CircCamsap1 is dispensable for male fertility in mice.

ABSTRACT

Background: Circular RNAs (circRNAs) are a large class of RNAs present in mammals. Among these, circCamsap1 is a well-acknowledged circRNA with significant implications, particularly in the development and progression of diverse tumors. However, the potential consequences of circCamsap1 depletion in vivo on male reproduction are yet to be thoroughly investigated. Methods: The presence of circCamsap1 in the mouse testes was confirmed, and gene expression analysis was performed using reverse transcription quantitative polymerase chain reaction. CircCamsap1 knockout mice were generated utilizing the CRISPR/Cas9 system. Phenotypic analysis of both the testes and epididymis was conducted using histological and immunofluorescence staining. Additionally, fertility and sperm motility were assessed. Results: Here, we successfully established a circCamsap1 knockout mouse model without affecting the expression of parental gene. Surprisingly, male mice lacking circCamsap1 (circCamsap1-/-) exhibited normal fertility, with no discernible differences in testicular and epididymal histology, spermatogenesis, sperm counts or sperm motility compared to circCamsap1+/+ mice. These findings suggest that circCamsap1 may not play an essential role in physiological spermatogenesis. Nonetheless, this result also underscores the complexity of circRNA function in male reproductive biology. Therefore, further research is necessary to elucidate the precise roles of other circRNAs in regulating male fertility.