TIM Protein-Mediated Ebola Virus-Host Cell Adhesion: Experiments and Models

TIM 蛋白介导的埃博拉病毒-宿主细胞粘附：实验和模型

基本信息

批准号：
1804117
负责人：
Anand Jagota
金额：
$ 25.68万
依托单位：
Lehigh University
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2018
资助国家：
美国
起止时间：
2018-07-01 至 2022-06-30
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1804117&HistoricalAwards=false
关键词：
TIM Protein Mediated Ebola Virus

项目摘要

Viruses cause diseases ranging from the common cold to the deadly and highly infectious Ebola disease. Their "modus operandi" is to enter healthy cells, often like a Trojan Horse, by hijacking normal physiological processes, tricking the cell to let them in. For this reason, a principal difficulty in designing therapies against viruses lies in the fact that attempts to stop them from entering a cell are also likely to affect normal physiological processes. For example, the Ebola virus infects healthy cells by disguising itself as debris (wastes or remains) from dead cells. Healthy cells whose normal function is to clear up this debris mistakenly take up Ebola and are thus infected. But there are always some differences between a virus and debris particles suggesting that, if studied carefully, it might be possible to design therapies that can block specific virus entry while leaving normal physiological processes essentially intact. In order to be successful in this attempt, it is necessary to understand virus uptake processes in quantitative detail both experimentally and theoretically, and particularly the latter, which is the main goal of this project. Building on separate studies that use microscope based technologies to measure binding forces between molecules, the focus of this project is to develop understanding of the behavior of collections of adhesion molecules (proteins on cell surfaces that cause cells to bind to other cells or particles), and ultimately to develop a predictive model for how an entire virus particle attaches to a cell prior to its uptake. An important part of this work is modeling the deformation of virus and cell particles in order to quantitatively measure their properties. If successful, this project will contribute to establishing an experimentally validated, quantitative connection between biology based models for virus entry into cells and the properties of the virus and the cell. The interdisciplinary nature of this research program will provide an excellent educational and research opportunity for graduate and undergraduate students. Working with the Da Vinci Science Center in Allentown, the investigators will design a new exhibit demonstrating the physical and mechanical details of virus uptake and how its study could lead to potential therapies or a cure. (The Da Vinci Science Center is an independent non-profit organization that promotes hands-on science learning through inquiry, highlights vibrant and important career opportunities in science available to every young person, and encourages all people to be curious and creative.) The goal of this project is to establish an experimentally informed predictive and quantitative model of the Ebola Virus (EBOV)-host cell interactions at the molecular through single-virus levels. While EBOV-host cell attachment has been shown to depend critically on the molecular biophysics of interaction between receptors on the cell surface and the outer coat of the virus, the quantitative understanding essential for guiding the development of therapies that would prevent EBOV from attaching to, and thus from entering a cell, is completely lacking. Recent work has established the importance of TIM family proteins and the geometry and mechanical properties of its mucin-like stalk domain (MLD). Building on these recent findings, further progress can be made by using experimental and theoretical molecular biophysics to uncover a quantitative understanding of the molecular, cellular, and biophysical mechanisms of EBOV attachment to a host cell. Building on separate studies that utilize single-molecule force spectroscopy to characterize experimentally how TIM family proteins interact with EBOV, this project will develop biophysical models that show how single-molecule biomechanical properties, and how the properties of the MLD, such as its length, rigidity, and charge density, control TIM mediated cellular/viral membrane adhesion and engulfment. The model will be developed in three phases. 1) At the Intermolecular Scale, the adhesion between a single TIM-1 and the viral membrane is studied using coarse-grained Brownian Dynamics Models to predict interaction potentials. 2) At the Intermediate Scale, the glycocalyx will be added to the cell surface and glycoproteins will be added on the virus surface to establish the role of the mechanical properties of the MLD stalk, using a course grained model solved with Brownian Dynamics at 300K. 3) At the Mechanics of Whole Virus and Internalization Scale, findings at the Intermolecular and Intermediate Scales will be incorporated at the scale of the viral particles and deformable membranes will be added, with the goal of describing the virus adhesion process, including effects due to membrane bending and tension, using a combination of semi-analytic models and coarse-grained models. The project will thus elucidate quantitatively - for the first time - the biophysical mechanism of EBOV-host cell interaction, providing potential new targets for antiviral drug development. While the focus of the focus of this project is on the EBOV, the approach taken will be applicable to other related virus-host cell interactions.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

