A novel intracellular 7TM estrogen receptor in breast

雌激素是人体内的一种重要激素，调节许多不同的生理效应，包括 许多组织的生长、发育和体内平衡。雌激素在这一过程中起着至关重要的作用， 正常乳腺组织的发育，而对雌激素的反应性是最重要的因素之一。 乳腺癌患者预后和治疗的重要因素。其中许多属性具有 雌激素受体（ER）是一种可溶性的雌激素受体，在很大程度上起着配体激活的作用。 转录因子我们已经描述了一种新的细胞内，7跨膜，G蛋白- 偶联雌激素受体（GPR 30），我们建议与ER一起调节细胞和组织 对雌激素的反应我们发现GPR 30主要存在于内质网中， 网状细胞。目的1的目标是确定GPR 30内调节其细胞位置的序列。 我们还开发了一种新的荧光雌激素衍生物家族，其结合ER和 GPR30。在目标2中，我们将使用这些荧光雌激素来开发基于细胞的雌激素结合试验， GPR 30，并确定一组雌激素相关化合物的结合特异性和亲和力。 最近，我们已经确定了乳腺癌中新的GPRSO介导的信号转导途径， 细胞3，4，5-三磷酸磷脂酰肌醇的核积累是由雌激素介导的 通过GPR 30的表皮生长因子受体（EGFR）的反式激活。目标3的目标是调查 涉及EGFR反式激活的EGFR磷酸化和内化机制， 导致转录激活和细胞生长控制。最后，我们建立了GPR 30的菌落 裸小鼠来剖析GPR 30在乳房生长和发育中的体内功能。在目标4中，我们 表征野生型小鼠中的GPR 30表达并分析GPR 30缺失小鼠的表型。我们将 还表征了其中GPR 30和经典ER均已缺失的小鼠的表型。 有了这些工具，我们可以在基因定义的 背景提出的实验将是非常宝贵的，在定义这种新的雌激素的作用- 在正常发育中雌激素介导的生长、增殖和分化中的反应性受体， 以及肿瘤进展和乳腺癌的治疗。

Estrogen is a crucial hormone in the human body, regulating many diverse physiological effects, including the growth, development and homeostasis of numerous tissues. Estrogen plays a critical role in the development of normal breast tissue, whereas responsiveness to estrogen represents one of the most important prognostic and therapeutic factors for patients with breast cancer. Many of these properties have been attributed to a soluble receptor for estrogen (ER) that functions in large part as a ligand-activated transcription factor. We have characterized a novel intracellular, 7-transmembrane spanning, G protein- coupled estrogen receptor (GPR30) that we propose functions alongside ER to regulate cell and tissue responsiveness to estrogen. We have discovered that GPR30 resides predominantly in the endoplasmic reticulum. The goal of Aim 1 is to determine the sequences within GPR30 that regulate its cellular location. We have also developed a novel family of fluorescent estrogen derivatives that binds to both the ER and GPR30. In Aim 2 we will use these fluorescent estrogens to develop cell-based estrogen binding assays for GPR30 and determine the binding specificities and affinities of a collection of estrogen-related compounds. Recently, we have characterized novel GPRSO-mediated signal transduction pathways in breast cancer cells. The nuclear accumulation of phosphatidylinositol 3,4,5-trisphosphate is initiated by estrogen-mediated transactivation of epidermal growth factor receptor (EGFR) by GPR30. The goal of Aim 3 is to investigate the mechanisms involved in EGFR transactivation with respect to EGFR phosphorylation and internalization, leading to transcriptional activation and cell growth control. Finally, we have established a colony of GPR30 null mice to dissect the in vivo function of GPR30 in breast growth and development. In Aim 4, we will characterize GPR30 expression in wild type mice and analyze the phenotypes of GPR30 null mice. We will also characterize the phenotypes of mice in which both GPR30 and the classical ERs have been deleted. With these tools, we can address estrogen-responsive signaling of GPR30 in a genetically defined background. The experiments proposed will be invaluable in defining the roles of this novel estrogen- responsive receptor in estrogen-mediated growth, proliferation, and differentiation in normal development as well as in neoplastic progression and the treatment of breast cancer.