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: 10677608
• 负责人: Kimberly Rose R. Madhwani
• 金额: $ 4.87万
• 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 2024-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10677608
• 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; Global Change; Growth; Homologous Gene; Human; Image; Individual; Intellectual functioning disability; Laboratories; Lead; Ligase; Link; Mentors; Mentorship; Methylation; Missense Mutation; Modeling; Modification; Molecular; Mutation; Nerve Degeneration; Nervous System; Neurodegenerative Disorders; Neurodevelopmental Disorder; Neurologic Effect; Neurological Models; Neurons; Neurosciences; Oxidative Stress; Pathway interactions; Patients; Phase; Phenotype; Pluripotent Stem Cells; Positioning Attribute; Postdoctoral Fellow; 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; behavioral study; candidate identification; combat; experience; experimental study; induced pluripotent stem cell; insight; interest; mRNA Translation; mutant; nervous system development; nervous system disorder; neurodevelopment; pharmacologic; polypeptide; post-doctoral training; posttranscriptional; pre-doctoral; response; restraint; 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.

项目概要 多个水平的基因调控对于神经系统的发育和功能至关重要。 已发现导致基因表达整体失调的突变会不成比例地影响 神经系统，导致神经发育和神经退行性疾病， 它识别密码子并向生长的多肽添加适当的氨基酸，可以动态调节 tRNA 在转录后经过大量修饰，以调节其结构、稳定性和保真度。 ALKBH8 是酵母 tRNA 甲基转移酶 TRM9 的两个后生动物同源物之一。 人类 ALKBH8 突变最近被证明会导致四个家庭的智力障碍。 然而，ALKBH8 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。 我的初步数据表明，果蝇中的等位基因发现 ALKBH8 调节突触形成。 ALKBH8 通过 tRNA 甲基化限制氧化应激，从而减弱突触生长 硒代半胱氨酸，在 AIM 中产生罕见的第 21 个氨基酸硒代半胱氨酸，用于合成硒蛋白。 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 ALKBH8、硒蛋白和突触生长之间的联系，并研究人类 ALKBH8 的影响 在 AIM 2 中，我将通过我的论文工作中获得的技能来发展。 扩展到人源多能干细胞（iPSC）以模拟神经系统疾病并进行探索 潜在的治疗策略。 拟议的实验计划将为 tRNA 修饰如何调节基因提供机制见解 拟议的培训计划将为我提供技术、 学术和专业技能在我剩余的博士前培训及以后的学习中蓬勃发展 成功完成 F99/K00 目标将使我处于一个独特的位置。 研究两个模型系统中神经发育障碍的潜在机制 互补优势并确定受影响个体的潜在治疗方法。