Cis-acting mutation and duplication: History of molecular evolution in a P450 haplotype responsible for insecticide resistance in Culex quinquefasciatus

Itokawa, Kentaro; Komagata, Osamu; Kasai, Shinji; Morimoto, Masahiro; Tomita, Takashi

doi:10.1016/j.ibmb.2011.04.002

Cited by 36 publications

(52 citation statements)

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“…The duplication of CYP9M10 described previously in the JPAL strain (Itokawa et al, 2011;Itokawa et al, 2010) could be a cryptic variable in studies of resistance association. To investigate this, a subset of Ghanaian samples (N = 24) was analysed for the presence of the duplicated CYP9M10 (CYP9M10v2) using the Gen2F PCR of Itokawa et al (2010).…”

Section: Association Of the Mite Insertion Upstream Of Cyp9m10 With Pmentioning

confidence: 85%

“…The ISOP450 sequence differs from the CqSF strain at 10 amino acids (R143G, M156T, L232V, I245F, V279M, M288I, E289D, K356M, S422T, D445N). Critically, CYP9M10 from both ISOP450 and CqSF encode full-length transcripts as does the Johannesburg reference strain (Itokawa et al 2011). Therefore relatively greater susceptibility cannot be ascribed simply to a non-functional version of CYP9M10 in CqSF, unlike the Ogasawara susceptible strain studied previously (Itokawa et al, 2010), which contains a deletion resulting in a premature stop codon.…”

Section: Gene Expression and Sequencing Of Cyp9m10 And Cyp4h34mentioning

confidence: 98%

“…quinquefasciatus was established from Saudi Arabia (Amin and Hemingway, 1989) and exhibits high resistance in the aquatic larval stage to permethrin (a class I pyrethroid) but relatively low resistance to class II pyrethroids such as deltamethrin (resistance ratios of 2,500 and 56 respectively, compared to the susceptible Ogasawara lab strain (Weerasinghe et al, 2001)). In a series of experiments Tomita and colleagues implicated mutations in the sodium channel (L1014F), the target-site of permethrin, and increased expression of cytochrome P450s as the likely causes of the permethrin resistant phenotype (Itokawa et al, 2011;Itokawa et al, 2010;Komagata et al, 2010) in JPAL. Using a custom microarray incorporating probes for 197 genes including 62 CYP450s, three genes, CYP9M10, CYP4H34 and CYP6Z10, were detected as up-regulated (39.2, 5.6 and 2.6 fold respectively) in JPAL relative to the Ogasawara strain .…”

Section: Introductionmentioning

confidence: 99%

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A cis-regulatory sequence driving metabolic insecticide resistance in mosquitoes: Functional characterisation and signatures of selection

