Mechanisms for Coelom formation : Binary dicision of the lateral plate mesoderm

体腔形成机制：侧板中胚层的二元决定

• 批准号: 14570027
• 负责人: FUNAYAMA Noriko
• 金额: $ 2.24万
• 依托单位: RIKEN (The Institute of Physical and Chemical Research)
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2002
• 资助国家: 日本
• 起止时间: 2002 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-14570027/
• 关键词: Lateral plate mesoderm; Somatopleural mesoderm; Splanchnopleural mesoderm; Epithelialization; SHH; Chick embryo; Cyclopamin; RNAi; 2本鎖RNA; knock down; cadherin6B; Pax6

Most triploblastic animals including vertebrates have a coelomic cavity that separates the outer and inner components of the body. The coelom is lined by two different tissue components, somatopleure and splanchnopleure, which are derived from the lateral plate region. Thus, the coelom is constructed as a result of a binary decision during early specification of the lateral plate. In this report we studied the molecular mechanisms of this binary decision. We first demonstrate that the splitting of the lateral plate into the two cell sheets progresses in an anteroposterior order and this progression is not coordinated with that of the somitic segmentation. By a series of embryological manipulations we found that the ectoderm underneath the primitive lateral plate is also required for the Splanchnopleural mesoderm. From the barrier experiment, it was suggested that this inductive activity is depend on the secreting factor(s) from lateral plate endoderm. We also show that the inductive activity is mediated by SHH molecules that are localized in the lateral endoderm. Evolutionary aspects of the coelom formation are also considered.

包括脊椎动物在内的大多数三胚层动物都有一个体腔，将身体的外部和内部分开。体腔由两种不同的组织组成，体侧板和脏侧板，这是来自侧板区域。因此，体腔的构建是在侧板的早期规范过程中二元决策的结果。在这份报告中，我们研究了这种二元决策的分子机制。我们首先证明，分裂成两个细胞片的侧板进展在一个前后顺序，这种进展是不协调的体节分割。通过一系列的胚胎学操作，我们发现原始侧板下的外胚层也是内脏侧中胚层所必需的。屏障实验表明，这种诱导活性依赖于侧板内胚层的分泌因子。我们还表明，诱导活性介导的SHH分子定位在侧内胚层。体腔形成的进化方面也被考虑。