Read by QxMD icon Read

receptors lepidoptera bacillus thuringiensis

Andresa C B Oliveira, Valeria Wanderley-Teixeira, Cristiane T S Silva, Álvaro A C Teixeira, Herbert A A Siqueira, Glauciane S Cruz, Clovis L Neto, Amanda L R Lima, Maria T S Correia
BACKGROUND: Studies show that insects can adapt to the toxins of Bacillus thuringiensis in field and laboratory conditions through the development of resistance to this bacterium and its formulations. This has been demonstrated in the failure to control Tuta absoluta populations in Brazil. This study evaluated membrane receptors using peroxidase labelled lectins and the midgut histochemistry of T. absoluta populations in order to assess susceptibility to the insecticides Dipel® and XenTari® ...
April 26, 2018: Pest Management Science
Junxiang Wang, Guifang Lin, Khadija Batool, Shuaiqi Zhang, Mingfeng Chen, Jin Xu, Juan Wu, Liang Jin, Ivan Gelbic, Lei Xu, Lingling Zhang, Xiong Guan
Ectropis oblique Prout (Lepidoptera: Geometridae) is one of the main pests that damages the tea crop in Southeast Asia. To understand the molecular mechanisms of its feeding biology, transcriptomes of the alimentary tract (AT) and of the body minus the AT of E. oblique were successfully sequenced and analyzed in this study. A total of 36,950 unigenes from de novo sequences were assembled. After analysis using six annotation databases (e.g., Gene Ontology, Kyoto Encyclopedia of Genes and Genome, and NCBI nr), a series of putative genes were found for this insect species that were related to digestion, detoxification, the immune system, and Bacillus thuringiensis (Bt) receptors...
March 12, 2018: Journal of Economic Entomology
Xiaodan Hu, Xiao Zhang, Jianfeng Zhong, Yuan Liu, Cunzheng Zhang, Yajing Xie, Manman Lin, Chongxin Xu, Lina Lu, Qing Zhu, Xianjin Liu
Cadherin-like protein has been identified as the primary Bacillus thuringiensis (Bt) Cry toxin receptor in Lepidoptera pests and plays a key role in Cry toxin insecticidal. In this study, we successfully expressed the putative Cry1Ac toxin-binding region (CR7-CR11) of Plutella xylostella cadherin-like in Escherichia coli BL21 (DE3). The expressed CR7-CR11 fragment showed binding ability to Cry1Ac toxin under denaturing (Ligand blot) and non-denaturing (ELISA) conditions. The three-dimensional structure of CR7-CR11 was constructed by homology modeling...
May 2018: International Journal of Biological Macromolecules
Tiantao Zhang, Brad S Coates, Yueqin Wang, Yidong Wang, Shuxiong Bai, Zhenying Wang, Kanglai He
The Asian corn borer (ACB), Ostrinia furnacalis (Lepidoptera: Crambidae), is a highly destructive pest of cultivated maize throughout East Asia. Bacillus thuringiensis (Bt) crystalline protein (Cry) toxins cause mortality by a mechanism involving pore formation or signal transduction following toxin binding to receptors along the midgut lumen of susceptible insects, but this mechanism and mutations therein that lead to resistance are not fully understood. In the current study, quantitative comparisons were made among midgut expressed transcripts from O...
2017: International Journal of Biological Sciences
Hanen Boukedi, Saoussen Ben Khedher, Rania Hadhri, Samir Jaoua, Slim Tounsi, Lobna Abdelkefi-Mesrati
Bacillus thuringiensis strain BLB459 supernatant showed a promising activity against Lepidopteran pests with extremely damages in the larvae midgut. Investigations of the genes that encode secreted toxin demonstrated that this strain harbored a vip3-type gene named vip3(459). Based on its original nucleotide and amino acid sequences, this gene was cloned into pET-14b vector and overexpressed in Escherichia coli. The expressed protein was purified and tested against different insects and interestingly the novel toxin demonstrated a remarkable activity against the stored products pest Ephestia kuehniella and the polyphagous insects Spodoptera littoralis and Agrotis segetum...
