Identification of genes expressed in Drosophila germline

果蝇种系中表达基因的鉴定

基本信息

批准号：
07680793
负责人：
KOBAYASHI Satoru
金额：
$ 1.47万
依托单位：
University of Tsukuba
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1995
资助国家：
日本
起止时间：
1995 至 1996
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07680793/
关键词：
Drosophila Pole Cell Germline Enhancer-trap Differential Display Polar granules 生殖系列 nanos遺伝子

项目摘要

In many animal groups, factors required for germline formation are localized in a histologically remarkable region in egg cytoplasm, called germ plasm. In Drosophila embryos, germ plasm is localized in the posterior pole region and is inherited in pole cells, the germ-line progenitors in this animal. Transplantation experiments have demonstrated that germ plasm contains factors with sufficient ability to form germ line. Germ plasm also contains a second localized activity that directs the formation of abdomen. Genetic analysis has revealed that a common mechanism directs the localization of the abdomen and germ-line forming factors to the posterior pole. The critical factor for abdomen formation is the product of the nanos (nos) gene.In this study, we show that nos is also esential for germ-line formation in Drosophila. Pole cells lacking nos activity are incapable of becoming functional germ cells because they fail to migrate into the gonads. In such pole cells, enhancer activation which normally initiates within the gonad begins prematurely during pole cell migration. Premature activation of genes in germline precursors may cause these cells to be incapable of following the normal germline developmental program.Furthermore, we have identified an untranslatable RNA,called Pgc, which is localized in germ plasm. Most pole cells in embryos produced by females expressing anti-sense Pgc RNA fail to complete migration and to populate the embryonic gonads, and females which develop from these embryos often have agametic ovaries. Our results support an essential role for Pgc RNA in germ line development.

在许多动物群体中，种系形成所需的因子位于卵细胞质中组织学上显着的区域，称为种质。在果蝇胚胎中，种质位于后极区域，并在极细胞（该动物的种系祖细胞）中遗传。移植实验证明，种质中含有足以形成种系的因子。种质还包含指导腹部形成的第二种局部活性。遗传分析表明，有一个共同机制将腹部和种系形成因子定位到后极。腹部形成的关键因素是nanos（nos）基因的产物。在这项研究中，我们表明nos对于果蝇种系的形成也是必需的。缺乏 nos 活性的极细胞无法成为功能性生殖细胞，因为它们无法迁移到性腺中。在此类极细胞中，通常在性腺内启动的增强子激活在极细胞迁移期间过早开始。种系前体基因的过早激活可能会导致这些细胞无法遵循正常的种系发育程序。此外，我们还鉴定了一种不可翻译的RNA，称为Pgc，它位于种质中。表达反义 Pgc RNA 的雌性产生的胚胎中的大多数极细胞无法完成迁移并填充胚胎性腺，并且从这些胚胎发育而来的雌性通常具有无配型卵巢。我们的结果支持 Pgc RNA 在种系发育中的重要作用。