Figure 3. A synthetic RNAi-resistant pico transgene rescues the phenotypic effect of ectopic picoRNAi^IR4 but not picoRNAi^R3.

A) Expression of a synthetic, Venus-tagged, pico transgene is not affected by co-expression of picoRNAi constructs. Confocal images of wing imaginal discs from flies expressing UAS-Venus-pico^r alone (MS1096>Venus-pico^r), or together with UAS-picoRNAi constructs (MS1096>Venus-pico^r, picoRNAi^R3 or MS1096>Venus-pico^r, picoRNAi ^IR4) are shown. DNA staining with TO-PRO-3 (magenta in the merged image) reveals that each image is of a similar section through the disc, whilst the Venus signal (green in the merged image) reveals that the levels of Venus-pico^r are largely unaffected by co-expression with the pico inverted repeat constructs. B) Ectopic expression of Venus-pico^r rescues the growth defect resulting from picoRNAi^IR4, but not the wing dysmorphology phenotype displayed by picoRNAi^R3. Ectopic Venus-pico^r under the control of MS1096-GAL4 (MS1096>Venus-pico^r) results in an increase in wing size. Ectopic picoRNAi^R3 (MS1096> picoRNAi^R3) results in a crumpled wing (similar to the effect of co-expressing picoRNAi^R2 and picoRNAi^IR3, as in Figure 1C), and this is not suppressed by Venus-pico^r (MS1096>Venus-pico^r, picoRNAi^R3). In contrast, coexpression of Venus-pico^r and picoRNAi^IR4 (MS1096>Venus-pico^r, picoRNAi^IR3) resembles the effect of Venus-pico^r alone.