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1.
Nucleic Acids Res ; 50(8): 4246-4257, 2022 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-35412611

RESUMO

Ligand-Induced duplex-quadruplex transition within the c-MYC promoter region is one of the most studied and advanced ideas for c-MYC regulation. Despite its importance, there is a lack of methods for monitoring such process in cells, hindering a better understanding of the essence of c-MYC G-quadruplex as a drug target. Here we developed a new fluorescent probe ISCH-MYC for specific c-MYC G-quadruplex recognition based on GTFH (G-quadruplex-Triggered Fluorogenic Hybridization) strategy. We validated that ISCH-MYC displayed distinct fluorescence enhancement upon binding to c-MYC G-quadruplex, which allowed the duplex-quadruplex transition detection of c-MYC G-rich DNA in cells. Using ISCH-MYC, we successfully characterized the induction of duplex to G-quadruplex transition in the presence of G-quadruplex stabilizing ligand PDS and further monitored and evaluated the altered interactions of relevant transcription factors Sp1 and CNBP with c-MYC G-rich DNA. Thus, our study provides a visualization strategy to explore the mechanism of G-quadruplex stabilizing ligand action on c-MYC G-rich DNA and relevant proteins, thereby empowering future drug discovery efforts targeting G-quadruplexes.


Assuntos
Quadruplex G , Proteínas Proto-Oncogênicas c-myc , DNA/química , DNA/genética , Ligantes , Hibridização de Ácido Nucleico , Proteínas Proto-Oncogênicas c-myc/química , Proteínas Proto-Oncogênicas c-myc/genética
2.
Chem Biodivers ; 21(2): e202301958, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38130145

RESUMO

Three novel diterpenoid alkaloids, comprising two C19 -diterpenoid alkaloids (1 and 2) and one C20 -diterpenoid alkaloid (3), were isolated from Delphinium ajacis, alongside the six known compounds (4-9). Their structures were elucidated by spectroscopic methods (MS, UV, IR, 1D and 2D NMR) and chemical properties. Simultaneously, the anti-inflammatory properties of all compounds (1-9) was conducted, focusing on nitric oxide (NO) production in LPS-induced BV-2 cells. The results indicated compounds 1-3, 7, and 8 have potential anti-inflammatory activity.


Assuntos
Alcaloides , Delphinium , Diterpenos , Delphinium/química , Espectroscopia de Ressonância Magnética , Alcaloides/farmacologia , Alcaloides/química , Diterpenos/farmacologia , Diterpenos/química , Anti-Inflamatórios/farmacologia , Estrutura Molecular
3.
Carcinogenesis ; 44(6): 463-475, 2023 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-37158456

RESUMO

Circular RNAs (circRNAs) have been accepted to play key roles in the development and progression of mutiple cancers including colorectal cancer (CRC). Here, we identified circ-METTL9, derived from 2 to 4 exons of METTL9 gene, may promote CRC progression by accelerating cell cycle progression. However, the role and mechanism of circ-METTL9 in CRC remains unclear. Based on our data, the expression of circ-METTL9 was significantly upregulated in CRC tissues and markedly increased in advanced tumors in CRC patients. Functional experiments demonstrated that circ-METTL9 overexpression promoted CRC cells proliferation and migration in vitro, and simultaneously enhanced CRC tumor growth and metastasis in vivo. Mechanistically, RNA immunoprecipitation (RIP) assays proved that circ-METTL9 might be a miRNA sponge, and RNA pulldown assays showed the interaction between circ-METTL9 and miR-551b-5p. Notably, cyclin-dependent kinase 6 (CDK6), a key regulator in cell cycle, is a conserved downstream target of miR-551b-5p. Taken together, our findings highlight a novel oncogenic function of circ-METTL9 in CRC progression via circ-METTL9/miR-551b-5p/CDK6 axis, which may serve as a prognostic biomarker and therapeutic target for CRC patients.


Assuntos
Neoplasias Colorretais , MicroRNAs , Humanos , Linhagem Celular Tumoral , Proliferação de Células/genética , Neoplasias Colorretais/patologia , Quinase 6 Dependente de Ciclina/genética , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Circular/genética , RNA Circular/metabolismo , Metiltransferases/metabolismo
4.
Biomarkers ; 28(6): 519-530, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37382580

RESUMO

INTRODUCTION: Atrial fibrillation (AF) is a common cardiac arrhythmia that is associated with heart failure and stroke, leading sometimes to death. But the pathogenesis of AF remains unclear. Numerous studies have investigated whether the connexin 40 (Cx40) polymorphisms influences the risk of AF, but the results are controversial. METHODS: We searched English and Chinese databases and calculated the odds ratio (OR) and 95% confidence interval (CI) to examine the existence of genetic associations between the Cx40 polymorphisms and the risk of AF. All relevant studies were screened and meta-analyzed using Review Manager 5.0. RESULTS: A total of 12 studies, including 10 studies for -44 polymorphism (rs35594137) and 4 studies for -26 polymorphism (rs10465885), were identified for the meta-analysis. For -44 polymorphism, the results showed a significantly increased risk of AF in the five genetic models in the overall analysis. Furthermore, in subgroup analysis, increased AF risks were also observed in Asian and non-Asian populations. For -26 polymorphism, the overall OR revealed an increased risk of AF in dominant model. In subgroup analysis, increased AF risk was only found in recessive genetic model of the Asian population. CONCLUSIONS: The Cx40 polymorphisms were positively associated with AF in both populations, especially on -44 polymorphism.


