XB-IMG-77452
Xenbase Image ID: 77452
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Fig. S1. Non-neural ectoderm is required for complete NTC. (A-F) Dorsal explants were excised from early neurula embryos (stage 13) with (large explant) or without (small explant) non-neural ectoderm (A,B) and cultured until the late neurula stage (stage 20; C-F). Transverse sections show that the NT of the large explant was closed (F, arrow) whereas that of the small explant was still open (H, arrowhead), although apical constriction occurred normally (F, inset). (G-R) In situ hybridization of dorsal explants and intact embryos. Dorsal explants at early (G-J) and late (K-N) neurula stages were subjected to in situ hybridization for the neural marker sox2 (G,I,K,M) and the epidermis (non-neural) marker epidermal keratin (H,J,L,N). The large explants included both neural and non-neural tissues (n=10), whereas the small explants consisted only of neural tissue (n=10). The expression patterns of sox2 and epidermal keratin in whole embryos at early (O,P) and late (Q,R) neurula stages are shown as controls (n=5). (S-W) Dorsal explant without mesoderm or endoderm. A dorsal large explant of an early neurula embryo including neural and non-neural ectoderm, but not mesoderm or endoderm (mesendoderm) was attached to the bottom of a fibronectin-coated dish (S) and cultured until intact siblings reached the late neurula stage (T). Most of the explants closed their NTs. Transverse section of the mesendoderm-free explant showed a closed NT at the midline (U,V). Although small remnants of mesodermal tissue were visible (V, asterisk), they were probably too small to generate the force necessary for NTC of the explant. Removal of the mesendoderm tissues was confirmed by RT-PCR (W). Expressions of the mesoderm marker myoDa and endoderm marker sox17 were significantly reduced. Scale bars: 500 in C,E,G-R; 100 in D,F,U,V. Image published in: Morita H et al. (2012) Copyright © 2012. Image reproduced with permission of the publisher and the copyright holder. This is an Open Access article distributed under the terms of the Creative Commons Attribution License. Larger Image Printer Friendly View |