Expression of insulin but not glucagon or Somatostatin, is lost following prodrug dependent β cell ablation. (A – C) Marker analysis on ins:nfsB-mCherry untreated control embryos or embryos treated with Met from 56hpf to 80hpf (D to F). In situ hybridization with riboprobes to detect the following transcripts: insulin (ins) (A, D); glucagon (gcg) (B, E). Immunofluorescence detection of Somatostatin protein, using confocal microscopy, (C, F). Presence of the NTR-mCherry fusion protein can be seen in the control embryo (C) as red fluorescence, but is lost following ablation (F).