INTERACTIONS OF APO A-I WITH LIPIDS AND CELL SURFACES

这个项目的目标是阐明分子机制 载脂蛋白（apo）A-I功能的基础， 胆固醇转运（RCT）。载脂蛋白A-I是高脂血症的主要蛋白质， 高密度脂蛋白（HDL），这种分子的功能是 这种脂蛋白的抗动脉粥样硬化特性。具体目标1是 确定apo A-I的结构域，这些结构域对于磷脂结合至关重要 (PL)以及各种HDL颗粒的组装;这是 重要的是，apo A-I参与RCT的方式取决于 在其脂化状态下。载脂蛋白的结构与功能关系 将使用通过诱变改变的蛋白质分子来检查A-I。 具体目标2是定义“膜”中涉及的分子事件 微增溶”过程，通过该过程， 从细胞质膜上除去未酯化的胆固醇和磷脂。 具体目标3是阐明载脂蛋白A-I作为配体的行为， 清道夫受体（SR）-B1受体及其作用的分子机制 通过结合介导的胆固醇酯的选择性摄取进入细胞 高密度脂蛋白与这个受体结合。血浆载脂蛋白A-I的脂质结合能力， 工程化的apoA-I和模型肽将使用一系列的 物理生化技术。载脂蛋白A-I的功能结构域 参与介导胆固醇和脂质在细胞表面的转运 将通过在细胞中使用各种工程化的apo A-I分子来定义 文化体系。该项目的成果将提供更大的 了解HDL保护早产儿的机制 冠心病

The goal of this project is to elucidate the molecular mechanisms underlying the functions of apolipoprotein (apo) A-I in reverse cholesterol transport (RCT). Apo A-I is the major protein of plasma high density lipoprotein (HDL) and the functions of this molecule underlie the anti-atherogenic properties of this lipoprotein. Specific Aim 1 is to define the domains of apo A-I critical for the binding of phospholipid (PL) and the assembly of various types of HDL particles; this is significant because the ways in which apo A-I participates in RCT depend upon its state of lipidation. The structure-function relationships of apo A-I will be examined using protein molecules altered by mutagenesis. Specific Aim 2 is to define the molecular events involved in the "membrane micro-solubilization" process by which lipid-poor apo A-I (pre-beta-HDL) removes unesterified cholesterol and PL from the plasma membrane of cells. Specific Aim 3 is to elucidate the behavior of apo A-I as a ligand for the scavenger-receptor (SR)-B1 receptor and the molecular mechanism of the selective uptake into cells of cholesteryl ester mediated by the binding of HDL to this receptor. The lipid-binding capabilities of plasma apo A-I, engineered apo A-I and model peptides will be determined using a range of physical-biochemical techniques. The functional domains of apo A-I involved in mediating cholesterol and lipid transport at cell surfaces will be defined by using various engineered apo A-I molecules in cell culture systems. The results of this project will provide greater understanding of the mechanisms by which HDL protects against premature coronary artery disease.