Retinoic acid elicits posterior insulin expression in cdx4 morphants. (A-C) Zebrafish embryos treated at shield stage and fixed at 24hpf. Brackets indicate the normal position of the pancreas in untreated wild-type and cdx4 morphant embryos. (D) Percentage of embryos expressing posterior ectopic insulin in response to RA treatment plus cdx4 knockdown. Average cell numbers (±s.d.) by treatment timepoint were as follows: 4.3hpf, 3.4±1.9; 5.3hpf, 2.6±1.7; 6hpf, 2.3±1.8; 7hpf, 1.7±0.6; 8hpf, 1.4±0.5. Sample sizes for RA-treated embryos, without Cdx4 MO injection, were a minimum of 25 embryos per timepoint. Bars represent the combined results of two independent experiments. Dorsal views, anterior to left. Magnification: 100x.
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