Fig. 6

Two temporally defined roles for Nr5a2 during pancreas development. (A) Timed Cpd3 treatment reduces trypsin expression at 72 hpf for the 12-32 hpf and 50-72 hpf treatment windows, but not during the 33-50 hpf window. (B) Control (n=22/46), 12-32 hpf (n=19/36), and 33-50 hpf (n=14/25) treated fish all have the same percentage of fish with differentiated exocrine pancreas cells at 44 hpf, indicating that drug treatments do not alter the timing of initial exocrine cell differentiation. (C) Control (n=12/12), 12-32 hpf (n=11/11), and 33-50 hpf (n=14/14) treated fish all have similarly sized trypsin cell clusters at 56 hpf, demonstrating that initial exocrine pancreas differentiation is unaffected by previous nr5a2 inactivation. (D) Quantification of exocrine pancreas size (by area of trypsin expression at 72 hpf) demonstrates that the 12-32 hpf and 50-96 hpf Cpd3 treatment groups have significantly reduced exocrine pancreas sizes relative to controls. Exocrine pancreas size in the 33-50 hpf treatment group was not significantly altered by treatment (n>21 per group; for control vs. 12-32 hpf, p=0.007; for control vs. 33-50 hpf, p=0.09; for control vs. 50-72 hpf, p<0.0001; unpaired t-test). (E) Quantification of exocrine pancreas size by area of trypsin expression demonstrates that antagonist-induced exocrine pancreas reduction persists through 96 hpf for the 12-32 hpf and 50-96 hpf treatment categories. The size of the pancreas in 33-50 hpf treatment categories remains unchanged relative to the vehicle treated controls (n>13 per group; for control vs. 12-32 hpf, p=0.02; for control vs. 33-50 hpf, p=0.5929; for control vs. 50-72 hpf, p=0.037; unpaired t-test).