Title Preliminary Study Of Mouse Testis-specific MiR-471 Expression And Function

microRNA (miRNA) is a family of～22nt short single-strand RNAs, which exists in various organisms and plays crucial roles in regulating various biological processes. Series of large-scale high-throughput library screening and microarray studies have found and characterized a large reservoir of miRNAs. However, the definitive functions of which are poorly understood, especially for those related to male germ cell development. In this study we investigated the functions of a mouse testis-specific miRNA, miR-471. Expression profiling revealed a temporal expression pattern of miR-471 in neonatal and adult mouse testes. We constructed an expression vector of miR-471 by PCR cloning, and validated the overexpression system in 3T3 cell lines. We found that stable expression of miR-471 in 3T3 cell lines significantly enhance cell proliferation. Furthermore, using previously established mouse spermatogonial stem cell (SSC) in vitro model, we observed that the proliferation-promoting function is also present when miR-471 overexpressed in mouse SSCs cultured in vitro. These proof-of-principle results provide fundamental tools and essential clue for further functional studies on miR-471 as well as other mouse testis-specific miRNAs.