Expression patterns of SeABCC2 or SeABCC3 gene in different developmental stages (A) and in different tissues (B) of the fifth instar larvae in S. exigua . ‘E’, ‘L1 – L5’, ‘P’, and ‘A’ represent egg, larval instars, pupa, and adult, respectively. ‘FB’, ‘HC’, ‘NV’, and ‘SG’ represent fat body, hemocytes, nerve, and salivary gland, respectively. Expression of β-actin confirms the integrity of cDNA preparation. Toxicity comparison of Cry1Ac and Cry1Ca protoxins against third instar larvae of S. exigua (C). Each bioassay was conducted with ten larvae per replicate and three replicates per concentration. Mortality was scored at five days post-treatment. Suppression of SeABCC2 or SeABCC3 gene expression using a specific double-stranded RNA (dsSeABCC2 or dsSeABCC3) in the whole body of S. exigua larvae at different periods (D and E, respectively). SeABCC2 or SeABCC3 expression was analyzed by qRT-PCR. Each treatment was independently replicated three times. Different letters above standard deviation bars indicate significant differences among means at Type I error = 0.05 (LSD test). The effect of suppression of SeABCC2 or SeABCC3 gene expression on susceptibility of the third instar S. exigua to Cry1Ac or Cry1Ca protoxins (F). A viral gene (ORF302)-specific dsRNA (dsCON) was used for a dsRNA control. At 24 hours after dsRNA treatment, the larvae were exposed to Cry1Ac (10 μg/cm2) or Cry1Ca (1 μg/cm2) protoxins treated by the leaf-dipping method. Mortality was assessed at five days after Cry toxin treatment. Each treatment was replicated three times. Each replication used 10 larvae. Different letters above standard deviation bars indicate significant difference among means at Type I error = 0.05 (LSD test). dsRNA, double-stranded RNA; LSD, least significant difference; qRT-PCR, quantitative reverse transcriptase-polymerase chain reaction.