Isolation and initial characterization of a vasa homolog in Cynops cyanurus

The vasa mRNA encodes a putative RNA helicase that belongs to the DEAD-box protein family. Vasa protein is a conserved germ cell marker ranging from fruit fly to human. In this study, we cloned the full-length vasa cDNA from the ovary of newt Cynops cyanurus and examined its expression in embryos and adult tissues. The predictive C. cyanurus Vasa protein sequence shares eight conserved regions with Vasa proteins from other vertebrates. The C. cyanurus vasa mRNA expression is restricted to testis and ovary. During oogenesis, vasa mRNA shows highest expression in the early stages of oocytes. However, it rapidly down-regulates during embryogenesis. These findings suggest that Vasa may be involved in early germ cell specification/initiation in C. cyanurus.