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1.
Insects ; 12(11)2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34821796

RESUMO

Cotton is a major crop of Pakistan, and Bemisia tabaci (Homoptera: Aleyrodidae) is a major pest of cotton. Due to the unwise and indiscriminate use of insecticides, resistance develops more readily in the whitefly. The present study was conducted to evaluate the resistance development in the whitefly against the different insecticides that are still in use. For this purpose, the whitefly population was selected with five concentrations of each insecticide, for five generations. At G1, compared with the laboratory susceptible population, a very low level of resistance was observed against bifenthrin, cypermethrin, acetamiprid, imidacloprid, thiamethoxam, nitenpyram, chlorfenapyr, and buprofezin with a resistance ratio of 3-fold, 2-fold, 1-fold, 4-fold, 3-fold, 3-fold, 3-fold, and 3-fold, respectively. However, the selection for five generations increased the resistance to a very high level against buprofezin (127-fold), and to a high level against imidacloprid (86-fold) compared with the laboratory susceptible population. While, a moderate level of resistance was observed against cypermethrin (34-fold), thiamethoxam (34-fold), nitenpyram (30-fold), chlorfenapyr (29-fold), and acetamiprid (21-fold). On the other hand, the resistance was low against bifenthrin (18-fold) after selection for five generations. A very low level of resistance against the field population of B. tabaci, at G1, showed that these insecticides are still effective, and thus can be used under the field conditions for the management of B. tabaci. However, the proper rotation of insecticides among different groups can help to reduce the development of resistance against insecticides.

2.
Biology (Basel) ; 10(7)2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34356469

RESUMO

The proper synthesis and functioning of ecdysteroids and juvenile hormones (JHs) are very important for the regulation of vitellogenesis and oogenesis. However, their role and function contrast among different orders, and even in the same insect order. For example, the JH is the main hormone that regulates vitellogenesis in hemimetabolous insect orders, which include Orthoptera, Blattodea, and Hemiptera, while ecdysteroids regulate the vitellogenesis among the insect orders of Diptera, some Hymenoptera and Lepidoptera. These endocrine hormones also regulate each other. Even at some specific stage of insect life, they positively regulate each other, while at other stages of insect life, they negatively control each other. Such positive and negative interaction of 20-hydroxyecdysone (20E) and JH is also discussed in this review article to better understand the role of these hormones in regulating the reproduction. Therefore, the purpose of the present review is to deeply understand the complex interaction of endocrine hormones with each other and with the insulin signaling pathway. The role of microbiomes in the regulation of the insect endocrine system is also reviewed, as the endocrine hormones are significantly affected by the compounds produced by the microbiota.

3.
Pestic Biochem Physiol ; 173: 104801, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33771250

RESUMO

Rotenone, a selective inhibitor of mitochondrial complex I, has been extensively studied on kinds of neuron and neuroblast in Parkinson's disease. However, little is known about the potential mechanism of this promising botanical insecticide upon insect cells. In the article, cell proliferation of two Lepidoptera cell lines, Spodoptera litura SL-1 cells and Spodoptera frugiperda Sf9 cells, were all inhibited by rotenone in a time- and dose-dependent manner. Typical necrotic characteristics of cell morphology and ultrastructure, such as plasma membrane collapses and organelle lyses, were all observed by transmission electron microscope and scanning electron microscope. Moreover, irregular DNA degradation was also detected by DNA gel electrophoresis and Hoechst 33258 staining, while the typical apoptotic feature, DNA ladder, hadn't been observed. Flow cytometric analysis showed that rotenone-induced cell death of Sf9 and SL-1 cells accompanied with the plasma membrane potential depolarization and mitochondrial membrane potential reduction. Furthermore, the activity of Na+-K+-ATPase was detected in our study. In conclusion, rotenone could cause necrosis but not apoptosis in insect cells through a mitochondrial- and plasmic membrane-dependent pattern, which shed a light on the rotenone-induced cytotoxicity on insects.


