The deubiquitinating gene Usp29 is dispensable for fertility in male mice.

The balanced actions between ubiquitination and deubiquitination precisely control the levels of various proteins vital for spermatogenesis. Ubiquitin-specific processing proteases (USPs) are the largest family of deubiquitinatingenzymes(DUBs), containing more than 50 members. So far, the functions of only a few USPs in male fertility have been studied, the roles of the majority are yet unknown. The present study aimed to explore the function of Usp29 (ubiquitin-specific protease 29) in male fertility. We found that Usp29 showed predominant expression in mouse testis, and its mRNA expression started to increase at 14 days postpartum (dpp), with a peak at 28 and 35 dpp. Using CRISPR/Cas9 technology, we generated Usp29 knockout mice (Usp29). Usp29 mice exhibited no overt developmental anomalies. Further examination revealed that Usp29 mice had normal fertility and showed no detectable difference in the testis/body weight ratio, testicular and epididymal histology as well as epididymal sperm count from the wild-type littermates. Moreover, Usp29 is not a pseudogene in mice. Taken together, our study first reported that though Usp29 is predominantly expressed in the testis, it is not essential for male fertility in mice.