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1.
Proc Natl Acad Sci U S A ; 121(28): e2402407121, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38959045

RESUMO

Trade-offs between evolutionary gain and loss are prevalent in nature, yet their genetic basis is not well resolved. The evolution of insect resistance to insecticide is often associated with strong fitness costs; however, how the fitness trade-offs operates remains poorly understood. Here, we show that the mitogen-activated protein kinase (MAPK) pathway and its upstream and downstream actors underlie the fitness trade-offs associated with insecticide resistance in the whitefly Bemisia tabaci. Specifically, we find a key cytochrome P450 gene CYP6CM1, that confers neonicotinoids resistance to in B. tabaci, is regulated by the MAPKs p38 and ERK through their activation of the transcription factor cAMP-response element binding protein. However, phosphorylation of p38 and ERK also leads to the activation of the transcription repressor Cap "n" collar isoform C (CncC) that negatively regulates exuperantia (Ex), vasa (Va), and benign gonial cell neoplasm (Bg), key genes involved in oogenesis, leading to abnormal ovary growth and a reduction in female fecundity. We further demonstrate that the transmembrane G protein-coupled receptor (GPCR) neuropeptide FF receptor 2 (NPFF2) triggers the p38 and ERK pathways via phosphorylation. Additionally, a positive feedback loop between p38 and NPFF2 leads to the continuous activation of the MAPK pathways, thereby constitutively promoting neonicotinoids resistance but with a significant reproductive cost. Collectively, these findings provide fundamental insights into the role of cis-trans regulatory networks incurred by GPCR-MAPK signaling pathways in evolutionary trade-offs and applied knowledge that can inform the development of strategies for the sustainable pest control.


Assuntos
Hemípteros , Proteínas de Insetos , Resistência a Inseticidas , Sistema de Sinalização das MAP Quinases , Receptores Acoplados a Proteínas G , Animais , Hemípteros/genética , Hemípteros/metabolismo , Resistência a Inseticidas/genética , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/genética , Proteínas de Insetos/metabolismo , Proteínas de Insetos/genética , Feminino , Inseticidas/farmacologia , Sistema Enzimático do Citocromo P-450/metabolismo , Sistema Enzimático do Citocromo P-450/genética
2.
Adv Sci (Weinh) ; 11(10): e2306653, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38145364

RESUMO

Polyunsaturated fatty acids (PUFAs) are essential nutrients for all living organisms. PUFA synthesis is mediated by Δ12 desaturases in plants and microorganisms, whereas animals usually obtain PUFAs through their diet. The whitefly Bemisia tabaci is an extremely polyphagous agricultural pest that feeds on phloem sap of many plants that do not always provide them with sufficient PUFAs. Here, a plant-derived Δ12 desaturase gene family BtFAD2 is characterized in B. tabaci and it shows that the BtFAD2-9 gene enables the pest to synthesize PUFAs, thereby significantly enhancing its fecundity. The role of BtFAD2-9 in reproduction is further confirmed by transferring the gene to Drosophila melanogaster, which also increases the fruit fly's reproduction. These findings reveal an extraordinary evolutionary scenario whereby a phytophagous insect acquired a family of plant genes that enables it to synthesize essential nutrients, thereby lessening its nutritional dependency and allowing it to feed and reproduce on many host plants.


Assuntos
Ácidos Graxos Dessaturases , Hemípteros , Animais , Ácidos Graxos Dessaturases/genética , Hemípteros/genética , Drosophila melanogaster , Ácidos Graxos Insaturados , Estearoil-CoA Dessaturase , Reprodução
3.
Mol Plant ; 16(12): 1951-1961, 2023 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-37897038

