Figure 10—figure supplement 1.

(A, B) Lateral projected confocal images of the yolk surface of 17hpf WT (A) and hai1a^hi2217/ti251 (B) embryos immunostained for p90RSK (Phospho-Thr³⁴⁸). (C) Quantification of immunofluorescent intensity of cytoplasmic levels of p90RSK (Phospho-Thr³⁴⁸) in cells over the yolk of 17hpf WT and hai1a^hi2217/ti251. Measurements were limited to keratinocyte cytoplasm by reading at sites between TP63-positive nuclei. n = 9 (three cells from three embryos each); Mann–Whitney test; **p<0.01. (D–G) Lateral projected confocal images of the tails of 48hpf hai1a^hi2217 embryos, untreated (D, F) or treated with GFX109203 to inhibit PKC (E) or dimethyl fumarate (DMF) (G) and then immunostained for p90RSK (Phospho-Thr³⁴⁸). Levels of cytoplasmic p90RSK-Thr³⁴⁸ are reduced by both inhibitors. (H, I) Lateral DIC images of hai1a^hi2217 embryos at 24hpf either untreated (H) or treated with 9 µM DMF (I). Locations of epidermal aggregates and loss of tail fin morphology in hai1a mutants, and their rescue by RSK inhibitor treatment are indicated by arrowheads. (J) Proportions of epidermal phenotypes from hai1a^{hi2217/hi2217} × hai1a^+/hi2217 determined at 24hpf and 48hpf following treatments with DMSO, BI-D1870, or DMF. n = 100; Chi-squared test; ***p<0.001. (K, L) Lateral projected confocal images of trunks of 48hpf hai1a^hi2217 embryos, untreated (K) or treated with 9 µM DMF (L), and then fluorescently immunostained for TP63. Scale bars: (A) = 200 µm; (D) = 100 µm.