Figure 6. Nodal promotes ex vivo C and E independent of mesoderm.

(A) Diagram of the time course of SB-505124 (SB) treatment of ndr2-expressing explants. (B) Representative images of WISH for the transcripts indicated in explants from WT embryos injected with 10 pg ndr2 RNA, treated with SB at the indicated time points, and fixed at the equivalent of the 2–4 somite stage from four independent trials. (C) Length/width ratios of explants shown in (B). Each dot represents a single explant, black bars are median values; p<0.0001, Mann-Whitney test. (D) Diagram of the time course of SB treatment of ndr2-expressing explants followed by washout. (E) Representative images of WISH for the indicated transcripts in explants from WT embryos injected with 10 pg ndr2 RNA, treated with SB at the indicated time points, and fixed at the equivalent of the 2–4 somite stage from four independent trials. (F) Length/width ratios of explants shown in (E), as in panel (C). ****p<0.0001, Mann-Whitney test. Scale bars are 300 μm.

Figure 6—figure supplement 1. Nodal inhibitor treatment of intact embryos.

Representative images of WISH for the indicated transcripts in WT embryos treated with DMSO or SB-505124 beginning at 4–8 hpf and fixed at the two-somite stage. The scale bar is 300 μm.

Figure 6—figure supplement 2. Time-course of Nodal inhibition in ndr2-expressing explants.

(A) Diagram of the time course of SB-505124 (SB) treatment of ndr2-expressing explants, as in Figure 6. (B) Representative images of WISH for the transcripts indicated in explants from WT embryos injected with 10 pg ndr2 RNA, treated with SB at the indicated time points, and fixed at the equivalent of the 2–4 somite stage from four independent trials.