Kurth T, Hausen P
Max-Planck-Institut für Entwicklungsbiologie, Abteilung Zellbiologie, Spemannstrasse 35/V, 72076, Tübingen, Germany.
Mech Dev. 2000 Oct;97(1-2):117-31. doi: 10.1016/s0925-4773(00)00428-7.
The appearance of bottle cells at the dorsal vegetal/marginal boundary of Xenopus embryos marks the onset of blastopore formation. The conditions leading to this epithelial activity were investigated by inducing bottle cells ectopically in the animal region with VegT or different members of the transforming growth factor (TGF)-beta family. Morphological studies on the ectopic bottle cells indicate their close similarity to the endogenous bottle cells at the dorsal blastopore lip. The subepithelial cells of the induced animal region express mesodermal genes in a pattern reminiscent to that observed on the dorsal lip. Relating this expression pattern to the position of the ectopic bottle cells leads to the conclusion that bottle cells form in regions of high TGF-beta signalling. The specific inhibitory effects of cerberus on ectopically induced bottle cells revealed that nodal related growth factors are the intrinsic signals that elicit bottle cell formation in the normal embryo. In addition, fibroblast growth factor signalling is an essential precondition for this epithelial response as it is for mesoderm formation. We conclude that bottle cell formation in the epithelial layer of the gastrula is closely linked to mesodermal patterning in the subepithelial tissues.
非洲爪蟾胚胎背侧植物/边缘边界处瓶状细胞的出现标志着胚孔形成的开始。通过用VegT或转化生长因子（TGF）-β家族的不同成员在动物区域异位诱导瓶状细胞，研究了导致这种上皮活动的条件。对异位瓶状细胞的形态学研究表明，它们与背侧胚孔唇处的内源性瓶状细胞非常相似。诱导的动物区域的上皮下细胞以一种让人联想到在背侧唇处观察到的模式表达中胚层基因。将这种表达模式与异位瓶状细胞的位置相关联，得出的结论是瓶状细胞在高TGF-β信号区域形成。海妖蛋白对异位诱导的瓶状细胞的特异性抑制作用表明，与节点相关的生长因子是在正常胚胎中引发瓶状细胞形成的内在信号。此外，成纤维细胞生长因子信号传导是这种上皮反应的必要前提条件，就像它对中胚层形成一样。我们得出结论，原肠胚上皮层中的瓶状细胞形成与上皮下组织中的中胚层模式密切相关。