Assuntos
Apoptose , Rotenona , Animais , Membrana Celular , Potencial da Membrana Mitocondrial , Mitocôndrias/metabolismo , Necrose/induzido quimicamente , Rotenona/toxicidade
4.
J Agric Food Chem ; 69(1): 126-134, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33393782

RESUMO

Short-range semiochemicals convey individual-specific information, which is important for final successful courtship and copulation. In this study, an electroantennography (EAG) instrument was used to determine the legs of male Bactrocera dorsalis that might participate in the perception of 4-allyl-2,6-dimethoxyphenol (4-DMP), a female-biased cuticular hydrocarbon (CHC) component. By performing comparative RNA-seq analysis, nine differentially expressed OBPs between 4-DMP-stimulated (M4-DMP) and unstimulated (M) male flies were screened out. Among the four downregulated OBPs, BdorOBP2 exhibited the strongest binding to 4-DMP than BdorOBP4, BdorOBP19a, and BdorOBP56h. Functional analyses confirmed that the reduction in transcript abundance of BdorOBP2 led to a significant decrease in behavioral responses of male flies to 4-DMP. In silico simulation revealed dramatic changes in the key residues and conformation between the two complexes, implying that BdorOBP2 might activate different receptors after binding to 4-DMP or methyl eugenol (ME). The results of this study suggest that BdorOBP2 mediates behavioral responses to 4-DMP and could be a promising molecular target for strategies of pest control.


Assuntos
Eugenol/análogos & derivados , Proteínas de Insetos/metabolismo , Receptores Odorantes/metabolismo , Atrativos Sexuais/metabolismo , Tephritidae/metabolismo , Animais , Eugenol/química , Eugenol/metabolismo , Feminino , Proteínas de Insetos/química , Proteínas de Insetos/genética , Masculino , Receptores Odorantes/química , Receptores Odorantes/genética , Atrativos Sexuais/química , Tephritidae/química , Tephritidae/genética
5.
Phys Chem Chem Phys ; 22(41): 23847-23855, 2020 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-33073276

RESUMO

To find potential alkaline-earth metal-doped aromatic superconductors and clarify the origin of superconductivity in metal-doped phenanthrene (PHN) systems, we have systematically investigated the crystal and electronic structures of bivalent metal (Mg, Ca, Sr and Ba)-doped PHNs by first-principles calculations. The results show that only Ba1.5PHN can satisfy the conditions of both thermodynamic stability and metallization. We predicted that Ba1.5PHN is superconducting with the critical temperature of 5.3 K. Based on the metal atomic radius and electronegativity and combined with monovalent metal- and trivalent metal-doped PHNs, the relations among charge transfer, metallization, and superconductivity were analyzed. The results indicate that the electronegativity of the metal element rather than the atomic radius is predominant in the charge transfer and superconductivity of metal-doped phenanthrene.

6.
Nanotechnology ; 31(48): 485202, 2020 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-32931468

RESUMO

Full static x-ray computed tomography (CT) technology has enabled higher precision and resolution imaging and has been applied in many applications such as diagnostic medical imaging, industrial inspection and security screening. In this technique, the x-ray source section is mainly composed of a thermionic cathode and electron beam scanning system. However, they have several shortcomings such as limited scanning angle, long response time and large volume. Distributed and programmable cold cathode (i.e. carbon nanotubes, ZnO nanowires (NWs)) field-emission x-ray sources are expected to solve these problems. However, there have been several long-standing challenges to the application of such cold field emitters for x-ray sources, such as the short lifetime and rigorous fabrication process, which have fundamentally prevented their widespread use. Here, we propose and demonstrate a cold field-emission x-ray source based on a graphene oxide (GO)-coated cuprous sulfide nanowire (Cu2S NW/GO) cathode. The proposed Cu2S NW/GO x-ray source provides stable emission (>18 h at a direct voltage of 2600 V) and has a low threshold (4.5 MV m-1 for obtaining a current density of 1 µA cm-2), benefiting from the demonstrated key features such as in situ epitaxy growth of Cu2S NWs on Cu, nanometer-scale sharp protrusions within GO and charge transfer between the Cu2S NWs and GO layer. Our research provides a simple and robust method to obtain a high-performance cold field emitter, leading to great potential for the next generation of x-ray source and CT.

