Fig. 3

Fig. 3 Hdac1 is required for timely liver specification and differentiation. (A–J) In situ hybridisation analyses of hhex, prt/wnt2bb and cp expression in sibling and hdac1 mutant embryos; dorsal views, anterior to the top. (A, B) Wild type embryos express hhex in hepatoblasts at 24 hpf (bracket, A) and 48 hpf (arrowhead, B). Additionally, hhex is expressed in pancreatic tissue (asterisk). (C) hdac1 mutants lack hepatic hhex, though retain pancreatic expression at 24 hpf. At 48 hpf hhex expression is present in the liver of hdac1 mutants, although in a reduced domain (arrowhead, D). (E, F) Wild type embryos express prt/wnt2bb in the LPM at 26 hpf (bracket, E), however hdac1 mutants show reduced prt/wnt2bb expression (bracket, F). (G–J) cp is expressed in differentiating hepatocytes at 48 hpf and 4 dpf in wild type embryos (arrowheads, G, H). hdac1 mutants lack cp expression at 48 hpf (I); a subset of embryos express cp at 4 dpf (arrowhead, J). (K–N) Ventral projection of confocal stacks. Analysis of Tg(gutGFP)^s854 embryos (K, M; GFP not shown) and Tg(lfabp:dsRed;elastaseA:eGFP) embryos (L, N) stained for 2F11 (blue) and Prox1 (red) reveals that in wild type embryos 2F11 expression is heightened in the hepatopancreatic ducts at 48 hpf (arrowhead, K) and 4 dpf (arrowhead L). hdac1 mutant embryos express 2F11 throughout the organ-forming region at 48 hpf (M), however expression is heightened in the duct at 4 dpf (N). In addition, wild type embryos express dsRed in the liver and GFP in the pancreas at 3 and 4 dpf (L) while only a subset of hdac1 mutants express dsRed and GFP at 4 dpf (N).