RED CELL MEMBRANE SKELETON AND MALARIA INFECTION

红细胞膜骨架与疟疾感染

基本信息

批准号：
6301083
负责人：
Mohandas Narla
金额：
$ 21.52万
依托单位：
UNIVERSITY OF CALIF-LAWRENC BERKELEY LAB
依托单位国家：
美国
项目类别：
财政年份：
1999
资助国家：
美国
起止时间：
1999-12-15 至 2000-11-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/6301083
关键词：
Plasmodium falciparum erythrocyte membrane gene targeting genetic library host organism interaction human tissue malaria membrane activity membrane proteins molecular cloning polymerase chain reaction protein protein interaction protozoal antigen tissue /cell culture virulence

项目摘要

The long-term objective of this proposal is to continue to examine the functional consequences of interaction between red cell membrane proteins and proteins elaborated by intraerythrocytic stages of the malarial parasite Plasmodium falciparum. Profound changes occur in the properties of red cell following infection, including markedly reduced deformability and increased adhesiveness. The hypothesis we will explore is that the Parasite-mediated changes in red cell properties are the result of different parasite derived proteins interacting with specific red cell membrane proteins. To accomplish these goals, we propose the following four specific aims: 1) Define the biophysical consequences of interaction between specific malarial proteins and the red cell membrane skeleton. We will determine the effects of these protein-protein interactions on membrane extensional rigidity, membrane viscosity, membrane mechanical integrity and lateral mobility of membrane proteins. The parasite proteins to be studies include the cytoadherence molecule PfEMP-1, and other malaria proteins including HRP-I, MESA, PfEMP-3, and RESA that bind specifically to the red cell membrane skeleton; 2) Define at the molecular level the specific interacting domains of red cell membrane skeletal proteins and P. Falciparum proteins to obtain detailed understanding of how specific protein-protein interactions in infected red cells can induce functional membrane alterations; 3) Define the contribution of various malarial proteins to the strength of adhesion of obtain quantitative insights into the process of cytoadherence. Cytoadherence is a major virulence factor in P. Falciparum infection and involves the specific interaction of the PfEMP-1 protein with receptors on vascular endothelial cells. We will examine whether parasite lines that express antigenic variants of PfEMP-1 bind with differing strengths to the same ligand and also determine whether accessory proteins made by the parasite, such as MESA, HRP-1 and PfEMP-3, modulate the strength of the adhesive interaction; 4) Examine the contributions of specific red membrane proteins to malarial- parasite induced changes in red cell function by comparing the biophysical sequelae that accompany parasite infection of normal red cells with those seen following infection of mutant red cells with either qualitative or quantitative defects in various membrane skeletal proteins. The novel experimental approaches and unique reagents we have developed will be used to carry out these proposed studies. The successful accomplishment of these aims, using molecular engineering in conjunction with novel biophysical approaches, should enable us to further our understanding to the mechanism(s) involved in action of an important human pathogen.

该提案的长期目标是继续审查红细胞膜之间相互作用的功能后果蛋白质和由红细胞内阶段精制的蛋白质疟疾寄生虫恶性疟原虫。深刻的变化发生在感染后红细胞的特性，包括显着降低变形能力和增加的粘附性。我们将假设探索的是寄生虫介导的红细胞特性变化是不同寄生虫衍生的蛋白质相互作用的结果特定的红细胞膜蛋白。为了实现这些目标，我们提出以下四个具体目标： 1）定义生物物理特定疟疾蛋白与疟原虫之间相互作用的后果红细胞膜骨架。我们将确定这些的影响蛋白质-蛋白质相互作用对膜拉伸刚性、膜粘度、膜机械完整性和横向流动性膜蛋白。要研究的寄生虫蛋白包括细胞粘附分子 PfEMP-1 和其他疟疾蛋白，包括与红细胞特异性结合的 HRP-I、MESA、PfEMP-3 和 RESA 膜骨架； 2）在分子水平上定义具体的红细胞膜骨骼蛋白和 P 的相互作用域。详细了解恶性疟原虫蛋白的特异性受感染红细胞中的蛋白质-蛋白质相互作用可以诱导功能性红细胞膜改变； 3) 定义各种疟疾的贡献蛋白质的粘附强度获得定量见解进入细胞粘附过程。细胞粘附是主要毒力恶性疟原虫感染的因素并涉及特定的相互作用 PfEMP-1 蛋白与血管内皮细胞上的受体的结合。我们将检查是否表达抗原变体的寄生虫系 PfEMP-1 以不同的强度与同一配体结合，并且确定寄生虫是否产生辅助蛋白，例如 MESA， HRP-1 和 PfEMP-3，调节粘合相互作用的强度； 4）检查特定红膜蛋白对疟疾的贡献通过比较寄生虫诱导红细胞功能的变化正常红寄生虫感染伴随的生物物理后遗症突变红细胞感染后观察到的细胞各种膜骨架的定性或定量缺陷蛋白质。我们拥有新颖的实验方法和独特的试剂开发的将用于开展这些拟议的研究。这利用分子工程成功实现了这些目标与新颖的生物物理方法相结合，应该使我们能够进一步加深我们对参与行动的机制的理解重要的人类病原体。