Comparative study of extracellular fibrils on the ectodermal layer in gastrulae of five amphibian species.
Comparative study of extracellular fibrils on the ectodermal layer in gastrulae of five amphibian species.
复制标题
五种两栖动物原肠胚外胚层细胞外原纤维的比较研究。
作者：
N. Nakatsuji;K. Johnson
先前的研究表明，在原肠薄口瘤外胚层的内表面存在一个细胞外原纤维网络。原纤维网络沿胚孔-动物极轴排列表明原纤维网络通过接触引导引导原胚中迁移的中胚层细胞。我们还表明，这些原纤维可以通过外植的胚胎碎片沉积在基质上，并且以这种方式调节的基质支持定向细胞迁移。在这项研究中，我们发现胚胎中原纤维的出现与细胞向动物极点迁移的开始一致。所研究的三种尾尾动物（A. maculatum， A. mexicanum和Cynops pyrrhogaster）的胃原纤维具有相似的致密网络。非洲爪蟾原胚也有类似的原纤维，但与尾爪蟾胚胎相比，原纤维较少。原肠蛙的细胞外原纤维很少。无尾猿中原纤维的缺乏可能与迁移过程中中胚层细胞排列的差异有关。
Previous studies have shown the presence of a network of extracellular fibrils on the inner surface of the ectodermal layer of the Ambystoma maculatum gastrulae. The alignment of the network along the blastopore-animal pole axis has suggested that the network of fibrils guides the migrating mesodermal cells in gastrulae by contact guidance. We have also shown that these fibrils can be deposited on substrata by explanted embryonic fragments and that substrata conditioned in this manner support directed cell migration. In this study, we found that the appearance of the fibrils in the embryos coincides with the start of cell migration towards the animal pole. Gastrulae of three urodele species examined (A. maculatum, A. mexicanum and Cynops pyrrhogaster) have similar dense networks of fibrils. Xenopus laevis gastrulae also have similar fibrils but fewer fibrils compared to urodele embryos. Rana pipiens gastrulae have very few extracellular fibrils. The scarcity of the fibrils in anuran species may be related to the differences in arrangement of mesodermal cells during migration.