Fig. 4. Endocrine development in PMycKO pancreata. Immunofluorescence staining for insulin (A,B, arrows) in E13.5 dorsal pancreatic buds of wild-type and PMycKO sections. (C-J) Sections of E18.5 wild-type and PMycKO embryos were analyzed for expression of endocrine markers by immunostaining (brown, arrows). (K-P) X-gal stained sections of E18.5 Ptf1a-cre(ex1);R262R and PMycKO;R26R pancreata were immunostained for glucagon. (Q,R) The β and cell masses were determined from anti-insulin- and anti-glucagon-stained multiple sections as described in the Materials and methods section. Inserts in I and J represent a 2x and a 4x enlargement respectively. Scale bar: 50 µm.