Fig. 1: The depletion of CARF in male mice leads to SCO syndrome and impaired fertility.

a Comparison of male fertility of WT control and CARF^−/− mice (n = 5) at 8–16 weeks of age. Each dot in the graphs represents an individual litter. Bar graphs represent means ± SEM. Statistical analysis was performed by two-tailed t-test, ***P < 0.001. b Gross morphology of representative testes, epididymides and seminal vesicles from 16-week-old WT control (left) and CARF^−/− mice (right). c Average testes weight of WT control mice (n = 11) and CARF^−/− (n = 8) at 8–16 weeks of age. Each dot in the graphs represents an individual mouse. Bar graphs represent means ± SEM. Statistical analysis was performed by two-tailed t-test, **P < 0.01. d H&E staining of representative testis sections from 16-week-old WT control and CARF^−/− mice (Scale bars, 200 μm). The boxed area is magnified on the right side. The white asterisk indicates an SCO seminiferous tubule. Dot graph shows the ratios of SCO seminiferous tubules in the testis sections from 8- to 16-week-old WT control and CARF^−/− mice (mice, n = 6; sections of one mouse, n > 5). Each dot in the graphs represents an individual mouse. Bar graphs represent means ± SEM. Statistical analysis was performed by two-tailed t-test, ***P < 0.001. e Immunostaining for undifferentiated spermatogonia (including SSCs) marker PLZF (red) in testis sections from 16-week-old WT control and CARF^−/− mice, with co-staining for DAPI (blue) (Scale bars, 200 μm). The boxed area is magnified on the right side. Dot graph shows the ratios between PZLF⁺ undifferentiated spermatogonia and Sertoli cells per seminiferous tubule in testis sections from 8- to 16-week-old WT control and CARF^−/− mice (mice, n = 5; tubules of one mouse, n ≥ 6). Each dot in the graphs represents an individual mouse. Bar graphs represent means ± SEM. Statistical analysis was performed by two-tailed t-test, **P < 0.01. f Cross-sectional images of PLZF (red) immunostaining, BrdU (green) immunostaining and DAPI (blue) staining of testis sections from 16-week-old WT control and CARF^−/− mice (Scale bars, 50 μm). Dot graph shows the percentage of BrdU⁺&PLZF⁺ cells in total PLZF⁺ cells of testis sections from 8- to 16-week-old WT control and CARF^−/− mice (mice, n = 8; tubules of one mouse, n ≥ 6). Each dot in the graphs represents an individual mouse. Bar graphs represent means ± SEM. Statistical analysis was performed by two-tailed t-test, *P < 0.05.