7.
Artigo em Inglês | MEDLINE | ID: mdl-32850741

RESUMO

The well-studied quorum sensing (QS) mechanism has established a complex knowledge system of how microorganisms behave collectively in natural ecosystems, which contributes to bridging the gap between the ecological functions of microbial communities and the molecular mechanisms of cell-to-cell communication. In particular, the ability of agrochemical degradation has been one most attractive potential of functional bacteria, but the interaction and mutual effects of intracellular degradation and intraspecific behavior remained unclear. In this study, we establish a connection between QS regulation and biodegradation by harnessing the previously isolated Bacillus subtilis BSF01 as a template which degrades various pyrethroids. First, we characterize the genetic and transcriptional basis of comA-involved QS system in B. subtilis BSF01 since the ComQXPA circuit coordinates group behaviors in B. subtilis isolates. Second, the genetic and transcriptional details of pyrethroid-degrading carboxylesterase CesB are defined, and its catalytic capacity is evaluated under different conditions. More importantly, we adopt DNA pull-down and yeast one-hybrid techniques to reveal that the enzymatic degradation of pyrethroids is initiated through QS signal regulator ComA binding to carboxylesterase gene cesB, highlighting the synergistic effect of QS regulation and pyrethroid degradation in B. subtilis BSF01. Taken together, the elucidated mechanism provides novel details on the intercellular response of functional bacteria against xenobiotic exposure, which opens up possibilities to facilitate the in-situ contaminant bioremediation via combining the QS-mediated strategies.

8.
J Hazard Mater ; 398: 122954, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-32506048

RESUMO

The ubiquitous contamination generating from the frequent input of agrochemicals is a major hurdle affecting the ecological sustainability of agroecosystems. Here, we investigated the dissipation of multiple pesticides in the subtropical rice-dominated landscapes under tillage intensity management, and unveiled the vital role of soil microbiome in promoting xenobiotic degradation. Three commonly used pesticides (including herbicide butachlor, insecticide clothianidin and fungicide tricyclazole) showed rapid dissipation dynamics in the field where the reduction of tillage intensity with straw incorporation was conducted. In response to pesticide exposure, soil microbial communities adapted quickly with slight changes in community composition and diversity. Meanwhile, the microbial xenobiotic degradation-related functions were stimulated, which possibly related to the increased organic carbon and nitrogen in soil. Importantly, these shifts and effects on microbial communities and functions gradually declined after a length of rice growing seasons, suggesting the flexibility of soil microbiome in tackling with long-term xenobiotic disturbance to maintain a diverse and vibrant soil biota. Overall, our study that displayed the enhanced agrochemical dissipation which benefited markedly from the interaction of tillage management and soil microbial functioning, provides important basis and insights for facilitating green, balanced and sustainable agriculture.


Assuntos
Microbiota , Oryza , Agricultura , Agroquímicos , Solo , Microbiologia do Solo , Xenobióticos
9.
Int J Mol Sci ; 21(8)2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32326478

RESUMO

As an important type of programmed cell death, apoptosis plays a critical role in lepidopteran insects in response to various internal and external stresses. It is controlled by a network of genes such as those encoding the inhibitor of apoptosis proteins. However, there are few studies on apoptosis-related genes in Spodoptera frugiperda. In this study, an orthologue to the Drosophila reaper gene, named Sf-IBM1, was identified from S. frugiperda, and a full-length sequence was obtained by reverse transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends PCR (RACE-PCR). The expression pattern of Sf-IBM1 was determined in different developmental stages and various tissues. Apoptotic stimuli including azadirachtin, camptothecin, and ultraviolet radiation (UV) induced the expression of Sf-IBM1 at both transcript and protein levels. Overexpression of Sf-IBM1 induced apoptosis in Sf9 cells, and the Sf-IBM1 protein was localized in mitochondria. The apoptosis induced by Sf-IBM1 could be blocked by the caspase universal inhibitor carbobenzoxy-valyl-alanyl-aspartyl-[O-methyl]-fluoromethylketone (Z-VAD-FMK) and Sf-IAP1. Our results provide valuable information that should contribute to a better understanding of the molecular events that lead to apoptosis in lepidopterans.


