scholarly journals Transposon-mediated insertional mutagenesis unmasks recessive insecticide resistance in the aphid Myzus persicae

2021 ◽  
Vol 118 (23) ◽  
pp. e2100559118
Author(s):  
Michela Panini ◽  
Olga Chiesa ◽  
Bartlomiej J. Troczka ◽  
Mark Mallott ◽  
Gian Carlo Manicardi ◽  
...  
Keyword(s):  
Insecticide Resistance ◽  
Myzus Persicae ◽  
Genetic Variants ◽  
Insertional Mutagenesis ◽  
Phenotypic Expression ◽  
Monoallelic Expression ◽  
Resistance Mutations ◽  
Evolutionary Potential ◽  
Resistant Allele ◽  
Susceptible Allele

The evolution of resistance to insecticides threatens the sustainable control of many of the world’s most damaging insect crop pests and disease vectors. To effectively combat resistance, it is important to understand its underlying genetic architecture, including the type and number of genetic variants affecting resistance and their interactions with each other and the environment. While significant progress has been made in characterizing the individual genes or mutations leading to resistance, our understanding of how genetic variants interact to influence its phenotypic expression remains poor. Here, we uncover a mechanism of insecticide resistance resulting from transposon-mediated insertional mutagenesis of a genetically dominant but insecticide-susceptible allele that enables the adaptive potential of a previously unavailable recessive resistance allele to be unlocked. Specifically, we identify clones of the aphid pest Myzus persicae that carry a resistant allele of the essential voltage-gated sodium channel (VGSC) gene with the recessive M918T and L1014F resistance mutations, in combination with an allele lacking these mutations but carrying a Mutator-like element transposon insertion that disrupts the coding sequence of the VGSC. This results in the down-regulation of the dominant susceptible allele and monoallelic expression of the recessive resistant allele, rendering the clones resistant to the insecticide bifenthrin. These findings are a powerful example of how transposable elements can provide a source of evolutionary potential that can be revealed by environmental and genetic perturbation, with applied implications for the control of highly damaging insect pests.

Incidence of insecticide resistance alleles in sexually-reproducing populations of the peach–potato aphid Myzus persicae (Hemiptera: Aphididae) from southern France

2003 ◽  
Vol 93 (4) ◽  
pp. 289-297 ◽  
Author(s):  
T. Guillemaud ◽  
A. Brun ◽  
N. Anthony ◽  
M.H. Sauge ◽  
R. Boll ◽  
...  
Keyword(s):  
Insecticide Resistance ◽  
Myzus Persicae ◽  
Resistance Mechanisms ◽  
Resistance Mutations ◽  
Potato Aphid ◽  
Southern France ◽  
Chemical Treatments ◽  
Before And After ◽  
Almost All ◽  
Peach Potato Aphid

AbstractIntensive chemical treatments have led to the development of a number of insecticide resistance mechanisms in the peach–potato aphid Myzus persicae (Sulzer). Some of these mechanisms are known to be associated with negative pleiotropic effects (resistance costs). Molecular and biochemical methods were used to determine the genotypes or phenotypes associated with four insecticide resistance mechanisms in single aphids from sexually-reproducing populations in southern France. The mechanisms considered were E4 and FE4 carboxylesterase overproduction, modified acetycholinesterase, and kdr and rdl resistance-associated mutations. A new method for determining individual kdr genotypes is presented. Almost all resistant individuals overproduced FE4 carboxylesterase, whereas modified acetylcholinesterase was rare. Both the kdr and rdl resistance mutations were present at high frequencies in French sexually-reproducing populations. The frequencies of insecticide resistance genes were compared before and after sexual reproduction in one peach orchard at Avignon to evaluate the potential impact of selection on the persistence of resistance alleles in the over-wintering phase. The frequencies of the kdr and rdl mutations varied significantly between autumn and spring sampling periods. The frequency of the kdr mutation increased, probably due to pyrethroid treatments at the end of the winter. Conversely, the frequency of the rdl mutation decreased significantly during winter, probably because of a fitness cost associated with this mutation.