RESUMO

The diterpenoid paclitaxel (Taxol) is a chemotherapy medication widely used as a first-line treatment against several types of solid cancers. The supply of paclitaxel from natural sources is limited. However, missing knowledge about the genes involved in several specific metabolic steps of paclitaxel biosynthesis has rendered it difficult to engineer the full pathway. In this study, we used a combination of transcriptomics, cell biology, metabolomics, and pathway reconstitution to identify the complete gene set required for the heterologous production of paclitaxel. We identified the missing steps from the current model of paclitaxel biosynthesis and confirmed the activity of most of the missing enzymes via heterologous expression in Nicotiana benthamiana. Notably, we identified a new C4ß-C20 epoxidase that could overcome the first bottleneck of metabolic engineering. We used both previously characterized and newly identified oxomutases/epoxidases, taxane 1ß-hydroxylase, taxane 9α-hydroxylase, taxane 9α-dioxygenase, and phenylalanine-CoA ligase, to successfully biosynthesize the key intermediate baccatin III and to convert baccatin III into paclitaxel in N. benthamiana. In combination, these approaches establish a metabolic route to taxoid biosynthesis and provide insights into the unique chemistry that plants use to generate complex bioactive metabolites.


Assuntos
Biologia Sintética , Taxoides , Paclitaxel , Oxigenases de Função Mista
4.
PLoS Genet ; 19(9): e1010911, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37708138

RESUMO

Understanding the mechanism of detoxification initiation in arthropods after pesticide exposure is crucial. Although the identity of transcription factors that induce and regulate the expression of detoxification genes in response to pesticides is beginning to emerge, whether transcription factors directly interact with xenobiotics is unclear. The findings of this study revealed that a nuclear hormone receptor, Tetranychus cinnabarinus hormone receptor (HR) TcHR96h, regulates the overexpression of the detoxification gene TcGSTm02, which is involved in cyflumetofen resistance. The nuclear translocation of TcHR96h increased after cyflumetofen exposure, suggesting direct binding with cyflumetofen. The direct binding of TcHR96h and cyflumetofen was supported by several independent proteomic assays that quantify interactions with small molecules. Together, this study proposes a model for the initiation of xenobiotic detoxification in a polyphagous agricultural pest. These insights not only provide a better understanding of the mechanisms of xenobiotic detoxification and metabolism in arthropods, but also are crucial in understanding adaptation in polyphagous herbivores.


Assuntos
Artrópodes , Tetranychidae , Animais , Proteômica , Xenobióticos , Receptores Citoplasmáticos e Nucleares/genética , Fatores de Transcrição , Tetranychidae/genética
5.
Plant Physiol ; 193(2): 1227-1243, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37429000

RESUMO

The molecular innovation underpinning efficient carbon and energy metabolism during evolution of land plants remains largely unknown. Invertase-mediated sucrose cleavage into hexoses is central to fuel growth. Why some cytoplasmic invertases (CINs) function in the cytosol, whereas others operate in chloroplasts and mitochondria, is puzzling. We attempted to shed light on this question from an evolutionary perspective. Our analyses indicated that plant CINs originated from a putatively orthologous ancestral gene in cyanobacteria and formed the plastidic CIN (α1 clade) through endosymbiotic gene transfer, while its duplication in algae with a loss of its signal peptide produced the ß clade CINs in the cytosol. The mitochondrial CINs (α2) were derived from duplication of the plastidic CINs and coevolved with vascular plants. Importantly, the copy number of mitochondrial and plastidic CINs increased upon the emergence of seed plants, corresponding with the rise of respiratory, photosynthetic, and growth rates. The cytosolic CIN (ß subfamily) kept expanding from algae to gymnosperm, indicating its role in supporting the increase in carbon use efficiency during evolution. Affinity purification mass spectrometry identified a cohort of proteins interacting with α1 and 2 CINs, which points to their roles in plastid and mitochondrial glycolysis, oxidative stress tolerance, and the maintenance of subcellular sugar homeostasis. Collectively, the findings indicate evolutionary roles of α1 and α2 CINs in chloroplasts and mitochondria for achieving high photosynthetic and respiratory rates, respectively, which, together with the expanding of cytosolic CINs, likely underpin the colonization of land plants through fueling rapid growth and biomass production.


