Fig. 5: Mcph1-ΔBR1 mice show developmental block in reproductive organs.

A Macroscopic view of testes of control and Mcph1-ΔBR1 mice. Testis size is strongly reduced in Mcph1-ΔBR1 mice compared to controls (Ctr). B Ratio of paired testis weight to body weight (TW/BW) is significantly lower in Mcph1-ΔBR1 mice compared to controls. The number of mice analysed is indicated within the bar. C Representative pictures of H&E stained testis sections demonstrate a strong degeneration of the testicular germinal epithelium in Mcph1-ΔBR1 mice with lack of post-meiotic cells. Note that mutant testis tubules contain either few or lack of spermatocytes (sc) and vacuolised lumens (lu). D Quantitative histological analyses of H&E stained testis sections reveal significantly smaller diameter of seminiferous tubules and a strong vacuolisation of the germinal epithelium in Mcph1-ΔBR1 mice. Each circle represents one Ctr mouse and each diamond one Mcph1-ΔBR1 mouse. Per mouse, 30 circular tubular cross-sections were analysed to determine the diameter, and a minimum of 70 tubular cross-sections per mouse have been evaluated for presence or absence of vacuoles (va). The number of mice analysed is indicated within the bar and the number of analysed (circular) tubular cross-sections is indicated under the genotype in parentheses. E Representative pictures of immunostaining of testis sections by the indicated antibodies. DEAD box helicase 4 (Ddx4) germ cell marker staining detects residual germ cells (red arrows) in mutant testes. Lin-28 homologue A (Lin28) is expressed by spermatogonial stem cells and progenitors (green arrows). SRY-box 9 (Sox9) marker protein is expressed normally in Sertoli cells (blue arrows) of mutants and controls. Intense brown colour indicates positive marker staining, blue colour depicts hematoxylin counterstaining. Quantification of marker proteins is shown on the right panel of respective immunostaining. The number of mice analysed is indicated within the bar. The number of tubuli analysed is indicated under the genotype in parentheses. All experiments have been performed on testicular cross-sections of adult mice (9.5–12 months old). Bars represent Means ± SEM of a minimum of 3 determinations. Statistical analysis was performed by Student’s t-test. **p < 0.01, ***p < 0.001.