Silencing of CYP6AS160 in Solenopsis invicta Buren by RNA interference enhances worker susceptibility to fipronil

Abstract Cytochrome P450 monooxygenases play a key role in pest resistance to insecticides by detoxification. Four new P450 genes, CYP6AS160, CYP6AS161, CYP4AB73 and CYP4G232 were identified from Solenopsis invicta. CYP6AS160 was highly expressed in the abdomen and its expression could be induced significantly with exposure to fipronil, whereas CYP4AB73 was not highly expressed in the abdomen and its expression could not be significantly induced following exposure to fipronil. Expression levels of CYP6AS160 and CYP4AB73 in workers were significantly higher than that in queens. RNA interference-mediated gene silencing by feeding on double-stranded RNA (dsRNA) found that the levels of this transcript decreased (by maximum to 64.6%) when they fed on CYP6AS160-specific dsRNA. Workers fed dsCYP6AS160 had significantly higher mortality after 24 h of exposure to fipronil compared to controls. Workers fed dsCYP6AS160 had reduced total P450 activity of microsomal preparations toward model substrates p-nitroanisole. However, the knockdown of a non-overexpressed P450 gene, CYP4AB73 did not lead to an increase of mortality or a decrease of total P450 activity. The knockdown effects of CYP6AS160 on worker susceptibility to fipronil, combined with our other findings, indicate that CYP6AS160 is responsible for detoxification of fipronil. Feeding insects dsRNA may be a general strategy to trigger RNA interference and may find applications in entomological research and in the control of insect pests in the field.

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Red imported fire ant invasion reduces the populations of two banana insect pests in South China

Sociobiology ◽

10.13102/sociobiology.v63i3.1035 ◽

2016 ◽

Vol 63 (3) ◽

pp. 889 ◽

Cited By ~ 4

Author(s):

Lei Wang ◽

Zheng Wang ◽

Ling Zeng ◽

Yongyue Lu

Keyword(s):

South China ◽

Solenopsis Invicta ◽

Insect Pests ◽

Fire Ant ◽

Invasive Pest ◽

Red Imported Fire Ant ◽

Solenopsis Invicta Buren ◽

Banana Plantations ◽

Imported Fire Ant

As a severe invasive pest, red imported fire ant (Solenopsis invicta Buren) had important effects on ecosystem of its infected areas. Here, we surveyed impact of S. invicta on populations of two banana insect pests, banana skipper (Erion tatorus Evans) and banana stephanitis (Stephanitis typical Distant). The results showed that influences of S. invicta on population of E. tatorus and S. typical depend on weed coverage degree of banana plantations. Comparing to the areas without S. invicta, banana skipper population was reduced by 39.2%, 41.4% and 23.4% respectively, in high, moderate and low weed coverage of banana plantations with S. invicta invasion. Banana stephanitis population was reduced by 17.8%, 43.0% and 39.2% respectively, in high, moderate and low weed coverage of banana plantations with S. invicta invasion.

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The Role of Cytochrome P450s in Insect Toxicology and Resistance

Annual Review of Entomology ◽

10.1146/annurev-ento-070621-061328 ◽

2021 ◽

Vol 67 (1) ◽

Author(s):

Ralf Nauen ◽

Chris Bass ◽

René Feyereisen ◽

John Vontas

Keyword(s):

Cytochrome P450 ◽

Insecticide Resistance ◽

Insect Pests ◽

Cytochrome P450s ◽

Cytochrome P450 Monooxygenases ◽

Annual Review ◽

Publication Date ◽

Beneficial Insects ◽

P450 Monooxygenases

Insect cytochrome P450 monooxygenases (P450s) perform a variety of important physiological functions, but it is their role in the detoxification of xenobiotics, such as natural and synthetic insecticides, that is the topic of this review. Recent advances in insect genomics and postgenomic functional approaches have provided an unprecedented opportunity to understand the evolution of insect P450s and their role in insect toxicology. These approaches have also been harnessed to provide new insights into the genomic alterations that lead to insecticide resistance, the mechanisms by which P450s are regulated, and the functional determinants of P450-mediated insecticide resistance. In parallel, an emerging body of work on the role of P450s in defining the sensitivity of beneficial insects to insecticides has been developed. The knowledge gained from these studies has applications for the management of P450-mediated resistance in insect pests and can be leveraged to safeguard the health of important beneficial insects. Expected final online publication date for the Annual Review of Entomology, Volume 67 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

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Identification of a novel cytochrome P450 gene,CYP321E1from the diamondback moth,Plutella xylostella(L.) and RNA interference to evaluate its role in chlorantraniliprole resistance

Bulletin of Entomological Research ◽

10.1017/s0007485314000510 ◽

2014 ◽

Vol 104 (6) ◽

pp. 716-723 ◽

Cited By ~ 29

Author(s):

Z. Hu ◽

Q. Lin ◽

H. Chen ◽

Z. Li ◽

F. Yin ◽

...

