Interaction of the Estrogen Receptor with DNA

类固醇激素雌激素在女性的发育和维持中起着关键作用 生殖和乳腺组织，但也参与维持心血管，骨骼和神经系统， 功能、乳腺癌细胞的增殖和男性生殖道中精子的浓度。 此外，雌激素和抗雌激素被广泛用于调节生育，缓解绝经后 症状，预防和治疗乳腺癌。雌激素的生物学效应是通过结合 与细胞内雌激素受体（ER）结合，并诱导ER与雌激素反应元件（ERE）结合， 存在于靶基因中。正是ER与ERE的这种相互作用，与多个协同调节因子合作， 蛋白质，导致基因表达的变化。在上一个奖项期间，我们证明了， 单个ERE引起ER构象的不同变化，这些ERE诱导的受体变化 构象影响辅激活因子的募集并最终改变基因表达。因此，DNA就像一个 激素配体作为受体构象的变构调节剂发挥作用。长期目标是 该提案旨在阐明参与调节雌激素反应基因的机制。我们建议隔离 并鉴定在不同内质网和激素存在下与内质网相关的蛋白质， 这些蛋白质通过不同的ERE对受体结合和激活转录的能力的影响 序列，并阐明这些蛋白质影响ER介导的反式激活的机制， 分子和生物化学分析。我们将测试我们在体外观察的生理相关性， 通过使用RNA表征MCF-7细胞中鉴定的蛋白质的活性的瞬时转染测定 干扰和染色质免疫沉淀分析。五个的分离和初步表征 _roteins产生了新的和令人兴奋的见解，以更好地了解这些ER相关的功能作用， 并提供了一个迷人的一瞥其活动的广度，其中包括组蛋白乙酰化， NA修复、肿瘤抑制和代谢加工。所获得的见解将有助于描述 雌激素和抗雌激素调节含有不同ERE序列的基因的转录，并增强我们的免疫功能。 了解乳腺肿瘤细胞以及正常组织（如子宫）的细胞反应性 和乳房对这些临床上重要的药剂的敏感性。

The steroid hormone estrogen plays a critical role in development and maintenance of female reproductive and mammary tissues, but is also involved in maintenance of cardiovascular, skeletal, and neural function, proliferation of breast cancer cells, and concentration of sperm in the male reproductive tract. Furthermore, estrogens and antiestrogens are widely used in regulating fertility, alleviating postmenopausal symptoms, and preventing and treating breast cancer. The biological effects of estrogen are initiated by binding to the intracellular estrogen receptor (ER) and inducing the ER to bind to estrogen response elements (EREs) residing in target genes. It is this interaction of ER with the ERE, in cooperation with multiple coregulatory proteins, that leads to changes in gene expression. During the previous award period, we demonstrated that individual EREs elicit distinct changes in ER conformation and that these ERE-induced changes in receptor conformation influence coactivator recruitment and ultimately alter gene expression. Thus, DNA, like a hormonal ligand, functions as an allosteric modulator of receptor conformation. The long term goal of this proposal is to elucidate mechanisms involved in regulating estrogen-responsive genes. We propose to isolate and identify proteins that associate with the ER in the presence of different EREs and hormones, to characterize Lhe effects of these proteins on the receptor's ability to bind to and activate transcription through different ERE sequences, and to elucidate mechanisms by which these proteins influence ER-mediated transactivation using molecular and biochemical analyses. We will test the physiological relevance of our in vitro observations and transient transfection assays by characterizing the activity of the identified proteins in MCF-7 cells using RNA interference and chromatin immunoprecipitation assays. The isolation and initial characterization of five _roteins has produced new and exciting insights to better understand the functional roles of these ER-associated _roteins and provided a fascinating glimpse of the breadth of their activities, which include histone acetylation, )NA repair, tumor suppression, and metabolic processing. The insights gained will help delineate how estrogens and antiestrogens regulate transcription of genes containing distinct ERE sequences and enhance our understanding of cellular responsiveness of mammary tumor cells, as well as normal tissues, such as the uterus and breast to these clinically important pharmaceutical agents.