Mechanical Regulation of Cell Adhesion by Dynamic Cytoskeletal Assemblies

项目摘要 动态细胞骨架组装体对细胞粘附的力学调控 上皮组织是由动态的粘附，细胞间连接，连接相邻的细胞 以维持组织凝聚力和屏障功能，还允许动态过程， 愈合和组织形态发生。肌动球蛋白内产生的收缩力 细胞骨架被传递到细胞-细胞连接处，以控制局部细胞的形状和运动， 塑造组织形态并启动控制细胞命运的下游信号通路。 了解细胞-细胞连接的生物物理特性是如何调节的， 对理解和治疗胚胎发育过程中的缺陷，组织 工程和转移性肿瘤的诊断和治疗。该提案利用了 细胞生物物理学、分子细胞生物学、活细胞成像、数学 模型和光遗传学来研究RhoA信号如何调节收缩力， 控制细胞形状并最终控制组织形态发生的细胞-细胞连接长度的变化。 我们提出实验来阐明力依赖过程如何调节肌动球蛋白 收缩性、膜重塑和RhoA信号相互反馈以控制连接 长度和长度的变化。我们通过整合分子细胞生物学 细胞骨架动力学和生物物理学的先进定量成像方法 测量.通过获得蛋白质的动力学和运动学（运动）特征， 水平的张力，我们确定机制的力量传递内的局灶性粘连和 肌动蛋白细胞骨架然后，我们与理论物理学家密切合作， 分析理论和模拟与我们的定量生物物理测量。这项工作 建立了一个生物物理的理解细胞粘附，张力和形状，最终，将 为组织形态发生的理论和模型提供框架， 理解复杂生理过程的能力。更一般地说， 在这项建议中开发的可以更普遍地应用于了解力敏感性如何 细胞骨架内的反馈共同促进细胞形态发生过程。这将 使得能够开发改进的疗法来治疗涉及组织稳态的疾病 目前仅通过治疗分子靶点仍然难以实现。

Project Summary Mechanical Regulation of Cell Adhesion by Dynamic Cytoskeletal Assemblies Epithelial tissue is built by dynamic adhesions, cell-cell junctions, that connect neighboring cells to maintain tissue cohesion and barrier function yet also allow dynamic processes like wound healing and tissue morphogenesis. Contractile forces generated within the actomyosin cytoskeleton are transmitted to cell-cell junctions to control the local cell shape and motions that sculpt tissue morphogenesis and initiate downstream signaling pathways that control cell fate. Understanding how the biophysical properties of cell-cell junctions are regulated has widespread implications for understanding and treating defects during embryonic development, for tissue engineering and the diagnosis and treatment of metastatic tumors. This proposal leverages innovative combination of cell biophysics, molecular cell biology, live cell imaging, mathematical modeling and optogenetics to investigate how RhoA signals regulate contractile forces to drive changes in cell-cell junction length that control cell shape and, ultimately, tissue morphogenesis. We propose experiments to elucidate how force-dependent process regulating actomyosin contractility, membrane remodeling and RhoA signaling feedback to each other to control junction length and length changes. We approach this problem by integrating molecular cell biology approaches with advanced quantitative imaging of cytoskeletal dynamics and biophysical measurements. By obtaining kinetic and kinematic (motion) signatures of proteins at varying levels of tension, we identify mechanisms of force transmission within focal adhesions and the actin cytoskeleton. We then collaborate closely with theoretical physicists to test the predictions of analytical theory and simulations with our quantitative biophysical measurements. This work builds a biophysical understanding of cell adhesion, tension and shape that, ultimately, will provide the framework for theories and models of tissue morphogenesis that will have predictive power in understanding in complex physiological processes. More generally, the strategies developed in this proposal can be applied more generally to understand how force-sensitive feedbacks within the cytoskeletal conspire to facilitate cell morphogenic processes. This will enable the development of improved therapies to treat diseases involved in tissue homeostasis that currently remain elusive by solely treating molecular targets.