Assuntos
Embriófitas , beta-Frutofuranosidase , Humanos , Citosol/metabolismo , beta-Frutofuranosidase/metabolismo , Plantas/genética , Plantas/metabolismo , Embriófitas/metabolismo , Carbono/metabolismo , Evolução Molecular
6.
Plant J ; 116(4): 1172-1193, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37522418

RESUMO

Diurnal dark to light transition causes profound physiological changes in plant metabolism. These changes require distinct modes of regulation as a unique feature of photosynthetic lifestyle. The activities of several key metabolic enzymes are regulated by light-dependent post-translational modifications (PTM) and have been studied at depth at the level of individual proteins. In contrast, a global picture of the light-dependent PTMome dynamics is lacking, leaving the response of a large proportion of cellular function undefined. Here, we investigated the light-dependent metabolome and proteome changes in Arabidopsis rosettes in a time resolved manner to dissect their kinetic interplay, focusing on phosphorylation, lysine acetylation, and cysteine-based redox switches. Of over 24 000 PTM sites that were detected, more than 1700 were changed during the transition from dark to light. While the first changes, as measured 5 min after onset of illumination, occurred mainly in the chloroplasts, PTM changes at proteins in other compartments coincided with the full activation of the Calvin-Benson cycle and the synthesis of sugars at later timepoints. Our data reveal connections between metabolism and PTM-based regulation throughout the cell. The comprehensive multiome profiling analysis provides unique insight into the extent by which photosynthesis reprograms global cell function and adds a powerful resource for the dissection of diverse cellular processes in the context of photosynthetic function.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Fotossíntese , Processamento de Proteína Pós-Traducional , Proteínas de Arabidopsis/metabolismo , Cloroplastos/metabolismo
7.
J Exp Bot ; 74(6): 2146-2159, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36648335

RESUMO

The whitefly Bemisia tabaci is a piercing-sucking herbivore that reduces the yields of crops both by feeding on plants and transmitting plant viruses. Like most plant feeders, B. tabaci has evolved ways to avoid plant defence responses. For example, B. tabaci is known to secrete salivary effectors to suppress host defences. However, the nature of B. tabaci effectors is not completely understood. In this study, we used B. tabaci genomic and salivary gland transcriptomic data and an overexpression system to identify a previously unknown B. tabaci salivary effector, BtE3. BtE3 is specifically expressed in the head (containing primary salivary glands) and is secreted into hosts during B. tabaci feeding. In planta overexpression of BtE3 blocked Burkholderia glumae-induced hypersensitive response (HR) in both Nicotiana benthamiana and Solanum lycopersicum. Silencing of BtE3 by plant-mediated RNAi prevented B. tabaci from continuously ingesting phloem sap, and reduced B. tabaci survival and fecundity. Moreover, overexpression of BtE3 in planta up-regulated the salicylic acid- (SA-) signalling pathway, but suppressed the downstream jasmonic acid- (JA-) mediated defences. Taken together, these results indicate that BtE3 is a B. tabaci-specific novel effector involved in B. tabaci-plant interactions. These findings increase our understanding of B. tabaci effectors and suggest novel strategies for B. tabaci pest management.


Assuntos
Hemípteros , Solanum lycopersicum , Animais , Hemípteros/fisiologia , Nicotiana/genética , Transdução de Sinais , Solanum lycopersicum/genética , Produtos Agrícolas
8.
Science ; 375(6577): 146-147, 2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-35025656

RESUMO

Iron crystallization in super-Earth interiors plays a key role in their habitability.