Changes in the genetic composition of Myzus persicae nicotianae populations in Chile and frequency of insecticide resistance mutations

2021 ◽  
pp. 1-9
Author(s):  
Marco A. Cabrera-Brandt ◽  
Amalia Kati ◽  
María E. Rubio-Meléndez ◽  
Christian C. Figueroa ◽  
Eduardo Fuentes-Contreras
Keyword(s):  
Insecticide Resistance ◽  
Myzus Persicae ◽  
Agricultural Practices ◽  
Future Research ◽  
Agricultural Pest ◽  
Genetic Composition ◽  
Resistance Mutations ◽  
Tobacco Cultivation ◽  
Insight Into ◽  
Entire Distribution

Abstract Myzus persicae is a cosmopolitan aphid that is highly polyphagous and an important agricultural pest. The subspecies M. persicae nicotianae has been described for highly specialized phenotypes adapted to tobacco (Nicotiana tabacum). In Chile, the population of M. persicae nicotianae was originally composed of a single red genotype that did not possess insecticide resistance mutations. However, in the last decade, variation in the colour of tobacco aphids has been observed in the field. To determine whether this variation stems from the presence of new genotypes, sampling was carried out across the entire distribution of tobacco cultivation regions in Chile. The aphids collected were genotyped, and the frequency of kdr (L1014F), super-kdr (M918T), modification of acetylcholinesterase (MACE) and nicotinic acetylcholine receptor β subunit (nAChRβ) mutations associated with insecticide resistance was determined. A total of 16 new genotypes of M. persicae nicotianae were detected in Chile: four of them possessed the MACE mutation, and none of them possessed the kdr, super-kdr or nAChRβ mutation. The previously described red genotype was not detected in any of the sampled fields over two seasons. These results raise questions about the mechanisms underlying changes in the genetic structure of M. persicae nicotianae populations in Chile. Future research aimed at addressing these questions could provide new insight into aphid evolution and agricultural practices.

scholarly journals Neurodevelopmental Trajectories and Psychiatric Morbidity: Lessons Learned From the 22q11.2 Deletion Syndrome

2021 ◽  
Vol 23 (3) ◽  
Author(s):  
Ania M. Fiksinski ◽  
Maude Schneider ◽  
Janneke Zinkstok ◽  
Danielle Baribeau ◽  
Samuel J. R. A. Chawner ◽  
...  
Keyword(s):  
Genetic Variants ◽  
Clinical Care ◽  
Psychiatric Morbidity ◽  
Phenotypic Expression ◽  
22Q11.2 Deletion Syndrome ◽  
Autism Spectrum ◽  
Lessons Learned ◽  
Deletion Syndrome ◽  
22Q11.2 Deletion ◽  
Variable Expression

AbstractPurpose of ReviewThe 22q11.2 deletion syndrome (22q11DS) is associated with a broad spectrum of neurodevelopmental phenotypes and is the strongest known single genetic risk factor for schizophrenia. Compared to other rare structural pathogenic genetic variants, 22q11DS is relatively common and one of the most extensively studied. This review provides a state-of-the-art overview of current insights regarding associated neurodevelopmental phenotypes and potential implications for 22q11DS and beyond.Recent FindingsWe will first discuss recent findings with respect to neurodevelopmental phenotypic expression associated with 22q11DS, including psychotic disorders, intellectual functioning, autism spectrum disorders, as well as their interactions. Second, we will address considerations that are important in interpreting these data and propose potential implications for both the clinical care for and the empirical study of individuals with 22q11DS. Third, we will highlight variable penetrance and pleiotropy with respect to neurodevelopmental phenotypes in 22q11DS. We will discuss how these phenomena are consistently observed in the context of virtually all rare pathogenic variants and that they pose substantial challenges from both a clinical and a research perspective.SummaryWe outline how 22q11DS could be viewed as a genetic model for studying neurodevelopmental phenotypes. In addition, we propose that 22q11DS research can help elucidate mechanisms underlying variable expression and pleiotropy of neurodevelopmental phenotypes, insights that are likely relevant for 22q11DS and beyond, including for individuals with other rare pathogenic genetic variants and for individuals with idiopathic neurodevelopmental conditions.

