Physical mechanisms of 3D cell motility

3D 细胞运动的物理机制

• 批准号: 10000957
• 负责人: Ryan Petrie
• 金额: $ 32.3万
• 依托单位: DREXEL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2023-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10000957
• 关键词: 3-Dimensional; Abnormal Cell; Actomyosin; Affect; Anterior; Architecture; Automobile Driving; Biophysics; Cell Communication; Cell Nucleus; Cell Polarity; Cell-Matrix Junction; Cells; Cellular biology; Characteristics; Coupled; Cytoskeleton; Dermis; Diffusion; Disease; Elements; Environment; Extracellular Matrix; Extracellular Structure; Fibroblasts; Filament; Generations; Goals; Human; Integrins; Intermediate Filaments; Lobopodia; Measures; Mechanical Stress; Microfilaments; Molecular; Movement; Myosin Type II; Neoplasm Metastasis; Nonmuscle Myosin Type IIB; Normal Cell; Nuclear; Physiological Processes; Physiology; Primary Neoplasm; Process; Production; Protein Isoforms; Regulation; Research Project Grants; Signal Transduction; Specificity; Structure; Testing; Tissues; Traction; Tropomyosin; Tumor Cell Invasion; Vimentin; Work; base; cell behavior; cell motility; crosslink; design; directional cell; experimental study; insight; link protein; migration; neoplastic cell; novel; novel strategies; novel therapeutic intervention; novel therapeutics; physical property; plectin; polarized cell; pressure; response; therapy design; three dimensional structure; tumor; wound healing

Project Summary Cell movement through three-dimensional (3D) extracellular matrix (ECM) is an essential component of normal physiology and disease, including wound healing and tumor metastasis. Understanding how cells move through structurally diverse 3D matrices will be essential to design therapies aimed at controlling cell migration in the body. During 3D migration, both metastatic tumor cells and wound healing fibroblasts are faced with the same problem: how to efficiently move the bulky, stiff nucleus. While the power of actomyosin contractility is essential for cells to move their nuclei in 3D matrices, it is not understood how it is regulated by the ECM structure or physically coupled to the nucleus. An additional layer of complexity comes from the fact that the 3D matrix structure can govern actomyosin contractility to dictate the type of protrusions cells use to move (i.e. migratory plasticity). By understanding how the structure of the 3D ECM affects the physical properties of the nucleus and actomyosin contractility, we aim to create a conceptual framework to explain how and why human cells switch between distinct 3D migration mechanisms. We recently discovered that human cells moving in a linearly elastic 3D matrix rely on integrin-based cell-matrix adhesions and the power of actomyosin contractility to pull the nucleus forward, like a piston, and switch from using low-pressure lamellipodia to high-pressure lobopodial protrusions. This project will test the hypothesis that mechanical stress on the nucleus reprograms intracellular architecture and polarity to power the nucleus, and thereby the cell through 3D matrices. To achieve these goals, we will combine biophysical and cell biology approaches to measure mechanical stress on the nucleus and determine the molecular connections between discreet cytoskeletal elements required for high-pressure 3D motility. Aim 1 will manipulate the physical structures of the matrix and the nucleus and measure the ability of the cells to assemble and activate the nuclear piston mechanism. This approach will establish why the 3D matrix can reprogram cellular force production to switch cells to pressure-driven 3D migration. Aim 2 will identify the actomyosin machinery that is specifically activated by 3D matrix-cell interactions to generate pressure and govern migratory plasticity. These experiments will clearly distinguish the actomyosin filaments responsible for pulling the nuclear piston forward from those that respond to matrix stiffness by increasing traction force. Aim 3 will determine the mechanisms by which vimentin intermediate filaments transmit force to the nucleus to sustain intracellular polarization and directional cell movement in the narrow confines of the 3D matrix. These novel approaches will determine if the nucleus is a mechanosensor that responds to 3D matrix structure by governing actomyosin contractility and the mode of 3D cell migration. This enhanced understanding of the fundamental principles of directional 3D cell motility and migratory plasticity will lead to new therapeutic strategies to control normal and abnormal cell movement in the body.

项目摘要 细胞通过三维（3D）细胞外基质（ECM）的运动是正常的重要组成部分 生理和疾病，包括伤口愈合和肿瘤转移。了解细胞如何移动 通过结构上不同的3D矩阵对于设计旨在控制细胞迁移的疗法至关重要 在体内。在3D迁移期间，转移性肿瘤细胞和伤口愈合成纤维细胞均面临 同样的问题：如何有效地移动笨重的僵硬核。肌动蛋白收缩力的力量是 细胞在3D矩阵中移动其核至关重要，尚不理解它如何受到ECM的调节 结构或物理耦合到核。另一个复杂性来自3D 基质结构可以控制肌动球蛋白的收缩力，以决定细胞用于移动的突起的类型（即 迁移塑性）。通过了解3D ECM的结构如何影响 核和肌动蛋白的收缩力，我们旨在创建一个概念框架，以解释人类的方式以及为什么 细胞在不同的3D迁移机制之间切换。我们最近发现人类细胞在 线性弹性3D矩阵依赖于基于整合素的细胞矩阵粘附和肌动蛋白收缩力的力量 像活塞一样向前拉细胞核，然后从使用低压薄片转换为高压 叶虫突起。该项目将检验以下假设：核重编程的机械应力 细胞内结构和极性为细胞核供电，从而通过3D矩阵进行细胞。到 实现这些目标，我们将结合生物物理和细胞生物学方法来测量机械应力 在细胞核上，确定谨慎的细胞骨架元素之间所需的分子连接 高压3D运动。 AIM 1将操纵矩阵和核的物理结构，然后 测量细胞组装和激活核活塞机制的能力。这种方法会 确定为什么3D矩阵可以重新编程细胞力产生以将细胞转换为压力驱动的3D 迁移。 AIM 2将识别由3D矩阵细胞专门激活的肌动蛋白机械 相互作用以产生压力并控制迁徙的可塑性。这些实验将明确区分 肌动球蛋白丝负责将核活塞从对矩阵做出反应的核活塞拉开 通过增加牵引力来刚度。 AIM 3将确定波形蛋白中间的机制 细丝向核传播力，以维持细胞内极化和方向性细胞的运动 3D矩阵的狭窄范围。这些新颖的方法将确定核是否是机械传感器 通过管理肌动球蛋白的收缩力和3D细胞迁移的模式来响应3D矩阵结构。 对定向3D细胞运动和迁移的基本原理的这种增强的理解 可塑性将导致新的治疗策略，以控制体内正常和异常细胞运动。