Assuntos
Planeta Terra , Ferro
9.
Insect Sci ; 29(3): 827-839, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34309214

RESUMO

The two-spotted spider mite Tetranychus urticate is an important agricultural pest worldwide. It is extremely polyphagous and has developed resistance to many pesticides. Here, we assessed the pesticide resistance of seven field populations of T. urticae in China, their target site mutations and the activities of their detoxification enzymes. The results showed that abamectin and the traditional pesticides pyridaben, profenofos and bifenthrin had higher resistance or lower toxicity than more recently developed pesticides including chlorfenapyr, spinetoram, cyflumetofen, cyenopyrafen, bifenazate and B-azolemiteacrylic. The frequency of point mutations related to abamectin resistance, G314D in the glutamate-gated chloride channel 1 (GluCl1) and G326E in GluCl3, ranged 47%-70% and 0%-97%, respectively. The frequency of point mutations in A1215D and F1538I of the voltage-gated sodium channel gene (VGSC), which may increase resistance to pyrethroids, ranged 88%-100% and 10%-100%, respectively. For target sites related to organophosphate resistance, mutation frequencies ranged 25%-92% for G119S and 0%-23% for A201S in the acetycholinesterase gene (Ace). Mutation G126S in the bifenazate resistance-related cytochrome b gene (Cytb) was observed in three of the seven T. urticae populations. Higher activities of detoxification enzymes (P450, GST, CarEs and UGTs) were observed in two T. urticae populations, with significant difference in the XY-SX population. These results provide useful information on the status of pesticide resistance of T. urticae in China and suggest that T. urticae field populations may have multiple resistance mechanisms.


Assuntos
Acaricidas , Praguicidas , Tetranychidae , Canais de Sódio Disparados por Voltagem , Acaricidas/farmacologia , Agricultura , Animais , Mutação , Tetranychidae/genética , Canais de Sódio Disparados por Voltagem/genética
10.
Pest Manag Sci ; 78(3): 1128-1137, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34796637

RESUMO

BACKGROUND: Whitefly (Bemisia tabaci) is a typical pest that causes severe damage to hundreds of agricultural crops. The trehalose-6-phosphate synthase (TPS) genes, as the key genes in the insect trehalose synthesis pathway, are important for insect growth and development. The whitefly TPS genes may be a main reason for the severe damage and may represent potential targets for the control of whiteflies. RESULTS: In this study, we identified and cloned three TPS genes from B. tabaci MED and found that the BtTPS1 and BtTPS2 genes showed higher expression levels than the BtTPS3 gene. Then, RNA interference (RNAi) of BtTPS1 and BtTPS2 resulted in significant mortality and influenced the expression of related genes involved in energy metabolism and chitin biosynthesis in whitefly adults. Finally, the transgenic tobacco plants showed a significant effect on B. tabaci, and knockdown of BtTPS1 or BtTPS2 led to retarded growth and low hatchability in whitefly nymphs, and caused 90% mortality and decreased the fecundity in whitefly adults. Additionally, the transgenic tobacco with combinatorial RNAi of BtTPS1 and BtTPS2 showed a better efficacy against whiteflies than individual silencing. CONCLUSION: Our results suggest that silencing of the BtTPS genes can compromise the growth and development of whiteflies, offering not only a new option for whitefly control but also a secure and environmentally friendly management strategy.


Assuntos
Hemípteros , Animais , Produtos Agrícolas , Hemípteros/genética , Plantas Geneticamente Modificadas/genética , Interferência de RNA , Nicotiana/genética
11.
Plant Commun ; 2(5): 100235, 2021 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-34746764

