Differentiation during Cleavage in Xenopus laevis. II
Development of Inductive Activity of the Organizer
1971 Volume 47 Issue 2 Pages 203-208
Details
1971 Volume 47 Issue 2 Pages 203-208
1) A piece of the dorsal marginal zone cut out from Xenopus laevis embryos at st. 6-10 was brought into close contact with a piece of presumptive ectoderm taken from early gastrula of the same species.
2) When these pieces were cultured for 48-60 hours keeping in contact with each other, neural induction took place in the specimens using the organizer at stages later than st. 61/2. With the organizer at st. 6, no induction was obtained.
3) When pieces of presumptive ectoderm was cultured alone for 48-60 hours being separated from the organizer after a short period of contact, neural induction was found only in the specimens using the organizer at st. 9 and 10.
4) It may be concluded that neural inducing agent is produced or activated at st. 9-10. Neural induction obtained with the organizer at st. 61/2-8 in the first experiment may be interpreted to have been caused by the agent brought into action by self-differentiation of the organizer during a long period of contact.
