Planar cell movements and axial patterning preceding mammalian gastrulation

哺乳动物原肠胚形成之前的平面细胞运动和轴向模式

• 批准号: 30327495
• 负责人: Professor Dr. Christoph Viebahn
• 金额: --
• 依托单位: Institut für Anatomie und Embryologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2006
• 资助国家: 德国
• 起止时间: 2005-12-31 至 2010-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/30327495?language=en
• 关键词: Planar; cell; movements; axial; patterning

Well balanced cellular proliferation and migration are basic prerequisites for the development of the specific shape of an embryo or of its body parts. Molecular mechanisms of these processes are well described in many organisms at various developmental stages, but immediately preceding gastrulation, which irrevocably fixes the basic body plan, both aspects of cellular behaviour are still ill-defined, especially for the mammalian embryo. With their unique sequence of initial axial differentiation, mammals may in fact employ novel characteristics and combinations of proliferation and migration. The present project uses the late implantation and the superficial position and flat architecture of the embryoblast in the rabbit to analyse videomicroscopically all cell movements in the dorsal cell layer (epiblast) immediately prior to gastrulation in situ. Patterns of cellular movement will be compared with the expression patterns of extracellular matrix molecules and of members of the Wnt and nodal signalling cascades, which are known to regulate cell movements (in the planar cell polarity pathway, for example). Using the anterior margin of the embryonic disc as a landmark and agents modifying the Wnt signalling cascades, changes of single cell or cell sheet movements or of cellular division planes will be analysed. In addition, experimental outcomes on axial patterning, i.e. anterior vs. posterior differentiation, will be analysed using marker genes such as ANF and Brachyury. The results may help to define mechanisms central to early mammalian development.

良好平衡的细胞增殖和迁移是胚胎或其身体部位特定形状发育的基本先决条件。这些过程的分子机制在许多处于不同发育阶段的生物体中得到了很好的描述，但是在原肠胚形成之前，细胞行为的两个方面仍然不明确，特别是对于哺乳动物胚胎。由于它们独特的初始轴向分化序列，哺乳动物实际上可能采用新的特征以及增殖和迁移的组合。本项目使用后期植入和浅的位置和平面结构的胚胎母细胞在兔中分析所有的细胞运动在背细胞层（外胚层）前不久在原位原肠胚形成。细胞运动的模式将与细胞外基质分子和Wnt和节点信号级联的成员的表达模式进行比较，已知其调节细胞运动（例如，在平面细胞极性途径中）。将使用胚胎椎间盘的前缘作为标志和修改Wnt信号级联的试剂，分析单细胞或细胞片移动或细胞分裂平面的变化。此外，将使用标记基因（如ANF和Brachyury）分析轴向模式（即前分化与后分化）的实验结果。这些结果可能有助于确定早期哺乳动物发育的核心机制。