Mir-103-3p Down Regulates The Expression Of ERG Gene

Background and Objective: Sudden Cardiac Death is seriously harmful to the health of all human beings.In our country,544 thousand people die each year from SCD.90% SCD is associated with malignant arrhythmias such as ventricular fibrillation.hERG(Human ether-a-gogo-related gene)encodes the ? subunit of Ikr(rapidly activated delayed rectifier potassium currents)which plays an important role in the 3 phase of the action potential.When function of the current disorders,QT interval will prolong,causing arrhythmia.A large number of studies have indicated that miRNA is related to the occurrence and development of arrhythmia.In our prophase research,we find miRNAs which are related to hERG by bioinformatics websiteand verify the miRNAs by the dual luciferase gene report method.We find that has-miR-103a-1 is related to the expression of hERG gene.We also find miR-103a-1 down regulates expression of the hERG gene in HEK-293 cells by Blot Western,real-time fluorescence quantitative PCR,laser confocal and patch clamp.HEK-293 cell is commonly used in the study of foreign genes because it rarely expresses in the receptor and is easy to be transfected.But HEK-293 cells can not simulate the human ventricular myocardial cells,and human ventricular myocardial cells are not easy to be obtained,so it is necessary to further verify the regulation mechanism of miR-103a-1 on ERG gene in the animal ventricular myocytes.Methods: H9c2 rat cardiac myoblasts are transiently transfected with pcDNA3-hERG via Lipofectamine 2000 for 24 h.The rno-miR-103-3p agomir,rno-miR-103-3p agomir nc,rnomiR-103-3p antagomir or rno-miR-103-3p antagomirnc was transfected into H9C2 cells.After 48 h of transient transfection,the Expression of ERG mRNA was quantified by real-time RT-PCR.Protein levels of ERG were measured by Western blot analysis.Immunocytochemistry examinethe cells ERG protein expression under an Eclipse 80 i fluorescence microscope.Neonatal rat cardiomyocytes are transfected with AMO-103 which is the ason of miR-103.After 96 h,we detect protein of ERG gene?Results: We treated H9C2 cells with rno-miR-103-3p agomir nc or rno-miR-103-3p agomir for 48 h.: the Expression of ERG mRNA is no significant difference between them;the ERG protein level of gene becames lower than the former.We treated H9C2 cells withrnomiR-103-3p antagomir nc or rno-miR-103-3p antagomir for 48 h:the Expression of ERG mRNA is no significant difference between them;the ERG protein level of gene became higher than the former.After transfection of AMO-103 into neonatal rat cardiomyocytes,the level of ERG protein decreased.Conclusion In brief,our study revealed that rno-miR-103-3p is involved in ERG deficiency at protein levels.This discovery may provide a novel mechanism of ERG channel deficiency,and AMO-103-3p may become a potential therapeutic target.