8080180
• 关键词: Address; Affinity; Amino Acids; Bacteria; Binding; Binding Sites; Biochemical; Biological; Cell physiology; Cells; Codon Nucleotides; Complement; Complex; DNA; Disease; Enzymes; Event; Gene Expression; Genetic; Genetic Code; Genetic Models; Genomics; Goals; Human; Laboratories; Life; Ligands; Link; Maintenance; Mediating; Messenger RNA; Methods; Molecular; Monitor; Mutation; Organism; Peptides; Process; Production; Protein Biosynthesis; Proteins; Quality Control; RNA; RNA Binding; Reading; Reading Frames; Regulation; Relative (related person); Resolution; Ribosomal RNA; Ribosomes; Role; Signal Transduction; Site; Structure; Testing; Transfer RNA; Translational Regulation; Translations; Yeasts; base; dalton; design; fitness; human disease; interest; mutant; novel; polypeptide; premature; prevent; public health relevance; release factor; research study; structural biology; translation factor

DESCRIPTION (provided by applicant): Ribosomes are the complex, cellular machinery responsible for the production of all proteins in every living organism. This 2.5 million Dalton enzyme contains three large RNAs and more than 50 proteins that form two asymmetric subunits and promote mRNA-directed translation of the genetic code. Accurate translation requires the precise synchronization of regulatory factors, messenger RNAs and transfer RNAs to produce a mature protein. Errors associated with translation are detrimental to gene expression and hence cellular function. Furthermore, consistent with the critical importance of error- free protein synthesis for proper cellular function, there are numerous examples where human disease is linked to alterations in this macromolecular machinery that monitors the accuracy of these events. The major question that underlies translational regulation is how the ribosome is able to distinguish errors from non-canonical three-base decoding and tRNA misreading from normal function. Our long-term goal is to understand how this large macromolecular machine on a molecular level identifies such errors and how this process impacts human disease. This long-term goal will be addressed here by testing the hypothesis that mRNA and tRNA interactions with the ribosome cause conformational changes that prevent errors either through suppression of the mRNA mutation or via a new and novel proofreading mechanism for quality control purposes. Two independent but complementary aims are proposed. Aim 1 seeks to understand how a novel class of mutant tRNAs interact with the ribosome to alter the three-base genetic reading frame and suppress errors. Aim 2 is designed to understand the structural basis of a new quality control mechanism resulting from tRNA:mRNA mismatch errors. These aims will be accomplished through a combination of structural biology of large, functional ribosomal complexes, biochemical and biophysical methods. PUBLIC HEALTH RELEVANCE: The goal of this project is to understand how the genetic code is regulated during translation from RNA to protein. We are interested in how cells have evolved ways to either prevent genomic errors or use a newly discovered quality control mechanism to avoid various disease states that can arise. )

描述（由申请人提供）：核糖体是复杂的细胞机器，负责生产所有生物体中的所有蛋白质。这种250万道尔顿的酶含有三个大的rna和50多种蛋白质，形成两个不对称亚基，促进遗传密码的mrna定向翻译。准确的翻译需要调节因子、信使rna和转移rna的精确同步才能产生成熟的蛋白质。与翻译相关的错误对基因表达和细胞功能是有害的。此外，与无错误蛋白质合成对正常细胞功能的关键重要性相一致，有许多例子表明，人类疾病与这种监测这些事件准确性的大分子机制的改变有关。翻译调控的主要问题是核糖体如何区分非规范三碱基解码的错误和正常功能的tRNA误读。我们的长期目标是了解这个大型大分子机器如何在分子水平上识别这些错误，以及这个过程如何影响人类疾病。这一长期目标将在这里通过测试mRNA和tRNA与核糖体的相互作用导致构象变化的假设来解决，这些构象变化通过抑制mRNA突变或通过一种新的校对机制来防止错误，以达到质量控制的目的。提出了两个独立但互补的目标。目的1旨在了解一类新的突变trna如何与核糖体相互作用以改变三碱基遗传阅读框并抑制错误。目的2旨在了解tRNA:mRNA错配错误导致的新的质量控制机制的结构基础。这些目标将通过大型功能性核糖体复合物的结构生物学、生化和生物物理方法的结合来实现。