CHOLESTEROL-PROTEIN INTERACTIONS IN BLOOD

本应用程序的目的是研究 胆固醇和蛋白质在人体红细胞膜和其他 哺乳动物膜系统，以及在人血清脂蛋白中， 高密度脂蛋白（HDL）。 这 调查预计将提供新的想法有关的作用， 胆固醇在动脉粥样硬化和正常哺乳动物中的发病机制 细胞生长 具体来说，胆固醇-蛋白质相互作用可以调节 质膜Na+K+ ATP酶的活性，从而生化 将人类肥胖、高血清胆固醇水平和动脉粥样硬化联系起来; 胆固醇-蛋白质相互作用在人LDL中可能不同于在 人HDL，这可能与这两种脂蛋白的相反作用有关 在动脉粥样硬化发病机制中的作用;胆固醇蛋白 相互作用可以为优先定位提供生物化学基础 胆固醇在哺乳动物细胞的质膜。 将在人体红细胞中研究胆固醇-蛋白质相互作用 膜和比较，与Na+K+ ATP酶的相互作用将是 研究了红细胞膜和重组酶， 肾髓质 胆固醇-蛋白质相互作用也将在 LDL和HDL。 除了基础生物化学， 准备和表征这些系统，六种方法来研究 胆固醇-蛋白质相互作用将被采用，除了一个新的 适用于这个问题。 31 P核磁共振（NMR） 将使用磷脂和13 C标记胆固醇的13 C NMR，如 将圆二色性（CD）和荧光的衍生物 胆固醇，圆二色性和帕里那酸荧光，脂质探针，相位 磷脂的转变行为和ATP酶的酶活性。 这一多方面的办法预计将提供一个相当完整的情况 胆固醇的行为相对于蛋白质，在一个领域， 以前有过资料。

The purpose of this application is to investigate interactions between cholesterol and proteins in the human erythrocyte membrane and other mammalian membrane systems, and in the human serum lipoproteins, low density kipoprotein (LDL) and high density lipoprotein (HDL). This investigation is anticipated to provide new ideas concerning the role of cholesterol in the pathogenesis of atherosclerosis and in normal mammalian cell growth. Specifically, cholesterol-protein interactions may modulate the activity of the plasma membrane Na+K+ATPase, thereby biochemically linking human obesity, high serum cholesterol levels and atherosclerosis; cholesterol-protein interactions are likely different in human LDL than in human HDL, which may relate to the opposite roles these two lipoproteins play in the pathogenesis of atherosclerosis; cholesterol-protein interactions may provide a biochemical basis for the preferential location of cholesterol in the plasma membrane of mammalian cells. Cholesterol-protein interactions will be studied in the human erythrocyte membrane and for comparison, interactions with the Na+K+ATPase will be studied in the erythrocyte membranes and in recombinants of enzyme from kidney medulla. Cholesteral-protein interactions will also be studied in LDL and HDL. In addtiion to the basic biochemistry devoted to carefully preparing and characterizing these systems, six approaches to studying cholesterol-protein interactions will be employed, all but one of them new in application to this question. 31P nuclear magnetic resonance (NMR) of the phospholipids and 13C NMR of 13C labelled cholesterol will be used, as will circular dichroism (CD) and fluorescence of a derivative of cholesterol, CD and fluorescence of parinaric acid, a lipid probe, phase transition behavior of phospholipids, and enzyme activity of the ATPases. This multifaceted approach is expected to provide a rather complete picture of cholesterol behavior with respect to protein, in a field where almost no information was available previously.