Fig. 7 Other possible signals involving the induction of the dorsal organizer by cultured cells. (A) Expression of fgf3, fgf8, mkp3 and dkk1 in each cell line by RT-PCR. No or little expression was detected in the cultured cells. (B–E) Whole-mount in situ hybridization for dkk1. Ectopic expression of dkk1 was induced in the implanted embryos (ZE6-1, 16 of 16 embryos, ZE6-1). (B) Unimplanted embryos. (C–E) ZE6-1 implanted embryos. Expression was observed in the marginal region in host embryos, but was not detected in animal pole region. (E) Longitudinal section of panel D with ventral to the left. Dotted lines surround the implanted cells. (B, C) Animal pole views. (D, E) Lateral views. (B–E) 5 hpf. Arrows indicate the ectopic expression of dkk1. Arrowheads indicate the cell implants. Scale bar, 100 μm.
Reprinted from Developmental Biology, 321(2), Hashiguchi, M., Shinya, M., Tokumoto, M., and Sakai, N., Nodal/Bozozok-independent induction of the dorsal organizer by zebrafish cell lines, 387-396, Copyright (2008) with permission from Elsevier. Full text @ Dev. Biol.