RPG: Regulation of Ovarian Aromatase in Teleosts

9306518 Petrino这项针对女性的研究计划资助研究了硬骨鱼在整个生殖周期中17b -雌二醇的周期性释放。它对卵母细胞生长（卵黄形成）至关重要，似乎在产卵模式的调节中具有编程作用。因此，对其周期合成规律的研究具有重要意义。在硬骨鱼的循环产卵活动和卵泡发育过程中，类固醇生成途径中酶活性的诱导、维持或调节的激素和分子机制尚未完全确定。这个项目的重点是卵巢芳香化酶，这是一种将睾酮转化为雌二醇所需的酶，它位于卵母细胞周围的卵泡（granolosa）细胞中。本初步研究的具体目的是：1)构建一个代表环卵硬骨鱼（Fundulus heteroclitus）卵巢mRNA的cDNA文库；2)利用特异性探针克隆和测序芳香化酶cDNA。测序后的酶片段可用于未来的研究，用于生成放射性探针，以检测促性腺激素刺激和卵泡发育下芳香化酶mRNA的水平。分离F. heteroclitus芳香化酶cDNA将有助于比较具有不同产卵行为模式的硬骨鱼物种，从而有助于更好地理解硬骨鱼循环繁殖过程中的调控机制。这些信息将有助于对脊椎动物卵巢生理学和生殖内分泌学的全面了解。＊＊＊

9306518 Petrino This research planning grant for women examines the periodic release of 17B-estradiol throughout the reproductive cycle of teleosts. It is crucial for oocyte growth (vitellogenesis) and appears to have a programming role in the regulation of spawning patterns. Therefore, it is of great interest to investigate the regulation of its periodic synthesis. The hormonal and molecular mechanisms of induction, maintenance or regulation of enzyme activity in the steroidogenic pathway during the cyclic spawning activity and follicle development in teleosts are not at all defined. This project focuses on ovarian aromatase, the enzyme required for the conversion of testosterone to estradiol that is located in the follicular (granolosa) cells surrounding the oocyte. The specific aims of this preliminary study are: 1) to construct a cDNA library, respresentative of ovarian mRNA from the cyclic spawner teleost Fundulus heteroclitus, and 2) to clone and sequence the cDNA for aromatase using specific probes. Segmants of the sequenced enzyme can then be used in future studies for generating radioactive probes necesaries to detect the levels of aromatase mRNA under gonadotropic stimulation and follicle development. Isolating F. heteroclitus aromatase cDNA will allow comparison amoung teleosts species that show a very differant pattern in spawning behavior, and thus it will contribute to a better understanding of the regulatory control mechanisms operating during cyclic reproduction in teleosts. This inforamtion will be helpful in an overall understanding of ovarian physiology and reproductive endocrinology in vertebrates. ***