The role of G protein‐coupled receptor‐related genes in cytochrome P450‐mediated resistance of the house fly, Musca domestica (Diptera: Muscidae), to imidacloprid

Abstract

Ninety‐four putative G protein‐coupled receptors (GPCRs) were identified in the Musca domestica genome. They were annotated and compared with their homologues in Drosophila melanogaster. Phylogenetic analyses of the GPCRs from both species revealed that several family members shared a closer relationship based on the domain architecture. The expression profiles of these genes were examined by quantitative real‐time PCR amongst three strains of the house fly, a near‐isogenic line strain with imidacloprid resistance (N‐IRS), the corresponding susceptible strain (CSS) and another strain derived from field populations with imidacloprid resistance (IRS). We found that five GPCR genes were upregulated in the N‐IRS and eight GPCR genes were upregulated in the IRS strains compared to the CSS strain. The transgenic lines of D. melanogaster with the GPCR genes (LOC101899380 in the N‐IRS strain and LOC101895664 in the IRS strain) exhibited significantly increased tolerance to imidacloprid, and higher expression of cytochrome P450 genes. Bioinformatic analysis of LOC101899380 was carried out based on its full‐length nucleic acid sequence and putative amino acid sequence, and it was named Methuselah‐like10 (Mthl10) owing to its homology with D. melanogaster Mthl10. A cell‐base cell counting kit‐8 toxicity assay demonstrated that the expression of the GPCR gene LOC101899380 in Spodoptera frugiperda (Sf9) cells using a baculovirus‐mediated expression system can elevate the cell tolerance to imidacloprid, indirectly supporting the hypothesis that the GPCR gene LOC101899380 plays some role in imidacloprid resistance. These results should be useful for furthering understanding of the regulatory pathway by which house flies develop resistance.

G-Protein Coupled Receptors (GPCRs) in Insects—A Potential Target for New Insecticide Development

“…quinquefasciatus, around 115 GPCR genes have been identified, with 52 belonging to Class A (the rhodopsin-like family), 4 to Class B (the secretin-like family) and the rest not been classified [42]. For Musca domestica, around 94 genes have been identified as GPCR genes, 55 of which are classified as Class A (the rhodopsin-like family), 27 are classified as Class B (the secretin-like family), 4 are classified as Class C (the metabotropic glutamate-like family) and the rest are still unclear [72] (Table 1, Figure 1). [72] In addition to the insects above that have been extensively studied, GPCRs from several other insect species have also been identified and annotated.…”

There is more than chitin synthase in insect resistance to benzoylureas: Molecular markers associated with teflubenzuron resistance inSpodoptera frugiperda

“…An exploration of GPCRs in Tribolium castaneum indicated mth is also important for larval molt and metamorphosis (Bai, Zhu, Shah, & Palli, 2011). Moreover, mth gene mutation led D. melanogaster to become tolerant to dichlorvos (Pandey et al, 2015), but insect response to insecticide exposure was also altered with changes in the levels of mth expression (Cao et al, 2019; Li et al, 2015; Lucas et al, 2019; Ma, Zhang, You, Zeng, & Gao, 2020). Similarly to the early discussed synergism of ABCCs and phase II conjugation enzymes in insect response to insecticide exposure, mth is co-expressed with the phase I detoxification P450 enzymes, contributing to insect resistance to insecticides (Cao et al, 2019; Li et al, 2015).…”

Are insect GPCRs ideal next‐generation pesticides: opportunities and challenges

“…Given that pathogen vectors have been evolving rapidly in response to the selective pressure exerted by over a century by insecticide use, novel chemicals must be developed to reduce the incidence of resistance. Accordingly, several studies have demonstrated that some insect GPCRs and their intracellular downstream pathways are highly associated with pesticide resistance [111,[140][141][142]. In Culex quinquefasciatus, 115 GPCRs and GPCR-related genes were studied in both resistant and susceptible strains to detect insecticide resistance-linked candidates.…”

“…Repression of these GPCRs also caused the downregulation of certain insecticide resistance‐linked P450 genes [140]. Recently, a study on Musca domestica discovered an upregulated GPCR gene called LOC101899380 responsible for enhanced tolerance against imidacloprid and elevated expression of P450 genes in near‐isogenic lines with imidacloprid resistance (N‐IRS) [142]. Further bioinformatic analysis revealed that LOC101899380 shares homology with Methuselah‐like 10 (Mthl10) in D. melanogaster .…”

“…Further bioinformatic analysis revealed that LOC101899380 shares homology with Methuselah‐like 10 (Mthl10) in D. melanogaster . Exogenous expression of the discovered GPCR in Spodoptera frugiperda (Sf9) cells resulted in enhanced tolerance to imidacloprid [142]. The link between certain GPCRs and P450 genes was disclosed by several studies by which GPCR/G protein alpha subunit (Gαs)/adenylate cyclase (AC)/protein kinase A (PKA)/P450 genes forms signal transduction pathway in Cu.…”