RESUMO

Synthetic biology has been developing rapidly in the last decade and is attracting increasing attention from many plant biologists. The production of high-value plant-specific secondary metabolites is, however, limited mostly to microbes. This is potentially problematic because of incorrect post-translational modification of proteins and differences in protein micro-compartmentalization, substrate availability, chaperone availability, product toxicity, and cytochrome p450 reductase enzymes. Unlike other heterologous systems, plant cells may be a promising alternative for the production of high-value metabolites. Several commercial plant suspension cell cultures from different plant species have been used successfully to produce valuable metabolites in a safe, low cost, and environmentally friendly manner. However, few metabolites are currently being biosynthesized using plant platforms, with the exception of the natural pigment anthocyanin. Both Arabidopsis thaliana and Nicotiana tabacum cell cultures can be developed by multiple gene transformations and CRISPR-Cas9 genome editing. Given that the introduction of heterologous biosynthetic pathways into Arabidopsis and N. tabacum is not widely used, the biosynthesis of foreign metabolites is currently limited; however, therein lies great potential. Here, we discuss the exemplary use of plant cell cultures and prospects for using A. thaliana and N. tabacum cell cultures to produce valuable plant-specific metabolites.


Assuntos
Arabidopsis , Técnicas de Cultura de Células , Engenharia Metabólica/métodos , Nicotiana , Células Vegetais/metabolismo , Biologia Sintética/métodos
12.
EMBO J ; 40(15): e106800, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34156108

RESUMO

How organisms integrate metabolism with the external environment is a central question in biology. Here, we describe a novel regulatory small molecule, a proteogenic dipeptide Tyr-Asp, which improves plant tolerance to oxidative stress by directly interfering with glucose metabolism. Specifically, Tyr-Asp inhibits the activity of a key glycolytic enzyme, glyceraldehyde 3-phosphate dehydrogenase (GAPC), and redirects glucose toward pentose phosphate pathway (PPP) and NADPH production. In line with the metabolic data, Tyr-Asp supplementation improved the growth performance of both Arabidopsis and tobacco seedlings subjected to oxidative stress conditions. Moreover, inhibition of Arabidopsis phosphoenolpyruvate carboxykinase (PEPCK) activity by a group of branched-chain amino acid-containing dipeptides, but not by Tyr-Asp, points to a multisite regulation of glycolytic/gluconeogenic pathway by dipeptides. In summary, our results open the intriguing possibility that proteogenic dipeptides act as evolutionarily conserved small-molecule regulators at the nexus of stress, protein degradation, and metabolism.


Assuntos
Arabidopsis/efeitos dos fármacos , Dipeptídeos/farmacologia , Gliceraldeído-3-Fosfato Desidrogenases/antagonistas & inibidores , Nicotiana/efeitos dos fármacos , Proteínas de Plantas/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/metabolismo , Simulação por Computador , Dipeptídeos/química , Dipeptídeos/metabolismo , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/química , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/metabolismo , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , NADP/metabolismo , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Via de Pentose Fosfato/efeitos dos fármacos , Fosfoenolpiruvato Carboxiquinase (ATP)/metabolismo , Proteínas de Plantas/antagonistas & inibidores , Plântula/efeitos dos fármacos , Plântula/metabolismo , Nicotiana/metabolismo
13.
Appl Environ Microbiol ; 87(13): e0046621, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-33893113

