Conditional deletion of Sox2 by way of RVV transduction produces smaller clones that contain fewer neurons than control.

(A) Cartoon illustration of retroviral construct used for transduction with Cre recombinase. (B, C) Representative clones from whole mount tissue harvested 3 weeks after infection. (B) X-gal staining demonstrates the typical clone size from control R26^{fl(stop)-LacZ} indicator mice transduced with Cre. (C) GFP fluorescence expressed from the RRV, demonstrates the typical clone size from Sox2^flox/flox transduced mice. (D) Representative histological section stained to detect β-galactosidase activity within a clone following Cre-transduction in a R26^{fl(stop)-LacZ} control mouse; note the large numbers of neurons, which are situated broadly along the middle of the epithelium. (E-G) Representative sections from Cre/GFP-expressing clones in Sox2^flox/flox mice that have been immunostained to characterize clonal composition. Dashed lines mark the basal lamina. (H) The range in the number of cells/clone is depicted in the form of a box-and-whiskers scatter plot, and the horizontal black line within the box indicates the median clone size, where the median values were 19 and 3, respectively. The distributions are significantly different (Mann-Whitney-U test, *** p < 0.001). (I) The proportion of infected clones containing neurons or not is depicted in the form of a stacked bar graph, gray and black respectively. The proportions are significantly different between wildtype and knockout (Z test, *** p < 0.001) (J) Compositional analysis plotting the number of the different types of cells in each clone, by a box-and-whiskers scatter plot; median clone size is indicated with a black line. Median values for control vs. knockout for basal, OSN, Sus, and D/G are 0 vs. 1, 2 vs. 0, 3 vs. 1, and 0 vs. 0, respectively. Note that both the number of neurons and the number of Sus cells are significantly reduced by Cre-mediated recombination in floxed Sox2 mice as shown by Dunn’s method for pairwise comparisons (indicated by the horizontal lines, * p < 0.05). Scale bar in (C) corresponds to 50 μm and also applies to B, scale bars in D-G correspond to 10 μm.