GENETIC APPROACHES TO PROTEIN-NUCLEIC ACID INTERACTIONS

蛋白质-核酸相互作用的遗传学方法

• 批准号: 6518937
• 负责人: PAUL R SCHIMMEL
• 金额: $ 37.5万
• 依托单位: SCRIPPS RESEARCH INSTITUTE, THE
• 依托单位国家: 美国
• 财政年份: 1977
• 资助国家: 美国
• 起止时间: 1977-03-01 至 2005-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6518937
• 关键词: Escherichia coli; aminoacid tRNA ligase; bacterial genetics; biochemical evolution; enzyme activity; gene mutation; genetic library; intermolecular interaction; site directed mutagenesis; structural biology; transfer RNA

DESCRIPTION: This project uses methods and logic of molecular biology and genetics to investigate two components of the translation apparatus that are responsible for the rules of the genetic code. These components--transfer RNAs (tRNAs) and aminoacyl tRNA synthestases-- appeared early in evolution and became essential for all life forms. The code is established in aminoacylation reactions, whereby each of the twenty amino acids is attached to its cognate tRNA that bears the anticodon triplet of the code for that amino acid. There typically is one distinct synthetase for each amino acid. In the proposed work, much effort is directed at using genetic approached to study how the fine structure recognition of amino acids is achieved by the tRNA synthetases. This high level of discrimination is essential for establishing and maintaining the accuracy of the code. For some of the enzymes, the cognate tRNA plays a key role in achieving this highly differentiated fine structure discrimination of closely similar amino acids. The role of the tRNA is to direct a misactivated amino acid from the active site to a second, editing site, where a potential error of aminoacylation is eliminated. Genetic approaches are proposed to explore the consequences in vivo of mutations in the center for editing, and to demonstrate the misincorporation of amino acids into proteins as they are synthesized in the cell. In further work, semi-artificial tRNA synthetases will be created and studied in vivo. This work is intended to provide insight into how specific systems of aminoacylation can be assembled from simple pieces. Finally, recent work has established other roles for tRNA synthetases in higher organisms, particularly in human cells. These roles are to be investigated further using genetic screens. Because tRNA synthetases are essential proteins, they are being pursued as targets for new classes of antibiotics. Moreover, the recent demonstration of novel roles for these proteins in cellular signaling mechanisms suggests that other heath-related applications will emerge as more basic information is obtained on these systems.

描述：该项目使用分子生物学的方法和逻辑， 遗传学研究翻译装置的两个组成部分， 负责遗传密码的规则。这些成分--转移RNA （tRNA）和氨酰tRNA合成酶-出现在进化的早期， 成为所有生命形式的必需品。密码是在氨酰化反应中建立的 反应，由此二十种氨基酸中的每一种都连接到其同源物上， 携带该氨基酸密码的反密码子三联体的tRNA。那里 通常是每种氨基酸的一种不同的合成酶。在拟议的工作中， 许多努力是针对使用遗传方法来研究如何罚款 氨基酸的结构识别通过tRNA合成酶实现。这 高度的歧视对于建立和维持 代码的准确性。对于某些酶，同源tRNA起着关键作用 在实现这种高度分化的精细结构区分中的作用 非常相似的氨基酸。tRNA的作用是引导一个被错误激活的 在一个实施方案中，所述方法包括从活性位点到第二编辑位点的潜在氨基酸转移，其中所述潜在氨基酸转移是通过从活性位点到第二编辑位点的潜在氨基酸转移进行的。 消除了氨酰化的误差。遗传学方法被提议用于 探索编辑中心突变的体内后果，并 证明了氨基酸错误地结合到蛋白质中， 在细胞中合成。在进一步的工作中，半人工tRNA合成酶将 在活体内进行研究这项工作的目的是提供深入了解 氨酰化的特定系统如何从简单的片段组装起来。 最后，最近的工作已经确定了tRNA合成酶在高等植物中的其他作用。 生物体，特别是人类细胞。这些角色有待调查 进一步使用基因筛选。 由于tRNA合成酶是必需蛋白质，因此它们被用作 新型抗生素的目标。此外，最近的示威活动， 这些蛋白质在细胞信号传导机制中的新作用表明， 随着更多的基本信息， 在这些系统上获得。