Fig. 2.

Ectopic cell division in the absence of p27. a Double immunofluorescence for BrdU and phospho-histone H3 (pH3) in the wild-type (WT) and p27 knockout (KO) retinas at different postnatal ages. The central retinal regions are shown. BrdU+ and pH3+ cells are observed only in the KO retinas at P6 and thereafter. Note pH3+ cells are ectopically positioned in the inner nuclear layer (INL) at P9 (arrows). GCL, ganglion cell layer; NBL, neuroblastic layer; ONL, outer nuclear layer. Dotted lines indicate the border between the ONL and INL. Scale bar = 20 μm. b Quantification of BrdU+ and pH3+ cells in the KO retinas. Each bar represents the mean ± SEM (n = 3 per age)