scholarly journals Global patterns in genomic diversity underpinning the evolution of insecticide resistance in the aphid crop pest Myzus persicae

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Kumar Saurabh Singh ◽  
Erick M. G. Cordeiro ◽  
Bartlomiej J. Troczka ◽  
Adam Pym ◽  
Joanna Mackisack ◽  
...  
Keyword(s):  
Host Plant ◽  
Myzus Persicae ◽  
Resistance Mechanisms ◽  
Genomic Diversity ◽  
Resistance Mutations ◽  
Host Plant Adaptation ◽  
Repeated Evolution ◽  
Evolution Of Resistance ◽  
Selective Forces ◽  
Clonal Lines

AbstractThe aphid Myzus persicae is a destructive agricultural pest that displays an exceptional ability to develop resistance to both natural and synthetic insecticides. To investigate the evolution of resistance in this species we generated a chromosome-scale genome assembly and living panel of >110 fully sequenced globally sampled clonal lines. Our analyses reveal a remarkable diversity of resistance mutations segregating in global populations of M. persicae. We show that the emergence and spread of these mechanisms is influenced by host–plant associations, uncovering the widespread co‐option of a host-plant adaptation that also offers resistance against synthetic insecticides. We identify both the repeated evolution of independent resistance mutations at the same locus, and multiple instances of the evolution of novel resistance mechanisms against key insecticides. Our findings provide fundamental insights into the genomic responses of global insect populations to strong selective forces, and hold practical relevance for the control of pests and parasites.

scholarly journals The properties of a carboxylesterase from the peach-potato aphid, Myzus persicae (Sulz.), and its role in conferring insecticide resistance

1977 ◽  
Vol 167 (3) ◽  
pp. 675-683 ◽  
Author(s):  
Alan L. Devonshire
Keyword(s):  
Insecticide Resistance ◽  
Myzus Persicae ◽  
Order Rate Constant ◽  
Preliminary Evidence ◽  
Exchange Chromatography ◽  
Potato Aphid ◽  
First Order ◽  
Different Strains ◽  
Hydrolysis Of ◽  
Peach Potato Aphid

Carboxylesterases from different strains of Myzus persicae were examined to try to understand their contribution to insecticide resistance. Preliminary evidence that they are involved comes from the good correlation between the degree of resistance and the carboxylesterase and paraoxon-degrading activity in aphid homogenates. Furthermore the carboxylesterase associated with resistance could not be separated from the insecticide-degrading enzyme by electrophoresis or ion-exchange chromatography. Homogenates of resistant aphids hydrolysed paraoxon 60 times faster than did those of susceptible aphids, yet the purified enzymes from both sources had identical catalytic-centre activities towards this substrate and also towards naphth-1-yl acetate, the latter being hydrolysed by both 2×106 times faster than paraoxon. These observations provide evidence that the enzyme from both sources is identical, and that one enzyme hydrolyses both substrates. This was confirmed by relating the rate of paraoxon hydrolysis to the rate at which paraoxon-inhibited carboxylesterase re-activated. Both had the same first-order rate constant (0.01min−1), showing clearly that the hydrolysis of both substrates is brought about by the same enzyme. Its Km for naphth-1-yl acetate was 0.131mm, and for paraoxon 75pm. The latter very small value could not be measured directly, but was calculated from substrate-competition studies coupled with measurements of re-activation of the diethyl phosphorylated enzyme. Since the purified enzymes from resistant and susceptible aphids had the same catalytic-centre activity, the 60-fold difference between strains must be caused by different amounts of the same enzyme resulting from mutations of the regulator gene(s) rather than of the structural gene.

Sign in / Sign up

Export Citation Format

Share Document