Deciphering the Molecular Assembly Mechanism of Giant DNA Viruses

破译巨型DNA病毒的分子组装机制

基本信息

批准号：
10621855
负责人：
Chuan Xiao
金额：
$ 34.24万
依托单位：
UNIVERSITY OF TEXAS EL PASO
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-06-01 至 2025-04-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10621855
关键词：
Affect Algorithmic Software Architecture Binding Biological Biological Assay Biophysics Capsid Capsid Proteins Cells Chemistry Cognitive Computer Analysis Cryoelectron Microscopy DNA Viruses Disease Docking Electrons Equation Evolution Fiber Foundations Future Generations Human Image Image Analysis Individual Laboratories Lipids Maps Mathematical Model Simulation Mathematics Methods Minor Modeling Molecular Nobel Prize Pathway interactions Pattern Phase Play Pneumonia Positioning Attribute Process Proteins Publishing Regulation Research Resolution Role Structure Techniques Technology Thick Training Viral Viral Proteins Virion Virus Virus Assembly Virus Diseases Virus-like particle Visualization Visualization software biophysical analysis detector experience experimental study frontier high resolution imaging human disease human pathogen image reconstruction improved insight marine mathematical analysis molecular assembly/self assembly molecular dynamics multimodality nano new therapeutic target novel pathogenic virus prevent protein protein interaction rational design reconstruction self assembly simulation structural biology therapeutic development tool

项目摘要

Project Summary/Abstract Over the last two decades, many giant DNA viruses have been discovered, some of which are bigger than a small cell. How these giant viruses assemble their virion shell from thousands of simple protein building blocks so precisely is a mystery. However, the sheer size of these viruses poses a significant challenge to currently available techniques. This project will tackle this challenge by using a marine giant virus Cafeteria roenbergensis virus (CroV) as a model to decipher the assembly mechanism of giant viruses, and as an opportunity to develop technology to push the resolution limit of these gigantic structures to the atomic level. During the last five years, cryo-electron microscopy (cryo-EM) has become an increasingly powerful tool to study the structures of biological molecules at atomic resolution, earning its developers the 2017 Nobel Prize in Chemistry. We will collect higher quality images using state-of-the-art cryo-EM equipped with latest new hardware, such as energy filters, direct electron detectors and phase plates. Using these images together with new software algorithms, we will determine the structure of giant CroV to high resolution by image analyses and reconstruction. Structures of individual CroV proteins will also be solved to atomic resolution by cryo-EM using various methods and docked into the cryo-EM reconstructed maps. The resultant pseudo-atomic structure will allow characterization of the ultrastructural features and architecture of CroV, building the essential foundation to unravel the assembly of giant viruses. The structure information will be combined with classic biophysical, molecular dynamic simulation, mathematical modeling, and computational analyses to evaluate the novel assembly model of giant viruses. In the new assembly model, the protein shells of giant viruses are assembled continuously from the 5-fold vertices in an interesting spiral way instead of assembled from patches in a step-wise fashion previously assumed. Giant virus protein shell is assembled from protein building block similar to other viruses, including many human pathogens. Some giant viruses have been associated with human diseases such as pneumonia and cognitive functional change. Understanding these principles governing the assembly of giant viruses will improve the development of therapeutic agents to inhibit virus assembly, thus providing a new avenue for preventing and treating viral diseases in general. Elucidation of the molecular interactions that drive assembly of these giant viruses will also shed light on how to control protein-protein interactions effectively, facilitating the rational design of virus-like nanoparticles with a wide size range for biomedical and other nano-applications. Since some giant viruses are bigger than a small cell, techniques and methods developed in this project will push the limits of structural biology and provide new and useful tools to study even larger supramolecular assemblies and eventually the whole cell in the future.

项目摘要/摘要在过去的二十年中，已经发现了许多巨型DNA病毒，其中一些比一个大于小单元。这些巨型病毒如何从数千个简单蛋白质构建块中组装出其病毒座壳恰恰是一个谜。但是，这些病毒的巨大规模对当前构成了重大挑战可用技术。该项目将通过使用海洋巨型病毒自助餐厅来应对这一挑战 Roenbergensis病毒（CROV）是破译巨型病毒的装配机理的模型，作为一种模型开发技术将这些巨大结构的分辨率限制推向原子水平的机会。在过去的五年中，冷冻电子显微镜（Cryo-EM）已成为越来越强大的工具研究原子分辨率生物分子的结构，赢得了其开发商2017年诺贝尔奖化学。我们将使用配备最新新的新型冷冻EM收集更高质量的图像硬件，例如能量过滤器，直接电子检测器和相板。将这些图像与新的软件算法，我们将通过图像分析确定巨型CROV到高分辨率的结构和重建。单个CROV蛋白的结构也将通过冷冻EM求解为原子分辨率使用各种方法，并将其停靠到冷冻EM重建图中。由此产生的伪原子结构将允许表征Crov的超微结构特征和建筑，建造揭开巨型病毒组装的基础。结构信息将与经典的生物物理，分子动态模拟，数学建模和计算分析评估巨型病毒的新型装配模型。在新的组装模型中，巨型蛋白质壳病毒以有趣的螺旋方式从5倍的顶点连续组装而不是组装以先前假定的逐步方式从补丁程序中。巨型病毒蛋白壳是由蛋白质组装的类似于其他病毒的基础，包括许多人类病原体。一些巨型病毒已经与肺炎和认知功能变化等人类疾病有关。了解这些管理巨型病毒组装的原则将改善治疗剂的发展以抑制病毒组装，从而提供了一种新的途径，以预防和治疗病毒疾病。阐明驱动这些巨型病毒组装的分子相互作用也将阐明如何控制有效的蛋白质蛋白质相互作用，促进了具有广泛尺寸的病毒样纳米颗粒的合理设计生物医学和其他纳米应用的范围。由于某些巨型病毒比小细胞大该项目中开发的技术和方法将推动结构生物学的限制，并提供新的和有用的工具可以在将来研究更大的超分子组件，最终是整个细胞。