Regulating axon guidance through local translation at adhesions

通过粘连处的局部翻译调节轴突引导

• 批准号: 10587090
• 负责人: Kristy Welshhans
• 金额: $ 37.49万
• 依托单位: UNIVERSITY OF SOUTH CAROLINA AT COLUMBIA
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-04-01 至 2028-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10587090
• 关键词: Actins; Acute; Adhesions; Axon; Binding; Biological Assay; Brain; Complex; Coupled; Cues; Cytoskeletal Modeling; Cytoskeleton; Data; Development; Disease; Extracellular Matrix; Extracellular Matrix Proteins; Filopodia; Growth; Growth Cones; Health; Integrins; Knowledge; Laminin; Link; Location; Mediating; Messenger RNA; Methods; Microfilaments; Microtubules; Molecular; Movement; Mus; Nature; Nervous System; Nervous System Physiology; Neurons; Positioning Attribute; Process; Protein Biosynthesis; Protein Isoforms; Proteins; Regulation; Reporter; Research; RiboTag; Role; Signal Induction; Signal Pathway; Signal Transduction; Site; Structure; Synapses; Testing; Total Internal Reflection Fluorescent; Translating; Translational Regulation; Translations; axon growth; axon guidance; beta Actin; cell motility; experimental study; extracellular; mRNA Translation; nervous system development; nervous system disorder; neurodevelopment; neurotransmission; novel; response; synaptogenesis; trafficking

PROJECT SUMMARY The precise establishment of neuronal connectivity during development is critical for normal nervous system function. This research examines how growth cones, which are the pathfinding structures of the developing neuron, connect with their appropriate targets. External cues regulate neuronal connectivity formation by resulting in the activation of intracellular signaling pathways and ultimately, reorganization of the cytoskeleton and adhesions. This proposal focuses on understanding the molecular mechanisms linking extracellular signaling with intra-axonal local translation in the developing nervous system. Local translation in axonal growth cones is necessary for axon growth and guidance, however our understanding of how local translation functionally directs axon guidance is limited. We recently demonstrated that point contacts, adhesion sites within growth cones, are a strategic location for targeted local translation. Point contact adhesions directly regulate axon guidance by linking the extracellular matrix to the intracellular actin cytoskeleton and providing the force for growth cone movement. Thus, this finding is important because it suggests that local translation of certain mRNAs at adhesions are situated to have a maximal impact on axon guidance. Point contacts are likely a fundamental puzzle piece that has been missing from our understanding of how local translation functionally directs axon guidance. Accordingly, our hypothesis is that local translation of β-actin mRNA is necessary for point contact dynamics, and point contacts are localized organizing nodes for translational regulation. We will test this hypothesis by determining if locally translated β-actin is integrated into point contacts to direct axon guidance (Aim 1) and elucidating the signaling pathway through which extracellular matrix-induced signaling stimulates intra-axonal mRNA translation (Aim 2). Furthermore, we will resolve the suite of mRNAs that are locally translated in response to extracellular matrix proteins, and their relationship to point contacts (Aim 3). Completion of the proposed aims will break new ground by discovering the interactions between the extracellular matrix, point contacts and local translation in the regulation of axon guidance. This research will enable a broad, mechanistic understanding as to how mRNA trafficking and local translation contributes to the establishment of neuronal connectivity, and increase our knowledge about the complex nature of brain development.

项目摘要 发育过程中神经元连接的精确建立对于正常的神经系统至关重要 功能这项研究探讨了生长锥，这是发展中国家的寻路结构， 神经元，与其相应的目标连接。外部线索通过以下方式调节神经元连接的形成： 导致细胞内信号通路的激活，并最终导致细胞骨架的重组 和粘连。这项建议的重点是了解细胞外连接的分子机制， 在发育中的神经系统中轴突内局部翻译的信号传导。轴突中的局部翻译 生长锥是轴突生长和指导所必需的，但是我们对局部翻译的理解是 功能性地指导轴突引导是有限的。我们最近证明了点接触，粘连部位 在生长锥内，是有针对性的本地翻译的战略位置。点接触粘连 通过将细胞外基质连接到细胞内肌动蛋白细胞骨架并提供 生长锥运动的力量。因此，这一发现很重要，因为它表明， 位于粘连处的某些mRNA对轴突导向具有最大影响。很可能是点接触 我们对本地翻译功能的理解中缺少了一个基本的拼图， 指导轴突的引导。因此，我们假设β-actin mRNA的局部翻译是必要的， 对于点接触动力学，点接触是平移的局部组织节点， 调控我们将通过确定局部翻译的β-肌动蛋白是否整合到点， 接触直接轴突指导（目标1），并阐明细胞外 基质诱导的信号传导刺激轴突内mRNA翻译（Aim 2）。此外，我们将解决 一组响应细胞外基质蛋白而局部翻译的mRNA，以及它们与 点接触（目标3）。完成所提出的目标将通过发现相互作用来开辟新的领域。 细胞外基质之间，点接触和局部翻译在轴突的调控指导下进行。这 这项研究将使人们能够广泛地、机械地理解mRNA的运输和局部翻译是如何发生的。 有助于建立神经元连接，并增加我们对复杂的知识 大脑发育的本质