April 2017: Toxicon: Official Journal of the International Society on Toxinology
Shu Yinghua, Du Yan, Chen Jin, Wei Jiaxi, Wang Jianwu
To examine the responses of the secondary lepidopteran pest Spodoptera litura to two Bacillus thuringiensis (Bt) corn hybrids [5422Bt1 (Event Bt11), 5422CBCL (MON810)] expressing Cry1Ab, larval bioassays with Cry1Ab toxin, corn leaves or kernels and bagging on corn plants were conducted. The results showed that larvae displayed a similar performance when fed kernels, but not leaves of 5422Bt1, 5422CBCL and their near-isogenic non-Bt corn (5422). Significantly higher Cry1Ab amounts were detected in larvae fed leaves than kernels of both Bt hybrids, with different molecular weights of protein band in plants (72 and 90 kDa for 5422Bt1 and 5422CBCL, respectively), gut contents (65 kDa), feces (50 kDa), which indicated that larvae had lower ingestion, higher degradation and excretion of Cry1Ab when fed kernels not leaves of both Bt hybrids...
February 10, 2017: Scientific Reports
Yannick Pauchet, Anne Bretschneider, Sylvie Augustin, David G Heckel
Chrysomela tremula is a polyvoltine oligophagous leaf beetle responsible for massive attacks on poplar trees. This beetle is an important model for understanding mechanisms of resistance to Bacillus thuringiensis (Bt) insecticidal toxins, because a resistant C. tremula strain has been found that can survive and reproduce on transgenic poplar trees expressing high levels of the Cry3Aa Bt toxin. Resistance to Cry3Aa in this strain is recessive and is controlled by a single autosomal locus. We used a larval midgut transcriptome for C...
December 5, 2016: Toxins
Anne Bretschneider, David G Heckel, Yannick Pauchet
Insecticidal crystal (Cry) proteins from Bacillus thuringiensis (Bt) are highly active against Lepidoptera. However, field-evolved resistance to Bt toxins is on the rise. The 12-cadherin domain protein HevCaLP and the ABC transporter HevABCC2 are both genetically linked to Cry toxin resistance in Heliothis virescens. We investigated their interaction using stably expressing non-lytic clonal Sf9 cell lines expressing either protein or both together. Untransfected Sf9 cells are innately sensitive to Cry1Ca toxin, but not to Cry1A toxins; and quantitative PCR revealed negligible expression of genes involved in Cry1A toxicity such as cadherin, ABCC2, alkaline phosphatase (ALP) and aminopeptidase N (APN)...
September 2016: Insect Biochemistry and Molecular Biology
Brad S Coates
Transgenic plants that express Bacillus thuringiensis (Bt) crystal (Cry) protein toxins (Bt crops) effectively control feeding by the European corn borer, Ostrinia nubilalis, although documented resistance evolution among a number of species in both the laboratory and field has heightened concerns about the durability of this technology. Research has provided major insights into the mutations that alter Bt toxin binding receptor structure and function within the midgut of Lepidoptera that directly impacts the efficacy of Bt toxins, and potentially leads to the evolution of resistance to Bt crops in the field...
June 2016: Current Opinion in Insect Science
Erica E Tassone, Gina Zastrow-Hayes, John Mathis, Mark E Nelson, Gusui Wu, J Lindsey Flexner, Yves Carrière, Bruce E Tabashnik, Jeffrey A Fabrick
BACKGROUND: The pink bollworm Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae) is one of the world's most important pests of cotton. Insecticide sprays and transgenic cotton producing toxins of the bacterium Bacillus thuringiensis (Bt) are currently used to manage this pest. Bt toxins kill susceptible insects by specifically binding to and destroying midgut cells, but they are not toxic to most other organisms. Pink bollworm is useful as a model for understanding insect responses to Bt toxins, yet advances in understanding at the molecular level have been limited because basic genomic information is lacking for this cosmopolitan pest...
