title: In vitro inhibition of transmissible gastroenteritis coronavirus replication in swine testicular cells by short hairpin RNAs targeting the ORF 7 gene.
abstract: BACKGROUND
  Transmissible gastroenteritis (TGE) is a highly contagious viral disease of swine, characterized by severe vomiting, diarrhea, and high mortality. Currently, the vaccines for it are only partially effective and no specific drug is available for treatment of TGE virus (TGEV) infection. RNA interference has been confirmed as a new approach for controlling viral infections. In this study, the inhibitory effect of short hairpin RNAs (shRNAs) targeting the ORF 7 gene of TGEV on virus replication was examined.
  
  
  RESULTS
  Four theoretically effective sequences of TGEV ORF 7 gene were designed and selected for construction of shRNA expression plasmids. In the reporter assays, three of four shRNA expression plasmids were able to inhibit significantly the expression of ORF 7 gene and replication of TGEV, as shown by real-time quantitative RT-PCR analysis of viral ORF 7 and N genes and detection of virus titers (TCID50/ml). Stable swine testicular (ST) cells expressing the shRNAs were established. Observation of the cytopathic effect and apoptosis, as well as a cell proliferation assay demonstrated that the three shRNAs were capable of protecting ST cells against TGEV destruction, with high specificity and efficiency.
  
  
  CONCLUSIONS
  Our results indicated that plasmid-transcribed shRNAs targeting the ORF 7 gene in the TGEV genome effectively inhibited expression of the viral target gene and viral replication in vitro. These findings provide evidence that the shRNAs have potential therapeutic application for treatment of TGE.
authors.affiliation: College of Veterinary Medicine, Northwest A & F University, Yangling, Shaanxi 712100, China.
authors.forename: Lei
authors.initials: L
authors.lastname: He
authors.forename: Yan-ming
authors.initials: YM
authors.lastname: Zhang
authors.forename: Ling-juan
authors.initials: LJ
authors.lastname: Dong
authors.forename: Min
authors.initials: M
authors.lastname: Cheng
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.forename: Qing-hai
authors.initials: QH
authors.lastname: Tang
authors.forename: Gang
authors.initials: G
authors.lastname: Wang
mesh_terms: D000818:Animals; D000998:Antiviral Agents / Q000378:metabolism*; D001688:Biological Products / Q000378:metabolism*; D002460:Cell Line; D017934:Coronavirus / Q000235:genetics / Q000502:physiology*; D005761:Gastroenteritis, Transmissible, of Swine / Q000821:virology*; D010957:Plasmids; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism*; D012367:RNA, Viral / Q000032:analysis / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D013552:Swine; D014779:Virus Replication
chemical_list: D000998:Antiviral Agents; D001688:Biological Products; D034741:RNA, Small Interfering; D012367:RNA, Viral