The <i>exdpf</i> Gene Acts Genetically Downstream of RA during Exocrine Pancreas Development

<div><p>(A–G) In situ hybridization on 3 dpf embryos using a <i>carboxypeptidase A</i> (<i>cpa</i>) probe. (A) A WT control embryo. Note posterior expansion of exocrine pancreas. (B) An example of WT embryo treated with 10<sup>−6</sup> M RA. Note exocrine pancreas is restricted to the anterior part in the endogenous position. (C) An example of WT embryo injected with 2 ng of <i>exdpf</i> morpholino. Note exocrine pancreas is restricted to the head area in a similar fashion to (B). (D) An example of WT embryo injected with 2 ng of <i>exdpf</i> morpholino followed by treatment of 10<sup>−6</sup> M RA. Note no <i>cpa</i> expression was detected. (E) A WT embryo injected with 100 pg of <i>exdpf</i> mRNA. Note the increase of exocrine pancreas. (F) A WT embryo treated with 10<sup>−6</sup> M of DEAB. No <i>cpa</i> expression was detected. (G) An example of WT embryo injected with 100 pg of <i>exdpf</i> mRNA followed by treatment with 10<sup>−6</sup> M of DEAB. Note <i>cpa</i> expression was detected but not fully expanded posteriorly. All embryos were mounted anterior to the left, dorsal-lateral view. Scale bar: 50 μm.</p> <p>(H) A quantitative graph showing the percentage of embryos with <i>cpa</i> expression corresponding to (A–D). Y-axis, percentage of embryos with <i>cpa</i> expression. Mean ± SD.</p> <p>(I) A quantitative graph showing the percentage of embryos with <i>cpa</i> expression corresponding to (E–G) and control (A). Y-axis, percentage of embryos with <i>cpa</i> expression. Mean ± SD. In (H, I), percentage numbers are obtained from three independent experiments (<i>n</i> = 3). P value is from two-tail <i>t</i>-test for two samples assuming unequal variance (experimental group versus control).</p> <p>(J–O) In situ hybridization results using an <i>exdpf</i> or <i>trypsin</i> probe. (J and M) WT embryos treated with DMSO as controls. (K and N) WT embryos treated with 10<sup>−6</sup> M of RA. Note no <i>exdpf</i> or <i>trypsin</i> expression posterior to the white arrows. (L and O) WT embryos treated with 10<sup>−6</sup> M of DEAB.</p></div>