Inducible cAMP Early Repressor in ovarian function

卵巢功能中诱导性 cAMP 早期抑制因子

• 批准号: 6708136
• 负责人: CARLOS A MOLINA
• 金额: $ 7.75万
• 依托单位: UNIV OF MED/DENT OF NJ-NJ MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-12-16 至 2005-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6708136
• 关键词: cyclic AMP; cyclins; female; follicle stimulating hormone; gene induction /repression; genetically modified animals; gonadotropins; granulosa cell; laboratory mouse; ovary; reproductive development; tetracyclines; tissue /cell culture; transcription factor

DESCRIPTION (provided by applicant): Normal expression of cyclin D2 is crucial for FSH-mediated ovarian granulosa cell proliferation. Cyclin D2-null female mice are sterile because the growth of the granulosa cells is impaired. In the normal mouse, FSH induces whereas LH inhibits cyclin D2 expression in granulosa cells. The elucidation of the regulatory pathways governing the expression of cyclin D2 will enhance our understanding of the normal development of granulosa cells. Others and we have found that Inducible cAMP Early Repressor (ICER) expression is induced by LH in granulosa cells. We demonstrated that in cultured naive granulosa cells, ICER repressed the activity of the cyclin D2 promoter. ICER was shown to mediate this repression through a putative cAMP response element (CRE) present in the cyclin D2 promoter. Moreover, ectopic expression of ICER in naive granulosa cells completely inhibits PKA-induced DNA synthesis. These data suggest that ICER is involved in the normal development of ovarian granulosa cells by controlling cyclin D2 expression. In order to test this hypothesis we propose to use inducible and granulosa-specific ICER transgenic mice. The following specific aims are proposed: 1) Biochemical validation of the mouse model; an inducible ovarian specific transgenic of ICER; 2) To determine the physiological effects of ICER induction by FSH on granulosa cells; 3) To determine whether ICER regulates cyclin D2 expression in vivo. The goal of this proposal is to complete the characterization of these mice and to obtain the necessary preliminary data to use these mice as a model system to study ICER regulation of ovarian development. The data generated in this proposal will form the basis for a future R01 application.

描述（由申请人提供）：细胞周期蛋白D2的正常表达对于FSH介导的卵巢颗粒细胞增殖至关重要。 细胞周期蛋白 D2 缺失的雌性小鼠是不育的，因为颗粒细胞的生长受损。在正常小鼠中，FSH 诱导颗粒细胞中细胞周期蛋白 D2 的表达，而 LH 则抑制其表达。阐明细胞周期蛋白 D2 表达的调控途径将增强我们对颗粒细胞正常发育的理解。其他人和我们发现诱导性 cAMP 早期阻遏蛋白 (ICER) 表达是由颗粒细胞中的 LH 诱导的。我们证明，在培养的初始颗粒细胞中，ICER 抑制细胞周期蛋白 D2 启动子的活性。 ICER 显示通过存在于细胞周期蛋白 D2 启动子中的推定 cAMP 反应元件 (CRE) 介导这种抑制。此外，ICER 在幼稚颗粒细胞中的异位表达完全抑制 PKA 诱导的 DNA 合成。这些数据表明 ICER 通过控制细胞周期蛋白 D2 的表达参与卵巢颗粒细胞的正常发育。为了测试这一假设，我们建议使用诱导型和颗粒特异性 ICER 转基因小鼠。提出以下具体目标：1）小鼠模型的生化验证； ICER 的诱导性卵巢特异性转基因； 2) 确定FSH诱导ICER对颗粒细胞的生理作用； 3)确定ICER是否调节体内细胞周期蛋白D2的表达。本提案的目标是完成这些小鼠的表征，并获得必要的初步数据，以使用这些小鼠作为模型系统来研究 ICER 对卵巢发育的调节。该提案中生成的数据将构成未来 R01 应用的基础。