Fig. 6

Knockdown of hnf-6 perturbs biliary development. (A and B) Left lateral view of 5 dpf control (A) and hnf-6 morphant larvae. Black arrowhead—liver. Liver size is identical in both larvae. (C–N) Confocal projections through the liver of WT and hnf-6 morphant larvae processed for cytokeratin IHC. (D–F) Three individual 5 dpf hnf-6 morphants: note the relative paucity of ducts compared with WT control (C). The morphant ducts are shorter and more dilated than the WT ducts. (G–N) Biliary morphology of 3.5 dpf-5 dpf WT (G–J) and hnf-6 morphant (K–N) larvae. Note that the biliary tree of the 3.5-dpf control larva consists of short, isolated ductlike structures. Diffuse cytokeratin immunoreactivity is also present in adjacent cells (G). By 4 dpf (H), more distinct ducts are evident, but they remain isolated. By 4.5 dpf (I), the ducts have become longer, and some interconnecting ducts are apparent. These features are more elaborate at 5 dpf (J); long continuous ducts with numerous interconnecting branches and terminal ductules are present throughout the liver at this stage. While morphant ducts at 3.5 dpf (K) and 4 dpf (L) are similar to control, at 4.5 dpf (M) and 5 dpf (N) the ducts are less dense and the interconnecting ducts and terminal ductules do not appear.