Common and Distinct Roles of Juvenile Hormone Signaling Genes in Metamorphosis of Holometabolous and Hemimetabolous Insects
Figure 2
Loss of Met or Kr-h1 causes precocious metamorphosis in Pyrrhocoris larvae.
A) Larvae newly ecdysed to the L4 instar were injected with control (egfp) or Met dsRNA. B) Efficacy of Met mRNA depletion and its effect on expression of Kr-h1 and BR-C expression were determined by qRT-PCR three days after injection of Met dsRNA (gray columns) relative to egfp dsRNA controls (open columns) arbitrarily set to 100%. Values are mean ± SD from n = 5 animals. C) Met, Kr-h1 and BR-C RNAi phenotypes after ecdysis to the L5 stage as compared to control L5 larvae and adults (left two columns). Animals in the top row are to the same scale; the middle and bottom rows show details of wings and of the ventral abdomen, respectively. Precocious adult attributes upon Met and Kr-h1 RNAi include color-patterned articulated wings (arrows) separated from the scutellum (s), extended notum (open arrowheads) with two posterior black spots, external male genitals (solid arrowheads), and dark abdominal cuticle (asterisks). Compared to control L5, BR-C(RNAi) larvae display retarded wing growth but no precocious adult development. For quantitative data see Table 1. (Scale bars: A and C, top row, 3 mm; C, middle row, 1 mm; C, bottom row, 2 mm).