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)：本项目重点研究在细胞与其细胞外基质之间的粘附点所经历的亚细胞力在调节细胞组织和功能中所起的作用。细胞在空间上分解和响应这种局部作用力的适应性过程对于细胞运动所需的黏附重塑至关重要，在这种重塑中，细胞加强特定的黏附，同时分解其他黏附。该领域以前的工作表明，局部粘连是对施加的力做出反应的，但由于与细胞外基质的粘连也会诱导触发细胞收缩的生化信号，因此目前尚不清楚施加在特定粘连上的力是否会导致与分布在整个细胞中的剩余粘连发生机械串扰。该项目将结合2名研究人员的专业知识，采用一种新技术，同时允许对细胞附着表面进行局部机械刺激，并对整个细胞产生的局部力场进行空间分辨测量，以响应这种刺激。有人认为，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。一位研究人员最近开发了一种技术，其中微制桩阵列的偏转报告了连接到阵列上的细胞产生的细胞骨架张力和局部力场。在这个项目中，嵌入在单个桩中的纳米工程磁性材料将被用来使这些桩变形，从而对连接的细胞施加可调的亚细胞机械应力，而这些应力的影响同时由周围的桩来测量。该项目的具体目标1将是表征磁性桩装置在纳米牛顿水平向细胞施加明确定义的力的能力，校准这些力，并演示应力向细胞的传递。具体目标2将是通过研究细胞收缩性和细胞力分布的变化来测量细胞对局部力的整体反应，具体目标3将是测量局部粘连对局部作用力的非局部反应，确定局部粘连是否由于细胞力的分布变化而重新分布，以及确定局部粘连分布如何作为局部作用力的函数变化。这项新技术的发展将导致对细胞如何将机械应力转化为适应性的、协调的细胞骨架反应的新理解，并将为对炎症、癌症转移和组织发展至关重要的细胞运动机制开辟一条新的途径。