Figure 1. Impaired fertility and gonadal development in Faap20−/− mice.

(A) Faap20−/− mice exhibit reduced reproduction ability. Reproductive performance of 4 pairs of mice per group was followed over time. Faap20−/− (KO) mice were crossed with heterozygote (Het) mice. Heterozygotes (Het) and heterozygotes (Het) crossing was used as controls. (B) The testes of Faap20−/− mice are smaller than their wild type littermates. Photograph show testis from wild type (left) male and Faap20−/− littermate (right). (C) H&E stained testis and ovary sections from 2 month-old Faap20−/− and wild type littermates show developmental defect in gonads. All stages of spermatogenesis are seen in the wild-type adult testis. Faap20−/− testis show seminiferous tubules with scattered sertoli cells and decreased number of spermatocytes and spermatids. Many follicles with oocytes at various stages of development can be seen in the wild type ovary. The Faap20−/− ovary is smaller in comparison to the wild type ovary with reduced number of follicles (Magnification 50X, 100X, 200X). (D) β-Gal staining of testis and ovary sections from 2 month-old Faap20+/− mice show cell type specific expression of FAAP20. There was no specific staining in epithelial and sertoli cells, but strong blue staining was seen in the spermatocytes and spermatids (arrows) in testis. In ovary section, the β-Gal signal was detected only in the follicles area (arrow). (Magnification 100X, 400X).