Fig. 6

Fig. 6 Induction of the dorsal organizer is unrelated to Activin signaling. (A) Expression of activin in each cell line by RT-PCR. activinβA was detected in the ZE6-1, ZE24-1, ZE120-1 cell lines, and Sertoli cell lines (ZtA6-6, ZtA6-12-1) and activinβB was detected in the ZE6-1 cell line and Sertoli cell lines (ZtA6-6, ZtA6-12-1). (B, D, F) Unimplanted; (C, E, G) ZE6-1 implanted embryos. (B, C) Embryos injected with lefty1. Secondary axis induced in the lefty1-injected embryos (C; 18 of 19 embryos, ZE6-1). (F, G) Whole-mount in situ hybridization for lefty1. We observed no ectopic expression of lefty1 in implanted embryos (G; n = 23). (B, C) Lateral views at 24 hpf. (D–G) Animal pole views at 6 hpf. e, eye of secondary axis; o.v., otic vesicle of secondary axis; t, tail of secondary axis. Arrowhead indicates the cell implants. The large arrows in G indicate the secondary axis. Scale bar, 100 μm.