FIG.1.
Expression of Axin2 mRNA during mouse embryogenesis. (A to C) Whole-mount in situ hybridization. At E7.5 (A), Axin2 is expressed throughout the posterior region of the embryo; at E8.5 (B), expression is seen in the rostral and caudal ends of the neural ectoderm. At E9.5 (data not shown) and E10.5 (C), expression is seen along the entire length of the dorsal neural tube, as well as in the branchial arches (arrowheads) and limb buds (arrows). (D to F) In situ hybridization to transverse sections. At E7.5 (D), Axin2 is expressed in both the primitive streak mesoderm (arrow) and the posterior embryonic ectoderm (arrowhead). The approximate orientation of panel D is shown by the dotted line in panel A. At E10.5 (E) and E11.5 (F), strong expression is seen in the roof plate of the neural tube, with progressively weaker expression in a stripe of cells extending ventrally. The approximate orientation of panel E is shown by the dotted line in panel C. (G to I) Sections of developing organs from E14.5 embryos. In the lung (G), expression is seen throughout epithelial component. In the gut (H), Axin2 is expressed specifically in the epithelium at the base of the nascent villi, where the crypts will later form. In the kidney (I), expression is seen specifically in the ureteric buds; inset, higher magnification of branching ureteric bud tip. Bars, 1 mm (A to C) and 0.1 mm (D to I).