Figure 2. Knockdown of the C002 transcript after siRNA injections. Insects were injected either with siC002-RNA or siGFP-RNA. RNA from heads of injected insects was used in RT-PCR in which two primer-pairs were included, for C002 itself and for the transcript encoding ribosomal protein L27. The L27 PCR product serves as an internal control. The results shown (agarose gels after ethidium bromide staining) are of individual aphids at time points from 1 to 5 days after injection. Panel A: PCR products from reactions (26 cycles) with head RNA from siC002-RNA-injected insects. Panel B: PCR products from reactions (26 cycles) with head RNA from siGFP-RNA-injected insects. Panel C: PCR products from reactions (26 cycles) carried out on RNA extracted from heads from which salivary glands had been removed. Analysis of samples from 4 separate insects are shown.