Fig. 4.

Gli1 expression in the enthesis is initiated by SHH. (A,B) Skeletal preparations from control and Shh-GFPCre^−/− embryos at E14.5 demonstrate that, although limb morphology is greatly impaired in the mutant, proximal humerus morphology remains similar and the DT is formed. Arrowheads indicate the deltoid tuberosity. (C-D′) Fluorescent ISH for Gli1 mRNA on sections through the DT of E14.5 Shh-GFPCre^−/− (C-C′) and control (D-D′) embryos show that, in the absence of SHH signaling, Gli1 mRNA and expression in the DT enthesis is lost. C′ and D′ are magnifications of the boxed areas in C and D, respectively. Dashed line demarcates the enthesis. Scale bars: 50 µm.