请问什么是“卵圆筒阶段”？

牙牙丫丫123

我在读文献的时候看到了胚胎发育时有这样一个时期“egg cylinder stage”，在网上得到的结果是“卵圆筒阶段”。请问这具体是一个什么样的时期。

naturalkillerce

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In preparation for gastrulation, the embryo must become asymmetric along both the proximal-distal axis and the anterior-posterior axis. The proximal-distal axis is formed when the cells of the embryo form the “egg cylinder,” which consists of the extraembryonic tissues, which give rise to structures like the placenta, at the proximal end and the epiblast at the distal end. Many signaling pathways contribute to this reorganization, including BMP, FGF, nodal, and Wnt. Visceral endoderm surrounds the epiblast. The distal visceral endoderm (DVE) migrates to the anterior portion of the embryo, forming the “anterior visceral endoderm” (AVE). This breaks anterior-posterior symmetry and is regulated by nodal signaling.

john7812x

2011-12-6 20:24 上传

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