Spermatogenesis is closely regulated by non-coding RNA, including: (a) Selfrenewal of undifferentiated spermatogonia (undiff. Spga): miR-21 [25], miR- 34c [25]; (b) Differentiation of spermatogonia (Diff. Spga): Mirc1 [27], Mirc3 [27], Mirlet7 [71]; (c) Differentiation to spermatocytes (Spcy): miR-15a [29], miR-184 [72]; (d) Meiotic division of spermatocytes to spermatids (Sptd): miR- 18 [24], miR-34b, miR-34c [28], miR-184 [72], miR-383, mir-449, miR-469 [31]; (e) Differentiation of spermatid to form spermatozoa: miR-34c [28], miR-469 [31].
Figure 1: Validated microRNA candidates involved in spermatogenesis