Figure 7.

The number and survival of proliferative cell is reduced in hair follicles of the skin of adult Sos2 KO mice. (A) Representative confocal images of dorsal skin sections of WT and Sos2 KO adult mice immunolabeled for K5 (red) and BrdU (green) and counterstained with DAPI (blue). Scale bar: 50 μm. (B) Graph illustrates quantitation of number of hair follicle BrdU⁺ cells per 40× field. ** p < 0.01 vs. WT. (C) Representative confocal images of dorsal skin sections of WT and Sos2 KO adult mice from label-retaining experiments (see Materials and Methods) immunolabeled for BrdU (green) and counterstained with DAPI (blue). (D) Graph illustrates quantitation of number of survival hair follicle BrdU⁺ cells per 40× field. Arrowheads show proliferative cells. Scale bar: 25 μm. Data are expressed as means ± the SD. n = 3/genotype. * p < 0.05 vs. WT. (E) Representative flow cytometry scatter plots showing the different epidermal populations according to CD34 and integrin α6 expression in the skin of WT and Sos2 KO neonate mice. The gate used for the isolation of basal bulge epidermal stem cell population is depicted with a square. (F) The graph illustrates the quantitation of the abundance of the CD34⁺/integrin α6⁺ pools in the skin of WT and Sos2 KO adult mice. * p < 0.05 vs. WT; n = 4/genotype. (G) Western blot analysis shows Sos2 protein expression in dorsal skin from adult (2-month-old) and neonate WT mice. (H) Bar plot represent average of Sos2 protein expression in WT dorsal skin of adult and neonate mice. Data expressed as normalized ratios of Sos2 and tubulin protein expression. Data are expressed as means ± the SD. n = 3/group. Scale bars: 25 μm. * p < 0.05 vs. adult group.