MECHANISMS OF PRIMARY MESENCHYME MORPHOGENESIS

这项研究计划旨在了解细胞与细胞之间的关系， 动物形态发生过程中的细胞-基质相互作用。 分析 形态发生机制是我们理解胚胎发育的核心。 发展 拟议的研究探讨了形态发生的 初级间充质细胞（PMC），海洋中的迁移细胞群 海胆胚胎 这些细胞经历一系列可预测的运动 可以在体内直接观察到，并且可以进行生物化学和 免疫学分析 该项目的具体目标有三个方面： 1）研究PMC方向性的机制 迁移，通过包括分离胚胎 细胞外基质，PMC的显微操作，UV消融细胞 显微外科和电子显微镜，2）分析分子 发生在PMC和它们的底层之间的相互作用， 胚基层 我们将产生多克隆和单克隆 抗基底膜的抗体，并使用这些试剂来分析 PMC期间抗原决定簇的空间分布 迁移 我们也将使用这些试剂来寻找底物 在PMC迁移中具有功能作用的分子，通过显微注射 将抗体植入活的胚胎中， 3）检测PMC过程中细胞间的相互作用 形态发生 我们会用生化免疫和显微手术 方法来阐明机制，其中PMC防止继发性 间充质细胞（SMC）表达成骨表型。 我们将 重点放在事件的时间在这种互动和性质的 由PMC发送的信号。 此外，我们将努力开发 体外研究PMC-SMC相互作用。

This research program is directed at an understanding of cell-cell and cell-substratum interactions during animal morphogenesis. An analysis of morphogenetic mechanisms is central to our understanding of embryonic development. The proposed research examines the morphogenesis of the primary mesenchyme cells (PMCs), a population of migratory cells in the sea urchin embryo. These cells undergo a predictable sequence of movements that can be directly observed in vivo and are amenable to biochemical and immunological analysis. The specific goals of the project are threefold: 1)To examine the mechanisms that underlie the directionality of PMC migration, by a combination of approaches including isolation of embryonic extracellular matrices, micromanipulation of PMCs, cell ablation by UV microsurgery, and electron microscopy, 2)To analyze the molecular interactions that take place between the PMCs and their substratum, the embryonic basal lamina. We will generate polyclonal and monoclonal antibodies against the basal lamina and use these reagents to analyze the spatial distribution of antigenic determinants during the period of PMC migration. We will also use these reagents to search for substrate molecules that have a functional role in PMC migration, by microinjecting the antibodies into living embryos and by testing their effects on PMCs migrating in vitro, 3) To examine cell-cell interactions during PMC morphogenesis. We will use biochemical, immunological, and microsurgical methods to elucidate the mechanism by which the PMCs prevent secondary mesenchyme cells (SMCs) from expressing a skeletogenic phenotype. We will focus on the timing of events during this interaction and the nature of the signal transmitted by the PMCs. In addition, we will attempt to develop and in vitro system to study the PMC-SMC interaction.