Assuntos
Apoptose/genética , Inibidores de Caspase/farmacologia , Proteínas de Insetos/metabolismo , Histona Desmetilases com o Domínio Jumonji/metabolismo , Mitocôndrias/metabolismo , Spodoptera/metabolismo , Clorometilcetonas de Aminoácidos/farmacologia , Sequência de Aminoácidos , Animais , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Proteína 3 com Repetições IAP de Baculovírus/farmacologia , Camptotecina/farmacologia , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Insetos/genética , Histona Desmetilases com o Domínio Jumonji/genética , Limoninas/farmacologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/efeitos da radiação , Filogenia , Reação em Cadeia da Polimerase em Tempo Real , Células Sf9 , Spodoptera/genética , Spodoptera/crescimento & desenvolvimento , Spodoptera/efeitos da radiação , Raios Ultravioleta , Regulação para Cima
10.
Molecules ; 25(5)2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32155800

RESUMO

The increasing resistance of rice sheath blight caused by Rhizoctonia solani highlights the need for highly effective and environmentally benign agents. Natural ß-carboline alkaloids were simplified to obtain a series of indole derivatives, and their fungicidal activity and preliminary mode of action against R. solani were also evaluated. The initial hit indole (7) displayed significant fungicidal activity with an EC50 value of 25.56 µg/mL, and was selected for further optimization. Importantly, compound 55, the most active compound, had an EC50 value of 0.62 µg/mL, and approximately 300-fold more potent than validamycin A (EC50 = 183.00 µg/mL). In vivo bioassay also demonstrated that compound 55 showed better fungicidal activities than validamycin A. Moreover, the mechanism studies revealed that compound 55 not only caused remarkable morphological and structural alterations of R. solani hyphae, but also induced the loss of mitochondrial membrane potential and interfered with DNA synthesis. Therefore, compound 55 showed superior fungicidal activity against R. solani, and the elucidated mode of action supported the potential application of compound 55 against rice sheath blight.


Assuntos
Alcaloides/química , Alcaloides/farmacologia , Carbolinas/química , Carbolinas/farmacologia , Fungicidas Industriais/química , Indóis/química , Permeabilidade da Membrana Celular/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Estrutura Molecular , Fenótipo , Doenças das Plantas/microbiologia , Espécies Reativas de Oxigênio/metabolismo , Rhizoctonia/efeitos dos fármacos , Rhizoctonia/metabolismo , Rhizoctonia/ultraestrutura , Relação Estrutura-Atividade
11.
Ecotoxicol Environ Saf ; 190: 110134, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31901541

RESUMO

The widely distributed ß-carboline alkaloids exhibit promising psychopharmacological and biochemical effects. Harmine, a natural ß-carboline, can inhibit insect growth and development with unclear mechanisms. In this study, harmine (at 0-200 mg/L) showed a dose-dependent inhibitory effect on the pupal weight, length, height, pupation rate and eclosion rate of fruit flies Drosophila melanogaster, which was similar to the inhibition induced by the well-known botanical insect growth regulator azadirachtin. Moreover, the expression levels of major regulators from the developmental signaling network were down-regulated during the pupal stage except Numb, Fringe, Yorkie and Pten. The Notch, Wnt, Hedgehog and TGF-ß pathways mainly played vital roles in coping with harmine exposure in pupae stage, while the Hippo, Hedgehog and TGF-ß elements were involved in the sex differences. Notch, Hippo, Hedgehog, Dpp and Armadillo were proved to be suppressed in the developmental inhibition with fly mutants, while Numb and Punt were increased by harmine. In conclusion, harmine significantly inhibited the development of Drosophila by negatively affecting their developmental signaling network during different stages. Our results establish a preliminary understanding of the developmental signaling network subjected to botanical component-induced growth inhibition and lay the groundwork for further application.


