CncC regulated genes code for proteins involved in all three phases of insecticide detoxification in Tribolium Castaneum

In invertebrates, a heterodimer of xenobiotic transcription factors, cap n collar C isoform (CncC) and muscle aponeurosis fibromatosis (Maf) mediate cellular defense. In insects, these proteins regulate expression of genes involved in insecticide detoxification. In the current study, we performed sequencing of RNA isolated from Tribolium castaneum pyrethriod resistant strain (QTC279) beetles injected with CncC or green fluroscence protein (GFP, control) dsRNA. Differential expression analysis of RNA sequences identified 662 genes that showed a decrease and 91 genes that showed an increase in expression (at a p value <0.01 and log2 fold change of >1.5) in CncC knockdown insects when compared to their expression in control insects. We focused on the downregulated genes and selected a subset of 27 genes (21 with a predicted function in xenobiotic detoxification and six randomly picked) and verified their differential expression using qRT-PCR. RNAi and insecticide bioassays were employed to study the function of six of these genes coding for CYP4G7, CYP4G14, GST-1 and four ABC transporters, ABCA-UB, ABCA-A1 and ABCA-A1L and ABCA-9B involved in all three phases of insecticide detoxification. These data suggest that CncC is a major regulator of genes coding for proteins involved in detoxification of insecticides.In invertebrates, a heterodimer of xenobiotic transcription factors, cap n collar C isoform (CncC) and muscle aponeurosis fibromatosis (Maf) mediate cellular defense. In insects, these proteins regulate expression of genes involved in insecticide detoxification. In the current study, we performed sequencing of RNA isolated from Tribolium castaneum pyrethriod resistant strain (QTC279) beetles injected with CncC or green fluroscence protein (GFP, control) dsRNA. Differential expression analysis of RNA sequences identified 662 genes that showed a decrease and 91 genes that showed an increase in expression (at a p value <0.01 and log2 fold change of >1.5) in CncC knockdown insects when compared to their expression in control insects. We focused on the downregulated genes and selected a subset of 27 genes (21 with a predicted function in xenobiotic detoxification and six randomly picked) and verified their differential expression using qRT-PCR. RNAi and insecticide bioassays were employed to study the function of six of these genes coding for CYP4G7, CYP4G14, GST-1 and four ABC transporters, ABCA-UB, ABCA-A1 and ABCA-A1L and ABCA-9B involved in all three phases of insecticide detoxification. These data suggest that CncC is a major regulator of genes coding for proteins involved in detoxification of insecticides.

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