Structural Mechanisms of Cytoskeletal Force-Sensing

细胞骨架力传感的结构机制

基本信息

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
项目类别：
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

项目摘要

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.

项目概要体内的细胞感知来自局部环境的信号，这些信号通过一系列协调的分子事件（称为信号传导）对于告诉细胞是否存在至关重要。应该生长和分裂，迁移到身体的不同部位，或者在完成其功能后自杀或受到不可挽回的损害时，人们经常发现患病者的信号传导过程无法正常工作。例如，癌细胞会失控地分裂和迁移，并忽略那些应将它们留在体内的线索。检查信号有多种形式，特定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”，这是众所周知的物理力和细胞的刚性。环境也会引发特定的细胞行为，但我们对蛋白质如何影响细胞的了解相对较少传递这些“机械信号”的成功药物有很大一部分靶向蛋白质分子。许多此类治疗方法的发展是通过确定受体蛋白和分子之间相互作用的详细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。重要性，针对机械信号的治疗努力一直是有限的。研究项目是可视化力如何调制机械信号的三维结构蛋白质来激活它们，以促进阻止这些变化的药物的开发。该提案特别关注了解多孔聚合物（“长丝”）是如何组成的蛋白质肌动蛋白协调机械信号传导，细胞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伙伴，它们共同产生和我们追求特定类型的力会导致不同的物理重新排列。肌动蛋白丝，可以通过直接结合相互作用被细胞中的其他蛋白质检测到。识别以力敏感方式结合肌动蛋白的蛋白质（目标 1），特别关注描绘接下来我们将可视化赋予力敏感性的蛋白质的精确区域。（目标 2）和肌球蛋白运动蛋白产生的纵向拉伸力和压缩力（目标 3）影响肌动蛋白细丝结构，假设这些力状态产生不同的重排，可以为了实现这些目标，我们正在开发样品制备和技术。计算图像分析方法可视化肌动蛋白聚合物的三维结构除了提供基本见解外，还可以通过冷冻电子显微镜 (cryo-EM) 观察机械力的存在。关于细胞如何通过蛋白质结构的变化来感知力，我们的研究将指导开发对肌动蛋白控制的机械信号传导过程的精确分子干预。