Engineering external forces for manipulating cargo transport in live neurons

描述（由申请人提供） 摘要：轴突充当细胞体和突触之间有组织的物质运输的管道，这是神经元的功能和存活所必需的过程。通过广泛的遗传和生物化学研究，轴突运输缺陷，如轴突货物的积累，与一系列神经退行性疾病有关。然而，目前尚不清楚是否以及如何有缺陷的轴突运输可能在神经元变性的进展中发挥作用。遗传学和生物化学方法缺乏精确的控制何时何地货物积累将发生沿着轴突，这使得它很难查明的作用“运输缺陷”的过程中的神经元变性。 在这个提议中，我们建议设计磁力和光学力，专门阻止在捕获区域含有磁性或光学纳米颗粒探针的轴突货物的种群。物理上阻止货物将是干扰货物运输过程的最直接手段之一，然而，这在活细胞中具有技术挑战性。我们将使用先进的纳米纤维、成像技术和新型纳米粒子探针来克服这些挑战。在狭窄的轴突内部，停滞的货物将充当路障，以减缓其他不受外力影响的无探针货物的运输。这种力诱导的交通堵塞提供了新的方法来调查是否阻止轴突运输是足以诱导神经元变性和细胞过程如何响应轴突交通堵塞。 公共卫生相关性：阿尔茨海默病等与神经系统疾病有关的神经退行性疾病影响着数百万人的生活，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。这项研究的结果将促进我们对年龄相关神经元死亡的理解，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.