Complex modifications of tRNA: regulatory roles and crosstalk with DNA metabolism

tRNA 的复杂修饰：调节作用以及与 DNA 代谢的串扰

• 批准号: 9134775
• 负责人: Peter C Dedon
• 金额: $ 37.76万
• 依托单位: UNIVERSITY OF FLORIDA
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-03-02 至 2019-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9134775
• 关键词: 7-deazaguanine; Address; Affect; Anabolism; Anti-Bacterial Agents; Anticodon; Award; Bacteria; Cell physiology; Cells; Cessation of life; Complex; DNA; DNA Damage; DNA Modification Process; DNA Repair; Data; Deinococcus radiodurans; Disease; Enzymes; Escherichia coli; Eukaryota; Exhibits; Family; Family member; Gene Expression; Genes; Genetic Epistasis; Goals; Health; Homeostasis; Human; Knowledge; Lead; Life; Link; Malignant Neoplasms; Mammals; Messenger RNA; Metabolism; Metals; Methods; Mission; Mitochondria; Modeling; Modification; Nucleic Acids; Nucleoside Q; Organism; Pathogenesis; Pathology; Pathway interactions; Phenotype; Physiological; Physiology; Play; Positioning Attribute; Process; Property; Proteins; RNA; Recruitment Activity; Regulation; Research; Research Support; Resistance; Role; Salmonella; Stress; System; Testing; Transfer RNA; Translations; Work; Yeasts; base; comparative genomics; genetic regulatory protein; in vivo; innovation; mutant; nervous system disorder; novel; paralogous gene; pathogenic bacteria; prevent; protein misfolding; repaired; research study; response; stem

 DESCRIPTION (provided by applicant): The anticodon stem loop (ASL) is critical for decoding properties of tRNA. The universal threonylcarbamoyladenosine (t6A) and the widespread 7-deazaguanosine derivative queuosine (Q) are two ASL modifications at positions 37 and 34, respectively. Our discovery of the biosynthesis pathways for these two complex modifications that had been "missing" for decades has opened the path to study the role of these modifications in vivo. The long-term goal of our research is to expand fundamental knowledge on the synthesis and function of complex tRNA modifications and related molecules, and to understand their roles in core cellular processes and physiology. The current application focuses on the in vivo role of t6A and Q. Because their pathways are complex and draw on primary metabolites and both these modifications have central roles in decoding, t6A and Q are ideal candidates for molecules that integrate metabolism and translation and could play unforeseen regulatory roles. Preliminary results suggest that the absence of t6A triggers an unfolded protein response in both yeast and Bacteria and that t6A affects the translation of specific proteins and this will be the focus of Aim 1. Preliminary phenotypic screens show that Escherichia coli mutants that lack Q have metal sensitivity or resistance phenotypes, and the role of this modification in how cells sense and adapt to metal stresses will be explored in Aim 2. In addition, it has recently been shown that RNA and DNA modifications pathways have much more in common than previously anticipated. Our unexpected discovery that Q precursors are inserted in DNA suggests that paralogs of Q synthesis enzymes have been recruited in DNA metabolism and this will be studied in Aim 3. Aim 4 will focus on the potential role in DNA repair of a paralog of the first enzyme of t6A synthesis. The approach is innovative because comparative genomic methods were used to guide the experimental effort, and this work is revealing new regulatory mechanisms linking metabolism and translation as well totally novel modifications of DNA. The proposed research is significant because it will advance our understanding of the role of critical tRNA modifications and novel DNA modifications in fundamental cellular physiology.

 描述（由应用提供）：反登起茎环（ASL）对于解码tRNA的特性至关重要。通用的三季兰卡氨基苯胺（T6A）和宽度7-二氮烷衍生物Queuosine（Q）分别在位置37和34处进行了两个ASL修饰。我们发现了数十年来“缺失”这两种复杂修饰的生物合成途径，为研究这些修饰在体内的作用开辟了道路。我们研究的长期目标是扩大有关复杂tRNA修饰和相关分子的合成和功能的基本知识，并了解它们在核心细胞过程和生理学中的作用。当前的应用侧重于T6a和Q的体内作用。由于它们的途径很复杂，并且借鉴了原代代谢物，并且这两种修饰都在解码中具有核心作用，T6A和Q是整合代谢和翻译的分子的理想候选者，并且可以发挥不可预见的法规绩效。 Preliminary results suggest that the absence of t6A triggers an unfolded protein response in both yeast and Bacteria and that t6A affects the translation of specific proteins and this will be the focus of Aim 1. Preliminary phenotypic screens show that Escherichia coli mutants that lack Q have metal sensitivity or resistance phenotypes, and the role of this modification in how cells sense and adapt to metal stresses will be explored in目标2。 此外，最近已经显示，RNA和DNA修饰途径的共同点比以前预期的要多得多。我们意想不到的发现，在DNA中插入了Q前体，这表明Q合成酶的旁系同源物已在DNA代谢中募集，这将在AIM 3中进行研究。IAM4将重点关注T6A合成的第一种酶的DNA修复的潜在作用。该方法具有创新性，因为使用比较基因组方法来指导实验努力，这项工作揭示了将代谢和翻译联系起来的新调节机制，以及完全新颖的DNA修饰。拟议的研究之所以重要，是因为它将促进我们对临界tRNA修饰的作用和新型DNA修饰在基本细胞生理学中的作用的理解。