Antiviral activity of small interfering RNAs: specificity testing using heterologous virus reveals interferon-related effects overlooked by conventional mismatch controls.
RNA interference by small interfering RNAs (siRNAs) is considered to be a highly specific method for knockdown of gene expression in eukaryotic cells via degradation of target mRNA. Mutated siRNA molecules with 1-4 mismatching nucleotides compared to the target mRNA are regularly used as specificity controls. Using siRNAs for inhibition of a fish-pathogenic rhabdovirus, we report that inclusion of a heterologous virus, as target control is essential for verification of the specificity of siRNA-induced interference with virus multiplication. Transfection with three different siRNAs specific to the viral glycoprotein gene of the target-virus efficiently inhibited viral multiplication in infected cell cultures, while two of three corresponding mismatched siRNAs did not have this effect. This suggested specific interference, but similar results were obtained when the same siRNAs were tested against a heterologous virus. Further analyses revealed that the siRNAs induced a non-target-specific anti-viral effect correlating with upregulation of the interferon induced Mx gene.
Danish Institute for Food and Veterinary Research, Hangøvej 2, 8200 Arhus N, Denmark. bds@dfvf.dk
Brian Dall
BD
Schyth
Niels
N
Lorenzen
Finn Skou
FS
Pedersen
D000818:Animals; D000998:Antiviral Agents; D002460:Cell Line; D005399:Fishes; D019204:GTP-Binding Proteins / Q000096:biosynthesis / Q000235:genetics; D007372:Interferons / Q000502:physiology*; D064547:Myxovirus Resistance Proteins; D034622:RNA Interference; D012333:RNA, Messenger / Q000032:analysis; D034741:RNA, Small Interfering / Q000502:physiology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012209:Rhabdoviridae / Q000235:genetics* / Q000502:physiology*; D012680:Sensitivity and Specificity; D015854:Up-Regulation; D014779:Virus Replication
D000998:Antiviral Agents; D064547:Myxovirus Resistance Proteins; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D007372:Interferons; D019204:GTP-Binding Proteins