Global down-regulation of epidermal ionocyte markers in foxi3a morphants. (A-F) Comparison of the epidermal ionocyte marker expression between wild-type (left panel) and foxi3a morphants (right panel). The expression of markers is completely abolished in the epidermal ionocyte lineage in foxi3a morphants. Note that the pronephric duct expressions in ndrg1, kcnj1, atp1a1a.2 and trpm7 were largely undisturbed, which shows that the foxi3a morphant phenotype specifically targets epidermal ionocytes. Na+,K+-ATPase-rich cell (NaRC) markers were ndrg1 (A), kcnj1 (B), and atp1a1a.2 (C). H+-ATPase-rich cell (HRC) markers were arg2 (D), trpm7 (E), and atp6voC (F). All embryos were scored at 24 hours post-fertilization (hpf).