Cyclin T2: a novel miR-15a target gene involved in early spermatogenesis.

MicroRNAs (miRNAs) are posttranscriptional modulators of gene expression that play important roles in various biological processes. Spermatogenesis is a highly regulated process in which diploid spermatogonia eventually differentiate into haploid spermatozoa. In this study, we identified four differentially expressed miRNAs between two premeiotic male germ cells, made predictions about their putative targets, and confirmed cyclin T2 (Ccnt2) as a direct target of miR-15a. We also report that miR-15a inhibited muscle differentiation at least in part by targeting Ccnt2, which represents a novel interaction. Subsequently, miR-15a and Ccnt2 were profiled in developing mice testes to observe their inverse correlations in the postnatal 3-week period to understand their roles in spermatogenesis.