Temporal Expression and Steroidal Regulation of piRNA Pathway Genes (Mael, Piwi, Vasa) During Silurana (Xenopus) Tropicalis Embryogenesis and Early Larval Development

The study investigated the role of the piRNA pathway in the regulation of sex steroid hormones during the embryogenesis and early larval development of Silurana (Xenopus) tropicalis. Researchers focused on the expression patterns of three piRNA pathway genes: mael, piwi, and vasa. These genes showed high expression at early developmental stages, which decreased significantly later, suggesting their active involvement in early embryogenesis. The study also examined the effects of sex steroid biosynthesis inhibitors, fadrozole and finasteride, on these genes. Both inhibitors increased the expression of mael and vasa during the larval stage, when their expression is typically low, indicating that the piRNA pathway might be a common mechanism through which sex steroid hormones influence gonadal sex differentiation.