Fig. 4. Embryonic expression of seam and non-seam epidermal markers. Wild-type expression patterns are shown in the left panels, expression in elt-5(RNAi) embryos is shown on the right. (A-F) Approximately threefold stage embryos carrying NR reporters. (A,B) nhr-75::GFP is expressed in seam cells in wild-type (A) but not in elt-5(RNAi) (B) embryos. (C,D) nhr-73::GFP is expressed at high levels in both wild-type (C) and elt-5(RNAi) (D) embryos. (E,F) nhr-77 is expressed at high levels in seam cells in wild-type (E) and weakly and sporadically in elt-5(RNAi) (F) embryos. In the elt-5(RNAi) embryo, a single seam cell shows a barely detectable level of GFP expression (arrow). (G,H) elt-3::GFP expression in wild-type and elt-5(RNAi) embryos at the 1.5-fold stage. JAM-1::GFP expression in adherens junctions was included to help in identifying seam cells. The arrows indicates two seam cells, H2 and V3, in G,H. (G) elt-3::GFP is expressed in all non-seam major epidermal nuclei, and is excluded from all seam nuclei in a wild-type embryo. (H) elt-5(RNAi) embryo showing ectopic expression of elt-3::GFP in seam cells. Eight seam nuclei show expression, two of which are indicated by the arrows. A gap in the adherens junction of H0 (arrowhead) reveals that the cell is undergoing fusion.