Abstract
The RNA binding protein Dazl is essential for gametogenesis, but its direct in vivo functions, RNA targets, and the molecular basis for germ cell loss in DAZL KO mice are unknown. Here, we generated transcriptome-wide maps of Dazl-RNA interactions in adult and juvenile mouse testes. In parallel, we used transgenic mice and fluorescence activated cell sorting to isolate DAZL knockout germ cells and identify mRNAs sensitive to Dazl deletion. Integrative analyses reveal that Dazl functions as a master regulator of germ cell survival by post-transcriptionally enhancing a vast network of genes necessary for cell cycle regulation and spermatogenesis. Strikingly, Dazl displays a strong positional bias for binding near polyA tails and multimerizes on a subset of its targets. These results reveal a mechanism for Dazl recruitment to its RNA targets and delineate a Dazl-dependent mRNA regulatory program essential for postnatal mammalian germ cell survival.