Assuntos
Alcaloides/metabolismo , Drosophila melanogaster/fisiologia , Harmina/metabolismo , Animais , Carbolinas , Regulação para Baixo/efeitos dos fármacos , Proteínas de Drosophila/genética , Drosophila melanogaster/metabolismo , Drosophilidae , Hormônios Juvenis , Limoninas , Proteínas Nucleares , Pupa/metabolismo , Transativadores
12.
J Proteomics ; 211: 103573, 2020 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-31683062

RESUMO

The fall armyworm, Spodoptera frugiperda, is an important invasive pest and exhibits resistance to many insecticides. Harmine, a remarkable, natural ß-carboline alkaloid, exhibits a variety of bioactivities and induces programmed cell death in Sf9 cells. In the present study, transcriptomic and proteomic analyses were combined to investigate the effects of harmine on Sf9 cells. A sublethal dose, 0.05 mM, was selected and the transcriptomic analysis revealed 2463 upregulated and 689 downregulated genes after harmine treatment. The most frequently enriched pathways of differentially expressed genes (DEGs) were mainly involved in drug and xenobiotic metabolism. The proteomics analysis revealed 36 upregulated and 77 downregulated proteins, and the results showed a nonlinear relationship with mRNA expression. All the genes related to detoxification and resistance in the transcriptome and DEGs were identified and annotated. Complete open reading frames of 27 cytochrome P450s (CYPs), 27 glutathione S-transferases (GSTs), 11 carboxylesterases (CarEs), 10 UDP-glucuronosyltransferases (UGTs) and 29 heat shock proteins (HSPs) were assembled and verified using qRT-PCR. Harmine exhibited a completely different detoxification mechanism from normal pesticides. The Sigma and Delta class GSTs and UGTs might play important roles, rather than CYP6 and CYP9 clans, CarEs or HSPs. BIOLOGICAL SIGNIFICANCE: Harmine, a natural ß-carboline alkaloid, inhibits the cell proliferation and induces programmed cell death of Sf9 cells, which derived from Spodoptera frugiperda, an important world invasive pest. In the article, the combined transcriptomic and proteomic analysis is used to explore the potential solution for its resistance management. These results supporting that harmine can be applied as a novel adjuvant or pesticide. In addition, the systematically identified resistance-related genes in fall armyworm provide the foundation for potential resistance monitoring and management.


Assuntos
Inseticidas , Transcriptoma , Animais , Harmina , Inseticidas/farmacologia , Proteômica , Células Sf9 , Spodoptera/genética
13.
Phys Chem Chem Phys ; 22(3): 1069-1077, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31872838

RESUMO

As one of the simplest hydrocarbons, methane (CH4) has great potential in the research of superconductors. However, the metallization of CH4 has been an issue for a long time. Here, we report the structure, metallization, and superconductivity of CH4 doped by Be at low pressures, based on first-principles calculations. The result shows that the thermodynamically stable BeCH4 with P1[combining macron] space-group can transform into a metal at ambient pressure. This ternary hydride BeCH4 exhibits a superconductivity of ∼6 K below 25.6 GPa. Interestingly, the superconducting critical temperature of BeCH4 can reach ∼30 K at 80 GPa in the form of an a-P1 space-group phase. The charge transfer from Be to CH4 molecules plays an important role in the superconductivity. Our results present a novel way to realize the metallization of methane at relative pressures and indicate that the doped methane is a potential candidate for seeking high temperature and low pressure superconductivity.

