STEROL CARRIER PROTEIN-2 GENE EXPRESSION

甾醇载体蛋白-2 基因表达

• 批准号: 2133839
• 负责人: CHARLES L BAUM
• 金额: $ 8.88万
• 依托单位: UNIVERSITY OF CHICAGO
• 依托单位国家: 美国
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-07-01 至 1997-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2133839
• 关键词: antisense nucleic acid; cell growth regulation; cell membrane; cholesterol; gene expression; laboratory rat; liver metabolism; phosphorylation; protein biosynthesis; steroid biosynthesis; sterols; tissue /cell culture; transfection; transport proteins

The Principal Investigator's long term research objectives are to elucidate the role of sterol carrier protein-2 (SCP2) in hepatocellular trafficking and maintenance of cellular unesterified cholesterol levels. Ultimately, this information will be applicable to the study of a variety of disease states associated with derangements in these processes, particularly atherosclerosis. Current knowledge of cellular cholesterol metabolism suggests that SCP2, a well characterized in vitro cholesterol transfer protein, may be important in mediating the intermembrane and intramembrane transfer of cholesterol. This has important implications for the regulation of both cholesterol synthesis and metabolism. At present little is known about the in vivo function of this protein, however, the limited data available suggests a complex pattern of tissue specific expression and regulation which suggests that SCP2 may have different functions depending on the cell type examined. In the liver, SCP2 is a highly expressed peroxisomal protein which is regulated in association with growth specific cues. We postulate that SCP2 may function as a substrate dependant cofactor in cholesterol and bile acid synthesis and in new membrane formation during periods of cell growth. The specific aims of this study are: (1). To elucidate the mechanisms involved in the regulation of cellular levels of SCP2; (2). To inhibit SCP2 expression using antisense oligonucleotides and to correlate this with changes in cholesterol synthesis and plasma membrane cholesterol levels in growth stimulated cells; and (3). To overexpress SCP2 using an eukaryotic expression vector-SCP2 cDNA construct and measure the influence of this change on cholesterol metabolism. For these studies we will utilize Reuber H-35 rat hepatoma cells which are well differentiated and retain many of the synthetic functions of normal rat liver, prominent among which is the synthesis of bile acids. Modulation of SCP2 levels by growth factors and peroxisomal proliferators will be examined to determine the translational and post-translational processes involved in the regulation of SCP2 levels. The role of SCP2 in hepatocellular cholesterol and bile acid synthesis and in new membrane formation will be assessed by correlating changes in these events with alterations in the level of SCP2 expression. Successful completion of these studies will provide important insights into the role of this protein in cellular cholesterol metabolism.

主要研究者的长期研究目标是 阐明固醇载体蛋白-2（SCP2）在肝细胞中的作用 贩运和维持细胞未酯化的胆固醇水平。 最终，此信息将适用于多种多样的研究 在这些过程中与危险有关的疾病状态 特别是动脉粥样硬化。 当前对细胞胆固醇代谢的了解表明SCP2， 体外胆固醇转移蛋白的表征良好，可能是 对于介导膜间和膜内转移至关重要 胆固醇。 这对两者的调节都有重要意义 胆固醇的合成和代谢。 目前对 但是，该蛋白质的体内功能，可用的有限数据 提出了组织特异性表达和调节的复杂模式 这表明SCP2可能具有不同的功能 检查了细胞类型。 在肝脏中，SCP2是高度表达的过氧化物组 与生长特定线索相关的蛋白质。 我们 假设SCP2可能充当底物依赖辅因子 胆固醇和胆汁酸合成以及在新的膜形成中 细胞生长时期。 这项研究的具体目的是：（1）。 阐明机制 参与SCP2细胞水平的调节； （2）。 抑制 使用反义寡核苷酸的SCP2表达并将其关联 随着胆固醇合成和质膜胆固醇的变化 生长刺激细胞的水平； （3）。 使用一个过表达SCP2 真核表达载体-SCP2 cDNA构建并测量 这种变化对胆固醇代谢的影响。 对于这些研究，我们 将利用雷伯H-35大鼠肝癌细胞的分化有很好的分化 并保留正常大鼠肝的许多合成功能 其中是胆汁酸的合成。 通过 将检查生长因子和过氧化物酶体增生剂 确定涉及的翻译和后翻译过程 SCP2水平的调节。 SCP2在肝细胞中的作用 胆固醇和胆汁酸合成以及在新的膜形成中将是 通过将这些事件的变化与改变的变化进行评估 SCP2表达水平。 这些研究的成功完成将 提供有关该蛋白在细胞中作用的重要见解 胆固醇代谢。