病毒引起的疾病，从普通感冒到致命和高度感染性的埃博拉病毒。他们的“作案手法”是通过劫持正常的生理过程，欺骗细胞让它们进入健康细胞，通常像特洛伊木马一样。因此，由于这个原因，针对病毒的疗法设计的主要困难在于尝试试图尝试使用的病毒。阻止他们进入细胞也可能影响正常的生理过程。例如，埃博拉病毒通过从死细胞中掩盖自身作为碎屑（废物或残留）来感染健康细胞。正常功能的健康细胞是清除这种碎屑会错误地吸收埃博拉病毒，因此被感染。但是，病毒和碎屑颗粒之间总是存在一些差异，这表明，如果仔细研究，可能会设计可以阻止特定病毒进入的疗法，同时留下正常的生理过程基本完整。为了在这项尝试中取得成功，有必要在实验和理论上，尤其是后者，以实验性的细节来了解病毒摄取过程，这是该项目的主要目标。基于使用基于显微镜技术来测量分子之间结合力的单独研究的基础，该项目的重点是发展对粘附分子集合的行为的理解（在细胞表面上蛋白会导致细胞与其他细胞或颗粒结合），，并最终为整个病毒颗粒在摄取之前如何附着在细胞上如何附着一个预测模型。这项工作的重要部分是对病毒和细胞颗粒的变形进行建模，以定量测量其性质。如果成功，该项目将有助于建立基于生物学的基于生物学的模型，以便将病毒进入细胞以及病毒和细胞的特性。该研究计划的跨学科性质将为研究生和本科生提供出色的教育和研究机会。研究人员将与Allentown的Da Vinci科学中心合作，设计一个新的展览，展示了病毒摄取的物理和机械细节，以及其研究如何导致潜在的疗法或治疗。（DA Vinci科学中心是一个独立的非营利组织，通过询问来促进动手科学学习，重点介绍每个年轻人都可以在科学方面充满活力和重要的职业机会，并鼓励所有人都好奇和创造力。）该项目的是建立一个通过单病毒水平在分子上的埃博拉病毒（EBOV） - 霍斯特细胞相互作用的实验知情预测和定量模型。尽管已证明EBOV-HOST细胞的附着在细胞表面和病毒外层上的受体之间相互作用的分子生物物理学非常依赖因此，从进入单元格中完全缺乏。最近的工作确定了TIM家族蛋白的重要性以及其粘蛋白样茎结构域（MLD）的几何和机械性能。在这些最新发现的基础上，可以通过使用实验和理论分子生物物理学来实现进一步的进展，以发现对EBOV附着在宿主细胞上的分子，细胞和生物物理机制的定量理解。在单独的研究基础上，利用单分子力光谱来表征Tim家族蛋白如何与EBOV相互作用的实验表征，该项目将开发出生物物理模型，以显示单分子生物力学特性以及MLD的长度，例如其长度的特性如何刚度和电荷密度，控制TIM介导的细胞/病毒膜粘附和吞噬。该模型将分为三个阶段。 1）在分子间尺度上，使用粗粒的布朗动力学模型研究了单个TIM-1和病毒膜之间的粘附，以预测相互作用势。 2）在中间尺度上，将使用与300K布朗尼动力学求解的课程粒度模型一起，将糖蛋白添加到细胞表面，并将糖蛋白添加到病毒表面上，以确定MLD茎的机械性能的作用。 3）在整个病毒和内部化量表的力学上，将在病毒颗粒的尺度上纳入分子间和中间尺度的发现，并将添加可变形的膜，目的是描述病毒粘附过程，包括由于效果膜弯曲和张力，结合了半分析模型和粗粒模型。因此，该项目将首次定量阐明EBOV -HOST细胞相互作用的生物物理机制，从而为抗病毒药药物开发提供了潜在的新靶标。虽然该项目的重点是EBOV，但采用的方法将适用于其他相关病毒宿主相互作用。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子和知识分子优点和评估来支持的更广泛的影响审查标准。