Molecular Characterization of a Male-specific SoxE Gene in the Swimming Crab, Portunus trituberculatus, and Transcriptional Interaction with Insulin-like Androgenic Gland Hormone

The Sry-related HMG-box (Sox) family is a group of transcriptional regulators that play a critical role in many important developmental processes in both vertebrates and invertebrates. In aquatic animals, the function of Sox genes on sexual development has been gained particular attentions. The present study reported the molecular characterization of a Sox member (PtSoxE) in the swimming crab, Portunus trituberculatus, and tissue distribution analysis showed it was male-specific. Since the most highly expression of PtSoxE was found in the androgenic gland (AG), its relation to the insulin-like androgenic gland hormone (IAG) was further investigated. The PtSoxE siRNA caused a significant decrease in IAG expression in both AG and testis, whereas PtSoxE expression could be induced by treating with AG homogenate and rIAG. The result suggested a transcriptional interaction between PtSoxE and IAG. In addition, PtSoxE expression showed a closely positive correlation with several reported spermatogenesis-related genes, suggesting its involvement in testicular development of P. trituberculatus.