Fig. 2: The deletion of Gss in germ cells caused abnormal spermatogenesis.

A The H&E staining of testis and caudal epididymis from 2-month-old S8/Control and S8/Gss^−/− mice. Scar bar = 50 μm. B Histological structures of testis and caudal epididymis in 8-month-old S8/Control and S8/Gss^−/− mice. The images in the far-right column are the magnified view of the seminiferous tubules labeled with an asterisk. Scar bars = 50 μm. C The diameters of the seminiferous tubules were measured in 8-month S8/Control and S8/Gss^−/− mice. ***P < 0.001, 240 seminiferous tubules were counted for each group. D The immunofluorescence staining of DDX4 in testes from 8-month-old S8/Control and S8/Gss^−/− mice. Scar bar = 50 μm. E Germ cell quantification in the single seminiferous tubule of 8-month-old mice. ***P < 0.001; n = 6 (biologically independent animals); 10 tubules were tested for each mouse. F, G TUNEL staining and the percentage of positive cells in the testicular sections from 8-month-old S8/Control and S8/Gss^−/− mice. Scar bar = 50 μm. ***P < 0.001; n = 4 (biologically independent animals); more than 10 apoptotic tubules were counted for each mouse. H The H&E staining of the seminiferous tubules at different stages. Scar bar = 20 μm. I The count of spermatogenic cells in 8-month-old S8/Control and S8/Gss^−/− mice. ***P < 0.001; n = 6 (biologically independent testes from six different animals); more than 65 tubules were counted for spermatocytes and round spermatids, and 45 tubules at stages IX–X were used to analyze elongated sperms.