Impact of sid-3 and viro-2 on Orsay virus RNA1 transgene-initiated replication. (A) Imaging of heat-induced strains carrying either wild-type or mutant Orsay virus RNA1 in the jyIs8;rde-1 background. BF, bright-field microscopy. Bars, 200 μm. (B) Imaging of heat-induced strains carrying either wild-type or mutant Orsay virus RNA1 in the sid-3(vir9) background. Bars, 200 μm. (C) Quantification of Orsay RNA1 replication from heat-induced transgenic C. elegans. To control for possible variability in the copy number of the extrachromosomal arrays, two independent lines for each plasmid construct were tested. NS, not significant (P > 0.05).