Identification of novel Bacillus thuringiensis Cry1Ac binding proteins in Manduca sexta midgut through proteomic analysis

McNall, Rebecca J.; Adang, Michael J.

doi:10.1016/s0965-1748(03)00114-0

Cited by 155 publications

(157 citation statements)

References 27 publications

Supporting

Mentioning

147

Contrasting

Unclassified

Order By: Relevance

“…Similarly it was also reported that the ALP expression was significantly reduced in Cry1 resistance in insects (Jurat-Fuentes & Adang, 2004;Jurat-Fuentes et al, 2011;Flores-Escobar et al, 2013). In addition, ALPs have also been observed to bind a number of Cry toxins (Jiménez et al, 2012), as in Manduca sexta, Heliothis virescens and Spodoptera frugiperda (McNall & Adang, 2003;Jurat-Fuentes & Adang, 2004;Flores-Escobar et al, 2013).…”

Section: Resultsmentioning

confidence: 99%

Synergistic effect of certain insecticides combined with Bacillus thuringiensis on mosquito larvae

Narkhede

Suryawanshi

Koli

et al. 2017

J Entomol Acarol Res

View full text Add to dashboard Cite

For effective vector control it is essential to formulate new preparations having multiple action against the vector pest. Developing combined formulation of biopesticide and chemical pesticide is one of the novel concept to fight against the vectors with new weapons; however, compatibility of biopesticide i.e. Bacillus thuringiensis (Bt) and chemical pesticide is a real hurdle. In this investigation, local isolate Bacillus thuringiensis SV2 (BtSV2) was tested for its compatibility with various available mosquito larvicides. Temephos was most compatible with BtSV2 than with other tested pesticides. These two compatible agents were tested for larvicidal potential. Our study revealed that the synergistic effect of both agents reduces LC50 value by 30.68 and 22.36% against the Ae. aegypti and An. stephensi, respectively. The larvicidal potential increased when compared to individual pesticides. It was also observed a biochemical change in larvae after the TBT (Temephos + Bacillus thuringiensis) combination treatment; it involves decreased level of alpha esterase, acetylcholine esterase and protein while level of beta esterase and acid phosphatase was unchanged and alkaline phosphatase activity was increased. Increased potential of combined formulation may be due to altered physiological condition.

show abstract

Section: Resultsmentioning

confidence: 99%

Synergistic effect of certain insecticides combined with Bacillus thuringiensis on mosquito larvae

Narkhede

Suryawanshi

Koli

et al. 2017

J Entomol Acarol Res

View full text Add to dashboard Cite

show abstract

“…Fig. 1A shows that Cry1Ab bound preferentially to a 65-kDa protein, previously identified as ALP (25) in BBMV isolated from first and second instar larvae. In contrast, these assays revealed that at the latter stages of larval development, such as the fourth and fifth instar, only the 120-kDa corresponding to APN protein but not the 65-kDa band was observed.…”

Section: Expression Of Aminopeptidase and Alkaline Phosphatase Proteimentioning

confidence: 92%

“…These apparently contradictory data could be explained if an additional secondary receptor could play the same role as APN in M. sexta midgut cells. In this regard, a GPI-anchored ALP was also identified as a binding protein of Cry1Ac toxin in M. sexta, although its role as a Cry1A receptor has not been analyzed until now (25,26).…”

mentioning

confidence: 99%

Role of Alkaline Phosphatase from Manduca sexta in the Mechanism of Action of Bacillus thuringiensis Cry1Ab Toxin

Arenas

Bravo

Soberón

et al. 2010

Journal of Biological Chemistry

154

157

View full text Add to dashboard Cite

Cry toxins produced by Bacillus thuringiensis have been recognized as pore-forming toxins whose primary action is to lyse midgut epithelial cells in their target insect. In the case of the Cry1A toxins, a prepore oligomeric intermediate is formed after interaction with cadherin receptor. The Cry1A oligomer then interacts with glycosylphosphatidylinositol-anchored receptors. Two Manduca sexta glycosylphosphatidylinositol-anchored proteins, aminopeptidase (APN) and alkaline phosphatase (ALP), have been shown to bind Cry1Ab, although their role in toxicity remains to be determined. Detection of Cry1Ab binding proteins by ligand blot assay revealed that ALP is preferentially expressed earlier during insect development, because it was found in the first larval instars, whereas APN is induced later after the third larval instar. The binding of Cry1Ab oligomer to pure preparations of APN and ALP showed that this toxin structure interacts with both receptors with high affinity (apparent K d ‫؍‬ 0.6 nM), whereas the monomer showed weaker binding (apparent K d ‫؍‬ 101.6 and 267.3 nM for APN and ALP, respectively). Several Cry1Ab nontoxic mutants located in the exposed loop 2 of domain II or in ␤-16 of domain III were affected in binding to APN and ALP, depending on their oligomeric state. In particular monomers of the nontoxic domain III, the L511A mutant did not bind ALP but retained APN binding, suggesting that initial interaction with ALP is critical for toxicity. Our data suggest that APN and ALP fulfill two roles. First APN and ALP are initial receptors promoting the localization of toxin monomers in the midgut microvilli before interaction with cadherin. Then APN and ALP function as secondary receptors mediating oligomer insertion into the membrane. However, the expression pattern of these receptors and the phenotype of L511A mutant suggest that ALP may have a predominant role in toxin action because Cry toxins are highly effective against the neonate larvae that is the target for pest control programs.The Cry toxins produced by Bacillus thuringiensis are used worldwide as effective biological control agents for many species of insects including agricultural and forest pests and several vectors of human and animal diseases. Its insecticidal property results from crystalline inclusions produced during sporulation that are formed by ␦-endotoxins known as Cry toxins (1).The Cry protein family is composed of more than 54 groups, among which the three-domain Cry family forms the major group, having members that show toxicity to different insect orders and to nematodes. The crystal structure has been solved for six three-domain Cry toxins and one protoxin that display different insect specificities (2). The activated Cry toxins are globular molecules consisting of a bundle of seven ␣-helices (domain I), a three-␤-sheet prism (domain II), and a ␤-sandwich (domain III) (3, 4). The N-terminal domain I is involved in oligomer formation, membrane insertion, and pore formation (5-8). Domain II and III are involved in the recogn...

