CONTROLLING MECHANISMS IN MAMMALIAN REPRODUCTION

项目的总体目标是阐明复杂的 细胞和遗传控制机制之间的相互作用 调节哺乳动物发育的早期阶段。 期间 一系列的卵裂分裂，从受精卵到 胚泡，胚胎基因组的顺序激活发生 伴随着第一个明显的分化迹象， 滋养外胚层和胚胎组织的起源。 由 胚泡阶段，胚胎包含所有的谱系前体 胚胎和胚外组织。 的定性 这些早期和关键的分化事件，我们提出， 以下实验方法： 1)通过所有研究人员的共同努力，基因探针 反映每个发育阶段基因表达的基因组序列， 发展。 这些探针将用于识别 相应的基因产物，并开始开始分析其 功能 2)通过暂时或永久性地将特定的 基因和/或其产物，这些基因的功能作用 将被确定。 3)将对核移植胚胎进行分析，以确定 他们的发展失败的原因，并确定 基因参与。 这种方法的一部分将涉及分析 配子发生过程中的特异性和基因调控。 4)生长控制分子（包括生长调节分子）的作用 因子及其受体和癌基因）调节生长 和早期胚胎的分化模式， 将研究滋养外胚层和内细胞团。 的作用 蛋白磷酸化在调节转录 将检查胚胎基因的活性。 5)细胞谱系的建立和细胞谱系特异性 将通过注射合适的DNA来探索基因表达 标记和用特异性探针进行原位杂交。 6)滋养外胚层、滋养层和内细胞的分化 将通过鉴定基因和基因产物来研究质量 通过确定它们的作用， 试图具体改变或废除这一第一 小鼠胚胎发生中的分化事件。 鉴于滋养外胚层组织的可及性， 特征性的一系列发展事件， 滋养外胚层形成。

The overall goal of the Program Project is to elucidate the complex interactions between the cellular and genetic control mechanisms which regulate the early stages of mammalian development. During the series of cleavage division which leads from zygote to blastocyst, sequential activation of the embryonic genome occurs concomitantly with the first overt signs of differentiation of trophectoderm and the origins of embryonic tissues. By the blastocyst stage, the embryo contains the lineage precursors of all embryonic and extraembryonic tissues. To determine the nature of these early and crucial differentiation events, we propose the following experimental approaches: 1) Through the joint effort of all investigators, genetic probes which reflect the gene expression at each developmental stage will be developed. These probes will be used to identify the corresponding gene products and to begin the analysis of their function. 2) By transient or permanent introduction into embryos of specific genes and/or their products, the functional role of these genes will be determined. 3) Nuclear transfer embryos will be analysed to determine the reasons for their developmental failure and for identifying the genes involved. Part of this approach will involve analysis of specific and gene regulation during gametogenesis. 4) The role of growth controlling molecules (including growth factors and their receptors and oncogenes) in regulating the growth and differentiation patterns in early embryos including trophectoderm and inner cell mass will be studied. The role of protein phosphorylation in regulating the transcriptional activity of the embryonic gene will be examined. 5) Establishment of cell lineages and the cell lineage specific gene expression will be explored by injection of suitable DNA markers and by in situ hybridization with specific probes. 6) Differentiation of trophectoderm, trophoblast and inner cell mass will be studied by identifying genes and gene products specific for those tissues, by determining their role and by attempting to specifically alter or abolish this first differentiation event in mouse embryogenesis. In view of the accessibility of trophectoderm tissue, the readily characterized sequence of developmental events involved in trophectoderm formation.