Spsb3 is not essential for spermatogenesis and male fertility in mice

Spermatogenesis, the process by which male germ cells develop into mature spermatozoa, is a complex and highly regulated phenomenon crucial for male fertility. Various molecular pathways, including ubiquitination, play critical roles in this process. Ubiquitination regulates multiple stages of spermatogenesis by controlling cell remodeling and protein metabolism. SplA/ryanodine receptor domain and SOCS box containing 3 (SPSB3), a SOCS box protein, interacts with ElonginC/B and recruits Cullin5 to form the ECS E3 ligase complex, which is involved in cell development, proliferation, stress response, and apoptosis. However, the specific role of SPSB3 in spermatogenesis and male reproduction remains poorly understood.

The distribution and expression of Spsb3 were analyzed using bioinformatics approaches. Spsb3-knockout (KO, Spsb3 ) mice were generated using CRISPR/Cas9 gene editing. Sperm quality was assessed using a computer assisted sperm analysis (CASA) system. Histological and immunostaining analyses were performed to evaluate the effects of Spsb3 deletion on mouse testicular structure. Apoptotic cells were detected using terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL).

Our findings indicate that Spsb3 is a testis-enriched gene in mice. However, no significant differences were observed in sperm quality, fertility, or testis histology between Spsb3 ^-/- and wild-type (WT) adult mice.

This is the first functional study of Spsb3 in mammalian reproduction. Despite its evolutionary conservation and high testicular expression, Spsb3 is not essential for mouse spermatogenesis under physiological conditions.