Fig. S3

Nodal-induced patterning in the animal pole mimics patterning in the margin.

(A) Flat-mounted germ ring stage embryos containing a Nodal-expressing clone stained for sox32 and lft2. This is the same embryo shown in Figure 3B left panel, but here the individual channels are shown. The Nodal-expressing clones are visualized with the dextran fluorescein (dex), and nuclei are visualized with DAPI. A merge of all channels is also shown. Note that sox32-positive cells are specified within the lft2-positive domain. In the bottom right corner, the number of representative embryos is depicted out of total analyzed embryos from two independent experiments.

(B) As in (A) but for lft2 and noto. noto expression is lower in the lft2 expressing domain. This is the same embryo shown in Figure 3B, middle panel.

(C) As in (A) but for lft2 and ta. Expression of ta is lower within the lft2 expressing domain. This is the same embryo shown in Figure 3B, right panel.

(D) As in (A) but for lft2 and fgf3. This is the same embryo shown in Figure 3C, left panel.

(E) As in (A) but for lft2 and fgf8a. This is the same embryo shown in Figure 3C, right panel.

(F and G) Examples of Nodal-expressing clones visualized with dextran fluorescein (dex) and stained for P-Erk. In very dense clones (3/21) it is clear that the cells expressing Nodal show a clear domain of low P-Erk staining (F). In other clones (18/21), the P-Erk staining is heterogeneous throughout (G). All scale bars are 100 μm.