Fig. 5. Mammary buds 1, 2, 3 and 5 are not detected in the Fgf10–/– embryos. Whole-mount in situ hybridization on Fgf10–/– and wild-type embryos at E11.5 and E12.5 with dig-labeled antisense riboprobe for Lef1. B, D, F and I are high magnification views of the boxed areas in A, C, E and H respectively. (A) Lef1 is expressed in the mammary placodes at E11.5. Note that only mammary placodes 3 and 4 are clearly visible. (B) Mammary placode 4. (C) Lef1 expression is not detected in mammary placodes 1, 2, 3 and 5. Note Lef1 expression as a line in the area corresponding to mammary placode 4 (dotted box). (E) Lef1 expression at E12.5 in wild-type embryo showing expression in the epithelium of the mammary bud. Note that only mammary buds 2, 3 and 4 are visible. (F) Mammary bud 4. (G) Hematoxylin-eosin staining of mammary bud 4. (H) Lef1 expression in the Fgf10–/– embryo shows that only mammary bud 4 is detected (dotted box). (J) Hematoxylin and Eosin staining of mutant mammary bud 4 showing a normal structure. Scale bar, A, 670 µm; B, 100 µm; C, 670 µm; D, 100 µm; E, 1050 µm; F, 150 µm; G, 14 µm; H, 1050 µm; I, 150 µm; J, 14 µm.
