Figure 10.

The iRL and eRL have differential-proliferative activity. Cell-proliferative activity in the iRL and eRL was studied with pulse-BrdU labeling and quantitative assessment at E15.5. A, The E15.5 RL is double labeled for Wls (red fluorescence) and BrdU (green fluorescence), and proliferative cells were observed in both the Wls⁺ iRL and Wls⁻ eRL. B, Proliferative indices are calculated for the iRL and eRL cell populations (n = 4 embryos), and proliferation activity is significantly different between the two populations of cells. Error bars represent SE; *p < 0.0001. C, Cell counts of total cells and BrdU-positive cells in iRL and eRL (n = 4 embryos). Scale bar, 50 μm.