Subcellular Mechanical Force Transduction

亚细胞机械力传导

• 批准号: 7033293
• 负责人: DANIEL H REICH
• 金额: $ 25.65万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-04-15 至 2008-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7033293
• 关键词: biological signal transduction; biomechanics; cell adhesion; cell line; cell motility; cytoskeleton; extracellular matrix; intracellular; magnetic field; mechanical stress; mechanoreceptors; microarray technology; nanotechnology; technology /technique development

DESCRIPTION (provided by applicant): This project focuses on the role that sub-cellular forces experienced at sites of adhesion between cells and their extracellular matrix play in regulating cell organization and function. The adaptive process by which cells spatially resolve and respond to such localized forces is critical to the adhesion remodeling required for cell motility, where cells reinforce specific adhesions while disassembling others. Previous work in this area has shown that focal adhesions assemble in response to forces applied to them, but because adhesion to extracellular matrix also induces biochemical signals that trigger cell contractility, it remains unclear whether forces applied to specific adhesions result in any mechanical crosstalk with the remaining adhesions distributed throughout the cell. This project will combine the expertise of 2 investigators to employ a new technique that simultaneously allows local mechanical stimulation of the adherent surface of a cell and spatially-resolved measurement of the local force fields generated throughout the cell in response to this stimulation. It is proposed that the relationship between local stimulation and global mechanical response is critical to the mechanical coordination within the cytoskeleton required for cell motility. 1 of the investigators has recently developed a technique wherein the deflections of an array of microfabricated posts report the cytoskeletal tension and local force fields generated by a cell attached to the array. In this project, nanoengineered magnetic material embedded in individual posts will be used to deform those posts, thereby exerting tunable subcellular mechanical stresses to attached cells, while the effects of the these stresses are simultaneously measured by the surrounding posts. Specific Aim 1 of the project will be to characterize the ability of the magnetic post device to apply well-defined forces at the nanonewton level to cells, to calibrate these forces, and to demonstrate the transmission of stresses to the cells. Specific Aim 2 will be to measure the global response of a cell to local forces through studies of changes in contractility and in the distribution of cellular forces, Specific Aim 3 will be to measure the non-local response of focal adhesions to locally applied forces, to determine whether focal adhesions re-distribute globally as a result of the distributed changes in cellular forces, and to determine how focal adhesion distributions vary as a function of the strength of a locally applied force. Development of this novel technique will lead to new understanding of how mechanical stresses are transduced by cells into an adaptive, coordinated cytoskeletal response, and will open a pathway toward new insights into the mechanisms of cell motility critical for inflammation, cancer metastasis, and tissue development.

描述（由申请人提供）：该项目重点研究细胞与其细胞外基质之间的粘附位点所经历的亚细胞力在调节细胞组织和功能中所发挥的作用。细胞在空间上解析和响应这种局部力的适应性过程对于细胞运动所需的粘附重塑至关重要，其中细胞在分解其他粘附的同时增强特定的粘附。该领域的先前工作表明，粘着斑会响应施加于其上的力而聚集，但由于与细胞外基质的粘附也会诱导触发细胞收缩性的生化信号，因此目前尚不清楚施加于特定粘连的力是否会导致与分布在整个细胞中的剩余粘连的任何机械串扰。该项目将结合两名研究人员的专业知识，采用一种新技术，同时允许对细胞粘附表面进行局部机械刺激，并对整个细胞响应这种刺激而产生的局部力场进行空间分辨测量。有人提出，局部刺激和整体机械反应之间的关系对于细胞运动所需的细胞骨架内的机械协调至关重要。其中一名研究人员最近开发了一种技术，其中微加工柱阵列的偏转报告了细胞骨架张力和附着在阵列上的细胞产生的局部力场。在该项目中，嵌入单个柱中的纳米工程磁性材料将用于使这些柱变形，从而对附着的细胞施加可调的亚细胞机械应力，而这些应力的影响由周围的柱同时测量。该项目的具体目标 1 是表征磁柱装置向细胞施加纳牛顿水平的明确力的能力，校准这些力，并演示应力向细胞的传递。具体目标 2 是通过研究收缩性和细胞力分布的变化来测量细胞对局部力的整体响应，具体目标 3 是测量粘着斑对局部施加力的非局部响应，以确定粘着斑是否由于细胞力的分布变化而全局重新分布，并确定粘着斑分布如何随着局部施加力的强度而变化。这项新技术的发展将带来对细胞如何将机械应力转化为适应性、协调的细胞骨架反应的新认识，并将为深入了解对炎症、癌症转移和组织发育至关重要的细胞运动机制开辟新途径。