REGULATABLE GENE TRANSFER SYSTEM

人低密度脂蛋白受体主要在肝脏表达，其功能是 清除循环中的低密度脂蛋白和胆固醇。低密度脂蛋白的突变 受体已被证明会导致高胆固醇血症，这通常会导致 在早期的心血管疾病和心肌梗死中。这个 该项目的目标是使用诱导式系统来明确目标 转基因小鼠肝脏人低密度脂蛋白受体的研究 用腺病毒载体传递该诱导系统的效果 进入细胞培养。诱导系统由嵌合体组成 转录调节因子GLVP和含有该结合的靶基因 监管机构认可的网站。在诱导剂RU486存在的情况下， 该调节因子结合并激活靶基因的表达。这是可以诱导的 此前已经证明，该系统可以有效地诱导 多种靶基因在细胞培养和转基因小鼠中的表达 到5000倍。为了研究人类低密度脂蛋白受体的受控表达， 我们建议：1)。生成包含该基因的转基因小鼠靶线 人低密度脂蛋白受体-c DNA；产生双转基因小鼠系，能够 外源配体诱导表达人低密度脂蛋白受体； 通过将病毒激活结构域替换为 来自人类转录因子的激活结构域，以促进 4)该诱导系统在基因治疗中的应用前景； 低密度脂蛋白受体在培养细胞中的诱导表达 腺病毒递送系统。这些研究对于为我们提供 血清低密度脂蛋白受体表达和清除的重要动力学数据 低密度脂蛋白和胆固醇。我们期待这次调查的结果 将使我们能够为未来的人类基因制定更好的方案 高胆固醇血症等心血管疾病的治疗研究。

Human LDL receptor is expressed primarily in the liver and functions to clear the LDL and cholesterol from the circulation. Mutations of the LDL receptor have been shown to cause hypercholesterolemia which often results in cardiovascular diseases and myocardial infarction at an early age. The goal of this project is to use an inducible system to specifically target the human LDL receptor to the liver in transgenic mice as well as to study the efficacy of using adenoviral vector to deliver this inducible system into cell culture. The inducible system consists of a chimeric transcriptional regulator GLVP and a target gene containing the binding sites recognized by the regulator. In the presence of an inducer, RU486, the regulator binds and activates target gene expression. This inducible system has previously been demonstrated to effectively induce the expression of various target genes in cell culture and transgenic mice up to 5000-fold. To investigate controlled expression of human LDL receptor, we propose to: 1). Generate transgenic mouse target lines containing the human LDL receptor- cDNA; 2). Generate bitransgenic mouse lines capable of expressing the human LDL receptor in response to exogenous ligand; 3). Modify the regulator by substituting the viral activation domain with an activation domain from a human transcription factor to facilitate the future application of this inducible system for gene therapy; 4). Inducible expression of the LDL receptor in cultured cells using adenoviral delivery system. These studies are crucial in providing us with important kinetic data on LDL receptor expression and clearance of serum LDL and cholesterol. We expect that the results from this investigation shall enable us to formulate better protocols for future human gene therapy study in hypercholesterolemia and other cardiovascular diseases.