The synthesis and storage of mRNAs prior to their translation is a necessity during spermatogenesis as global transcription ceases several days prior to the completion of spermatid differentiation. Post–transcriptional control can be mediated by sequences in the 5′ and 3′ untranslated regions of mRNAs, and in some cases separate elements may regulate translational repression and translational activation. Translational repression is essential for spermatid differentiation as premature translation can lead to an arrest in spermatid differentiation and cause dominant male sterility.