SIGNALING BY NON-CLASSICAL LIGANDS OF ESTROGEN RECEPTOR NOVEL APPROACHES TO DET

雌激素受体非经典配体的信号传导检测新方法

• 批准号: 7381384
• 负责人: BARRY D GEHM
• 金额: $ 9.74万
• 依托单位: UNIV OF ARKANSAS FOR MED SCIS
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-05-01 至 2007-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7381384
• 关键词: SIGNALING; NON; CLASSICAL; LIGANDS; ESTROGEN

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. Estrogens affect a large number of physiological functions and disease states. In addition to endogenous hormones, humans are exposed to a wide variety of estrogenic compounds in the diet, environment, and pharmaceuticals. These non-classical ligands for the estrogen receptor (ER) can have major effects on human health. Aim 1: Efficient methods of testing for estrogenic activity are important for drug development, environmental testing, and research on receptor functions and mechanisms. Yeast-based assays using exogenously expressed ERs and reporter genes are inexpensive and widely used, but have the defect that the response to some SERMS (selective estrogen receptor modulators) and phytoestrogens is very different from that seen in mammalian cells. This project will develop and test a reporter system in the nematode C. elegans, which is easily grown in culture. It is hypothesized that the closer evolutionary relationship of humans and C. elegans will enable this system to produce more relevant results than yeast-based assays, but retain the advantages of simplicity and low cost. Aim 2: Although there is substantial human exposure to non-classical ER ligands, their modes of action are incompletely understood. SERMs such as tamoxifen often have biphasic dose-response curves, with ER agonism at low concentrations and antagonism at high concentrations. It has been proposed that in addition to occupying the hormone-binding pocket of ER, these compounds bind (with lower affinity) to a 2nd site that mediates antagonism. Some phytoestrogens have a similar biphasic effect, suggesting that they are natural ligands for this site. This project will determine if phytoestrogens and ANGELS (activators of non-genotropic estrogen-like signaling, a new class of ER-targeted drugs) compete with SERMS for binding to the 2nd site, identify and ablate the site via targeted mutagenesis, and characterize the significance of the site in ER function by reporter gene assays, microarray analysis and real-time PCR.

该子项目是利用 NIH/NCRR 资助的中心拨款提供的资源的众多研究子项目之一。子项目和研究者 (PI) 可能已从另一个 NIH 来源获得主要资金，因此可以在其他 CRISP 条目中得到体现。列出的机构是中心的机构，不一定是研究者的机构。雌激素影响大量的生理功能和疾病状态。除了内源性激素外，人类还接触饮食、环境和药物中的多种雌激素化合物。这些雌激素受体 (ER) 的非经典配体可以对人类健康产生重大影响。目标 1：有效的雌激素活性测试方法对于药物开发、环境测试以及受体功能和机制研究非常重要。使用外源表达的 ER 和报告基因的基于酵母的测定价格低廉且广泛使用，但其缺陷是对某些 SERMS（选择性雌激素受体调节剂）和植物雌激素的反应与哺乳动物细胞中观察到的反应非常不同。该项目将开发和测试线虫秀丽隐杆线虫的报告系统，该线虫很容易在培养物中生长。据推测，人类和线虫之间更密切的进化关系将使该系统能够产生比基于酵母的测定更相关的结果，但保留简单和低成本的优势。目标 2：尽管人类大量接触非经典 ER 配体，但它们的作用方式尚不完全清楚。 SERM（例如他莫昔芬）通常具有双相剂量反应曲线，低浓度时具有 ER 激动作用，高浓度时具有拮抗作用。有人提出，除了占据 ER 的激素结合袋外，这些化合物还与介导拮抗作用的第二个位点结合（以较低的亲和力）。一些植物雌激素具有类似的双相效应，表明它们是该位点的天然配体。该项目将确定植物雌激素和 ANGELS（非遗传性雌激素样信号传导激活剂，一类新型 ER 靶向药物）是否与 SERMS 竞争与第二个位点的结合，通过靶向诱变识别和消除该位点，并通过报告基因测定、微阵列分析和实时 PCR 表征该位点在 ER 功能中的重要性。