Fig. 3: Impaired spermiogenesis in male Cep112-knockout mice.

a Wildtype (WT) mice (Cep112^+/+), heterozygous mice (Cep112^+/−), and Cep112-knockout mice (Cep112^−/−) were bred with WT counterparts to determine average litter sizes. Cep112^−/− male mice exhibited severely reduced fertility, with almost no offspring produced, while Cep112^+/− male mice remained fertile. In contrast, female reproductive function was unaffected in Cep112^−/− mice. n = 12 independent mice per sex per genotype, each mated with two WT counterparts. (Two-sided Student’s t test; error bars, mean ± SEM). The p values are indicated in the graphs. Source data are provided as a Source Data file. b Spermatogenic cell quantification using STA-PUT method: Cep112^−/− mice had significantly fewer round and elongating/elongated spermatids. n = 3 independent mice per genotype. (Two-sided Student’s t test; error bars, mean ± SEM). The p values are indicated in the graphs. Source data are provided as a Source Data file. c and d Histological analysis of testes and epididymides from Cep112^−/− mice. Hematoxylin and eosin (H&E) staining of testicular sections revealed degenerated spermatogenic cells in the lumen and disrupted cell-to-cell contacts within seminiferous tubules at different stages of spermatogenesis (c). Epididymal sections from Cep112^−/− mice showed significantly fewer spermatozoa compared to Cep112^+/+ (d) (Scale bar: 50 μm). Papanicolaou staining (e) and SEM analysis (f) showed that Cep112^−/− mice had abnormal sperm morphologies, including absent, short, bent and coiled flagella, and defective heads were also visible. SEM analysis also showed abnormal annulus and disorganized midpiece-principal piece junctions in Cep112^−/− spermatozoa. Magnified areas are indicated by magenta dashed rectangles (Scale bar: 5 μm). g TEM cross-sectional analysis of Cep112^−/− mouse sperm flagella revealed various ultrastructural defects, including mitochondrial sheath (MS) abnormalities, disordered and absent outer dense fibers (ODFs), missing microtubules, disorganized microtubule doublets (MTDs), and absence of central pairs (CPs) (Scale bar: 500 nm). h TEM analysis of spermiogenesis in Cep112^−/− mice showed impaired development of the connecting piece and defective conjunctions between sperm head and tail at different developmental stages (Scale bar: 500 nm). Experiments were repeated three times independently with similar results; representative images are shown in c–h.