The protein encoded by a murine male germ cell-specific transcript is a putative ATP-dependent RNA helicase

The muring PL10 cDNA corresponds to a transcript expressed only in the male germ line. Its expression is developmentally regulated, with high levels of transcripts being present during the meiotic and haploid stages of spermatogenesis. The deduced protein is shown to be highly homologous to the murine translation initiation factor eIF-4A and to other proteins that are also homologous to eIF-4A, including the Drosophila protein vasa. By consensus sequence conservation and comparison of secondary structure predictions, putative mononucleotide binding and DNA RNA binding domains are proposed to be shared by all these proteins. Taken together, these results suggest a helicase function for PL10 protein similar to that of eIF-4A and suggest its possible role in a key step of the spermatogenic process. The possible significance of the similarity between the PL10 protein and the protein product of the maternal effect gene vasa is also discussed.