RESUMO

Deciphering the molecular mechanisms underlying insect resistance to Cry toxins produced by Bacillus thuringiensis (Bt) is pivotal for the sustainable utilization of Bt biopesticides and transgenic Bt crops. Previously, we identified that mitogen-activated protein kinase (MAPK)-mediated reduced expression of the PxABCB1 gene is associated with Bt Cry1Ac resistance in the diamondback moth, Plutella xylostella (L.). However, the underlying transcriptional regulation mechanism remains enigmatic. Here, the PxABCB1 promoter in Cry1Ac-susceptible and Cry1Ac-resistant P. xylostella strains was cloned and analyzed and found to contain a putative Jun binding site (JBS). A dual-luciferase reporter assay and yeast one-hybrid assay demonstrated that the transcription factor PxJun repressed PxABCB1 expression by interacting with this JBS. The expression levels of PxJun were increased in the midguts of all resistant strains compared to the susceptible strain. Silencing of PxJun expression significantly elevated PxABCB1 expression and Cry1Ac susceptibility in the resistant NIL-R strain, and silencing of PxMAP4K4 expression decreased PxJun expression and also increased PxABCB1 expression. These results indicate that MAPK-activated PxJun suppresses PxABCB1 expression to confer Cry1Ac resistance in P. xylostella, deepening our understanding of the transcriptional regulation of midgut Cry receptor genes and the molecular basis of insect resistance to Bt Cry toxins. IMPORTANCE The transcriptional regulation mechanisms underlying reduced expression of Bt toxin receptor genes in Bt-resistant insects remain elusive. This study unveils that a transcription factor PxJun activated by the MAPK signaling pathway represses PxABCB1 expression and confers Cry1Ac resistance in P. xylostella. Our results provide new insights into the transcriptional regulation mechanisms of midgut Cry receptor genes and deepen our understanding of the molecular basis of insect resistance to Bt Cry toxins. To our knowledge, this study identified the first transcription factor that can be involved in the transcriptional regulation mechanisms of midgut Cry receptor genes in Bt-resistant insects.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Toxinas de Bacillus thuringiensis/farmacologia , Endotoxinas/farmacologia , Proteínas Hemolisinas/farmacologia , Proteínas de Insetos/genética , Resistência a Inseticidas/genética , Proteínas Quinases Ativadas por Mitógeno/genética , Mariposas , Proteínas Proto-Oncogênicas c-jun/genética , Animais , Larva/genética , Larva/metabolismo , Mariposas/genética , Mariposas/metabolismo
14.
Cell ; 184(7): 1693-1705.e17, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33770502

RESUMO

Plants protect themselves with a vast array of toxic secondary metabolites, yet most plants serve as food for insects. The evolutionary processes that allow herbivorous insects to resist plant defenses remain largely unknown. The whitefly Bemisia tabaci is a cosmopolitan, highly polyphagous agricultural pest that vectors several serious plant pathogenic viruses and is an excellent model to probe the molecular mechanisms involved in overcoming plant defenses. Here, we show that, through an exceptional horizontal gene transfer event, the whitefly has acquired the plant-derived phenolic glucoside malonyltransferase gene BtPMaT1. This gene enables whiteflies to neutralize phenolic glucosides. This was confirmed by genetically transforming tomato plants to produce small interfering RNAs that silence BtPMaT1, thus impairing the whiteflies' detoxification ability. These findings reveal an evolutionary scenario whereby herbivores harness the genetic toolkit of their host plants to develop resistance to plant defenses and how this can be exploited for crop protection.


Assuntos
Hemípteros/genética , Proteínas de Insetos/metabolismo , Solanum lycopersicum/genética , Toxinas Biológicas/metabolismo , Animais , Transferência Genética Horizontal , Genes de Plantas , Glucosídeos/química , Glucosídeos/metabolismo , Hemípteros/fisiologia , Herbivoria , Proteínas de Insetos/antagonistas & inibidores , Proteínas de Insetos/classificação , Proteínas de Insetos/genética , Mucosa Intestinal/metabolismo , Solanum lycopersicum/metabolismo , Malonil Coenzima A/metabolismo , Filogenia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Interferência de RNA , RNA de Cadeia Dupla/metabolismo , Toxinas Biológicas/química
15.
Pestic Biochem Physiol ; 171: 104744, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33357566

