Hematopoietic induction and respecification of A-P identity by visceral endoderm signaling in the mouse embryo.
Hematopoietic induction and respecification of A-P identity by visceral endoderm signaling in the mouse embryo.
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发表时间：
1998-12
期刊：
影响因子：
4.6
通讯作者：
Maria Belaoussoff;S. Farrington;M. H. Baron
中科院分区：
文献类型：
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作者：
Maria Belaoussoff;S. Farrington;M. H. Baron
发育中的胚胎的前后轴在原肠胚形成开始时随着原条的形成而在形态上变得明显。第一个中胚层细胞出现的地方，标志着胚胎的后部。为了研究非中胚层信号在小鼠胚胎中指定后（造血和内皮）细胞命运的潜在作用，我们设计了一种转基因外植体培养系统。我们发现，原始内胚层和相邻的胚胎外胚层或新生中胚层之间的相互作用所需的早期原肠胚造血和血管发生的启动。令人惊讶的是，原始内胚层信号可以将前（预期神经）外胚层重新指定为后中胚层命运，导致血液形成和内皮标志物活化。前外胚层的重编程不需要细胞接触，并且受阶段依赖性、短程、可扩散信号的影响。因此，原始内胚层信号传导是造血和血管发育的关键早期决定因素，并且在小鼠胚胎发生期间的前后图案化中起决定性作用。
The anteroposterior axis of the developing embryo becomes morphologically apparent at the onset of gastrulation with the formation of the primitive streak. This structure, where the first mesodermal cells arise, marks the posterior aspect of the embryo. To examine the potential role of non-mesodermal signals in specifying posterior (hematopoietic and endothelial) cell fates in the mouse embryo, we have devised a transgenic explant culture system. We show that interactions between primitive endoderm and adjacent embryonic ectoderm or nascent mesoderm are required early in gastrulation for initiation of hematopoiesis and vasculogenesis. Surprisingly, primitive endoderm signals can respecify anterior (prospective neural) ectoderm to a posterior mesodermal fate, resulting in formation of blood and activation of endothelial markers. Reprogramming of anterior ectoderm does not require cell contact and is effected by stage-dependent, short-range, diffusible signal(s). Therefore, primitive endoderm signaling is a critical early determinant of hematopoietic and vascular development and plays a decisive role in anterior-posterior patterning during mouse embryogenesis.