Kanéda Teruo
Biological Institute, Faculty of Science, Nagoya University, Chikusa-K, Nagoya 464, Japan.
Dev Growth Differ. 1980;22(6):841-849. doi: 10.1111/j.1440-169X.1980.00841.x.
Mesoderm formation in the presumptive trunk organizer was analyzed in gastrulae of Cynops pyrrhogaster. The presumptive trunk organizer showed little or no mesodermal differentiation in the beginning gastrula (0 h embryo). But as soon as the presumptive trunk organizer came into contact with the newly invaginated cranial archenteron roof, it rapidly formed mesoderm. This suggests that this differentiation was brought about by an inductive effect of the underlying cranial archenteron roof. For investigation of this possibility, the presumptive trunk organizer of 0 h embryos (Tr-0) and the newly invaginated cranial archenteron roof (presumptive pharyngeal endoderm and prechordal plate) of successive stages were cultured in isolation and by the sandwich technique. The newly invaginated presumptive pharyngeal endoderm and prechordal plate had no effect on mesoderm formation of the presumptive trunk organizer, and mesodermal differentiation of the combinations was similar to that of the Tr-0 alone. On the other hand, results showed that the prechordal plate, which came into contact with the still uninvaginated presumptive trunk organizer, stimulated dorsalisation of the weakly mesodermized trunk organizer. Based on these results, the stepwise process of mesoderm formation in the trunk organizer is discussed.
在日本林蛙原肠胚中分析了预定躯干组织者中的中胚层形成。在原肠胚早期（0小时胚胎），预定躯干组织者几乎没有或没有中胚层分化。但是，一旦预定躯干组织者与新内陷的颅原肠顶接触，它就会迅速形成中胚层。这表明这种分化是由下方的颅原肠顶的诱导作用引起的。为了研究这种可能性，将0小时胚胎的预定躯干组织者（Tr-0）和连续阶段新内陷的颅原肠顶（预定咽内胚层和前索板）进行单独培养和夹心培养。新内陷的预定咽内胚层和前索板对预定躯干组织者的中胚层形成没有影响，组合的中胚层分化与单独的Tr-0相似。另一方面，结果表明，与仍未内陷的预定躯干组织者接触的前索板刺激了弱中胚层化的躯干组织者的背化。基于这些结果，讨论了躯干组织者中胚层形成的逐步过程。
