Small Molecules that Activate Cytoprotective Functions of Tyrosyl-tRNA Synthetase

激活酪氨酰-tRNA 合成酶细胞保护功能的小分子

基本信息

批准号：
10221719
负责人：
Sajish Mathew
金额：
$ 22.35万
依托单位：
UNIVERSITY OF SOUTH CAROLINA AT COLUMBIA
依托单位国家：
美国
项目类别：
财政年份：
2014
资助国家：
美国
起止时间：
2014-07-10 至 2024-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10221719
关键词：
Active Sites Affect Alzheimer&apos s Disease Alzheimer&apos s disease model Alzheimer&apos s disease pathology Amino Acids Amino Acyl-tRNA Synthetases Amyloid beta-42 Amyloid beta-Protein Area Attenuated Behavioral Assay Binding Biological Assay Brain Career Choice Cell Nucleus Centers of Research Excellence Crystallization DNA Damage DNA Double Strand Break DNA Repair DNA Repair Gene DNA Repair Pathway Data Development Drug Targeting Enzymes Evolution Extramural Activities Funding Histologic Homeostasis Hydrogen Peroxide Immunoblotting In Vitro Isomerism Lead Metabolic Modeling Molecular Conformation Mus N-Methylaspartate Names Nature Neurodegenerative Disorders Neuronal Survival Pathway Neurons Nicotinamide adenine dinucleotide Nuclear Oxidative Stress Pathway interactions Penetration Phenols Poly(ADP-ribose) Polymerases Protein Biosynthesis Proto-Oncogene Proteins c-akt Publications Publishing Resveratrol Series Signal Transduction Signal Transduction Pathway Stress Structure Testing Therapeutic Tyrosine Tyrosine-tRNA Ligase Work base density design excitotoxicity in vitro Model in vitro activity in vivo in vivo evaluation mouse model nervous system disorder neuroprotection neurotoxicity novel novel drug class novel strategies oxidative damage small molecule targeted treatment trans-resveratrol

项目摘要

ABSTRACT Aminoacyl-tRNA synthetases (aaRSs) are enzymes that activate L-amino acids for protein synthesis. However, during evolution, aaRSs progressively accrued ‘moonlighting’ functions that are activated under conditions of diminished protein synthesis and that enable aaRSs to regulate metabolic homeostasis and modulate signal transduction pathways. In particular, Tyrosyl-tRNA synthetase (TyrRS) moves into the nucleus under stress conditions and facilitates DNA repair through poly-ADP-ribose polymerase 1 (PARP1) activation. PARP1, the central regulator of nicotinamide adenine dinucleotide (NAD+) signaling, senses and responds to DNA damage and activates DNA repair pathways. Unrepaired or erroneously repaired DNA double strand breaks (DSBs) in neurons are a major contributing factor in the development of a variety of neurological disorders including Alzheimer’s disease (AD). In particular, accumulation of amyloid β(Aβ), a hallmark of AD, exacerbates the accumulation of DSBs in neurons. Remarkably, PARP1 is downregulated in AD and the TyrRS-PARP1 pathway was shown to attenuate Aβ-induced neurotoxicity. Stimulation of this pathway could offer a new approach to the treatment of AD and other neurodegenerative diseases. We hypothesize that the L-tyrosine binding pocket of eukaryotic TyrRS can be targeted to design and develop small molecules named TyrRS- Targeting Compounds (TTCs), which will activate the moonlighting functions of TyrRS that stimulate DNA repair, and that such molecules will exert neuroprotective activities in AD-relevant models. In the first year of this project, we have designed and synthesized a series of TTCs on the basis of our work published in Nature, which demonstrated that the cis-isomer of resveratrol (RSV) binds to TyrRS and acts as an L-tyrosine antagonist, activating PARP1-dependent signaling cascades. Some of the newly synthesized TTCs have already shown neuroprotective activity in vitro. Mechanistic analysis indicated that the lead neuroprotective compound activates AKT and upregulates DNA repair proteins. In the remaining period, we will pursue the following Specific Aims. Under Aim 1, we will continue structure-based design and synthesis of TyrRS Targeting Compounds (TTCs) based on the cis-RSV-bound co-crystal structure of TyrRS and demonstrate that such molecules engage and affect their TyrRS target. Under Aim 2, we will determine the effect of TTCs on the survival of primary cortical neurons and TyrRS/PARP1-dependent DNA repair and signaling cascades. Under Aim 3, we will test the in vivo therapeutic potential of TTCs that show neuroprotection in vitro using 5XFAD mouse model of AD. The completion of these Aims will provide proof-of-principle data that would guide the eventual development of a new class of drugs that targets TyrRS to activate PARP1-dependent DNA repair in neurons, with potential applicability to AD and other neurodegenerative diseases that originate from accumulated DNA damage.

抽象的氨酰-tRNA 合成酶 (aaRS) 是激活 L-氨基酸以进行蛋白质合成的酶。在进化过程中，aaRS 逐渐积累了“兼职”功能，这些功能在以下条件下被激活：蛋白质合成减少，使 aaRS 能够调节代谢稳态和调节信号特别是，酪氨酰-tRNA 合成酶 (TyrRS) 在压力下进入细胞核。条件并通过聚 ADP 核糖聚合酶 1 (PARP1) 激活促进 DNA 修复。烟酰胺腺嘌呤二核苷酸 (NAD+) 信号传导的中枢调节因子，感知 DNA 损伤并作出反应并激活 DNA 通路修复中未修复或错误修复的 DNA 双链断裂 (DSB)。神经元是多种神经系统疾病发展的主要因素，包括尤其是阿尔茨海默氏病 (AD)，AD 的一个标志——淀粉样蛋白 β(Aβ) 的积累会使病情恶化。 DSB 在神经元中的积累值得注意的是，PARP1 在 AD 和 TyrRS-PARP1 中下调。研究表明，该途径可以减轻 Aβ 诱导的神经毒性。刺激该途径可以提供一种新的途径。我们勇敢地说，L-酪氨酸是治疗 AD 和其他神经退行性疾病的方法。可以靶向真核生物 TyrRS 的结合口袋来设计和开发名为 TyrRS- 的小分子靶向化合物 (TTC)，将激活 TyrRS 的兼职功能，刺激 DNA 修复，并且此类分子将在 AD 相关模型的第一年发挥神经保护活性。在这个项目中，我们根据我们在《自然》杂志上发表的工作，设计并合成了一系列TTC，证明白藜芦醇 (RSV) 的顺式异构体与 TyrRS 结合并充当 L-酪氨酸拮抗剂，激活 PARP1 依赖性信号级联反应，一些新合成的 TTC 具有体外已经显示出神经保护活性。机制分析表明，它具有先导神经保护作用。化合物激活 AKT 并上调 DNA 修复蛋白在剩下的时间里，我们将继续研究。遵循具体目标在目标 1 下，我们将继续基于结构的 TyrRS 设计和合成。基于 TyrRS 的顺式 RSV 结合共晶结构的靶向化合物 (TTC) 并证明这些分子参与并影响其 TyrRS 靶标，在目标 2 下，我们将确定 TTC 对它们的影响。原代皮质神经元的存活以及 TyrRS/PARP1 依赖性 DNA 修复和信号级联反应。在目标 3 下，我们将测试 TTC 的体内治疗潜力，这些 TTC 在体外具有神经保护作用 AD 的 5XFAD 小鼠模型的完成将提供可指导的原理验证数据。最终开发出一类新药物，以 TyrRS 为靶点，激活 PARP1 依赖性 DNA 修复在神经元中，可能适用于 AD 和其他源自神经退行性疾病的疾病累积的DNA损伤。