Membrane Control of Protein-Protein Contact. Simulation Based on Phase Diagrams

描述（由申请人提供）：病毒侵入所有形式的生命，导致人类疾病，包括艾滋病毒-艾滋病。 尽管病毒种类繁多，但所有包膜病毒，包括HIV-1和劳斯肉瘤病毒（RSV），都必须与质膜的内小叶结合。 我们的实验室已经进行了大规模的努力，以表征膜组件之间的相互作用。 目的是发现哪些膜因子控制膜相关病毒基质蛋白之间的相互作用。 整体的方法是结合联合收割机实验测量，主要是FRET和荧光显微镜，Monte Carlo计算机模拟，以发现所有的重要的相互作用能量之间的脂质，脂质蛋白质，蛋白质蛋白质。 首先在模型脂质体中测量膜相行为和蛋白质-蛋白质相互作用，然后在活鸡成纤维细胞中测量。 第一个具体目标是开发实验和蒙特卡罗模拟来描述短杆菌肽-短杆菌肽在含有胆固醇的简单3-脂质组分混合物中的相互作用。 第二个目标是处理第五种成分神经酰胺或甘油二酯的复杂性大大增加。 该目标包括提出开发“脂质缓冲剂”，以控制模型或真实的生物膜中胆固醇、神经酰胺或甘油二酯的化学势。 第三个目的是表征HIV-1和RSV基质蛋白-蛋白在脂质混合物中的相互作用，该脂质混合物模拟动物细胞质膜的内小叶，作为理解活细胞中行为的基础。 第四个也是最后一个目的是在活细胞中使用FRET检查质膜内小叶处的HIV-1和RSV基质蛋白-蛋白相互作用，试图找到控制相互作用的因素，以及是否观察到与外小叶的偶联。对病毒性疾病，特别是艾滋病毒-艾滋病的有效治疗并不限于“全部治愈或全部不治愈”。 药物组合，每一种都减缓了病毒生命周期的一个步骤，已经被证明是有用的。 拟议的研究将导致详细了解膜组分胆固醇，神经酰胺和甘油二酯，所有这些都可以通过药物部分调节，控制病毒生命中的一个关键步骤-质膜上的缔合/组装。

DESCRIPTION (provided by applicant): Viruses invade all forms of life, causing diseases in humans including HIV-AIDS. Although the variety of viruses is daunting, all enveloped viruses, including HIV-1 and Rous Sarcoma Virus (RSV), must associate with the inner leaflet of plasma membranes. Our laboratories have undertaken a large-scale effort to characterize interactions between membrane components. The goal is to discover which membrane factors exert control over the interactions between membrane-associated viral matrix proteins. The overall approach is to combine experimental measurements, mainly FRET and fluorescence microscopy, with Monte Carlo computer simulations in order to discover all of the significant interaction energies between lipid-lipid, lipid-protein, and protein-protein. Membrane phase behavior and protein-protein interactions are first measured in model liposomes and then in live chicken fibroblast cells. The first specific aim is to develop the experiments and Monte Carlo simulations to describe gramicidin-gramicidin interactions in a simple 3-lipid component mixture containing cholesterol. The second aim is to handle the greatly increased complexity of a fifth component, ceramide or diacylglycerol. This aim includes proposed development of a "lipid buffer" in order to control the chemical potential of cholesterol, ceramide, or diacylglycerol in model or real biomembranes. The third aim is to characterize HIV-1 and RSV matrix protein-protein interactions in a lipid mixture that models the inner leaflet of an animal cell plasma membrane, as a basis for understanding behavior in live cells. The fourth and final aim is to examine HIV-1 and RSV matrix protein-protein interactions at the inner leaflet of the plasma membrane using FRET in live cells, attempting to find the factors that control the interactions, and whether coupling to the outer leaflet is observed. Useful treatments for viral afflictions, in particular HIV-AIDS, are not limited to "all or none" cures. Combinations of drugs, each of which slows down a step of the viral life cycle, have proven useful. The proposed research will lead to detailed understanding of how the membrane components cholesterol, ceramide, and diacylglycerol, all of which can be partially regulated by drugs, control one critical step in the life of the virus - association/assembly at the plasma membrane.