Regulation of Endothelial Cells by the OX-Papc Network

我们的研究表明，磷脂氧化产物（Ox-PAPC），积累在 动脉粥样硬化病变是内皮细胞功能的重要调节因子，影响过表达的mRNA水平。 1000个基因涉及炎症、固醇调节、凝血、氧化应激、细胞周期、血管生成， 氧化还原调节和未折叠蛋白质反应。Ox-PAPC的炎症反应及其对细胞增殖的影响 组成脂质PEIPC显示出与IPS和TNF的那些显著不同，导致慢性炎症。 单核细胞-内皮细胞相互作用的上调。拟议研究的一个主要目标是确定 Ox-PAPC/PEIPC网络的关键调节因子。在Aim中 1我们将使用细胞生物学方法来测试由Ox激活的基本信号传导机制的三个方面， PAPC和PEIPC。我们将：定义Ox-PAPC受体复合物的其他成分;确定如何 Ox-PAPC和PEIPC改变细胞氧化还原平衡以控制基因表达;并确定是否 PEIPC与蛋白质的共价结合在活化中是重要的。在目标2中，我们将使用整合遗传学 一种在转录水平上定义整体网络的方法，利用共同遗传学的概念， 群体中的变化可用于将表达阵列数据组织成生物学相关模块。 我们将使用全基因组关联来绘制网络中导致常见变异的基因， 将数据与正交蛋白质组学和功能数据集整合。目标1和2还将包括 通过使用siRNA和在某些情况下过表达来验证重要的调节子。在目标3中， 确定内皮细胞是否表达三种重要的网络调节因子（SREBP，STAT 3和HO-1） 在小鼠动脉粥样硬化中起重要作用。对于这些研究，我们将采用LDL受体敲除小鼠 内皮特异性敲除这些蛋白质。此外，人类病变的炎症区域将被 检测这些分子的表达和激活，以及我们发现的调节网络的其他分子。 总之，这些研究将确定控制动脉粥样硬化的潜在内皮靶点。

Our studies have demonstrated that phospholipid oxidation products (Ox-PAPC) which accumulate in atherosclerotic lesions are important regulators of endothelial cell function, affecting mRNA levels of over 1000 genes involving inflammation, sterol regulation, coagulation, oxidative stress, cell cycle, angiogenesis, redox regulation and the unfolded protein response. The inflammatory response to Ox-PAPC and to its component lipid PEIPC was shown to differ significantly from those of IPS and TNF, leading to a chronic upregulation of monocyte-endothelial interactions. A major goal of the proposed studies is to identify the pivotal regulators of the Ox-PAPC/PEIPC network using cell biology and bioinformatics approaches. In Aim 1 we will use a cell biology approach to test three aspects of the basic signaling mechanism activated by Ox- PAPC and PEIPC. We will: define additional components of the Ox-PAPC receptor complex; determine how Ox-PAPC and PEIPC alter the cellular redox balance to contol gene expression; and determine whether covalent binding of PEIPC to proteins is important in activation. In Aim 2, we will use an integrative genetics approach to define the overall network at the transcript level, leveraging the concept that common genetic variations in the population can be used to organize expression array data into biologically relevant modules. We will map the genes contributing to common variation in the network using genome-wide association and integrate the data with orthogonal proteomic and functional datasets. Aims 1 and 2 will also include validation of important regulators by use of siRNA and in some cases overexpression. In Aim 3 we will determine whether endothelial expression of three important network regulators (SREBP, STAT3 and HO-1) plays an important role in atherosclerosis in mice. For these studies, we will employ LDL receptor null mice with endothelial specific knockout of these proteins. In addition, inflammatory areas of human lesions will be examined for expression and activation of these molecules and others we find to regulate the network. Together, these studies will identify potential endothelial targets for the control of atherosclerosis.