MicroRNA-26b promotes transition from Kit^- to Kit⁺ mouse spermatogonia

During spermatogenesis, a group of undifferentiated spermatogonia undergoes an essential transition to a differentiating stage, which involves gain of Kit receptor. In the current study, we showed that a small non-coding RNA, miRNA-26b could induce transition from Kit^- to Kit⁺ and inhibit proliferation of spermatogonia. A key transcriptional factor for undifferentiated spermatogonia, Plzf, was proven as a direct target of miR-26b. When undifferentiated spermatogonia were treated with Retinoic acid (RA), miR-26b was increased, further promoting RA-induced differentiation of spermatogonia. In addition, miR-26b could repress 5-hydroxymethylcytosine (5hmC) via repression of Tet3 in spermatogonia. These findings demonstrate that miR-26b might play a role in promoting the transition from Kit^- to Kit⁺ SSCs.