RESUMO

The sweetpotato whitefly Bemisia tabaci is a polyphagous crop pest distributed worldwide and frequent exposure to many different defensive secondary metabolites in its host plants. To counteract these defensive plant secondary metabolites, B. tabaci elevate their production of detoxification enzymes, including cytochrome P450 monooxygenases. Besides their tolerance to phytotoxin, B. tabaci have quickly developed resistance to various insecticides in the field. However, the relationship between host plant secondary metabolites and insecticide resistance in B. tabaci is not fully understood. In this study, the influence of plant flavonoid ingestion on B. tabaci tolerance to thiamethoxam and flupyradifurone insecticides and its possible mechanism were examined. Eight plant flavonoids were screened to evaluate their effects on B. tabaci adult sensitivity to thiamethoxam and flupyradifurone. Of which rutin, quercetin, kaempferol, myricetin and catechin significantly reduced adult sensitivity to thiamethoxam and flupyradifurone. Application of cytochrome P450 inhibitor piperonyl butoxide significantly increased the mortality of B. tabaci adults treated with thiamethoxam and flupyradifurone. Moreover, flavonoid ingestion predominantly enhanced the activity of cytochrome P450 enzyme in B. tabaci adults. Meanwhile, the expression level of three cytochrome P450 genes, CYP6CM1, CYP6CX4 and CYP4C64 were induced by the flavonoids in B. tabaci adults. In conclusion, plant flavonoids enhanced the tolerance to thiamethoxam and flupyradifurone in B. tabaci and cytochrome P450s may contribute the flavonoid adaptation. The reduced sensitivity of thiamethoxam and flupyradifurone in flavonoid-fed B. tabaci adults suggested that previous exposure to the host plant-derived flavonoids is likely to compromise the efficacy of insecticides.


Assuntos
Hemípteros , Inseticidas , 4-Butirolactona/análogos & derivados , Animais , Flavonoides/farmacologia , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Piridinas , Tiametoxam
16.
Pest Manag Sci ; 77(3): 1204-1213, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33034948

RESUMO

BACKGROUND: The two-spotted spider mite Tetranychus urticae is a polyphagous and cosmopolitan pest that has developed high resistance to abamectin, making it difficult to control. Although 'target resistance' related to glutamate-gated chloride channel mutations was found in T. urticae field populations in China, other resistance mechanisms appear to be involved. Here, we conducted genome-wide transcriptome profiling using RNA-sequencing of two abamectin-resistant populations (NB-ZJ and SY-BJ) and one susceptible strain (Lab-SS) to identify differentially expressed genes that might contribute to the resistance of T. urticae to abamectin in China. RESULTS: Our experiments showed that abamectin resistance was synergized by piperonyl butoxide (PBO) and triphenyl phosphate (TPP), with synergistic ratios (SR) of 2.95-fold and 2.21-fold for PBO and 3.55-fold and 2.84-fold for TPP in NB-ZJ and SY-BJ populations, respectively. Transcriptome data and quantitative real-time PCR (qRT-PCR) revealed that seven detoxification enzyme genes were overexpressed in the two resistant populations. Furthermore, functional analysis by RNA interference (RNAi) indicated that the mortality caused by abamectin was significantly increased by the separate silencing of the P450 genes CYP389C10, CYP392D8, CYP392A11, and CYP392A12. CONCLUSION: qRT-PCR expression and RNAi data suggest that the overexpression of P450 genes CYP389C10, CYP392D8, CYP392A11, and CYP392A12 may be involved in the abamectin-resistance of field populations of T. urticae in China. This knowledge could facilitate the elucidation of resistance mechanisms and the development of resistance management of T. urticae field populations. © 2020 Society of Chemical Industry.


Assuntos
Tetranychidae , Animais , China , Sistema Enzimático do Citocromo P-450/genética , Perfilação da Expressão Gênica , Ivermectina/análogos & derivados , Tetranychidae/genética
17.
Plant Commun ; 1(5): 100028, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-33367253

RESUMO

Although the use of stable transformation technology has led to great insight into gene function, its application in high-throughput studies remains arduous. Agro-infiltration have been widely used in species such as Nicotiana benthamiana for the rapid detection of gene expression and protein interaction analysis, but this technique does not work efficiently in other plant species, including Arabidopsis thaliana. As an efficient high-throughput transient expression system is currently lacking in the model plant species A. thaliana, we developed a method that is characterized by high efficiency, reproducibility, and suitability for transient expression of a variety of functional proteins in A. thaliana and 7 other plant species, including Brassica oleracea, Capsella rubella, Thellungiella salsuginea, Thellungiella halophila, Solanum tuberosum, Capsicum annuum, and N. benthamiana. Efficiency of this method was independently verified in three independent research facilities, pointing to the robustness of this technique. Furthermore, in addition to demonstrating the utility of this technique in a range of species, we also present a case study employing this method to assess protein-protein interactions in the sucrose biosynthesis pathway in Arabidopsis.