show abstract

“…These new approaches are particularly well illustrated by recent advances in our understanding of Bt resistance in Lepidoptera. For example, although numerous potential Cry1Ac-binding proteins have been identified from the brush border membrane of the lepidopteran midgut (Vadlamudi et al 1995;Nagamatsu et al 1998;McNall and Adang 2003), only one potential receptor, a 12-cadherin domain protein, has been linked to various resistant strains of the different caterpillar pests Heliothis virescens (Gahan et al 2001), Pectinophora gossypiella (Morin et al 2003), and Helicoverpa armigera (Xu et al 2005). This situation has now changed dramatically following the mapping of a second Cry1Ac resistance locus in H. virescens encoding the ABC transporter C2 (Gahan et al 2010).…”

Section: New Targets and New Methodsmentioning

confidence: 99%

The Molecular Genetics of Insecticide Resistance

2013

View full text Add to dashboard Cite

The past 60 years have seen a revolution in our understanding of the molecular genetics of insecticide resistance. While at first the field was split by arguments about the relative importance of mono-vs. polygenic resistance and field-vs. laboratory-based selection, the application of molecular cloning to insecticide targets and to the metabolic enzymes that degrade insecticides before they reach those targets has brought out an exponential growth in our understanding of the mutations involved. Molecular analysis has confirmed the relative importance of single major genes in target-site resistance and has also revealed some interesting surprises about the multi-gene families, such as cytochrome P450s, involved in metabolic resistance. Identification of the mutations involved in resistance has also led to parallel advances in our understanding of the enzymes and receptors involved, often with implications for the role of these receptors in humans. This Review seeks to provide an historical perspective on the impact of molecular biology on our understanding of resistance and to begin to look forward to the likely impact of rapid advances in both sequencing and genome-wide association analysis."Curiouser and curiouser!" cried Alice.Lewis Carroll L ewis Carroll sent Alice down a rabbit hole without the least idea of what was to happen next, but as Alice ventured deeper into Wonderland things became "Curiouser and curiouser!" So indeed have studies on the molecular basis of insecticide resistance. While starting with rather simplistic expectations about the role of single mutations in single genes, resistance has been shown to involve a panoply of multiple mutations in multiple genes, often with independent and complex origins. This review will attempt to place these current findings into context and to examine the extent to which the field has often been historically blindsided by dogma. My arguments will encompass key controversies debated in the field such as the relative importance of mono-vs. polygenic resistance and the implications of resistance-associated mutations for whole-organism fitness in the absence of pesticide. Importantly, we will also examine the role of dogma in shaping the way that resistance research has been pursued over the past 50 years. Key questions addressed are therefore: How many mutations per gene cause resistance? How many mechanisms are there per species (genome)? How many independent genetic origins (mutations) give rise to each mechanism? What new mechanisms are still undiscovered and how might they arise? Monogenic vs. Polygenic ResistanceCrow, DDT, and DrosophilaThe humble fruit fly Drosophila melanogaster has been a key tool in unlocking the molecular basis of insecticide resistance, and early studies by James Crow and others have helped to establish Drosophila as a genetic model for resistance studies. Studies of DDT resistance in Drosophila have also typified arguments surrounding mono-vs. polygenic inheritance of insecticide resistance. In his pioneering review of in...

show abstract

Identification of novel Bacillus thuringiensis Cry1Ac binding proteins in Manduca sexta midgut through proteomic analysis

Cited by 155 publications

References 27 publications

Synergistic effect of certain insecticides combined with Bacillus thuringiensis on mosquito larvae

Synergistic effect of certain insecticides combined with Bacillus thuringiensis on mosquito larvae

Role of Alkaline Phosphatase from Manduca sexta in the Mechanism of Action of Bacillus thuringiensis Cry1Ab Toxin

The Molecular Genetics of Insecticide Resistance

Contact Info

Product

Resources

About