Assuntos
Fibrilação Atrial , Conexinas , Humanos , Fibrilação Atrial/complicações , Conexinas/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Proteína alfa-5 de Junções Comunicantes
5.
Mol Cell ; 57(3): 492-505, 2015 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-25557548

RESUMO

Treslin helps to trigger the initiation of DNA replication by promoting integration of Cdc45 into the replicative helicase. Treslin is a key positive-regulatory target of cell-cycle control mechanisms; activation of Treslin by cyclin-dependent kinase is essential for the initiation of replication. Here we demonstrate that Treslin is also a critical locus for negative regulatory mechanisms that suppress initiation. We found that the checkpoint-regulatory kinase Chk1 associates specifically with a C-terminal domain of Treslin (designated TRCT). Mutations in the TRCT domain abolish binding of Chk1 to Treslin and thereby eliminate Chk1-catalyzed phosphorylation of Treslin. Significantly, abolition of the Treslin-Chk1 interaction results in elevated initiation of chromosomal DNA replication during an unperturbed cell cycle, which reveals a function for Chk1 during a normal S phase. This increase is due to enhanced loading of Cdc45 onto potential replication origins. These studies provide important insights into how vertebrate cells orchestrate proper initiation of replication.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Replicação do DNA , Proteínas Quinases/metabolismo , Proteínas de Xenopus/metabolismo , Xenopus laevis/metabolismo , Animais , Sítios de Ligação , Proteínas de Ciclo Celular/genética , Linhagem Celular Tumoral , Quinase 1 do Ponto de Checagem , Cromossomos/metabolismo , Células HEK293 , Humanos , Fosforilação , Proteínas de Xenopus/genética , Xenopus laevis/embriologia , Xenopus laevis/genética
6.
Pestic Biochem Physiol ; 191: 105341, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36963923

RESUMO

Phytic acid (PA) is a new substitutable plant-derived antifungal agent; however, few reports have been published regarding its antifungal effects on pathogenic fungi. The present study explored the in vitro antifungal activity of PA against four phytopathogenic fungi and found that PA was the most effective at inhibiting the growth of Fusarium oxysporum. This study aimed to investigate the in vivo and in vitro antifungal activities of PA against the seedling blight of Pinus sylvestris var. mongolica caused by F. oxysporum and to determine its possible mechanism of action. The results showed that PA inhibited spore germination and mycelial growth of F. oxysporum in a concentration-dependent manner and exhibited strong inhibition when its concentration exceeded 1000 mg/L. It mainly destroyed the integrity of the cell membrane, increasing its cell membrane permeability, causing the cell contents to spill out, and impairing fungal growth. In addition, the leakage of intercellular electrolytes and soluble proteins indicated that PA used at its EC20 and EC50 increased the membrane permeability of F. oxysporum. The increase in malondialdehyde and hydrogen peroxide content confirmed that PA treatment at its EC20 and EC50 damaged the cell membrane of the pathogen. Scanning electron microscopy revealed that PA affected the morphology of mycelia, causing them to shrivel, distort, and break. Furthermore, PA significantly reduced the activities of the antioxidant-related enzymes superoxide dismutase and catalase, as well as that of the pathogenicity-related enzymes polygalacturonase, pectin lyase, and endoglucanase (EG) in F. oxysporum (P < 0.05). In particular, EG enzyme activity was maximally inhibited in F. oxysporum treated with PA at its EC50. Moreover, PA significantly inhibited the incidence of disease, and growth indices in Pinus sylvestris var. mongolica seedling blight was determined. In summary, PA has a substantial inhibitory effect on F. oxysporum. Therefore, PA could serve as a new substitutable plant-derived antifungal agent for the seedling blight of P. sylvestris var. mongolica caused by F. oxysporum.


Assuntos
Fusarium , Pinus sylvestris , Pinus sylvestris/microbiologia , Pinus sylvestris/fisiologia , Plântula , Antifúngicos/farmacologia , Ácido Fítico/farmacologia
7.
Chem Biodivers ; 20(9): e202301024, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37507844

RESUMO

One new fawcettimine-type alkaloid (1), one new miscellaneous-type alkaloid (2), four new lycodine-type alkaloids (3-6), and eight known ones (7-14) were isolated from the whole plants of Huperzia serrata. Their structures and absolute configurations were elucidated based on spectroscopic data, X-ray diffraction, ECD calculation and Mosher's method. Compound 1 was a rare C18 N2 -type Lycopodium alkaloid, possessing serratinine skeleton with an amide side chain in C-5. The absolute configuration of the 18-OH of compounds 4-6 were first determined by Mosher's method. Moreover, compounds 1-14 were assayed anti-acetylcholinesterase effect in vitro, and compound 7 showed significant anti-acetylcholinesterase activity with an IC50 value of 16.18±1.64 µM.


