<p>We hypothesize that in early-step spermatids, p37 mainly binds to the RTS in the <i>Prm2</i> mRNA 3′UTR, leading to a translationally repressed configuration of the <i>Prm2</i> mRNA. In the cytoplasm of later step spermatids, p37 is released from the RTS through yet unknown mechanisms, and p42 is able to interact with the RTS and with the 5′ mRNA cap binding complex. This exchange may be regulated through cooperative association with hnRNP A2. We propose that the p37–p42 relay contributes to the temporal regulation of the <i>Prm2</i> mRNA translation during spermatogenesis.</p