14.
Sci Rep ; 9(1): 14147, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31578389

RESUMO

As a tightly controlled cell death process, apoptosis eliminates unwanted cells and plays a vital role in multicellular organisms. Previous study have demonstrated that apoptosis occurred in Spodoptera frugiperda cultured Sf9 cells, which triggered by diverse apoptotic stimuli, including azadirachtin, camptothecin and ultraviolet. Due to its simplicity, high sensitivity and reliable specificity, RT-qPCR has been used widespread for analyzing expression levels of target genes. However, the selection of reference genes influences the accuracy of results profoundly. In this study, eight genes were selected for analyses of their suitability as references for normalizing RT-PCR data in Sf9 cells treated with apoptotic agents. Five algorithms, including NormFinder, BestKeeper, Delta Ct method, geNorm, and RefFinder, were used for stability ranking. Based on comprehensively analysis, the expression stability of selected genes varied in cells with different apoptotic stimuli. The best choices for cells under different apoptosis conditions were listed: EF2 and EF1α for cells treated with azadirachtin; RPL13 and RPL3 for cells treated with camptothecin; EF1α and ß-1-TUB for cells irradiated under ultraviolet; and EF1α and EF2 for combinational analyses of samples. Our results not only facilitate a more accurate normalization for RT-qPCR data, but also provide the reliable assurance for further studies of apoptotic mechanisms under different stimulus in Sf9 cells.


Assuntos
Apoptose/genética , Genes de Insetos , Reação em Cadeia da Polimerase em Tempo Real/normas , Reação em Cadeia da Polimerase Via Transcriptase Reversa/normas , Animais , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Camptotecina/toxicidade , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/genética , Proteínas de Insetos/genética , Limoninas/toxicidade , Fatores de Alongamento de Peptídeos/genética , Padrões de Referência , Proteínas Ribossômicas/genética , Células Sf9 , Spodoptera , Tubulina (Proteína)/genética , Raios Ultravioleta
15.
BMC Genomics ; 20(1): 751, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31623553

RESUMO

BACKGROUND: Massive techniques have been evaluated for developing different pest control methods to minimize fertilizer and pesticide inputs. As "push-pull" strategy utilizes generally non-toxic chemicals to manipulate behaviors of insects, such strategy is considered to be environmentally friendly. "Push-pull" strategy has been extraordinarily effective in controlling stem borers, and the identification of new "pushing" or "pull" components against stem borers could be significantly helpful. RESULTS: In this study, the results of field trapping assay and behavioral assay showed the larvae of C.auricilius, one kind of stem borers, could be deterred by rice plant under tilling stage, its main host crop. The profiles of volatiles were compared between rice plants under two different developmental stages, and α-pinene was identified as a key differential component. The repelling activity of α-pinene against C.auricilius was confirmed by Y-tube olfactometer. For illuminating the olfactory recognition mechanism, transcriptome analysis was carried out, and 13 chemosensory proteins (CSPs) were identified in larvae and 19 CSPs were identified in adult of C.auriciliu, which was reported for the first time in this insect. Among these identified CSPs, 4 CSPs were significantly regulated by α-pinene treatment, and CSP8 showed good binding affinity with α-pinene in vitro. CONCLUSIONS: Overall, C.auricilius could be repelled by rice plant at tilling stage, and our results highlighted α-pinene as a key component in inducing repelling activity at this specific stage and confirmed the roles of some candidate chemosensory elements in this chemo-sensing process. The results in this study could provide valuable information for chemosensory mechanism of C.auricilius and for identification of "push" agent against rice stem borers.


Assuntos
Repelentes de Insetos/metabolismo , Mariposas/fisiologia , Controle Biológico de Vetores/métodos , Doenças das Plantas/prevenção & controle , Compostos Orgânicos Voláteis/metabolismo , Animais , Monoterpenos Bicíclicos/metabolismo , Quimiotaxia/genética , Quimiotaxia/fisiologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Larva/genética , Larva/fisiologia , Mariposas/classificação , Mariposas/genética , Oryza/química , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/parasitologia , Doenças das Plantas/parasitologia , Proteínas de Plantas/genética , Ligação Proteica
16.
J Proteomics ; 206: 103439, 2019 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-31271900

