NMR STRUCTURE DETERMINATION OF STEROL CARRIER PROTEIN-2 FROM AEDES AEGYPTI

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 蚊子是一种病媒，在人与人之间传播致病病毒和寄生虫，但蚊子本身不会感染疾病。据估计，在非洲、南美洲、中美洲、墨西哥和亚洲大部分地区，蚊子每年将疾病传播给7000多万人，造成数百万人死亡。在欧洲、俄罗斯、格陵兰岛、加拿大、美国、澳大利亚、新西兰、英国、日本和其他温带和发达国家，蚊子叮咬现在大多是一种令人讨厌的麻烦;但每年仍会造成一些人死亡。 昆虫对胆固醇（细胞膜和蜕皮类固醇生物合成的一种成分）有绝对的饮食需求，而它们本身不能重新合成胆固醇。因此，所有昆虫都必须能够根据需要将胆固醇运输到细胞质中或细胞质周围。 这必须至少包括摄取胆固醇以构建细胞膜、将胆固醇转运至过氧化物酶体以进行分解代谢以及胆固醇在脂肪体中的储存/动员的能力。 因此，胆固醇必须以某种方式在细胞膜和脂滴之间运输，这在昆虫中不像在脊椎动物中那样通过高密度脂质内吞或装载进行。 甾醇载体蛋白-2（SCP-2）是最早在脊椎动物中发现的一种胆固醇载体蛋白。最近，从埃及伊蚊（AeSCP-2）中分离出SCP-2和SCP-X（AeSCP-X）基因。AeSCP-2与大鼠和人类SCP-2具有高度同源性。 具体目的：我们提出了一个生物物理学研究，以阐明结构/功能关系的分子细节，从黄热病蚊子埃及伊蚊（AeSCP-2）和它的靶配体之一：胆固醇的固醇载体蛋白-2。我们将使用NMR光谱来确定apo-AeSCP-2和AeSCP-2的胆固醇结合复合物的结构，并监测配体和抑制剂与AeSCP-2的结合。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Mosquitoes are a vector agent that carries disease-causing viruses and parasites from person to person without catching the disease themselves. Mosquitoes are estimated to transmit disease to more than 70 million people annually in Africa, South America, Central America, Mexico and much of Asia with millions of resulting deaths. In Europe, Russia, Greenland, Canada, the United States, Australia, New Zealand, the UK, Japan and other temperate and developed countries, mosquito bites are now mostly an irritating nuisance; but still cause some deaths each year. Insects have an absolute dietary need for cholesterol (a component of cell membranes and ecdysteroid biosynthesis) which they themselves cannot de novo synthesize. All insects, therefore, must be able to transport cholesterol into and around the cell cytoplasm as needed. This must include at least the ability to uptake cholesterol for the construction of cellular membranes, transport cholesterol to the peroxisome for catabolization and for storage/mobilization of cholesterol in the fat body. Therefore, cholesterol has to be trafficked someway between the cell membrane and the lipid droplet, which has been shown not to be carried out in insects by high-density lipid endocytosis or loading as in the vertebrates. Sterol carrier protein-2 (SCP-2) was first isolated as a cholesterol carrier protein in vertebrates. Recently, the genes for SCP-2 and SCP-X (AeSCP-X) from the yellow fever mosquito, Aedes aegypti (AeSCP-2) were isolated. The AeSCP-2 has a high degree of homology to the rat and human SCP-2. Specific Aims:We propose a biophysical study to elucidate the molecular details in the structure/function relationship of the sterol carrier protein-2 from the yellow fever mosquito Aedes aegypti (AeSCP-2) and one of its target ligand: cholesterol. We will use NMR spectroscopy to determine the structure of apo-AeSCP-2 and cholesterol-bound complex of AeSCP-2 and monitor ligand and inhibitor binding to AeSCP-2.