Involvement of microRNA miR‐2b‐3p in regulation of metabolic resistance to insecticides in Plutella xylostella

Abstract

The diamondback moth, Plutella xylostella, has developed extremely high levels of resistance to chlorantraniliprole and other classes of insecticides in the field. As microRNAs (miRNAs) play important roles in various biological processes through gene regulation, we examined the miRNA profile of P. xylostella in response to chlorantraniliprole exposure. RNA sequencing analysis showed that insecticide treatment caused significant changes in the abundance of some miRNAs. Increasing exposure time and insecticide concentration induced more dysregulated miRNAs in P. xylostella larvae. We also screened potential target genes for some of the differentially expressed miRNAs (such as miR-2b-3p, miR-14b-5p and let-7-5p), which may play important roles in insecticide resistance development. Exposure of P. xylostella larvae to chlorantraniliprole caused considerable overexpression in the transcript levels of potential target genes cytochrome P450 9f2 (CYP9F2) and 307a1 (CYP307a1). Application of miR-2b-3p and miR-14b-5p mimics significantly suppressed the relative transcript levels of CYP9F2 and CYP307a1, respectively, in a P. xylostella cell line. Furthermore, enrichment of P. xylostella diet with miR-2b-3p mimics significantly increased mortality in deltamethrin-resistant larvae when exposed to deltamethrin. The results suggest that miR-2b-3p may suppress CYP9F2 transcript levels in P. xylostella and consequently inhibit larval detoxification pathways. The findings provide an insight into possible role of miRNAs in regulation of metabolic resistance of insects to insecticides.

Post-transcriptional modulation of cytochrome P450s, Cyp6g1 and Cyp6g2, by miR-310s cluster is associated with DDT-resistant Drosophila melanogaster strain 91-R

“…Arthropods continue to damage agricultural commodities and vector diseases threatening human welfare due to ongoing challenges in pest control that arise from instances where selection has caused high levels of resistance following repeated exposures to insecticidal agents. The involvement of miRNAs in the regulation of metabolic resistance to insecticides has been suggested via comparative and correlative studies for pyrethroids 29 and ryanoids 30 , but strong evidence for miRNAs as causative factors among these resistant phenotypes is arguably lacking. The present study demonstrated that members for the miR-310s cluster interact with target binding sites within 3ʹ-UTR sequences of cytochrome P450, thereby regulating transcript levels in vivo.…”

Transcription factors CncC/Maf and AhR/ARNT coordinately regulate the expression of multiple GSTs conferring resistance to chlorpyrifos and cypermethrin inSpodoptera exigua

“…Previous work has shown that overproduction of detoxification enzymes is an important mechanism for insecticide resistance and complex regulatory mechanisms are involved in the up‐regulated expression of resistance‐associated detoxification genes, such as cis ‐regulatory elements and/or trans ‐acting factors, microRNAs and GPCR signaling cascades . The up‐regulation of CYP6FU1 conferring deltamethrin resistance in Laodelphax striatellus involves multiple cis ‐regulatory elements .…”

miRNA-Mediated Interactions in and between Plants and Insects

“…Caterpillars of the diamondback moth, Plutella xylostella , are highly destructive pests of Brassica crops [ 58 ]. Several miRNA species that regulate resistance to the ryanoid insecticide chlorantraniliprole were identified in this insect [ 59 ]. miR-2b-3p and miR-14b-5p post-translationally suppress two cytochrome P 450 monooxygenase genes, CYP9F2 and CYP307a1 , respectively, which are most likely involved in insecticide detoxification [ 59 ].…”

“…Several miRNA species that regulate resistance to the ryanoid insecticide chlorantraniliprole were identified in this insect [ 59 ]. miR-2b-3p and miR-14b-5p post-translationally suppress two cytochrome P 450 monooxygenase genes, CYP9F2 and CYP307a1 , respectively, which are most likely involved in insecticide detoxification [ 59 ]. A diet containing miR-2b-3p mimics provided to a P. xylostella line resistant to the pyrethroid insecticide deltamethrin results in greater lethality, presumably because miRNA-mediated suppression of cytochrome P 450 enzyme decreases the insect ability to detoxify the pesticide.…”