Structural Mechanisms of Cytoskeletal Force-Sensing

细胞骨架力传感的结构机制

• 批准号: 10382368
• 负责人: GREGORY M ALUSHIN
• 金额: $ 33.9万
• 依托单位: ROCKEFELLER UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-04-06 至 2025-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10382368
• 关键词: 3-Dimensional; Actin-Binding Protein; Actins; Adhesions; Architecture; Binding; Binding Proteins; Bioinformatics; Biological Assay; Biophysics; Body part; Cardiomyopathies; Cell physiology; Cells; Chemical Structure; Chemicals; Cryo-electron tomography; Cryoelectron Microscopy; Cues; Cytoskeleton; Data; Development; Disease; Drug Design; Drug Targeting; Elements; Environment; Event; Exposure to; F-Actin; F-actin-binding proteins; Filament; Foundations; Functional disorder; Goals; Health; Image Analysis; Intervention; Length; Malignant Neoplasms; Mechanics; Microfilaments; Modeling; Molecular; Molecular Conformation; Molecular Motors; Motor; Motor Activity; Mutation; Myosin ATPase; Outcome; Pathway interactions; Physiological; Polymers; Preparation; Process; Protein Region; Proteins; Proteome; Regulation; Research Project Grants; Resolution; Role; Sampling; Series; Side; Signal Pathway; Signal Transduction; Signaling Protein; Structure; Surface; System; Testing; Therapeutic; Vinculin; Weight-Bearing state; alpha catenin; base; calponin; cancer cell; cell behavior; cofilin; comparative; completed suicide; deep learning; design; detector; drug development; drug discovery; flexibility; fluid flow; human disease; immune function; in vivo; insight; knowledgebase; macromolecular assembly; mechanical force; mechanical signal; mechanotransduction; mutant; network architecture; protein structure; protein structure function; receptor; reconstitution; therapeutic development; therapeutic target; three dimensional structure

PROJECT SUMMARY Cells in the body perceive cues from their local environment, which control cellular behavior through a coordinated series of molecular events known as signaling. Signaling is critically important for telling a cell if it should grow and divide, migrate to a different part of the body, or commit suicide if it has completed its function or been irreparably damaged. Frequently, signaling processes are found to be working incorrectly in diseased cells. For instance, cancer cells divide and migrate out of control and ignore cues which should keep them in check. Signals come in multiple forms. Specific molecules bind and activate cognate receptor proteins in the cell, known as “chemical signaling”, which is broadly well-understood. Physical forces and the rigidity of a cell’s environment also elicit specific cell behaviors, but we have a comparatively poor understanding of how proteins transmit these “mechanical signals”. A significant fraction of successful drugs target protein molecules which operate in chemical signaling. The development of many such treatments was stimulated by determining the detailed three-dimensional chemical structures of the interactions between receptor proteins and the molecules which activate them, facilitating the design of drugs which precisely intervene in these processes. Despite its importance, efforts to therapeutically target mechanical signaling have been limited. The long-term goal of this research project is to visualize how forces modulate the three-dimensional structure of mechanical signaling proteins to activate them, in order to facilitate the development of drugs that block these changes. This proposal is specifically focused on understanding how cellular polymers (“filaments”) composed of the protein actin coordinate mechanical signaling. The cell contains many networks composed of actin filaments, myosin molecular motor proteins, and hundreds of other binding partners, which collectively generate and transmit diverse forces. We hypothesize that specific types of forces cause distinct physical rearrangements in actin filaments, which can be detected by other proteins in the cell through direct binding interactions. We will identify proteins which bind actin in a force-sensitive manner (Aim 1), focusing specifically on delineating the precise regions of the proteins which confer force-sensitivity. We will next visualize how side-wise bending forces (Aim 2) and length-wise tensile and compressive forces generated by myosin motor proteins (Aim 3) impact actin filament structure, hypothesizing these force regimes produce distinct rearrangements which can be discriminated by binding partners. In pursuit of these Aims, we are developing sample preparation and computational image analysis approaches to visualize the three-dimensional structure of actin polymers in the presence of mechanical forces with cryo-electron microscopy (cryo-EM). In addition to providing basic insights into how forces are perceived by cells through changes in protein structure, our studies will guide the development of precise molecular interventions into mechanical signaling processes governed by actin.

项目摘要 体内的细胞从其当地环境中感知线索，这些线索通过A控制细胞行为 协调的一系列分子事件被称为信号传导。信号传导对于告诉单元是否至关重要 应该成长和分裂，迁移到身体的另一部分，或者自杀 或不可弥补的损坏。经常发现信号传导过程在解散中工作不正确 细胞。例如，癌细胞划分和迁移失控，忽略应将其保持在内的线索 查看。信号有多种形式。特定的分子结合并激活细胞中的同源受体蛋白， 被称为“化学信号传导”，这是广泛理解的。物理力和细胞的刚度 环境也引起特定的细胞行为，但我们对蛋白质的了解相对较差 传输这些“机械信号”。大量的成功药物靶向蛋白质分子 在化学信号传导中运行。通过确定了许多此类治疗的发展 受体蛋白与分子之间相互作用的详细的三维化学结构 激活它们，促进精确干预这些过程的药物的设计。尽管有它 重要性，热门靶向机械信号的努力受到限制。这个长期目标 研究项目是为了可视化力如何调节机械信号的三维结构 蛋白质激活它们，以促进阻止这些变化的药物的发展。 该建议专门针对理解细胞聚合物（“丝”）如何由 蛋白质肌动蛋白坐标机械信号传导。该单元包含许多由肌动蛋白丝组成的网络， 肌球蛋白分子运动蛋白，以及数百个其他结合伴侣，它们共同产生和 传递多种力量。我们假设特定类型的力在 肌动蛋白丝，可以通过直接结合相互作用在细胞中的其他蛋白质检测到。我们将 鉴定以力敏感方式结合肌动蛋白的蛋白质（AIM 1），专门针对描述 会议力敏感性的蛋白质的精确区域。接下来，我们将可视化侧面弯曲力 （AIM 2）和肌球蛋白运动蛋白产生的长度拉伸和压缩力（AIM 3）撞击肌动蛋白 细丝结构，假设这些力度制定会产生不同的重排 受约束力的伙伴歧视。为了追求这些目的，我们正在开发样本准备和 计算图像分析的方法，可视化肌动蛋白聚合物的三维结构 具有冷冻电子显微镜（Cryo-EM）的机械力的存在。除了提供基本见解 细胞如何通过蛋白质结构的变化来感知力，我们的研究将指导 将精确的分子干预措施开发为由肌动蛋白控制的机械信号传导过程。