June 22, 2016: GigaScience
Dandan Zhang, Yutao Xiao, Khalid Hussain Dhiloo, Mario Soberon, Alejandra Bravo, Kongming Wu
Glycosphingolipids (GSLs) play important roles in the cellular biology of vertebrate and invertebrate organisms, such as cell differentiation, tumor metastasis, and cell coordination. GSLs also serve as receptors for different bacterial toxins. For example, in the nematode Caenorhabditis elegans, GSLs function as receptors of the insecticidal Cry toxins produced by Bacillus thuringiensis (Bt), and mutations in bre genes involved in GSLs synthesis resulted in resistance to Cry5 toxin in this organism. However, the information of GSLs function in insects is still limited...
May 17, 2016: Journal of Economic Entomology
Maissa Chakroun, Núria Banyuls, Yolanda Bel, Baltasar Escriche, Juan Ferré
Entomopathogenic bacteria produce insecticidal proteins that accumulate in inclusion bodies or parasporal crystals (such as the Cry and Cyt proteins) as well as insecticidal proteins that are secreted into the culture medium. Among the latter are the Vip proteins, which are divided into four families according to their amino acid identity. The Vip1 and Vip2 proteins act as binary toxins and are toxic to some members of the Coleoptera and Hemiptera. The Vip1 component is thought to bind to receptors in the membrane of the insect midgut, and the Vip2 component enters the cell, where it displays its ADP-ribosyltransferase activity against actin, preventing microfilament formation...
June 2016: Microbiology and Molecular Biology Reviews: MMBR
Guoying Han, Xiumin Li, Ting Zhang, Xiaoting Zhu, Jigang Li
Chitin deacetylases (CDAs) convert chitin into chitosan, the N-deacetylated form of chitin, which influences the mechanical and permeability properties of structures such as the cuticle and peritrophic matrices. In this article, a new CDA encoding gene, Hacda2, was cloned by reverse transcription-polymerase chain reaction method in Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae), with an open reading frame of 1,611 bp. The deduced protein composed of 536 amino acid residues with a signal peptide, a chitin-binding domain, a low-density lipoprotein receptor class A domain, and a polysaccharide deacetylase-like catalytic domain...
2015: Journal of Insect Science
Xun Zhu, Yanyuan Lei, Yanjv Yang, Simon W Baxter, Jianhong Li, Qingjun Wu, Shaoli Wang, Wen Xie, Zhaojiang Guo, Wei Fu, Youjun Zhang
BACKGROUND: Resistance to insecticidal Bacillus thuringiensis (Bt) toxins has arisen in multiple populations of the worldwide Brassica pest Plutella xylostella (L.). To help elucidate the mechanism of resistance to Bt Cry1Ac toxin in a population from Florida, two pairs of near-isogenic lines (NILs) were developed. RESULTS: NILs were generated using either backcross or recombinant inbred line methodologies and evaluated for near-isogenicity with inter-simple-sequence-repeat (ISSR) markers...
February 2015: Pest Management Science
Guangchun Cao, Lili Zhang, Gemei Liang, Xianchun Li, Kongming Wu
Development of resistance to transgenic crops expressing the Cry toxin from Bacterium thuringiensis (Bt) has been the major concern for the long-term success of Bt crops. Alterations in nonbinding site proteinases and Bt toxin receptors are the two types of mechanisms responsible for Bt resistance in resistant insects. However, little is known about the relative contributions of the two types of mechanisms in the early and late phases of the development of Bt resistance. To address the relative contributions of four nonbinding site proteinases including esterase, total protease, chymotrypsin, and glutathione S-transferase in the early and late phases of the development of Cry1Ac resistance, we analyzed the relationships between nonbinding site proteinases and resistance of three groups of Helicoverpa armigera Hübner (Lepidoptera: Noctuidae) strains with different resistance levels because of different geographic origins and selection pressures...