RESUMO

Sex-biased protein is thought to be able to drive the phenotypic differences in males and females in insects. In this study, 1385 and 1727 proteins were identified as differentially accumulated proteins (DAPs) by comparing the protein abundances at pupae stage with those at adult stage in ovary and testis of S.litura, respectively. And among which, 548 DAPs were showed to be expressed in both ovary and testis, and 837 and 1179 proteins were considered as ovary-specific and testis-specific DAPs, respectively. To further identify DAPs related to gonad development and sex dimorphism, a total of 320 DAPs were selected and defined as "proteins of specific interest" based on several selecting criteria. Sex dimorphism is a complex and dynamic developmental progress, and these identified DAPs were suggested to be involved in multiple functions such as organonitrogen compound catabolic process, glycosylation, proteasome, N-Glycan biosynthesis and other reproduction-related processes. Overall, our results highlighted these sexual-biased, gonad development related and sexual dimorphism related DAPs, and their abundance variations along with development were also examined, which could provide important information for their functional analysis in reproduction and potential biomarkers for developing useful strategies against S. litura and other orthologous pests. BIOLOGICAL SIGNIFICANCE: Sex dimorphism entails the differentiation of two sexual functions, resulting in sexually phenotypic differences and leading to the development of female and male morphologies and behaviors. However, sex dimorphism related proteins remain to be identified in many non-model insects. In this study, iTRAQ-based proteomic analysis was applied to examine the variations of protein abundances at pupae stage and adult stage in ovary and testis of S.litura, respectively. Reproduction and sex dimorphism related proteins were further identified as "proteins of specific interest". These identified candidate proteins provided valuable information for their further functional analysis in reproduction and could serve as potential biomarkers for developing useful strategies against S. litura and other orthologous pests.


Assuntos
Ovário/metabolismo , Proteoma/metabolismo , Spodoptera/crescimento & desenvolvimento , Spodoptera/metabolismo , Testículo/metabolismo , Animais , Feminino , Proteínas de Insetos/análise , Proteínas de Insetos/metabolismo , Estágios do Ciclo de Vida/fisiologia , Masculino , Ovário/química , Proteoma/análise , Proteômica , Caracteres Sexuais , Testículo/química
17.
J Hazard Mater ; 376: 29-36, 2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31103596

RESUMO

In response to the potential threats stemming from the constantly increasing consumption of herbicides, bioremediation offers a beneficial technology for reducing the widespread herbicide contamination. In order to facilitate the in-situ degradation of diuron, Arthrobacter globiformis D47 is captured onto a biocompatible carrier to assemble the microorganism-immobilized silkworm excrement (MSE) composites. By characterization, bacterial cells are intensively entrapped in/onto the carriers, showing high survival and stable catalytic degradation of target pollutants. Meanwhile, MES composites display excellent adaptiveness and feasibility under different conditions, and the average half-life of diuron is shortened to 7.69 d in sugarcane field where diuron is regularly sprayed for weed management. Importantly, we assess that the use of MSE may generally boost the overall xenobiotic-degrading ability, likely due to the slight alternation of the diversity and composition of soil microbial communities. Taking together, the presented MSE provides an attractive in situ approach for the efficient diuron removal as well as for the more feasible utilization of various pollutant-degrading microorganisms.


Assuntos
Arthrobacter/metabolismo , Bombyx , Diurona/metabolismo , Fezes/microbiologia , Herbicidas/metabolismo , Microbiota , Poluentes do Solo/metabolismo , Animais , Biodegradação Ambiental , Fezes/química , Saccharum/crescimento & desenvolvimento , Solo/química , Microbiologia do Solo/normas
18.
Pestic Biochem Physiol ; 155: 26-35, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30857624

