New genes affecting the SREBP pathway in mammalian and drosophila cells

影响哺乳动物和果蝇细胞中 SREBP 通路的新基因

• 批准号: 6910657
• 负责人: JOSEPH L GOLDSTEIN
• 金额: $ 32.1万
• 依托单位: UT SOUTHWESTERN MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-07-01 至 2007-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6910657
• 关键词: CHO cells; DNA binding protein; Drosophilidae; auxotrophy; blood lipoprotein metabolism; chemical cleavage; cholesterol; endopeptidases; fatty acid metabolism; gene mutation; genetic mapping; genetic regulation; genetic screening; intracellular transport; lipid transport; low density lipoprotein receptor; microarray technology; mutant; protein structure function; proteolysis; steroid metabolism; transcription factor

DESCRIPTION: (provided by applicant) During the past four years, we have used mutant mammalian cells to clone three new genes essential to the SREBP pathway that regulate cholesterol and fatty acid metabolism in mammalian cells. These three genes are SREBP cleavage-activating protein (SCAP), Site-1 protease (S1P), and Site-2 protease (S2P). The mutant cells have also proven crucial to our analysis of the function of these loci. We will continue to use the tools of mammalian cell genetics to pursue the hypothesis that additional essential genes regulating the SREBP signaling pathway remain to be discovered. In particular, we seek to identify the gene encoding a putative "ER retention protein" that is required for the sterol-regulated movement of the SCAP/SREBP complex between the endoplasmic reticulum (ER) and the Golgi. This protein may hold the key to the cholesterol feedback phenomenon. In addition, we will initiate a new direction, in Drosophila, to extend our genetic analysis of the SREBP pathway to an organism that cannot synthesize cholesterol. In cultured Drosophila cells, our aim is to identify metabolites that regulate SREBP activity in flies, as well as to identify the gene targets of this pathway. The lack of cholesterol synthesis in flies will allow us to study the regulation of SREBP signaling by non-sterol metabolites in the absence of the complications of the sterol-mediated regulation observed in mammalian systems. We will study the SREBP pathway in vivo by creating mutant flies lacking SREBP, S1P, S2P, and SCAP. These mutants will enable us to identify and characterize phenotypes associated with the loss of function of the SREBP pathway in an animal in which cholesterol feedback is not a normal control mechanism. Once such phenotypes are known, we will use genetic strategies unique to Drosophila to screen for genes involved in the SREBP pathway that would otherwise be difficult to identify in the mammalian system.

描述：（申请人提供） 在过去的四年中，我们使用突变哺乳动物细胞克隆 调节胆固醇的SREBP途径必不可少的三个新基因 哺乳动物细胞中的脂肪酸代谢。这些 三个基因是SREBP切割激活蛋白（SCAP），Site-1蛋白酶 （S1P）和Site-2蛋白酶（S2P）。突变细胞也已证明至关重要 我们分析这些基因座的功能。我们将继续使用 哺乳动物细胞遗传学的工具，以提出额外的假设 调节SREBP信号通路的必需基因仍然是 发现。特别是，我们试图确定编码推定的基因 固醇调节运动所需的“ ER保留蛋白” 内质网（ER）和高尔基体之间的SCAP/SREBP复合物。 该蛋白可能是胆固醇反馈现象的关键。 此外，我们将在果蝇中启动一个新的方向，以扩展我们的 无法合成的生物的SREBP途径的遗传分析 胆固醇。在培养的果蝇细胞中，我们的目的是鉴定代谢物 调节果蝇中的SREBP活性，并确定基因靶标 这条路。缺乏苍蝇中胆固醇的合成将使我们能够 研究非肉酚代谢物对SREBP信号的调节 没有观察到的固醇介导的调节的并发症 哺乳动物系统。我们将通过创建突变体在体内研究SREBP途径 缺乏SREBP，S1P，S2P和SCAP的苍蝇。这些突变体将使我们能够 识别和表征与功能丧失相关的表型 胆固醇反馈不是正常的动物中的SREBP途径 控制机制。一旦知道了这种表型，我们将使用遗传 果蝇独有的策略以筛选涉及SREBP的基因 否则在哺乳动物系统中很难识别的途径。