Structure and function of nonmuscle myosins

非肌肉肌球蛋白的结构和功能

• 批准号: 10278968
• 负责人: KRISHNA CHINTHALAPUDI
• 金额: $ 42.54万
• 依托单位: OHIO STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-08-15 至 2026-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10278968
• 关键词: ATP phosphohydrolase; Actins; Address; Adopted; Architecture; Binding; Biochemical; Biological; Biological Assay; Biology; Blood; Cell Adhesion; Cell division; Cell physiology; Cells; Cellular biology; Computer software; Cryoelectron Microscopy; Cues; Cytoskeleton; Data; Defect; Development; Disease; Electron Microscopy; Engineering; Enzyme Activation; Enzymes; Equilibrium; Eukaryotic Cell; Filament; Fluorescence Microscopy; Foundations; Future; Generations; Goals; Health; Heart; Heart Diseases; Hematological Disease; Heterogeneity; Human; In Vitro; Kinetics; Knowledge; Length; Malignant Neoplasms; Measurement; Microfilaments; Modeling; Molecular; Molecular Conformation; Motor; Motor Activity; Mutation; Myosin ATPase; Myosin S-2; Nephritis; Neurologic; Nucleotides; Physiological Processes; Play; Process; Property; Protein Engineering; Proteins; Regulation; Research; Resolution; Role; Structure; Techniques; Testing; Textbooks; Therapeutic; Tissues; Work; X-Ray Crystallography; base; cell motility; computerized data processing; deafness; design; enzyme activity; flexibility; high resolution imaging; human disease; innovation; mechanotransduction; mutant; nervous system disorder; non-muscle myosin; novel; paralogous gene; programs; protein complex; sensor; tool

Project Summary A hallmark of eukaryotic cells is their ability to migrate, divide, adhere and respond to environmental cues. Nonmuscle myosin-2 (NM2) motors play an essential role in many aspects of these fundamental cellular processes by forming short bipolar filaments that interact with actin filaments. NM2 motors are binary switches that alter between inactive and active states depending on the cellular context. The precise control of NM2 motor activity is critical for its cellular function as master regulator of the actin cytoskeleton. Aberrant regulation due to mutations in NM2 paralogs contribute to a whole host of diseases including blood and neurological disorders, heart diseases, deafness, nephritis, and cancers. NM2-specific therapies are thus needed, yet the lack of basic knowledge about the structure and regulation of NM2 paralogs is a bottleneck to their development. We aim to develop a detailed structural and mechanistic understanding of how force generation by NM2 motors drive various cellular functions. Using innovative and interdisciplinary techniques including the state-of-the-art cryo- electron microscopy, X-ray crystallography, steady-state kinetics, in vitro motility assays and high-resolution fluorescence microscopy, we will systematically dissect the mechanisms of activation and regulation of NM2. To achieve this, in Aim 1, we will determine the major structural states in the ATPase cycle of NM2 motors to explain enzyme function. In Aim 2, we will determine a high-resolution cryo-EM structure of the inactive state of full- length NM2 to explain its molecular architecture. In Aim 3, we will study the consequences of abolishing the ability to form an inactive state on the dynamics of NM2 filaments in cells. Collectively, our studies will provide a deeper understanding of the structure, function and regulation of NM2. Importantly, this knowledge will advance our understanding of emergent NM2 functions in cells and thus, lay the foundation for future development of NM2-specific therapeutics.

项目摘要 真核细胞的标志是它们迁移，分裂，粘附和响应环境线索的能力。 非肌肉肌球蛋白2（NM2）电动机在这些基本细胞的许多方面起着至关重要的作用 通过形成与肌动蛋白丝相互作用的短双极细丝来进行过程。 NM2电动机是二进制开关 根据细胞环境，这种情况在非活动状态和活动状态之间发生了变化。 NM2电机的精确控制 活性对于其作为肌动蛋白细胞骨架的主要调节剂的细胞功能至关重要。由于 NM2旁系同源物中的突变会导致许多疾病，包括血液和神经系统疾病， 心脏病，耳聋，肾炎和癌症。因此需要NM2特异性疗法，但缺乏基本疗法 关于NM2旁系同源物的结构和调节的知识是其发展的瓶颈。我们的目标 对NM2电机驱动力的产生如何产生详细的结构和机械理解 各种细胞功能。使用创新和跨学科技术，包括最先进的冷冻 电子显微镜，X射线晶体学，稳态动力学，体外运动测定和高分辨率 荧光显微镜，我们将系统地剖析NM2激活和调节的机制。到 在AIM 1中实现这一目标，我们将在NM2电动机的ATPase周期中确定主要结构状态以解释 酶功能。在AIM 2中，我们将确定全部不活跃状态的高分辨率冷冻结构 长度NM2解释其分子结构。在AIM 3中，我们将研究废除的后果 能够在细胞中NM2丝的动力学上形成不活跃的状态。总的来说，我们的研究将提供 对NM2的结构，功能和调节的更深入了解。重要的是，这些知识将促进 我们对出现的NM2在细胞中功能的理解，因此为未来发展奠定了基础 NM2特异性疗法。