Skip to main content
. 2022 Feb 15;38(7):110377. doi: 10.1016/j.celrep.2022.110377

Figure 1.

Figure 1

Embryonic hormone-expressing cells become islet endocrine cells

(A) Graphical design of the study aims The first stages of pancreas development (from E9.5 to E12.5) are defined by the formation of two endodermal primordia (the ventral and the dorsal bud), which progressively expand and branch to form the ductal tree. During this period, only a limited endocrine cell differentiation occurs. During the secondary transition (from E13.5 to term), there is a peak of endocrine unipotent precursor cells formation, and a rapid differentiation and emergence of hormone-expressing cells. These hormone+ cells delaminate from the ductal epithelia to generate clusters in the interstitia. The first islet-like structures are observed after birth.

(B) Transgenes required for tracing the lineages of Gcg-, Ins-, Sst-, and Ppy-expressing cells.

(C) Embryonic Gcg-, Ins-, Sst-, and Ppy-expressing cell labeling strategy. DOX, doxycycline; E7.5, embryonic day 7.5 after conception.

(D) Gcg+, Ins+, Sst+, and Ppy+ cells are efficiently YFP-labeled during embryogenesis. Immunofluorescence of YFP (green)-traced cells coexpressing glucagon (red, left panel), Insulin (red, mid-left panel), Somatostatin (red, mid-right panel), and Ppy (red, right panel) at postnatal day 0 (P0). Scale bars, 20μm. Quantification of the YFP-labeled hormone-expressing cells after birth (P0): 91.2 ± 1.9 (n = 5) of the Gcg+ cells are YFP-traced; 92.3 ± 1.1 (n = 4) of the Ins+ cells are YFP-traced; 96.2 ± 2.1 (n = 3) of the Sst+ cells are YFP-traced and 81.2 ± 1.4 (n = 5) of the Ppy+ cells are YFP-traced. P values: Gcg-YFPi, no DOX vs DOX = 0.0075; Mip-YFPi, no DOX vs DOX = 0.0079; Sst-YFPi, no DOX vs DOX = 0.0286; Ppy-YFPi, no DOX vs DOX = 0.0079. No Gcg+, Ins+, Sst+, and Ppy+ cells were YFP-tagged in absence of DOX. Whole pancreases were collected and analyzed. Data are shown as mean ± SEM. One representative biological replicate of an experiment is presented in the micrographs. Experiments were performed two or more times independently under identical or similar conditions. Quantification details are provided as Data S1A.