PSMC3 is required for spermatogonia niche establishment in mouse spermatogenesis

Abstract Males produce millions of spermatozoa each day, which are originated from spermatogonia. Spermatogonia niche establishment and maintenance and the subsequent haploidization of spermatocytes in meiosis are hallmarks of this process. The function of the individual players and coordinated mechanisms regulating different stages of gametogenesis in mammals are not well understood. In this work we focused on the role of PSMC3 in mouse gametogenesis. We observed that Psmc3 is highly expressed in mouse testis, and it is widely expressed in different stages of gamete formation. Conditional deletion of Psmc3 results in both male and female impairment of gonad development at early pre-meiotic stages, but has no apparent effect on meiosis progression. This is likely a consequence of abnormal spermatogonia niche establishment and/or maintenance, revealed by a massive loss of undifferentiated spermatogonia. Our work defines a fundamental role of PSMC3 functions in spermatogenesis during spermatogonia development with direct implications in fertility.