Natural and Experimental Infection of Caenorhabditis Nematodes by Novel Viruses Related to Nodaviruses (original) (raw)
Figure 8
Natural variation in somatic RNAi efficacy in C. elegans.
(A) Somatic RNAi was tested using bacteria expressing dsRNA specific for the unc-22 gene (acting in muscle; [37]). The percentage of animals with the corresponding twitcher phenotype is shown for different C. elegans wild isolates (representative of the species' diversity; [38]). Bar: standard error over four replicate plates. (B) Germline RNAi was tested by feeding the animals with bacteria expressing dsRNA specific for the pos-1 gene. The percentage of animals with the corresponding embryonic-lethal phenotype is shown for five wild genetic backgrounds of C. elegans. Cbr-lin-12 RNAi is a negative control. Bar: standard error over six replicate plates (too small to be seen). _n_>450 observed individuals for each treatment. (C) Somatic RNAi was tested using bacteria expressing dsRNA specific for GFP. Each point corresponds to the median log2(GFP/DsRed) intensity ratio from one flow cytometry run of strains carrying the let-858::GFP transgene in the JU1580 and N2 backgrounds, after treatment with GFP RNAi or empty vector. Horizontal bars indicate group means. The difference in log2 intensity ratios between GFP RNAi and empty vector is reduced in JU1580 compared to N2 (p<0.001, see Methods). (D) unc-22 dsRNA was administered by injection into the syncytial germline of the mother. 10–14 animals of each genotype were injected and 30 progeny were scored for the twitcher phenotype on each plate. (E) Orsay virus sensitivity of seven wild C. elegans isolates representative of the species' diversity. Morphological symptoms were scored 5 d after infection of clean cultures by the Orsay virus filtrate at 23°C. The JU1580 control was performed in duplicate. Bar: standard error on total proportion. *** p<0.001.