Expression and its functional study on hypertension-related gene FXYD5 in smooth muscle cell by RNA interference

Objective: To explore the function of FXYD5 gene in the pathogenesis of hypertension by specifically silencing the FXYD5 expression in vascular smooth muscle cells(VSMCs). Methods: Design and synthesize four siRNAs targeting FXYD5(siRNA-1, siRNA-2, siRNA-3, siRNA-4); transfect the rat thoracic artic smooth muscle cell line(CRL-1444) by using four synthesized siRNA and siRNA with nonspecific coding sequence(siRNA-con) as control group; Estimated the transfection efficiency through the laser scanning confocal microscope and analyze the mRNA expression of FXYD5 by real-time PCR and further analyze the cellular proliferation, mobility as well as Na+-K+-ATPase activity of CRL-1444 after specifically silencing the FXYD5expression. Results: The results of real-time PCR showed FXYD5 mRNA was suppressed by 86.71%(P0.01)and 90.17%(P0.01) respectively by siRNA-1 and siRNA-2, while no distinctive change was found in siRNAcon treated VSMCs(P0.05); The cellular proliferation among four groups was similar(P0.05); but the mobility of siRNA-1 and siRNA-2 transfected groups was weaker than that in siRNA-con transfected group and blank control group(P0.01); the activity of cell membrane Na+-K+-ATPase in siRNA-1 and siRNA-2 transfected groups was lower than that in siRNA-con transfected group and blank control group(P0.05).Conclusion: RNA interference technology can selectively silence FXYD5 gene expression in rat aortic smooth muscle cells; and inhibit the migration of smooth muscle cells and cell membrane Na+-K+-ATPase activity. The result reveals the potential functions of FXYD5 in the pathogenesis of hypertension and leads to the inference that FXYD5 may be a new associative gene of hypertension.