LncRNA AK015322 promotes proliferation of spermatogonial stem cell C18-4 by acting as a decoy for microRNA-19b-3p.

Long noncoding RNAs (lncRNAs) have been reported to play important roles in male reproduction. In our previous research, we studied the expression profile of lncRNAs in mouse male germ cells including spermatogonial stem cell, type A spermatogonia, pachytene spermatocyte, and round spermatid by microarray method, which showed that testis-enriched lncRNA AK015322 is highly expressed in spermatogonial stem cell. In this study, we found that AK015322 promotes proliferation of mouse spermatogonial stem cell line C18-4 in vitro. Furthermore, bioinformatic analysis, real-time PCR, and luciferase assay validated that AK015322 serves as a decoy of microRNA-19b-3p (miR-19b-3p), antagonizes its function, and attenuates the repression of its endogenous target transcriptional factor Ets-variant 5 (ETV5) which was a pivotal gene for spermatogonial stem cell self-renewal. Taken together, our results suggest that a variety of lncRNAs may regulate male reproduction through serving as competing-endogenous RNAs to modulate the function of germ cells.