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：（由申请人提供） 在过去的四年里，我们利用突变的哺乳动物细胞来克隆 调节胆固醇的 SREBP 通路所必需的三个新基因 和哺乳动物细胞中的脂肪酸代谢。这些 三个基因是 SREBP 裂解激活蛋白 (SCAP)、Site-1 蛋白酶 (S1P) 和位点 2 蛋白酶 (S2P)。突变细胞也被证明至关重要 以便我们分析这些位点的功能。我们将继续使用 哺乳动物细胞遗传学工具来追求额外的假设 调节 SREBP 信号通路的重要基因仍有待研​​究 发现了。特别是，我们寻求鉴定编码假定的基因 甾醇调节运动所需的“ER 保留蛋白” 内质网 (ER) 和高尔基体之间的 SCAP/SREBP 复合体。 这种蛋白质可能是胆固醇反馈现象的关键。 此外，我们将在果蝇领域启动一个新方向，以扩展我们的研究范围。 对无法合成的生物体的 SREBP 途径进行遗传分析 胆固醇。在培养的果蝇细胞中，我们的目标是鉴定代谢物 调节果蝇中的 SREBP 活性，以及​​识别基因靶点 这条途径的。果蝇缺乏胆固醇合成将使我们能够 研究非甾醇代谢物对 SREBP 信号的调节 没有观察到的甾醇介导调节的并发症 哺乳动物系统。我们将通过创建突变体来研究体内 SREBP 通路 果蝇缺乏 SREBP、S1P、S2P 和 SCAP。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 胆固醇反馈不正常的动物中的 SREBP 通路 控制机制。一旦了解了这些表型，我们将使用遗传 果蝇独有的筛选 SREBP 相关基因的策略 否则在哺乳动物系统中很难识别的途径。