Assuntos
Agrobacterium/genética , Edição de Genes/métodos , Expressão Gênica/genética , Plantas/genética , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas/genética , Transferência Genética Horizontal , Folhas de Planta/genética , Folhas de Planta/metabolismo , Purificação por Afinidade em Tandem , Transformação Genética
18.
Curr Protoc Plant Biol ; 5(3): e20115, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32841544

RESUMO

As the principal co-factors of many metabolic pathways, the measurement of both adenine nucleotides and nicotinamide adenine dinucleotide provides important information about cellular energy metabolism. However, given their rapid and reversible conversion as well as their relatively low concentration ranges, it is difficult to measure these compounds. Here, we describe a highly sensitive and selective ion-pairing HPLC method with fluorescence detection to quantify adenine nucleotides in plants. In addition, nicotinamide adenine dinucleotide is a crucially important redox-active substrate for multiple catabolic and anabolic reactions with the ratios of NAD+ /NADH and NADP+ /NADPH being suggested as indicators of the general intracellular redox potential and hence metabolic state. Here, we describe highly sensitive enzyme cycling-based colorimetric assays (with a detection limit in the pmol range) performed subsequent to a simple extraction procedure involving acid or base extraction to allow the measurement of the cellular levels of these metabolites. © 2020 The Authors. Basic Protocol 1: Preparation of plant material for the measurement Basic Protocol 2: Measurement of ATP, ADP, and AMP via HPLC Basic Protocol 3: NAD+ /NADP+ measurements Basic Protocol 4: NADH/NADPH measurements Basic Protocol 5: Data analysis and quality control approaches.


Assuntos
Nucleotídeos de Adenina , NAD , Cromatografia Líquida de Alta Pressão , NADP , Oxirredução
19.
Phys Rev Lett ; 125(7): 078501, 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32857557

RESUMO

We measure the electrical resistivity of hcp iron up to ∼170 GPa and ∼3000 K using a four-probe van der Pauw method coupled with homogeneous flattop laser heating in a DAC, and compute its electrical and thermal conductivity by first-principles molecular dynamics including electron-phonon and electron-electron scattering. We find that the measured resistivity of hcp iron increases almost linearly with temperature, and is consistent with our computations. The results constrain the resistivity and thermal conductivity of hcp iron to ∼80±5 µΩ cm and ∼100±10 W m^{-1} K^{-1}, respectively, at conditions near the core-mantle boundary. Our results indicate an adiabatic heat flow of ∼10±1 TW out of the core, supporting a present-day geodynamo driven by thermal and compositional convection.

20.
Front Physiol ; 11: 709, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32695020

RESUMO

The olfactory system serves a vital role in the evolution and survival of insects, being involved in behaviors such as host seeking, foraging, mating, and oviposition. Odorant-binding proteins (OBPs) and chemosensory proteins (CSPs) are involved in the olfactory recognition process. In this study, BtabCSP11, a CSP11 gene from the whitefly Bemisia tabaci, was cloned and characterized. The open reading frame of BtabCSP11 encodes 136 amino acids, with four highly conserved cysteine residues. The temporal and spatial expression profiles showed that BtabCSP11 was highly expressed in the abdomens of B. tabaci females. Dietary RNA interference (RNAi)-based functional analysis showed substantially reduced fecundity in parthenogenetically reproduced females, suggesting a potential role of BtabCSP11 in B. tabaci reproduction. These combined results expand the function of CSPs beyond chemosensation.

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