Interaction of the Estrogen Receptor with DNA

描述（由申请人提供）：类固醇激素雌激素在女性生殖和乳腺组织的发育和维持中起关键作用，但也参与心血管、骨骼和神经细胞功能。 雌激素和选择性雌激素受体调节剂广泛用于调节生育能力、缓解绝经后症状、预防和治疗乳腺癌。这些激素的生物学效应是通过与雌激素受体（ER）结合并诱导受体与靶基因中的雌激素反应元件（ERE）结合而启动的。正是这种受体与ERE的相互作用，与多种共调节蛋白合作，导致基因表达的变化。在上一个奖项期间，我们分离并鉴定了100多种与DNA结合的ER α相关的蛋白质，并表明这些ER α相关蛋白质中的一些与受体相互作用，增加受体与DNA的相互作用，并影响受体介导的基因表达。有趣的是，这些蛋白质不是单独发挥作用，而是形成具有各种酶和催化功能的集成网络。我们发现的一些蛋白质参与对氧化应激的反应，氧化应激与衰老和人类疾病有关。氧化应激蛋白在维持正常细胞功能中起关键作用。使用分子、细胞和体内方法，我们将（1）确定雌激素是否增加C57 BL/6小鼠大脑皮层中氧化应激蛋白Cu/Zn超氧化物歧化酶（SOD 1）、硫氧还蛋白（Trx）、硫氧还蛋白还原酶（TrxR）、蛋白质二硫键异构酶（PDI）和脱嘌呤核酸内切酶1（APE 1）的表达，（2）使用器官型脑切片培养物确定雌激素和/或孕激素是否改变大脑皮层中氧化应激蛋白的表达，（3）描述激素是否-氧化应激蛋白的诱导表达在保护大脑皮层免受局部缺血中起作用并鉴定参与这种神经保护的各个氧化应激蛋白，和（4）确定氧化应激蛋白在雌激素应答基因表达中的作用。 所获得的见解将有助于描述雌激素和其他激素配体如何调节大脑中的基因表达，增强我们对大脑对一系列临床重要药物的细胞反应性的理解，并定义可能有助于保护大脑免受缺血性损伤（如中风）的激素治疗。

DESCRIPTION (provided by applicant): The steroid hormone estrogen plays a critical role in the development and maintenance of female reproductive and mammary tissues, but is also involved in cardiovascular, skeletal, and neural cell function. Estrogens and selective estrogen receptor modulators are widely used in regulating fertility, alleviating postmenopausal symptoms, and preventing and treating breast cancer. The biological effects of these hormones are initiated by binding to the estrogen receptor (ER) and inducing the receptor to bind to estrogen response elements (EREs) residing in target genes. It is this interaction of the receptor with the ERE, in cooperation with multiple coregulatory proteins, that leads to changes in gene expression. During the previous award period, we isolated and identified more than 100 proteins that associate with the DNA-bound ERa and showed that a number of these ERa-associated proteins interact with the receptor, increase the interaction of the receptor with DNA, and influence receptor-mediated gene expression. Interestingly, rather than functioning individually, these proteins form integrated networks endowed with a variety of enzymatic and catalytic functions. A number of the proteins we identified are involved in responding to oxidative stress, which has been linked to aging and human disease. Oxidative stress proteins play pivotal roles in maintaining normal cell function. Using molecular, cell-based, and in vivo approaches we will (1) determine whether estrogen increases expression of the oxidative stress proteins Cu/Zn superoxide dismutase (SOD1), thioredoxin (Trx), thioredoxin reductase (TrxR), protein disulfide isomerase (PDI), and apurinic endonuclease 1 (APE1) in the cerebral cortex of C57BL/6 mice, (2) define whether estrogens and/or progestins alter the expression of oxidative stress proteins in the cerebral cortex using organotypic brain slice cultures, (3) delineate whether hormone-induced expression of oxidative stress proteins plays a role in protecting the cerebral cortex from ischemia and identify the individual oxidative stress proteins involved in this neuroprotection, and (4) define the role of oxidative stress proteins in estrogen-responsive gene expression. The insights gained will help delineate how estrogens and other hormonal ligands regulate gene expression in the brain, enhance our understanding of the cellular responsiveness of the brain to an array of clinically important pharmaceutical agents, and define hormonal treatments that may help to protect the brain from ischemic insults such as stroke.