Regulation of cortical circuit formation by subcellular compartmentalization of mRNA translation

通过 mRNA 翻译的亚细胞区室化调节皮质回路形成

• 批准号: 10447581
• 负责人: John Froberg
• 金额: $ 7.17万
• 依托单位: HARVARD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-07-01 至 2023-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10447581
• 关键词: 3-Dimensional; Address; Affect; Axon; Axonal Transport; Behavior; Biochemical; Biological Process; Biology; Brain; Caliber; Categories; Cells; Cerebral cortex; Code; Complex; Contralateral; Cues; Data; Development; Distal; Ensure; Foundations; Fragile X Syndrome; Future; Genes; Genetic Translation; Growth Cones; Hour; Interneurons; Investigation; Laboratories; Measures; Messenger RNA; Molecular; Mus; Nature; Nerve Degeneration; Nervous system structure; Neuraxis; Neurodegenerative Disorders; Neurons; Output; Parents; Pathway interactions; Population; Post-Transcriptional Regulation; Process; Protein Biosynthesis; Proteins; RNA; RNA Processing; RNA-Binding Proteins; Regulation; Ribosomes; Role; Signal Transduction; Specificity; Structure; Synapses; Testing; Time; Transcript; Translating; Translational Regulation; Translations; Work; axon growth; axon guidance; differential expression; disease-causing mutation; frontotemporal lobar dementia-amyotrophic lateral sclerosis; in vivo; insight; neural circuit; neuronal cell body; novel; programs; protein TDP-43; public health relevance; relating to nervous system; ribosome profiling; synaptogenesis; trafficking; transcriptome; translatome

Project Summary/Abstract Cerebral cortex and other projection neurons extend axonal projections 103-105 times longer than their cell body diameters with exquisite precision. Growth cones (GCs) are specialized subcellular compartments that interpret axon guidance and target-derived signals, and carry out subtype-specific programs to ensure appropriate circuit and synapse formation. Because GCs extend so far from cell bodies that it takes hours to days to send molecules to them via axonal transport, GCs must be “semi-autonomous”. Local translation has been proposed as a mechanism for local control of growth cone function, but the types and diversity of locally translated mRNAs in vivo is largely unknown. More broadly, translational regulation in neurons is likely a crucial mechanism for properly establishing and maintaining long-range circuitry. Multiple neurodevelopmental (ex: Fragile X-Syndrome), and neurodegenerative (ex: ALS/FTD) diseases are caused by mutations in RNA binding proteins that both directly and indirectly disrupt several aspects of RNA processing, and culminate in altered translational output. My project addresses how translational regulation contributes to the development of subtype identity and cortical circuit formation by employing our newly-developed, low-input ribosome profiling approach to: 1) compare translational outputs and identify mRNAs in the somata that are differentially translated between multiple specific cortical projection neuron subtypes; 2) analyze the full landscape of local translation in callosal projection neuron (CPN) GCs to identify candidate regulators that are specifically locally translated in GCs; 3) functionally investigate novel, select locally GC-translated candidates in callosal projection neuron circuit formation. This project undertakes a relatively comprehensive, in vivo investigation of both subtype differences in translation, and local translation and its mechanisms in GCs. The data generated and concepts explored will provide a deep and rigorous foundation for understanding translational regulatory diversity and distinctions between neural subtypes, and the categories of mRNAs locally translated in GCs during circuit development. Beyond rigorously investigating the unique biology at the intersection of circuit formation, RNA trafficking, and translational regulation in distal neuronal subcellular compartments, it also has substantial

项目摘要/摘要 大脑皮层和其他投影神经元的轴突投影比其细胞体长103-105倍 直径具有独特精度。生长锥（GC）是专门的亚细胞室，解释了轴突 指导和目标衍生的信号，并执行特定于亚型的程序，以确保适当的电路和突触 形成。因为GC远离细胞体延伸，因此通过轴突将分子发送给它们需要数小时到几天 运输，GC必须是“半自治”。已经提出了本地翻译作为局部控制的一种机制 生长锥功能，但是体内局部翻译的mRNA的类型和多样性在很大程度上尚不清楚。更广泛地 神经元中的翻译调节可能是正确建立和维持远程的关键机制 电路。多个神经发育（EX：脆弱的X综合征）和神经退行性（EX：ALS/FTD）疾病是 由RNA结合蛋白中的突变引起，直接和间接破坏RNA加工的几个方面 并在变化的翻译输出中达到高潮。我的项目解决了翻译法规如何促进 通过采用我们新发达的低输入核糖体来发展亚型身份和皮质电路形成 分析方法：1）比较翻译的输出并识别somata中的mRNA，这些mRNA被不同翻译 在多个特定的皮质投射神经元亚型之间； 2）分析Calloss中本地翻译的完整景观 投影神经元（CPN）GC识别专门在GC中局部翻译的候选调节剂； 3） 在功能上调查了新颖的，在Calloss投射神经元电路形成中选择局部GC翻译的候选者。 该项目对两种亚型翻译的差异和相对全面的体内调查以及 局部翻译及其在GC中的机制。生成的数据和探索的概念将提供深刻而严格的 理解翻译监管多样性和神经亚型之间的区别的基础， 电路开发过程中GC中局部翻译的mRNA类别。除了严格调查独特之外 在电路形成，RNA运输和远端神经元亚细胞中转化调节的交集的生物学 车厢，它也有实质性的