title: Targeting the pseudorabies virus DNA polymerase processivity factor UL42 by RNA interference efficiently inhibits viral replication.
abstract: RNA interference (RNAi) is a conserved gene-silencing mechanism in which small interfering RNAs (siRNAs) induce the sequence-specific degradation of homologous RNAs. It has been shown to be a novel and effective antiviral therapy against a wide range of viruses. The pseudorabies virus (PRV) processivity factor UL42 can enhance the catalytic activity of the DNA polymerase and is essential for viral replication, thus it may represent a potential drug target of antiviral therapy against PRV infection. Here, we synthesized three siRNAs (siR-386, siR-517, and siR-849) directed against UL42 and determined their antiviral activities in cell culture. We first examined the kinetics of UL42 expression and found it was expressed with early kinetics during PRV replication. We verified that siR-386, siR-517, and siR-849 efficiently inhibited UL42 expression in an in vitro transfection system, thereby validating their inhibitory effects. Furthermore, we confirmed that these three siRNAs induced potent inhibitory effects on UL42 expression after PRV infection, comparable to the positive control siRNA, siR-1046, directed against the PRV DNA polymerase, the UL30 gene product, which is essential for virus replication. In addition, PRV replication was markedly reduced upon downregulation of UL42 expression. These results indicate that UL42-targeted RNAi efficiently inhibits target gene expression and impairs viral replication. This study provides a new clue for the design of an intervention strategy against herpesviruses by targeting their processivity factors.
authors.affiliation: Division of Swine Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, 427 Maduan Street, Nangang District, Harbin 150001, China.
authors.forename: Yi-Ping
authors.initials: YP
authors.lastname: Wang
authors.affiliation: Division of Swine Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, 427 Maduan Street, Nangang District, Harbin 150001, China.
authors.forename: Li-Ping
authors.initials: LP
authors.lastname: Huang
authors.affiliation: Division of Swine Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, 427 Maduan Street, Nangang District, Harbin 150001, China.
authors.forename: Wen-Juan
authors.initials: WJ
authors.lastname: Du
authors.affiliation: Division of Swine Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, 427 Maduan Street, Nangang District, Harbin 150001, China.
authors.forename: Yan-Wu
authors.initials: YW
authors.lastname: Wei
authors.affiliation: Division of Swine Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, 427 Maduan Street, Nangang District, Harbin 150001, China.
authors.forename: Hong-Li
authors.initials: HL
authors.lastname: Wu
authors.affiliation: Division of Swine Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, 427 Maduan Street, Nangang District, Harbin 150001, China.
authors.forename: Li
authors.initials: L
authors.lastname: Feng
authors.affiliation: Division of Swine Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, 427 Maduan Street, Nangang District, Harbin 150001, China. Electronic address: lcm@hvri.ac.cn.
authors.forename: Chang-Ming
authors.initials: CM
authors.lastname: Liu
mesh_terms: D000818:Animals; D002460:Cell Line; D002478:Cells, Cultured; D004259:DNA-Directed DNA Polymerase / Q000235:genetics*; D005090:Exodeoxyribonucleases / Q000235:genetics*; D015967:Gene Expression Regulation, Viral; D011558:Herpesvirus 1, Suid / Q000502:physiology*; D006801:Humans; D034622:RNA Interference; D012333:RNA, Messenger / Q000737:chemistry / Q000235:genetics; D034741:RNA, Small Interfering / Q000235:genetics*; D012367:RNA, Viral; D014764:Viral Proteins / Q000235:genetics*; D014779:Virus Replication / Q000235:genetics*
chemical_list: D012333:RNA, Messenger; D034741:RNA, Small Interfering; D012367:RNA, Viral; D014764:Viral Proteins; D004259:DNA-Directed DNA Polymerase; D005090:Exodeoxyribonucleases; C043417:DNA polymerase, Simplexvirus
keywords: DNA polymerase; Processivity factor; Pseudorabies virus; RNA interference; UL42