Engineering external forces for manipulating cargo transport in live neurons

描述(由申请人提供) 摘要：轴突作为细胞体和突触之间有组织地运输物质的管道，这一过程对神经元的功能和生存至关重要。广泛的遗传学和生物化学研究表明，轴突运输缺陷，如轴突堆积，与一系列神经退行性疾病有关。然而，目前尚不清楚轴突运输缺陷是否以及如何在神经元变性的进程中发挥作用。遗传和生化方法缺乏对货物在轴突上何时何地堆积的精确控制，这使得很难准确地确定“运输缺陷”在神经元退化过程中的作用。在这项建议中，我们建议设计磁力和光力，使在捕获区域含有磁性或光学纳米颗粒探头的轴突货物群体具体停滞。物理上拖延货物将是扰乱货物运输过程的最直接手段之一，然而，在活细胞中这在技术上是具有挑战性的。我们将利用先进的纳米制造、成像技术和新型纳米粒子探测器来克服这些挑战。在狭窄的轴突内，停滞的货物将成为路障，以减缓其他不受外力影响的无探头货物的贩运。这种力诱导的交通堵塞为研究阻断轴突运输是否足以引起神经元变性以及细胞过程如何对轴突交通堵塞做出反应提供了新的途径。 公共卫生相关性：与年龄相关的神经退行性疾病，如阿尔茨海默病，影响数百万人的生活，并构成日益严重的公共卫生挑战。本研究旨在探讨轴突运输缺陷如何导致或促进这些神经退行性疾病的进展。这项研究的发现将促进我们对与年龄相关的神经元死亡的理解，并有助于治疗这些疾病的治疗干预。

DESCRIPTION (Provided by the applicant) Abstract: The axon acts as a conduit for organized transport of materials between the cell body and the synapse, a process that is essential for the function and survival of neurons. Defective axonal transport, such as accumulation of axonal cargoes, has been linked with a range of neurodegenerative diseases by extensive genetic and biochemical studies. However, it is still unclear whether and how defective axonal transport might play a role in the progression of neuronal degeneration. Genetic and biochemical approaches lack precise control over when and where the cargo accumulations will happen along the axon, which makes it difficult to pinpoint the role of ""transport defect"" in the process of neuronal degeneration. In this proposal, we propose to engineer magnetic and optical forces that specifically stall a population of axonal cargoes that contain magnetic or optical nanoparticle probes at the trapping area. Physically stalling the cargoes would be one of the most direct means to perturb a cargo transport process, which, however, are technically challenging in live cells. We will overcome those challenges using advanced nanofabrication, imaging techniques and novel nanoparticle probes. Inside the narrow axon, stalled cargoes will act as roadblocks to slow down the trafficking of other probe-free cargoes that are not affected by external forces. Such force-induced traffic jams afford new approaches to investigate whether blocking the axonal transport is sufficient to induce neuronal degeneration and how cellular processes response to axonal traffic blockage. Public Health Relevance: Age-related neurodegenerative diseases, such as Alzheimer's disease, impact the lives of millions and pose a growing public health challenge. This study aims to investigate how defective axonal transport might cause or contribute to the progression of those neurodegenerative diseases. The findings of this research will advance our understanding of age-related neuronal death and assist therapeutic interventions for the treatment of these disorders.