Fig. 7

Bmp4 in Kupffer's vesicle is required for LR patterning. All embryos shown here were injected at the 512 cell stage to target the bmp4 MOs to the dorsal forerunner cells (DFC) that will form Kupffer's vesicle. (A, B) Ntl expression in 10 somite stage embryos marks Kupffer's vesicle. No difference in vesicle morphology was observed in DFC^{ctr MO}-injected embryos (A) compared to DFC^{bmp4 MO}-injected embryos (B). Lateral views of tail bud, arrowhead points to KV. (C, D) LR dynein (dnah9) is expressed in Kupffer's vesicle. No difference was observed in DFC^{ctr MO}-injected embryos (C) compared to DFC^{bmp4 MO}-injected embryos (D). Ventral views of tail bud at 1 somite stage, arrowhead points to Kupffer's vesicle. (E–H) Ectopic spw expression in the right LPM upon DFC^{bmp4 MO} injection (F) compared with DFC^{ctr MO}-injected embryos (E). No effect on spw expression was observed after DFC^{bmp2b MO} (G) or DFC^{bmp7 MO} (H) injection. Dorsal views of 18 somite stage embryos. (I–L) Lefty1 is expressed in the head region and in the notochord (arrow) at the 10 somite stage (I, J) and in the left heart field and notochord at the 22 somite stage (K, L). Lefty1 expression is absent from the notochord but normally present in the head region in DFC^{bmp4 MO}-injected embryos (J) when compared to of DFC^{ctr MO}-injected embryos (I). At the 22 somite stage lefty1 expression is absent from the DFC^{bmp4 MO}-injected embryos (L) compared to DFC^{ctr MO}-injected embryos (K). (I, J) Lateral view of 10 somite stage embryos. Arrow points to the lefty1 expression in the posterior notochord. (K, L) Dorsal views of 22 somite stage embryos. (M, N) Expression of lefty2 in the LPM is not affected in the DFC^{bmp4 MO}-injected embryos (N) compared to DFC^{ctr MO}-injected embryos (M). Dorsal views of 25 somite stage embryos.