Regulation of blood and vascular cell differentiation in embryos

胚胎中血液和血管细胞分化的调节

基本信息

批准号：
13680802
负责人：
MAENO Mitsugu
金额：
$ 1.6万
依托单位：
NIIGATA UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2001
资助国家：
日本
起止时间：
2001 至 2002
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13680802/
关键词：
amphibia embryonic blood cells vascular endothelial cells BMP-4 FGF organizer induction differentiation

项目摘要

In order to determine the tissue interactions that propagate blood formation in amphibian embryogenesis, we used embryos that had the vegetal cytoplasm removed. These embryos displayed a marked enhancement of globin expression. Several lines of experimental evidence demonstrate the critical role of animal pole-derived ectoderm in blood cell formation: 1) Mesoderm derived from dorsal blastomeres injected with galactosidase mRNA (as a lineage tracer) expressed globin when interfaced with an animal pole-derived ectodermal layer: 2) Embryos in which the animal pole tissue had been removed by dissection at the blastula stage failed to express globin: 3) Exogastrulated embryos that lacked an interaction between the mesodermal and ectodermal layers failed to form blood cells, while, muscle cells were observed in these embryos. These observations suggest that default mesodermal cells need an additional BMP-4-dependent factor from the overlying ectoderm for further differentiation into a blood cell lineage.Further experiments were done to elucidate the relationship between blood and vascular cell differentiation in the ventral blood island mesoderm. Using Xtie-2, as a vascular cell maker, it was shown that BMP (bone morphogenetic protein) signal is essential for both blood and vascular cell differentiation. On the other hand, FGF (fibroblast growth factor) signal was shown to control the distinct localization of vascular and blood cells. Therefore this study suggests that the early steps of blood and vascular cell differentiation are regulated by a common BMP-4-dependent signaling; however, distinct factor(s) such as FGF are involved in different distribution of these two cell lineages.

为了确定两栖动物胚胎发生中传播血液形成的组织相互作用，我们使用了去除了植物细胞质的胚胎。这些胚胎显示珠蛋白表达显着增强。几条实验证据证明了动物极源性外胚层在血细胞形成中的关键作用：1) 注射半乳糖苷酶 mRNA（作为谱系示踪剂）的背卵裂球衍生的中胚层，在与动物极源性外胚层接触时表达珠蛋白： 2) 在囊胚阶段通过解剖去除动物极组织的胚胎未能表达珠蛋白： 3) 外原肠胚胚胎中胚层和外胚层之间缺乏相互作用，无法形成血细胞，而在这些胚胎中观察到了肌肉细胞。这些观察结果表明，默认中胚层细胞需要来自上层外胚层的额外 BMP-4 依赖性因子才能进一步分化为血细胞谱系。进行了进一步的实验以阐明腹侧血岛中胚层中血液和血管细胞分化之间的关系。使用 Xtie-2 作为血管细胞标记器，结果表明 BMP（骨形态发生蛋白）信号对于血液和血管细胞分化至关重要。另一方面，FGF（成纤维细胞生长因子）信号被证明可以控制血管和血细胞的独特定位。因此，这项研究表明，血液和血管细胞分化的早期步骤是由共同的 BMP-4 依赖性信号传导调节的。然而，不同的因子（例如 FGF）参与了这两种细胞谱系的不同分布。