Gli2 function in the E15.5 thymus. (A) Phenotype of E15.5 Gli2^−/− thymi (WT, n = 8; Gli2^+/−, n = 9; Gli2^−/−, n = 7). Bar chart shows the relative number of thymocytes on E15.5; error bars are SD. The difference between WT and Gli2^−/− was not statistically significant. Dot plot shows the relative proportions of DN3 and DN4 populations: Cells negative for CD3, CD4, CD8, and CD44 were analyzed for CD25 expression. Cells positive for CD25 (DN3) and negative for CD25 (DN4) were gated separately. There were no significant differences in the proportion of DN3 and DN4 cells on E15.5. (B) Intracellular TCRβ (icTCRβ) expression in the E15.5 WT and Gli2^−/− thymus. Histogram plots of icTCRβ staining gated on DN3 (left) and DN4 (right) cells. Bar chart shows the relative percentage of icTCRβ on DN4 cells in E15.5 thymi. The difference between WT and Gli2^−/− was statistically significant (P = .02). (C) Bar charts to show degree of Vβ8 to Jβ2.7 (left chart) and Vβ5 to Jβ2.7 (right chart) rearrangement in E15.5 WT and Gli2^−/− thymocytes, assessed by Q-PCR.