Effect on main functional genes expression and replication of Chinese giant salamander ranavirus (CGSRV) by RNA interference

We used qPCR and virus titer determination to investigate the effects on MCP, MTases and DNA polymerase gene expression, as well as replication of Chinese giant salamander ranavirus (CGSRV) by RNA interference (RNAi). The results show that small interfering RNA (siRNA) delayed and reduced the cytopathic effects. Among the expression quantity of each functional genes, NC-FAM control group had no significant change (P>0.05) but the interference rates of interferential experiment groups were higher than that of negative control group. The interference rate of siR-DP-1 group on MCP genes was 79%, very significantly higher than those of the other groups (P < 0.01);the interference rate of siR-MT-1 or siR-MT-2 group on MTases genes was 77%, very significantly higher than those of the other groups (P < 0.01);the interference rate of siR-DP-1 group on DNA polymerase genes was 79%, very significantly higher than those of the other groups (P < 0.01). The viral titers of interferential experiment groups inordinately decreased compared with those of the other groups. Furthermore, the lgTCID₅₀s of negative control group and NC-FAM control group were 8.362 and 7.848, respectively, and the lowest lgTCID₅₀s of siR-MCP, siR-MT and siR-DP groups were 5.764, 5.317 and 5.362, respectively. In conclusion, RNA interference inhibits the main functional genes expression and replication of CGSRV.