FGF SIGNALING AND ZINC FINGER PROTEINS IN GONAD DEVELOPMENT AND REPRODUCTION

FGF 信号传导和锌指蛋白在性腺发育和生殖中的作用

• 批准号: 8360168
• 负责人: ZI-JIAN LAN
• 金额: $ 19.45万
• 依托单位: UNIVERSITY OF LOUISVILLE
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-06-01 至 2012-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8360168
• 关键词: 1-Phosphatidylinositol 3-Kinase; 3-Phosphoinositide Dependent Protein Kinase-1; Anabolism; Androgens; Attenuated; Cells; Centers of Research Excellence; Defect; Development; Disease; Enzyme Gene; Estrogens; Estrous Cycle; Etiology; Female; Fertility; Fibroblast Growth Factor; Funding; Genomics; Gonadal structure; Gonadotropins; Grant; Human; Lead; Luteinizing Hormone; Molecular; Mutant Strains Mice; National Center for Research Resources; Oocytes; Ovarian; Ovary; Ovulation; PTEN gene; Patients; Phosphorylation; Physiological; Play; Polycystic Ovary Syndrome; Predisposition; Principal Investigator; Production; Proteins; Proto-Oncogene Proteins c-akt; Reproduction; Research; Research Infrastructure; Resources; Role; Signal Pathway; Signal Transduction; Signaling Molecule; Small Interfering RNA; Source; Syndrome; United States National Institutes of Health; Weight; Zinc Fingers; cost; granulosa cell; in vivo; inhibitor/antagonist; interstitial cell; microbial alkaline proteinase inhibitor; mutant; premature; response; theca cell; young adult

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Characterization of the in vivo function of phosphatidylinositol 3-kinase (PI3K) signaling in theca and interstitial (TI) cells was our research focus in the past year of COBRE support. Theca cells are differentiated from ovarian interstitial cells. The major function of theca cells is to produce androgen for estrogen biosythesis and genomic action in granulosa cells. The principal disorder associated with theca cells is polycystic ovary syndrome (PCOS) in which an excess of androgen and other ovarian defects are often observed. However, the in vivo function of signaling pathway(s) key for androgen production in theca and interstitial (TI) cells in the ovary remains to be characterized, as well as the etiology of PCOS. Phosphatase and tensin homolog (Pten) is a negative regulator of PI3K signaling. Recent studies of Pten and other PI3K signaling molecules have shown that PI3K signaling (especially in the oocyte) plays a critical role in normal ovarian development and female fertility. However, the in vivo function of this signaling in TI cells remains to be characterized. To explore the function of PI3K signaling in TI cells in vivo, we have generated TI-cell specific Pten mutant (tPtenMT) mice. Increased phosphorylation of PI3K signaling downstream molecules such as 3-phosphoinositide-dependent protein kinase 1 (PDK1) and protein kinase B (AKTs) were observed in tPtenMT ovaries, indicating that deletion of Pten in TI cells causes an overactivation of PI3K signaling in the ovary. More importantly, premature loss of female fertility with aberrant estrous cycle and natural ovulation were observed in tPtenMT mice. These physiological defects in tPtenMT mice were due to abnormal ovarian development, as there existed a variety of histological defects in the ovary (e.g., ovary enlargement). Abnormalities displayed in tPtenMT ovaries should result from deletion of Pten in TI cells, and the primary defect should be in TI cells. To support this, androgen excess was observed in tPtenMT mice and elevated expression of Lhcgr and several steroidogenic enzyme genes key for androgen biosynthesis in tPtenMT ovaries and TI cells, as well as in luteinizing hormone (LH)-treated Pten-siRNA lentiviral knockdown TI cells. LHCGR is located on a recently identified PCOS susceptibility locus. Modulation of the LH and Lhcgr action in androgen production by PI3K signaling in TI cells could be an underlying etiology of certain types of PCOS. Consistent with this hypothesis, the abnormalities displayed in young adult tPtenMT mice mimic PCOS in humans. Like PCOS patients, tPtenMT mice were able to ovulate in response to gonadotropins. Moreover, API-2, a specific AKT inhibitor, was able to attenuate the ovary enlargement and the increase of ovary weight displayed in young adult tPtenMT mice. Together, our results suggest that Pten in TI cells is critical for normal ovarian development and female fertility and that overactivation of PI3K signaling in TI cells can lead to development of PCOS-like syndrome in young adulthood.

这个子项目是利用资源的许多研究子项目之一。 由NIH/NCRR资助的中心拨款提供。对子项目的主要支持 子项目的首席调查员可能是由其他来源提供的， 包括美国国立卫生研究院的其他来源。为子项目列出的总成本可能 表示该子项目使用的中心基础设施的估计数量， 不是由NCRR赠款提供给次级项目或次级项目工作人员的直接资金。 在过去一年的Cobre支持中，膜和间质(TI)细胞中磷脂酰肌醇3-激酶(PI3K)信号的体内功能表征是我们的研究重点。卵泡膜细胞是从卵巢间质细胞分化而来的。卵泡膜细胞的主要功能是在颗粒细胞中为雌激素的生物合成和基因组作用产生雄激素。与卵泡膜细胞相关的主要疾病是多囊卵巢综合征(PCOS)，在PCOS中经常观察到雄激素过剩和其他卵巢缺陷。然而，卵巢膜和间质(TI)细胞中雄激素产生的信号通路(S)的体内功能以及多囊卵巢综合征的病因仍有待研究。磷酸酶张力蛋白同源物(Pten)是PI3K信号的负调节因子。最近对Pten和其他PI3K信号分子的研究表明，PI3K信号(特别是在卵母细胞中)在正常卵巢发育和女性生育中发挥着关键作用。然而，该信号在TI细胞中的体内功能仍有待研究。为了探讨PI3K信号在体内TI细胞中的作用，我们培育了TI细胞特异性Pten突变体(TPtenMT)小鼠。在tPtenMT卵巢中观察到PI3K信号下游分子如3-磷酸肌醇依赖的蛋白激酶1(PDK1)和蛋白激酶B(AKTS)的磷酸化增加，这表明在TI细胞中Pten的缺失导致卵巢中PI3K信号的过度激活。更重要的是，在tPtenMT小鼠中观察到了雌性生育能力的过早丧失和发情周期和自然排卵的异常。TPtenMT小鼠的这些生理缺陷是由于卵巢发育异常所致，因为卵巢存在各种组织学缺陷(如卵巢增大)。TPtenMT卵巢中显示的异常可能是由于TI细胞中的Pten缺失所致，而主要的缺陷应该是TI细胞中的缺陷。为了支持这一点，在tPtenMT小鼠中观察到雄激素过剩，在tPtenMT卵巢和TI细胞以及黄体生成素(LH)处理的Pten-siRNA慢病毒击倒TI细胞中，Lhcgr和几个雄激素生物合成关键的类固醇生成酶基因的表达增加。LHCGR位于新近发现的PCOS易感基因座上。在TI细胞中，PI3K信号通过调节黄体生成素和促性腺激素释放激素的作用，可能是某些类型多囊卵巢综合征的潜在病因。与这一假设一致的是，年轻成年tPtenMT小鼠的异常表现与人类的多囊卵巢综合征相似。像PCOS患者一样，tPtenMT小鼠能够对促性腺激素做出反应而排卵。此外，AKT特异性抑制剂API-2能抑制tPtenMT幼鼠的卵巢增大和卵巢重量增加。综上所述，我们的结果表明，TI细胞中的Pten对正常卵巢发育和女性生育至关重要，TI细胞中PI3K信号的过度激活可能导致青年时期PCOS样综合征的发生。