Investigating the role of neuronal SYNJ2 in mRNA transport and mitochondrial function

研究神经元 SYNJ2 在 mRNA 转运和线粒体功能中的作用

• 批准号: 10747226
• 负责人: Whitney Sharee Gibbs
• 金额: $ 5.2万
• 依托单位: BOSTON CHILDREN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-01-01 至 2023-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10747226
• 关键词: Advisory Committees; Alzheimer' s Disease; Axon; Back; Cell Differentiation process; Cells; Complex; Dendrites; Disease; Distal; Distant; Ensure; Goals; Half-Life; Health; Heterogeneity; Homeostasis; Human; Huntington Disease; Laboratories; Maintenance; Mediating; Membrane; Mentors; Messenger RNA; Mitochondria; Mitochondrial Proteins; Modeling; Mus; Mutate; Nerve Degeneration; Neurons; PINK1 gene; Parkinson Disease; Pathologic; Peripheral; Phase; Phosphotransferases; Physiological; Play; Process; Protein Biosynthesis; Proteins; RNA Binding; RNA Recognition Motif; Research; Role; SYNJ1 gene; Surface; Training; Transcript; Translations; Travel; Work; axon regeneration; axonal degeneration; career; diversity and inclusion; in vivo regeneration; innovation; meter; mitochondrial messenger RNA; neuronal cell body; neurotransmission; preservation

Project Summary Neurons critically depend on mitochondria function to maintain membrane excitability and execute complex functions, such as neurotransmission and plasticity. Neurons are highly differentiated cells that require large amounts of ATP to perform these functions and ensure long-term viability. The unique complexity of neurons is reflected by the extremely long segments that can extend up to a meter long and the functional heterogeneity for each neuronal compartment. The neuron has specialized mechanisms to transport mitochondria to the most distal parts to maintain proper neuronal function and survival. In turn, peripheral mitochondria rely on the transport of cellular components, such as mRNA and proteins, to sustain mitochondrial homeostasis without the need to travel back to the soma. The current proposal focuses on this aspect of mitochondrial maintenance, mitochondrial transcripts' ability to be trafficked to the axons for local translation, and how this influences mitochondrial and neuronal health and function. This project's significance is focused on PINK1, an essential mitochondrial kinase that is mutated in a hereditable form of Parkinson's disease. PINK1 protein will not survive transport down the axon because of its short half-life. To this end, our laboratory described an innovative mechanism by which mitochondria carry PINK1 mRNA on its surface to axons. Synaptojanin 2 (SYNJ2) was found to be responsible for tethering PINK1 mRNA to the mitochondria for axonal localization and local protein synthesis. The study of this neuronal-specific model suggests that the RNA binding function of SYNJ2 is required for PINK1-mediated processes (such as mitophagy); however, this has yet to be explored. The work planned in this proposal will explore the physiological and pathological consequence of disrupting the RNA binding function of SYNJ2, and; this unique approach is of critical importance for understanding mitochondrial mRNA transport and translation for preserving mitochondrial health. Thus, I hypothesize that Hypothesis: The RNA Recognition Motif of SYNJ2 causes PINK1 mRNA to colocalize with and be transported with mitochondria in a manner critical for PINK1 functions in axons and dendrites and thereby for maintaining neuronal health. I have assembled an advisory committee to provide conceptual and technical guidance as I explore the following Specific Aims: Aim 1: Examine the function of endogenous SYNJ2 and its RNA recognition motif in mice. Aim 2: Establish the role of peripheral SYNJ2 in mediating axonal mitochondrial function and neuronal health Aim 3: Investigate the impact of SYNJ2 RNA binding function in modulating axonal degeneration and regeneration in vivo. I have also developed a tailored diversity and inclusion training plan to execute during the mentored phase. The proposed studies and mentoring plans described in this proposal will provide me with a robust training platform to launch my independent academic research career.

项目概要 神经元严重依赖线粒体功能来维持膜兴奋性并执行复杂的任务 功能，例如神经传递和可塑性。神经元是高度分化的细胞，需要大量的 执行这些功能并确保长期生存能力的 ATP 量。神经元独特的复杂性是 通过可以延伸至一米长的极长片段和功能异质性来体现 对于每个神经元室。神经元有专门的机制将线粒体运输到 最远端部分维持适当的神经元功能和存活。反过来，外周线粒体依赖于 细胞成分（例如 mRNA 和蛋白质）的运输，以维持线粒体稳态，而无需 需要返回索玛。目前的提案重点关注线粒体的这个方面 维护，线粒体转录本被运输到轴突进行本地翻译的能力，以及这是如何实现的 影响线粒体和神经元的健康和功能。 该项目的意义在于 PINK1，这是一种重要的线粒体激酶，在 帕金森病的遗传形式。 PINK1 蛋白无法在沿着轴突的运输中存活下来，因为它 半衰期短。为此，我们的实验室描述了线粒体携带的创新机制 PINK1 mRNA 在轴突表面。 Synaptojanin 2 (SYNJ2) 被发现负责束缚 PINK1 mRNA 到达线粒体以进行轴突定位和局部蛋白质合成。本研究的 神经元特异性模型表明 SYNJ2 的 RNA 结合功能是 PINK1 介导的 过程（例如线粒体自噬）；然而，这还有待探讨。本提案中计划的工作将 探索破坏 SYNJ2 RNA 结合功能的生理和病理后果， 和;这种独特的方法对于理解线粒体 mRNA 转运和 维护线粒体健康的翻译。 因此，我假设：SYNJ2 的 RNA 识别基序导致 PINK1 mRNA 与线粒体共定位并以对轴突中 PINK1 功能至关重要的方式进行运输 和树突，从而维持神经元健康。我组建了一个咨询委员会 在我探索以下具体目标时提供概念和技术指导： 目标 1：检查 内源性SYNJ2及其RNA识别基序在小鼠中的功能。目标 2：确立外围设备的作用 SYNJ2 介导轴突线粒体功能和神经元健康目标 3：研究 SYNJ2 的影响 RNA 结合在体内调节轴突变性和再生中发挥作用。我还开发了一个 在指导阶段执行定制的多元化和包容性培训计划。拟议的研究和 本提案中描述的指导计划将为我提供一个强大的培训平台来启动我的 独立的学术研究生涯。