A translation regulator that drives spermatogonial stem cell formation.

Background: Spermatogonial stem cells (SSCs) are essential for adult spermatogenesis. Themolecular mechanisms driving SSC generation are poorly understood.

Objectives: Zou et al. reported that the precursor cells that give rise to SSCs-prospermatogonia (ProSG) require the RNA-binding protein, DDX20, in orderto undergo the obligatory proliferative re-activation step that proceeds SSC formation.

Materials and methods: Literature search.

Results and conclusion: We summarize the authors' discovery that the RNA-binding protein, DDX20, iscritical for driving the proliferative re-activation of ProSG, a key step that proceeds SSC generation in vivo. They provide evidence that DDX20 performs this role through its ability to promote the translation of mRNAs encoding proteins known to be essential for cell-cycle and spermatogonial homeostasis. It remains to be determined whether this role is conserved inhumans. It will also be interesting to elucidate whether other post-transcriptional regulators also have roles in early germ cell development. More broadly, it will be fascinating to determine whether post-transcriptional regulators workin concert with transcriptional regulators to drive germ-cell development.