A tRNA synthetase is an amino acid sensor for TOR in plants

tRNA 合成酶是植物中 TOR 的氨基酸传感器

基本信息

批准号：
10795209
负责人：
Jacob O Brunkard
金额：
$ 7.34万
依托单位：
UNIVERSITY OF WISCONSIN-MADISON
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-05-01 至 2023-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10795209
关键词：
Affinity Chromatography Amino Acids Amino Acyl-tRNA Synthetases Arabidopsis Binding Biochemical Biological Assay Biological Models Biology Biomedical Research Catalysis Cells Complex Cues Development Disease EIF-2alpha Eukaryota Evolution Foundations Future Genetic Genomics Goals Growth Growth and Development function Health Heart Homeostasis Human In Vitro Investigation Knowledge Label Leucine Longevity Malignant Neoplasms Maps Mediating Mediation Metabolic Metabolic Diseases Metabolism Methodology Methods Modeling Molecular Morbidity - disease rate Mutate Mutation Nitrogen Nutrient Nutrient availability Outcome Pathway interactions Phosphotransferases Physiological Physiology Plants Protein Kinase Proteins Proteomics Regulation Reporting Reproducibility Role Signal Pathway Signal Transduction Signal Transduction Pathway Sirolimus Solid System Techniques Testing Therapeutic Transfer RNA Translations United States Variant Work age related detection of nutrient experimental study genetic approach human disease improved in vivo innovation leucine-tRNA mRNA Translation metabolomics mortality novel protein protein interaction sensor targeted treatment therapeutic target yeast two hybrid system

项目摘要

PROJECT SUMMARY TARGET OF RAPAMYCIN (TOR) is a deeply conserved protein kinase that regulates eukaryotic metabolism. TOR senses and integrates upstream signals, especially nutrient availability, to coordinate metabolism and promote growth only when conditions are favorable. TOR dysregulation causes or contributes to a broad range of human diseases, including cancers, age-related health disorders, and metabolic disorders, which are the major causes of morbidity and mortality in the United States. Therefore, a major goal for biomedical research is to develop therapeutic treatments that specifically target components of the TOR signaling network without broadly disrupting metabolism and homeostasis in healthy cells that rely on TOR. Recently, there have been significant advances to that goal with the discovery of several putative amino acid sensors for TOR. Conflicting reports about the relative contributions, importance, and molecular mechanisms of these sensors have stymied these advances, however. This project uses an innovative approach to bring fresh perspective to these ongoing debates by shifting focus to the other major eukaryotic lineage, plants. In my lab’s ongoing work to elucidate the TOR signaling network in plants, I discovered a novel amino acid sensor for TOR, an aminoacyl tRNA synthetase (aaRS). This aaRS is necessary to maintain TOR activity and sufficient to stimulate TOR in plant cells. Using a combination of biochemical, molecular, genetic, and systems-level approaches, I propose to precisely define how the aaRS activates TOR in plant cells through three independent aims. In Aim 1, I propose to mutate key enzymatic residues and structural features of the aaRS to determine the molecular features it requires to activate TOR. In Aim 2, I propose to map the signal transduction pathway mediating aaRS-TOR activation using robust orthogonal interactomic approaches. Putative signal transduction components will then be validated using reciprocal assays and functional genetics to comprehensively define how aaRS-TOR interactors contribute to TOR regulation. In Aim 3, I propose to establish the selective sensitivity of TOR for specific amino acids and determine whether the aaRS is a bona fide amino acid sensor for TOR. Taken together, these three aims will define the molecular mechanisms underlying the putative amino acid-aaRS-TOR signaling axis and open new directions for future research on metabolic regulation in eukaryotes. Moreover, this pathway will serve as a model for understanding how tRNA synthetases have evolved functions beyond translation in signal transduction pathways and illuminate how the complex TOR signaling network evolved to integrate diverse physiological cues in humans. Long-term, our findings will make significant contributions to a major goal of contemporary biomedical research: fine-tuning TOR signaling networks to improve and lengthen healthy human lifespans.

项目概要雷帕霉素靶标 (TOR) 是一种高度保守的蛋白激酶，可调节真核生物 TOR 感知并整合上游信号，特别是营养物质的可用性，以协调。仅当条件有利于 TOR 失调导致或时才促进新陈代谢和促进生长。导致多种人类疾病，包括癌症、与年龄相关的健康障碍，以及代谢紊乱是美国发病和死亡的主要原因。因此，生物医学研究的一个主要目标是开发专门的治疗方法 TOR 信号网络的目标成分，而不广泛破坏新陈代谢，依赖 TOR 的健康细胞的稳态最近取得了重大进展。目标是发现几种假定的 TOR 氨基酸传感器。这些传感器的相对贡献、重要性和分子机制阻碍了这些研究然而，该项目使用了一种创新方法，为这些问题带来了新的视角。通过将焦点转移到其他主要的真核谱系——植物上，正在进行的争论。在我的实验室正在进行的阐明植物中 TOR 信号网络的工作中，我发现了一种新的氨基 TOR 的酸传感器，一种氨酰 tRNA 合成酶 (aaRS) 该 aaRS 对于维持 TOR 是必需的。活性并足以刺激植物细胞中的 TOR。遗传和系统级方法，我建议精确定义 aaRS 如何激活 TOR 在目标 1 中，我建议突变关键的酶残基和 aaRS 的结构特征，以确定激活 TOR 所需的分子特征。 2，我建议使用稳健的方法来绘制介导aaRS-TOR激活的信号转导途径然后将验证假定的信号转导成分。使用相互分析和功能遗传学来全面定义 aaRS-TOR 相互作用因子在目标 3 中，我建议建立 TOR 对特定的选择性敏感性。氨基酸并确定 aaRS 是否是 TOR 的真正氨基酸传感器。总而言之，这三个目标将定义假定的氨基的分子机制 Acid-aaRS-TOR 信号轴，为未来代谢调控研究开辟新方向此外，该途径将作为了解 tRNA 合成酶如何合成的模型。已经进化出信号转导途径中翻译以外的功能，并阐明了长期来看，复杂的 TOR 信号网络能够整合多种生理信号。我们的研究结果将为当代生物医学研究的主要目标做出重大贡献：微调 TOR 信号网络以改善和延长人类健康寿命。