Wilding

Smith

Lynd

et al. 2012

Insect Biochemistry and Molecular Biology

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Although cytochrome P450 (CYP450) enzymes are frequently up-regulated in mosquitoes resistant to insecticides, no regulatory motifs driving these expression differences with relevance to wild populations have been identified. Transposable elements (TEs) are often enriched upstream of those CYP450s involved in insecticide resistance, leading to the assumption that they contribute regulatory motifs that directly underlie the resistance phenotype. A partial CuRE1 (Culex Repetitive Element 1) transposable element is found directly upstream of CYP9M10, a cytochrome P450 implicated previously in larval resistance to permethrin in the ISOP450 strain of Cx. quinquefasciatus, but is absent from the equivalent genomic region of a susceptible strain. Via expression of CYP9M10 in E.coli we have now demonstrated time-and NADPH-dependant permethrin metabolism, prerequisites for confirmation of a role in metabolic resistance, and through qPCR shown that CYP9M10 is >20-fold over-expressed in ISOP450 compared to a susceptible strain. In a fluorescent reporter assay the region upstream of CYP9M10 from ISOP450 drove 10x expression compared to the equivalent region (lacking CuRE1) from the susceptible strain. Close correspondence with the gene expression fold-change implicates the upstream region including CuRE1 as a cis-regulatory element involved in resistance. Only a single CuRE1 bearing allele, identical to the CuRE1 bearing allele in the resistant strain, is found throughout Sub-Saharan Africa, in contrast to the diversity encountered in non-CuRE1 alleles. This suggests a single origin and subsequent spread due to selective advantage. CuRE1 is detectable using a simple diagnostic. When applied to Cx. quinquefasciatus larvae from Ghana we have demonstrated a significant association with permethrin resistance in multiple field sites (mean Odds Ratio = 3.86) suggesting this marker has relevance to natural populations of vector mosquitoes. However, when CuRE1 was excised from the allele used in the reporter assay through fusion PCR, expression was unaffected, indicating that the TE has no direct role in resistance and hence that CuRE1 is acting only as a marker of an as yet unidentified regulatory motif in the association analysis. This suggests that a re-evaluation of the assumption that TEs contribute regulatory motifs involved in gene expression may be necessary. 3 IntroductionThe control of a number of pernicious mosquito-borne diseases such as malaria, lymphatic filariasis Chanda et al., 2011;Himeidan et al., 2011; Mathias et al., 2011; Yewhalaw et al., 2011). Given that many resistance mutations are thought to be recessive in expression, development of DNA diagnostics enables disease and agricultural control programmes to identify resistance mechanisms when they are at low frequency and take ameliorating action before they cause economic or health impacts (Hemingway, 2009;Kelly-Hope et al., 2008). As shown in a number of recent studies, resistance alleles can rise towards fixation very rapidly (García et al., 2009;L...

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Section: Association Of the Mite Insertion Upstream Of Cyp9m10 With Pmentioning

confidence: 85%

Section: Gene Expression and Sequencing Of Cyp9m10 And Cyp4h34mentioning

confidence: 98%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

A cis-regulatory sequence driving metabolic insecticide resistance in mosquitoes: Functional characterisation and signatures of selection

Wilding

Smith

Lynd

et al. 2012

Insect Biochemistry and Molecular Biology

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“…So far, all other described P450s associated with insecticide resistance are expressed in susceptible insects and overexpressed in resistant insects (16,17,29,30,39,41,42,44,45,(52)(53)(54)(55)(56)(57). Overexpression can be caused by trans-(52) or cis-acting factors, the latter often associated with transposable element insertion in the promoter region (53,58,59). In a few cases, the expression is enhanced by an additional duplication of the P450 gene (58)(59)(60)(61)(62).…”

Section: Discussionmentioning

confidence: 99%

Resistance of AustralianHelicoverpa armigerato fenvalerate is due to the chimeric P450 enzyme CYP337B3

Joußen¹,

Agnolet

Lorenz

et al. 2012

Proc. Natl. Acad. Sci. U.S.A.

177

190

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Worldwide, increasing numbers of insects have evolved resistance to a wide range of pesticides, which hampers their control in the field and, therefore, threatens agriculture. Members of the carboxylesterase and cytochrome P450 monooxygenase superfamilies are prominent candidates to confer metabolic resistance to pyrethroid insecticides. Both carboxylesterases and P450 enzymes have been shown to be involved in pyrethroid resistance in Australian Helicoverpa armigera, the noctuid species possessing by far the most reported resistance cases worldwide. However, specific enzymes responsible for pyrethroid resistance in field populations of this species have not yet been identified. Here, we show that the resistance toward fenvalerate in an Australian strain of H. armigera is due to a unique P450 enzyme, CYP337B3, which arose from unequal crossing-over between two parental P450 genes, resulting in a chimeric enzyme. CYP337B3 is capable of metabolizing fenvalerate into 4′-hydroxyfenvalerate, which exhibits no toxic effect on susceptible larvae; enzymes from the parental P450 genes showed no detectable fenvalerate metabolism. Furthermore, a polymorphic H. armigera strain could be bred into a susceptible line possessing the parental genes CYP337B1 and CYP337B2 and a resistant line possessing only CYP337B3. The exclusive presence of CYP337B3 in resistant insects of this strain confers a 42-fold resistance to fenvalerate. Thus, in addition to previously documented genetic mechanisms of resistance, recombination can also generate selectively advantageous variants, such as this chimeric P450 enzyme with an altered substrate specificity leading to a potent resistance mechanism.pest management | cotton bollworm O ne of the main threats of agriculture nowadays is the rapid development of resistance of pest insect species to control agents worldwide. The cotton bollworm, Helicoverpa armigera (Hübner), is the noctuid species possessing by far the most reported cases of insecticide resistance worldwide with evolved resistance against pyrethroids, organophosphates, carbamates, organochlorines (www.pesticideresistance.org), and recently against the macrocyclic lactone spinosad (1) and Bacillus thuringiensis-derived toxins (2). This capacity is partly due to its distribution, which is one of the widest for any agricultural insect pest species, covering Africa, the Middle East, southern Europe, India, central and southeastern Asia, eastern and northern Australia, New Zealand, and many eastern Pacific Islands (3). In addition, H. armigera is a significant pest of cotton, the single crop most intensively sprayed with insecticides. Almost 30% of all pesticides used worldwide are directed against this insect pest (4). In Australia, the economic losses due to direct yield reduction and pest management of H. armigera and endemic H. punctigera were estimated to be approximately A$150 million in 1990-1991 (5). In addition, H. armigera is highly polyphagous, feeding on 72 known host plant species distributed in 29 families in Australia (6).Af...