Keyword(s):

Cytochrome P450 ◽

Rna Interference ◽

Plutella Xylostella ◽

Developmental Stages ◽

Diamondback Moth ◽

Fourth Instar ◽

Cytochrome P450 Monooxygenases ◽

Functional Link ◽

Cytochrome P450 Gene ◽

P450 Gene

AbstractInsect cytochrome P450 monooxygenases (P450s) play an important role in catalysis of many reactions leading to insecticides resistance. Our previous studies on transcriptome analysis of chlorantraniliprole-resistant development in the diamondback moth,Plutella xylostellarevealed that up-regulation of cytochrome P450s are one of the main factors leading to the development of chlorantraniliprole resistance. Here, we report for the first time a novel cytochrome P450 geneCYP321E1, which belongs to the cytochrome P450 gene family CYP321. Real-time quantitative PCR (RT–qPCR) analyses indicated thatCYP321E1was expressed at all developmental stages ofP. xylostellabut was highest in the fourth-instar larvae; furthermore, the relatively high expression was observed in the midgut of the fourth-instar larvae, followed by fat bodies and epidermis. The expression ofCYP321E1inP. xylostellawas differentially affected by three representative insecticides, including alphamethrin, abamectin and chlorantraniliprole. Among them, the exposure to chlorantraniliprole resulted in the largest transcript level of this cytochrome P450 gene. The findings suggested potential involvement ofCYP321E1in chlorantraniliprole resistance ofP. xylostella. To assess the functional link ofCYP321E1to chlorantraniliprole resistance, RNA interference (RNAi)-mediated gene silencing by double stranded RNA (dsRNA) injecting was used. Results revealed that injection delivery of dsRNA can greatly reduce gene expression after 24 h. As a consequence of RNAi, a significant increment in mortality of larvae injectedCYP321E1dsRNA was observed after 24 h of exposure to chlorantraniliprole. These results strongly support our notion that this novel cytochrome P450 gene plays an important role in chlorantraniliprole detoxification in the diamondback moth and is partly responsible for its resistance.

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Cytochrome P450 monooxygenases and insecticide resistance in insects

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.1998.0321 ◽

1998 ◽

Vol 353 (1376) ◽

pp. 1701-1705 ◽

Cited By ~ 131

Author(s):

J. Bergé ◽

R. Feyereisen ◽

M. Amichot

Keyword(s):

Cytochrome P450 ◽

Insecticide Resistance ◽

3D Structure ◽

Resistance Mechanisms ◽

Cytochrome P450 Monooxygenases ◽

Wild Type ◽

P450 Gene ◽

P450 Monooxygenases ◽

Loss Of Resistance ◽

Cytochrome P450 Genes

Cytochrome P450 monooxygenases are involved in many cases of resistance of insects to insecticides. Resistance has long been associated with an increase in monooxygenase activities and with an increase in cytochrome P450 content. However, this increase does not always account for all of the resistance. In Drosophila melanogaster , we have shown that the overproduction of cytochrome P450 can be lost by the fly without a corresponding complete loss of resistance. These results prompted the sequencing of a cytochrome P450 candidate for resistance in resistant and susceptible flies. Several mutations leading to amino–acid substitutions have been detected in the P450 gene CYP6A2 of a resistant strain. The location of these mutations in a model of the 3D structure of the CYP6A2 protein suggested that some of them may be important for enzyme activity of this molecule. This has been verified by heterologous expression of wild–type and mutated cDNA in Escherichia coli . When other resistance mechanisms are considered, relatively few genetic mutations are involved in insecticide resistance, and this has led to an optimistic view of the management of resistance. Our observations compel us to survey in more detail the genetic diversity of cytochrome P450 genes and alleles involved in resistance.

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Interactions Between Solenopsis invicta (Buren) and Monomorium minimum (Buckley) under Varying Distance and Feeding Status

Southwestern Entomologist ◽

10.3958/0147-1724-32.2.111 ◽

2007 ◽

Vol 32 (2) ◽

pp. 111-125 ◽

Cited By ~ 1

Author(s):

Asha Rao ◽

S. Bradleigh Vinson

Keyword(s):

Solenopsis Invicta ◽

Solenopsis Invicta Buren

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Activation modes in biocatalytic radical cyclization reactions

Journal of Industrial Microbiology & Biotechnology ◽

10.1093/jimb/kuab021 ◽

2021 ◽

Author(s):

Yuxuan Ye ◽

Haigen Fu ◽

Todd K Hyster

Keyword(s):

Heme Iron ◽

Radical Cyclization ◽

Cytochrome P450 Monooxygenases ◽

Radical Cyclizations ◽

Cyclization Reactions ◽

Complex Molecules ◽

P450 Monooxygenases ◽

Non Heme Iron ◽

Essential Reactions ◽

Isopenicillin N

Abstract Radical cyclizations are essential reactions in the biosynthesis of secondary metabolites and the chemical synthesis of societally valuable molecules. In this review, we highlight the general mechanisms utilized in biocatalytic radical cyclizations. We specifically highlight cytochrome P450 monooxygenases (P450s) involved in the biosynthesis of mycocyclosin and vancomycin, non-heme iron- and α-ketoglutarate-dependent dioxygenases (Fe/αKGDs) used in the biosynthesis of kainic acid, scopolamine, and isopenicillin N, and radical S-adenosylmethionine (SAM) enzymes that facilitate the biosynthesis of oxetanocin A, menaquinone, and F420. Beyond natural mechanisms, we also examine repurposed flavin-dependent ‘ene’-reductases (ERED) for non-natural radical cyclization. Overall, these general mechanisms underscore the opportunity for enzymes to augment and enhance the synthesis of complex molecules using radical mechanisms.

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