Fig. 5

Pancreatic progenitors are increased in sept7b knockdown larvae.

(A–D) Pdx1-positive cells (red; arrow) in control MO-injected (A,C) and sept7b TBMO-injected (B,D) Tg(ptf1a:GFP) zebrafish larvae at 3 dpf. In (A,B) the exocrine pancreas (arrowhead) is visualized by ptf1a (green) and the nuclei are labelled with DAPI (blue). (C) and (D) are corresponding images visualizing Pdx1 only. (E) Pdx1-positive cells are significantly increased in sept7b knockdown larvae compared to control MO-injected larvae. (F) Schematic representation showing that control MO-injected larva show differentiation of Pdx1-positive pre-pancreatic progenitors, which give rise to mature insulin- and glucagon-positive β- and α-cells, respectively. The islet cells in sept7b TBMO-injected larva fail to differentiate and present bihormonal cells positive for both insulin and glucagon (see also Fig. 3). Scale bar: (A–D) (25 μm). Error bars represent mean ± SEM. *p ≤ 0.05.