Fig. 1

MGPY stains strongly the clusters (islets) of proliferating adult intestinal epithelial cells during T3-induced intestinal metamorphosis. Premetamorphic stage 54 tadpoles treated with 10 nM T3 for 0 (A), 3 (B), or 6 days (C) and were sacrificed 1 h after injection with EdU. Cross-sections of the intestine from the resulting tadpoles were double-stained for EdU and with MGPY. Higher magnifications of boxed areas in (A–C) are shown in (a′–c′) and (a″–c″). The approximate epithelium-mesenchyme boundary was drawn based on morphological differences between epithelial cells and mesenchyme cells in the pictures of the double-stained tissues, under enhanced contrast and/or brightness by using Photoshop, if needed (dotted lines). Note that the clusters (islets) of EdU labeled cells in the epithelium after 6 days of T3 treatment were strongly stained by MGPY (C, c″). Arrowheads indicate the clusters of proliferating cells or islets (c′)