Feedback regulation of Ran gene expression by Ran protein.

Ran, an abundant GTPase that is highly conserved in eukaryotes from yeast to human, has been implicated in many aspects of nuclear structure and function. Recently it is revealed that the Ran GTPase can regulate the hemocytic phagocytosis of shrimp by interaction with myosin. However the regulation of Ran gene expression remains unknown. In this study, the promoter of shrimp Ran gene was identified which contained a typical TATA box. The results showed that the shrimp Ran protein was bound with the Ran promoter in Drosophila S2 cells. Based on luciferase assays, our study indicated that the transcription of Ran gene could be regulated by the interaction between the Ran promoter and the Ran protein, suggesting the existence of a feedback regulation in Ran gene expression. Therefore our study presented a novel finding on the feedback regulation of gene transcription.