Effect Of DHX15 On The Replication Of HBV And Its Mechanism

Objective: To screen DDX family for genes that affect the transcription activity of HBV core promoter or the enhancers,and investigate the relationship between DHX15 and HBV replication in vitro.Methods:1.The DDX family genes were cloned into the expression plasmid PCH9 respectively.2.The report plasmid pcore-Rluc was constructed which driven by the HBV enhancer and core promoter.3.Each DEx D/H-box expression plasmids and pcore-Rluc were used to transfect HepG2 cells,and the DDX family members that affected the Rluc luciferase activity were screened.4.HepG2 cells were transiently co-transfected with DHX15 expression plasmid and HBV1.3.5.The effects of DHX15 overexpression on the HBV DNA replication and the HBV RNA transcription were tested by using Southern blot and Northern blot respectively.6.HBV core promoter truncated mutants were constructed to dissectthe sequence might interacting with DHX15.Results:1.Thirty DEx D/h-box family genes were successfully cloned.2.DHX15 significantly influenced the activity of HBV core promoter(P=0.042).3.Compared with the control,overexpression of DHX15 promoted the replication of HBV DNA and increased the transcription level of HBV RNA in Hep G2 cells.4.Both of the 2 HBV enhancers seem to be partially responsible for the upregulation effect of DHX15 on the activity of HBV core promoter.(t=8.292,P=0.0012;t=5.215,P=0.0064).Conclusion: Overexpression of DHX15 promotes HBV replication in HepG2 cells by affecting the activity of HBV enhancers.