RESUMO

Harmine, a useful botanical compound, has demonstrated insecticidal activity against some pests. However, harmine's mechanism of action has not been thoroughly elucidated to date. To preliminarily explore harmine's insecticidal mechanisms, the cytotoxicity of harmine against Spodoptera frugiperda Sf9 cells was comprehensively investigated. Our results indicated that harmine induced apoptosis in Sf9 cells, as evidenced by cellular and nuclear morphological changes, DNA laddering and increases in caspase-3-like activities. In addition, activation of the mitochondrial apoptotic pathway by harmine was confirmed by the generation of ROS, opening of mitochondrial permeability transition pores (MPTPs), increase in cytosolic Ca2+, changes in mRNA expression levels of genes involved in the mitochondrial apoptotic pathway and increase and release of Cytochrome c. Furthermore, lysosomal membrane permeabilization, release of cathepsin L from the lysosome into the cytosol and cleavage of caspase-3 were also triggered, which indicated that lysosomes were involved in this physiological process. Moreover, the effect of harmine on DNA topoisomerase I activity was investigated by in vivo and molecular docking experiments. These data not only verified that harmine induced apoptosis via comprehensive activation of the mitochondrial and lysosomal pathways and inhibition of DNA topoisomerase I activity in Sf9 cells but also revealed a mechanism of harmine insecticidal functions for pest control.


Assuntos
DNA Topoisomerases Tipo I/metabolismo , Harmina/farmacologia , Animais , Apoptose/efeitos dos fármacos , Lisossomos/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/metabolismo , Células Sf9 , Spodoptera
19.
Small ; 15(14): e1900299, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30786158

RESUMO

Strongly correlated electronic molecules open the way for strong coupling between charge, spin, and lattice degrees of freedom to enable interdisciplinary fields, such as molecular electronic switches and plasmonics, spintronics, information storage, and superconducting circuits. However, despite exciting computational predictions and promising advantages to prepare flexible geometries, the electron correlation effect in molecules has been elusive. Here, the electron correlation effects of molecular plasmonic films are reported to uncover their coupling of charge, spin, lattice, and orbital for the switchable metal-to-insulator transition under external stimuli, at which the simultaneous transition occurs from the paramagnetic, electrical, and thermal conducting state to the diamagnetic, electrical, and thermal insulating state. In addition, density functional theory calculation and spectroscopic studies are combined to provide the mechanistic understanding of electronic transitions and molecular plasmon resonance observed in molecular conducting films. The self-assembled molecular correlated conductor paves the way for the next generation integrated micro/nanosystems.

20.
Pestic Biochem Physiol ; 154: 67-77, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30765058

RESUMO

The ß-carboline alkaloids are a large group of naturally occurring and synthetic indole alkaloids with remarkable pharmacological properties. Furthermore, these alkaloids have also been reported to be effective agents for controlling many pests and plant pathogenic nematodes. However, studies on these potential insecticidal components are scarce. The previous finding that these bioactive compounds can induce programmed cell death in cancer cell lines provided a new insight for exploration of their toxicological mechanisms on insects. In the present study, the cytotoxicity of five natural harmala alkaloids was measured, and the autophagy-inducing effect was confirmed in the Spodoptera frugiperda Sf9 cultured cell line. The results demonstrated that these alkaloids inhibited the proliferation of Sf9 cells in a dose- and time-dependent manner, and the unsaturated ß-carboline alkaloids, harmine and harmol, exhibited stronger autophagy induction activity based on monodansylcadaverineand LysoTracker Red staining. Many autophagy-related genes were increased after ß-carbolines treatment at the RNA level, and the protein expression of Sf-Atg8 was also confirmed to increase after treatment. In addition, the primary autophagic signaling pathway, the PI3K/Akt/mTOR pathway, was altered during the procedure. Furthermore, experiments with special inhibitors and activators were performed to confirm the effect of ß-carbolines on this pathway. The results suggested that the PI3K/Akt/mTOR pathway primarily regulated harmine-induced autophagy in insect cells, and this finding may potentially benefit the application of these promising bioactivity components.


Assuntos
Alcaloides/farmacologia , Autofagia/efeitos dos fármacos , Carbolinas/farmacologia , Fosfatidilinositol 3-Quinases/fisiologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Serina-Treonina Quinases TOR/fisiologia , Animais , Células Sf9 , Transdução de Sinais/efeitos dos fármacos , Spodoptera
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