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.