Nanomagnetic-guided tau-centric protein transport in neurons

摘要 Tau蛋白对于健康的神经元功能至关重要，这取决于（i）稳健的空间组织 和稳定的微管网络和（ii）精确运输蛋白质和亚细胞 细胞器从索马到不同的神经元隔室。在其病理形式中，已知Tau 有助于阿尔茨海默病在细胞水平上的传播。精确控制和引导 Tau蛋白在神经元群体中的空间分布和功能是一个强大的工具， 潜在的发现一种策略，以非侵入性阻断阿尔茨海默病的进展。 然而，从技术上讲，这种方法仍然是一个挑战。在本提案中，我们将应对这一挑战 利用芯片上的并行纳米磁力刺激阵列， 一次操作一万个神经元中的细胞器， 精度在以前的研究中，我们采用这种技术，我们已经观察到Tau-5蛋白分布， 在24小时内从一侧大鼠皮层神经元定位到对侧，当受到 亚细胞力范围为4.5 pN至70 pN。力致动和 蛋白质运输和大小，形状，尺寸之间的相互作用的磁性结构占主导地位 人们对纳米磁力范围知之甚少。更好地理解机制和相互作用， 然而，对于在实验室中更广泛地采用该工具以及用于可植入设备至关重要。在这 我们将首先确定磁性元件的大小、形状和尺寸如何影响 在高时空精度下的纳米磁力刺激的幅度和方向性（SA 1）。 其次，我们将确定在tau中纳米磁力控制的时空机制， 着丝粒蛋白转运蛋白（SA 2）。已知胞内力可以作用于蛋白质， 与铁磁纳米颗粒相关，或在肌动蛋白丝上，或在微管网络上。这 导致三种可能的机制将tau中心蛋白导向磁性元件：（1） 直接通过拖动纳米颗粒，（2）间接通过微管网络动力学，或（3） 间接通过肌动蛋白信号传导。我们的实验将揭示或排除潜在的机制， 结果将大大推进我们对τ中心纳米磁力的基本理解 神经细胞功能

Abstract Tau proteins are critical for healthy neuronal function, which depends on (i) robust spatial organization and stabilization of the microtubules network and (ii) precise transportation of proteins and subcellular organelles from the soma to distinct neuronal compartments. In its pathological form, Tau is known to contribute to the propagation of Alzheimer’s disease at the cellular level. Precisely controlling and guiding the spatial distribution and function of Tau proteins in populations of neurons is a powerful tool, with huge potential for discovery of a strategy to non-invasively block the progression of Alzheimer’s disease. Technically this method, however, remains a challenge. In this proposal we will address this challenge with on-chip arrays of parallelized nanomagnetic force stimulation that can be targeted to the subcellular scale to manipulate organelles in ten thousand of neurons at a time with an unprecedented level of precision. In previous studies employing this technique, we have observed that Tau-5 protein distribution localized within 24 h from one side in rat cortical neurons to the opposing side when subjected to a subcellular force range of 4.5 pN to 70 pN. The underlying mechanism between forces actuation and protein transport and the interactions between size, shape, dimension of magnetic structures dominating nanomagnetic force ranges are poorly understood. A better understanding of mechanism and interaction, however, is critical for a greater adoption of this tool in the lab and for use in implantable devices. In this proposal we will first determine how size, shape and dimensions of magnetic elements impact the magnitude and directionality of nanomagnetic force stimulation at high spatiotemporal precision (SA1). Second, we will identify the spatiotemporal mechanisms underlying nanomagnetic force control in tau- centric protein transporting (SA2). It is known that intracellular forces can act either on proteins associated to ferromagnetic nanoparticles, or on actin filaments, or on the microtubules network. This results in three possible mechanisms to direct tau-centric proteins towards magnetic elements: (1) directly through dragging nanoparticles, (2) indirectly through microtubules network dynamics, or (3) indirectly through actin signaling. Our experiments will reveal or exclude potential mechanism and the outcome will significantly advance our fundamental understanding of nanomagnetic forces in tau-centric neuronal cell function.