MECHANISMS OF PRIMARY MESENCHYME MORPHOGENESIS

这项研究计划旨在了解细胞-细胞和 动物形态发生过程中细胞-底物的相互作用。一种分析 形态发生机制是我们理解胚胎的核心 发展。这项拟议的研究检查了细胞的形态发生。 初级间充质细胞(PMC)--海洋中的一类迁移细胞 海胆胚胎。这些细胞经历了一系列可预测的运动 可以在体内直接观察，并服从于生化和 免疫学分析。该项目的具体目标有三个方面： 1)检查PMC方向性的基础机制 通过多种方法的组合进行迁移，包括分离胚胎 细胞外基质、PMCs的微操作、紫外线消融细胞 显微外科和电子显微镜，2)分析分子 在PMC和它们的基质之间发生的相互作用， 胚胎基膜。我们将产生多克隆和单克隆 针对基底膜的抗体，并使用这些试剂分析 PMC期间抗原决定簇的空间分布 迁移。我们还将使用这些试剂来寻找底物 在PMC迁移中起功能作用的分子，通过显微注射 将抗体注入活胚胎并测试其对PMC的影响 体外迁移，3)观察PMC过程中细胞与细胞的相互作用 形态发生。我们将使用生化、免疫学和显微外科技术 方法阐明PMC预防继发疾病的机制 间充质细胞(SMCs)表达成骨表型。我们会 重点放在互动过程中事件的时间安排和 由PMC传输的信号。此外，我们还将尝试开发 体外系统研究PMC-SMC的相互作用。

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.