Neurodevelopmental role of a tRNA methyltransferase underlying intellectual disability

tRNA 甲基转移酶对智力障碍的神经发育作用

• 批准号: 10540878
• 负责人: Kimberly Rose R. Madhwani
• 金额: $ 4.78万
• 依托单位: BROWN UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-01 至 2024-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10540878
• 关键词: Address; Adverse effects; Affect; Alleles; Amino Acids; Animals; Anticodon; Antioxidants; Attenuated; Bioinformatics; Biological Models; CRISPR/Cas technology; Code; Codon Nucleotides; Communication; Data; Degenerative Disorder; Development; Development Plans; Disease; Drosophila genus; Drug Screening; Educational process of instructing; Educational workshop; Electrophysiology (science); Enzymes; Event; Family; Foundations; Gene Expression; Gene Expression Regulation; Genes; Genetic; Genetic Transcription; Genetic Translation; Global Change; Growth; Human; Image; Individual; Intellectual functioning disability; Laboratories; Lead; Ligase; Link; Mentors; Mentorship; Methylation; Missense Mutation; Modeling; Modification; Molecular; Mutation; Nerve Degeneration; Nervous system structure; Neurodegenerative Disorders; Neurodevelopmental Disorder; Neurologic Effect; Neurological Models; Neurons; Neurosciences; Oxidative Stress; Pathway interactions; Patients; Pharmacology; Phase; Phenotype; Pluripotent Stem Cells; Positioning Attribute; Proteomics; RNA Stability; Reactive Oxygen Species; Regulation; Research; Research Personnel; Research Project Grants; Role; Science; Selenocysteine; Side; Structure; Synapses; System; Testing; Therapeutic; Training; Transfer RNA; Translations; Uridine; Variant; Work; Yeasts; base; behavioral study; combat; experience; experimental study; induced pluripotent stem cell; insight; interest; mutant; nervous system development; nervous system disorder; neurodevelopment; polypeptide; post-doctoral training; pre-doctoral; response; screening; selenophosphate; selenoprotein; skills; small molecule; synaptogenesis; tRNA Methyltransferases; teacher; transcriptomics; treatment strategy

PROJECT SUMMARY Gene regulation at multiple levels is critical for nervous system development and function. A number of mutations leading to global dysregulation of gene expression have been found to disproportionately affect the nervous system, leading to neurodevelopmental and neurodegenerative disorders. Transfer RNAs (tRNAs), which recognize codons and add the appropriate amino acid to growing polypeptides, can dynamically regulate translation. tRNAs are heavily post-transcriptionally modified to regulate their structure, stability, and fidelity. ALKBH8 is one of two metazoan homologs of the yeast tRNA methyltransferase TRM9. Stop and missense mutations in human ALKBH8 have recently been shown to cause intellectual disability in four families. However, ALKBH8’s role in the nervous system remains unknown. To address this, I have generated null alleles in Drosophila and found that ALKBH8 regulates synapse formation. My preliminary data suggest ALKBH8 attenuates synaptic growth by limiting oxidative stress through the methylation of tRNA- selenocysteine, which yields the rare 21st amino acid selenocysteine for the synthesis of selenoproteins. In AIM 1, I will employ genetic, pharmacological, imaging, and bioinformatic approaches in Drosophila to define the links between ALKBH8, selenoproteins, and synaptic growth and investigate the impact of a human ALKBH8 mutation in the nervous system. In AIM 2, I will build on the skills gained during my dissertation work by expanding into human-derived pluripotent stem cells (iPSCs) to model neurological disorders and probe potential treatment strategies. The proposed experimental plan will provide mechanistic insight into how tRNA modifications regulate gene expression during nervous system development. The proposed training plan will provide me with the technical, academic, and professional skillset to thrive for the remainder of my predoctoral training and beyond as I transition into a postdoctoral position. Successful completion of the F99/K00 aims will place me in a unique position to investigate mechanisms underlying neurodevelopment disorders in two model systems with complementary strengths and identify potential therapeutic treatments for affected individuals.

项目摘要 多水平的基因调控对神经系统的发育和功能至关重要。一些 已经发现导致基因表达的整体失调的突变不成比例地影响了 神经系统，导致神经发育和神经退行性疾病。转移RNA（tRNA）， 它识别密码子并将适当的氨基酸添加到生长的多肽中， 翻译. tRNA被大量转录后修饰以调节其结构、稳定性和保真度。 ALKBH 8是酵母tRNA甲基转移酶TRM 9的两种后生动物同系物之一。停止和误解 最近研究表明，人类ALKBH 8突变会导致四个家庭的智力残疾。 然而，ALKBH 8在神经系统中的作用仍然未知。为了解决这个问题，我生成了null 等位基因，并发现ALKBH 8调节突触的形成。我的初步数据显示 ALKBH 8通过限制氧化应激通过tRNA甲基化来减弱突触生长- 硒代半胱氨酸，其产生用于硒蛋白合成的稀有的第21氨基酸硒代半胱氨酸。在AIM中 1，我将在果蝇中采用遗传学，药理学，成像和生物信息学方法来定义 ALKBH 8，硒蛋白和突触生长之间的联系，并研究人类ALKBH 8的影响 神经系统的突变在AIM 2中，我将在我的论文工作中获得的技能的基础上， 扩展到人源性多能干细胞（iPSC），以模拟神经系统疾病并探索 潜在的治疗策略。 拟议的实验计划将提供机制洞察如何tRNA修饰调控基因 在神经系统发育过程中的表达。拟议的培训计划将为我提供技术， 学术和专业技能，以茁壮成长，为我的博士前培训的其余部分和超越，因为我 过渡到博士后职位。成功完成F99/K 00目标将使我处于一个独特的 在两个模型系统中研究神经发育障碍的潜在机制， 互补优势，并确定潜在的治疗方法，为受影响的个人。