Several fenpropathrin-resistant predatory mites have been reported. However, the molecular mechanism of the resistance remains unknown. In the present study, the Neoseiulus barkeri (N. barkeri) transcriptome was generated using the Illumina sequencing platform, 34,211 unigenes were obtained, and 15,987 were manually annotated. After manual annotation, attentions were attracted to resistance-related genes, such as voltage-gated sodium channel (VGSC), cytochrome P450s (P450s), and glutathione S-transferases (GSTs). A polymorphism analysis detected two point mutations (E1233G and S1282G) in the linker region between VGSC domain II and III. In addition, 43 putative P450 genes and 10 putative GST genes were identified from the transcriptome. Among them, two P450 genes, NbCYP4EV2 and NbCYP4EZ1, and four GST genes, NbGSTd01, NbGSTd02, NbGSTd03 and NbGSTm03, were remarkably overexpressed 3.64-46.69-fold in the fenpropathrin resistant strain compared to that in the susceptible strain. These results suggest that fenpropathrin resistance in N. barkeri is a complex biological process involving many genetic changes and provide new insight into the N. barkeri resistance mechanism.
Keywords: GST; Neoseiulus barkeri; P450; VGSC; fenpropathrin resistant; transcriptome.