CELL LINEAGES IN MAMMALIAN DEVELOPMENT

含有两个父本(双亲和雄激素)的小鼠胚胎 而两个母体(双亲雌核)原核则没有 发育完全，但植入后不久死亡。 这样的胚胎出现了植入前的发育 形态正常。雄激素发育的胚胎表现为 胚胎本身的发育，而雌核发育激素则因为 胚胎外发育不良和/或分化不良的 膜。这项提案的总体目标是分析 雌孕酮、雄激素和雌雄激素细胞间的相互作用 聚集嵌合体中的正常胚胎，从而确定 无论是细胞致死还是形态发生相互作用的失败 对发育障碍负有责任。我们建议建造 使用雄激素的各种组合聚集嵌合体， 雌核发育和正常的卵裂球。随后的发展 这样的胚胎将被监测，每个胚胎的参与 组件已确定。为了确定准确的 这种嵌合胚胎中每个细胞的原位衍生 将使用身份识别方法。我们建议使用胚胎 来自我们实验室已经开发的转基因小鼠品系。 外源DNA序列将通过以下方式在每个细胞的细胞核中检测到 用生物素化探针进行DNA原位杂交。由于每个 来自转基因胚胎的细胞携带特定的可检测到的 序列，每个组件的起源和贡献 嵌合胚胎很容易确定。通过比较空间 和数量分布的雌核发育、雄核发育和 胚胎内具有发育能力的正常细胞 各种嵌合体胚胎我们将确定父系的角色 和母体基因组在小鼠早期形态发生事件中的作用 发展。

Mouse embryos containing two paternal (biparental andogenones) and two maternal (biparental gynogenones) pronuclei do not complete development but die soon after implantation. Preimplantation development of such embryos appears morphologically normal. Androgenetic embryos display failure of development of the embryo proper while gynogenones fail because of poor growth and/or differentiation of extraembryonic membranes. The overall objective of this proposal is to analyze the interactions of cells from gynogenones, androgenones and normal embryos in aggregation chimeras, thus determining whether cell lethality or failure of morphogenetic interactions is responsible for developmental failure. We propose to construct aggregation chimeras using various combinations of androgenetic, gynogenetic and normal blastomeres. Subsequent development of such embryos will be monitored and participation of each component determined. In order to determine the exact derivation of each cell in such chimeric embryos, in situ identification methods will be used. We propose to use embryos from transgenic mouse lines already developed in our laboratory. Foreign DNA sequences will be detected in nucleus of each cell by in situ DNA hybridization using biotinylated probes. Since each cell derived from transgenic embryos carries specific detectable sequences, the origin and contribution of each component of the chimeric embryo can be easily determined. By comparing spatial and quantitative distribution of gynogenetic, androgenetic and normal cells within embryos with the developmental capacity of various chimeric embryos we will determine the role of paternal and maternal genome in early morphogenetic events during mouse development.