December 2013: Journal of Economic Entomology
Sunita Tajne, Dayakar Boddupally, Vijayakumar Sadumpati, Dashavantha Reddy Vudem, Venkateswara Rao Khareedu
Different transgenic crop plants, developed with δ-endotoxins of Bacillus thuringiensis (Bt) and mannose-specific plant lectins, exhibited significant protection against chewing and sucking insects. In the present study, a synthetic gene (cry-asal) encoding the fusion-protein having 488 amino acids, comprising DI and DII domains from Bt Cry1Ac and Allium sativum agglutinin (ASAL), was cloned and expressed in Escherichia coli. Ligand blot analysis disclosed that the fusion-protein could bind to more number of receptors of brush border membrane vesicle (BBMV) proteins of Helicoverpa armigera...
February 10, 2014: Journal of Biotechnology
Ping Lin, Tingcai Cheng, Shengkai Jin, Liang Jiang, Chen Wang, Qingyou Xia
Aminopeptidases N (APNs), the receptors of Bacillus thuringiensis (Bt) toxin in the lepidopteran midgut, are involved in the Bt pathogen infection mechanism. In the present work, we screened 102 APNs from SilkDB, ButterflyBase and MonarchBase; 16 APNs were identified from the silkworm (Bombyx mori) and 24 from the monarch butterfly (Danaus plexippus). Syntenic and phylogenetic tree analysis showed that APN genes have developed multi-family genes before evolutionary divergence of the Lepidoptera. The tissue-expression pattern shows some BmAPNs are specifically or highly expressed in the midgut...
February 10, 2014: Gene
Lidia Mariana Fiuza, Neiva Knaak, Rogério Fernando Pires da Silva, João Antônio Pêgas Henriques
Bioassays with insecticidal crystal proteins (ICPs) from Bacillus thuringiensis have demonstrated that Cry1Aa, Cry1Ac, and Cry1Ba are the most active toxins on larvae of the Anticarsia gemmatalis. The toxins Cry1Da and Cry1Ea are less toxic, and toxins Cry2Aa are not active. Binding of these ICPs to midgut sections of the A. gemmatalis larvae was studied using streptavidin-mediated detection. The observed staining patterns showed that Cry1Aa and Cry1Ac bound to the brush border throughout the whole length of the midgut...
2013: ISRN Microbiology
Blanca I García-Gómez, Jorge Sánchez, Diana L Martínez de Castro, Jorge E Ibarra, Alejandra Bravo, Mario Soberón
Bacillus thuringiensis Cry1AbMod toxins are engineered versions of Cry1Ab that lack the amino-terminal end, including domain I helix α-1 and part of helix α-2. This deletion improves oligomerization of these toxins in solution in the absence of cadherin receptor and counters resistance to Cry1A toxins in different lepidopteran insects, suggesting that oligomerization plays a major role in their toxicity. However, Cry1AbMod toxins are toxic to Escherichia coli cells, since the cry1A promoter that drives its expression in B...
November 2013: Applied and Environmental Microbiology
Sek Yee Tan, Bonifacio F Cayabyab, Edwin P Alcantara, Fangneng Huang, Kanglai He, Kenneth W Nickerson, Blair D Siegfried
The European (Ostrinia nubilalis Hübner) and Asian corn borers (Ostrinia furnacalis Guenée) are closely related and display similar sensitivity to Cry1 toxins. In this study, we compared the binding patterns of Cry1Ab and Cry1F toxins between both Ostrinia spp., as well as the expression of putative cadherin- and aminopeptidase-N (APN)-like protein receptors. Additionally, cDNA sequences of these putative toxin receptors from both Ostrinia species were compared. Ligand blots for both species indicated a similar binding pattern for Cry1Ab with the strongest immunoreactive band at 260 kDa in both species...
November 2013: Journal of Invertebrate Pathology
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"