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“…A constitutive overtranscription can be the consequence of an up-regulation controlled by cis/trans genomic regulatory elements or an increased gene copy number . Although gene amplifications have been associated with the overtranscription of a few pyrethroid resistance genes in mosquitoes (Wondji et al 2009;Itokawa et al 2010Itokawa et al , 2011Bariami et al 2012), no comprehensive screening of gene amplifications linked to insecticide resistance has ever been conducted. Considering the central role of copy number variation (CNV) in adaptations associated with a "gene dosage" effect (for review, see Kondrashov 2012) and the richness of the Ae.…”

mentioning

confidence: 99%

Identifying genomic changes associated with insecticide resistance in the dengue mosquito Aedes aegypti by deep targeted sequencing

et al. 2015

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The capacity of mosquitoes to resist insecticides threatens the control of diseases such as dengue and malaria. Until alternative control tools are implemented, characterizing resistance mechanisms is crucial for managing resistance in natural populations. Insecticide biodegradation by detoxification enzymes is a common resistance mechanism; however, the genomic changes underlying this mechanism have rarely been identified, precluding individual resistance genotyping. In particular, the role of copy number variations (CNVs) and polymorphisms of detoxification enzymes have never been investigated at the genome level, although they can represent robust markers of metabolic resistance. In this context, we combined target enrichment with high-throughput sequencing for conducting the first comprehensive screening of gene amplifications and polymorphisms associated with insecticide resistance in mosquitoes. More than 760 candidate genes were captured and deep sequenced in several populations of the dengue mosquito Ae. aegypti displaying distinct genetic backgrounds and contrasted resistance levels to the insecticide deltamethrin. CNV analysis identified 41 gene amplifications associated with resistance, most affecting cytochrome P450s overtranscribed in resistant populations. Polymorphism analysis detected more than 30,000 variants and strong selection footprints in specific genomic regions. Combining Bayesian and allele frequency filtering approaches identified 55 nonsynonymous variants strongly associated with resistance. Both CNVs and polymorphisms were conserved within regions but differed across continents, confirming that genomic changes underlying metabolic resistance to insecticides are not universal. By identifying novel DNA markers of insecticide resistance, this study opens the way for tracking down metabolic changes developed by mosquitoes to resist insecticides within and among populations.

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Cis-acting mutation and duplication: History of molecular evolution in a P450 haplotype responsible for insecticide resistance in Culex quinquefasciatus

Cited by 36 publications

References 48 publications

A cis-regulatory sequence driving metabolic insecticide resistance in mosquitoes: Functional characterisation and signatures of selection

A cis-regulatory sequence driving metabolic insecticide resistance in mosquitoes: Functional characterisation and signatures of selection

Resistance of AustralianHelicoverpa armigerato fenvalerate is due to the chimeric P450 enzyme CYP337B3

Identifying genomic changes associated with insecticide resistance in the dengue mosquito Aedes aegypti by deep targeted sequencing

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