Molecular mechanisms of oocyte and sperm maturation-inducing hormone

卵母细胞和精子成熟诱导激素的分子机制

基本信息

批准号：
08454266
负责人：
NAGAHAMA Yoshitaka
金额：
$ 5.06万
依托单位：
Okazaki National Research Institutes, National Institute for Basic Biology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1996
资助国家：
日本
起止时间：
1996 至 1997
项目状态：
已结题

项目摘要

This study was designed to investigate the molecular mechanism of oocyte and sperm-maturation inducing hormone (l7alpha, 20beta-dihydroxy-4-pregnen-3-one) in fish gonads. l7alpha, 20beta-Dihydroxy-4-pregnen-3-one is biosynthesized by the action of a steroidogenic enzyme, 20beta-hydroxysteroid dehydrogenase (20beta-HSD) from 17alpha-hydroxyprogesterone. We first isolated cDNA clones encoding ayu (Plecoglossus altivelis) and medaka (Oryzias latipes) 20beta-HSD.Using the ayu 20beta-HSD cDNA clone as a probe, we isolated two different 2Obeta-HSD like cDNAs from rainbow trout (Oncorhynchus mykiss) ovarian follicles. cDNA and genomic DNA analysis show that the two 20beta-HSDs are encoded in two different genes. Northern blot analysis and RT-PCR show that these two are expressed in different tissues. In vitro expression of the two cDNAs in E.colienabled us to establish that the product of one (type A) of the two cDNAs has the ability to convert 17alpha-hydroxyprogesterone to 17alpha, 2Obeta-dihydroxy-4-pregnen-3-one. 20beta-HSD gene expression was markedly enhanced when granulosa cells isolated from postvitellogenic follicles were incubated with gonadotropin. Furthermore, it is of importance to note that type A gene, but not type B gene, is inducible in granulosa cells by gonadotropin stimulation. Since 20beta-HSD type A exhibits 20beta-HSD activity, the enhanced expression of 20beta-HSD type A gene increases the conversion of 17alpha-hydroxyprogesterone to 17alpha, 2Obeta-dihydroxy-4-pregnen-3-one. These data demonstrate that the expression of 20beta-HSD is controlled by gonadotropin. The effects of gonadotropin on the promoter regions of 20beta-HSD genes will provide further understanding of steroid and protein hormone modulation of steroidogenic enzymes.

这项研究旨在研究卵母细胞和精子成熟的分子机制诱导激素（L7alpha，20beta-dihydroxy-4-4-Pregnen-3-One）。 L7Alpha，20Beta-dihydroxy-4-Pregnen-3-One通过类固醇生成酶，20Beta-羟基固醇脱氢酶（20Beta-HSD）的作用，从17Alpha-Hydroxyprogyprogyprogyprogyprogyprogyprogyprogyprogyprogyprogyprogyprogyprogstrogstrogatone中进行了生物合成。我们首先分离了编码Ayu（plecoglossus altivelis）和Medaka（oryzias latipes）20Beta-HSD的cDNA克隆。使用Ayu 20beta-HSD cDNA克隆作为探针，我们隔离了两个不同的2obeta-hsd，从彩虹Trout（Oncorhirhirynchus mykiss Mykisriant）中隔离了两个不同的2obeta-hsd。 cDNA和基因组DNA分析表明，两个20BETA-HSD被编码为两个不同的基因。 Northern印迹分析和RT-PCR表明，这两个在不同的组织中表达。在E.Colienabled的情况下，两种cDNA的体外表达是确定两个cDNA中一个（A型）的乘积可以将17Alpha-羟基耐糖酮转换为17Alpha，2obeta-dihydydroxy-4-4-pregnen-3-3-One。当从视力后卵泡分离的颗粒细胞与促性腺激素孵育时，20BETA-HSD基因表达显着增强。此外，重要的是要注意，促性腺激素刺激在颗粒细胞中诱导了A型基因而不是B型基因。自20BETA-HSD A型表现出20BETA-HSD活性以来，20BETA-HSD A型基因的表达增强了17Alpha-Hydroxyprogesterone typer type a型基因向17Alpha，2obeta-dihydroxy-4-4-4-Pregnen-3-3-one。这些数据表明，20Beta-HSD的表达受促性腺激素控制。促性腺激素对20BETA-HSD基因启动子区域的影响将进一步了解类固醇激素酶的类固醇和蛋白质激素调节。