Deletion of Sufu in the mesenchyme of limb buds with Dermo1-Cre mouse.

A-D: Whole mount in situ hybridization shows the expression of Sufu in fore- (A, B) and hind- (C, D) limb buds at E10.5. Noted the significantly reduced Sufu transcript in the Sufu^Dermo1Cre mutant limb buds (B, D), in comparison with the wild type (A, C). E-F: Immunohistochemical staining of the limb bud section using antibody against Sufu protein in wild type (E) and Sufu^Dermo1Cre(F). G-L: X-Gal staining of R26R/Dermo1-Cre. Whole-mount samples show Cre activity in the limb buds (G-I). J and K are sections of H and I, respectively. L is a horizontal section of I. Note the weaker staining in the core mesenchyme of the forelimb bud (arrowhead in J), compared to the hind limb bud (K). No Cre activity was detected in the limb bud epithelium (arrows in J and K). Mes: mesenchyme; Epi: epithelium; FL: forelimb bud; HL: hind limb bud.