Fig. 1: TRF1 is required for spermatogenesis

a The Stra8-Trf1^−/− mice testes were smaller than those of the Trf1^Flox/Flox and Stra8-Trf1^+/− mice (10-week-old, and the same to the below). b Quantification of testis weight of the Trf1^Flox/Flox and Stra8-Trf1^+/− mice. Testis weight: Trf1^Flox/Flox (grey bar, 151.20 ± 1.42 mg), Stra8-Trf1^+/− (black bar, 148.40 ± 1.96 mg), Stra8-Trf1^−/− (white bar, 27.40 ± 1.69 mg). Data are presented as mean ± SEM. ***P < 0.001. c The TRF1 protein levels were reduced in the testes of the Stra8-Trf1^−/− mice. Histone H2A was used as the loading control. d PAS-hematoxylin analysis of the seminiferous tubules of Trf1^Flox/Flox and Stra8-Trf1^−/− mice. Arrows indicate apoptotic cells. e The diameter of the seminiferous tubules in Stra8-Trf1^−/− mice was smaller than that of the Trf1^Flox/Flox mice. Trf1^Flox/Flox (gray bar, 195.50 ± 4.49 μm), Stra8-Trf1^−/− (white bar, 102.40 ± 3.62 μm). Data are presented as mean ± SEM. ***P < 0.001. f Histological analysis of the caudal epididymides from 10-week-old Trf1^Flox/Flox and Stra8-Trf1^−/− mice. g The total number of sperm in the cauda epididymis was significantly decreased in the Stra8-Trf1^−/− mice. Trf1^Flox/Flox (grey bar, 19.03 ± 1.22 × 10⁶), Stra8-Trf1^−/− (white bar, 0.06 ± 0.11 × 10⁶). Data are presented as mean ± SEM. **P < 0.01.