Figure 4.

Evaluation of Kitl^Sl-pan/Kitl^Sl-pan ovaries reveals defect in primary to secondary follicle transition associated with abnormal Foxo3 nuclear retention and stabilization. A) Kitl^Sl-pan ovaries are highly atrophic due to pleitropic defects in primordial follicle numbers and follicle maturation. B) H&E of tissue section showing predominant follicular morphology. Most follicles in Kitl^Sl-pan/Kitl^Sl-pan ovaries are arrested at the primary, not the primordial follicle stage, as evidenced by the cuboidal morphology and numbers of granulosa cells associated with each follicle (inset: normal primordial follicle from control ovary). C) Relative follicle counts in serially-sectioned ovaries (n=6 ovaries per genotype; error bars=s.e.m.). D) Foxo3 immunohistochemistry reveals nuclear retention of Foxo3 in Kitl^Sl-pan ovaries. Bars for B and D = 50 microns.