Figure 4.

Figure 4. eda and thyroid hormone (TH) regulate signaling ligand transcription in basal epidermal cells

(A) UMAP visualizations with wild-type cells in blue, eda mutant cells in yellow, and hypoTH cells in red highlighting the absence of scale-forming cell (SFC) and residual pre-SFC in skins of eda mutants and the absence of both populations in skins of hypoTH fish. Magenta asterisks mark differences in pre-SFC complements between eda mutant and hypoTH; other cell types designated in Figure 1C. (B) Heatmap visualization of cell type abundance shows that eda mutants retain more pre-SFCs than hypoTH fish. (C) Optical sections and (D) schematic representations of wild-type, eda mutant and hypoTH skin, visualized in ET37:EGFP transgenics, showing abundance of SFC in wild-type, a thin layer of pre-SFC in eda mutants, and lack of pre-SFC in hypoTH skin. dm, dermal mesenchyme; h, hypodermis; s, stromal collagen. Scale bar, 10 μm (C).