Assuntos
Alcaloides , Huperzia , Lycopodium , Acetilcolinesterase , Alcaloides/farmacologia , Alcaloides/química , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/química , Huperzia/química , Lycopodium/química , Estrutura Molecular
8.
Pestic Biochem Physiol ; 181: 105012, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35082035

RESUMO

Due to its biological activity, carvacrol (CAR) is widely used in medicine, agriculture, and forestry. Our previous studies showed that in Lymantria dispar larvae, CAR treatment can induce the production of antifeedants and lead to growth inhibition and death of larvae. However, the effect CAR exerts on RNA levels in L. dispar larvae remains unclear. In this study, the Illumina HiSeq4000 sequencing platform was used to sequence the total RNA of L. dispar larvae. A total of six cDNA libraries (three treatments and three controls) were established and 39,807 genes were generated. Compared with the control group, 296 differentially expressed genes (DEGs) (142 up-regulated and 154 down-regulated) were identified after CAR treatment. GO and KEGG enrichment analyses showed that these DEGs mainly clustered in the metabolism of xenobiotics, carbohydrates, and lipids. Furthermore, 12 DEGs were found to be involved in detoxification, including six cytochrome P450s, two esterases, one glutathione peroxidase, one UDP-glycosyltransferase gene, and two genes encoding heat shock proteins. The expression levels of detoxification genes changed under CAR treatment (especially P450s), which further yielded candidate genes for explorations of the insecticidal mechanism of CAR. The reliability of transcriptome data was verified by qRT-PCR. The enzyme activities of CYP450 and acid phosphatase significantly increased (by 38.52 U/mg·prot and 0.12 µmol/min·mg, respectively) 72 h after CAR treatment. However, the activity of alkaline phosphatase did not change significantly. These changes in enzyme activity corroborated the reliability of the transcriptome data at the protein level. The results of GO enrichment analysis of DEGs indicated that CAR influenced the oxidation-reduction process in L. dispar larvae. Furthermore, CAR can cause oxidative stress in L. dispar larvae, identified through the determination of peroxidase and polyphenol oxidase activities, total antioxidant capacity, and hydrogen peroxide content. This study provides useful insight into the insecticidal mechanism of CAR.


Assuntos
Mariposas , Transcriptoma , Animais , Cimenos , Perfilação da Expressão Gênica , Larva/genética , Mariposas/genética , Reprodutibilidade dos Testes
9.
Entropy (Basel) ; 24(10)2022 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37420434

RESUMO

In this paper, we present the multi-stage attentive network (MSAN), an efficient and good generalization performance convolutional neural network (CNN) architecture for motion deblurring. We build a multi-stage encoder-decoder network with self-attention and use the binary cross-entropy loss to train our model. In MSAN, there are two core designs. First, we introduce a new attention-based end-to-end method on top of multi-stage networks, which applies group convolution to the self-attention module, effectively reducing the computing cost and improving the model's adaptability to different blurred images. Secondly, we propose using binary cross-entropy loss instead of pixel loss to optimize our model to minimize the over-smoothing impact of pixel loss while maintaining a good deblurring effect. We conduct extensive experiments on several deblurring datasets to evaluate the performance of our solution for deblurring. Our MSAN achieves superior performance while also generalizing and compares well with state-of-the-art methods.

10.
Biotechnol Bioeng ; 118(10): 3744-3759, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34110008

RESUMO

Multispecific antibodies, often composed of three to five polypeptide chains, have become increasingly relevant in the development of biotherapeutics. These molecules have mechanisms of action that include redirecting T cells to tumors and blocking multiple pathogenic mediators simultaneously. One of the major challenges for asymmetric multispecific antibodies is generating a high proportion of the correctly paired antibody during production. To understand the causes and effects of chain mispairing impurities in a difficult to express multispecific hetero-IgG, we investigated consequences of individual and pairwise chain expression in mammalian transient expression hosts. We found that one of the two light chains (LC) was not secretion competent when transfected individually or cotransfected with the noncognate heavy chain (HC). Overexpression of this secretion impaired LC reduced cell growth while inducing endoplasmic reticulum stress and CCAAT/enhancer-binding protein homologous protein (CHOP) expression. The majority of this LC was observed as monomer with incomplete intrachain disulfide bonds when expressed individually. Russell bodies (RB) were induced when this LC was co-expressed with the cognate HC. Moreover, one HC paired promiscuously with noncognate LC. These results identify the causes for the low product quality observed from stable cell lines expressing this heteroIgG and suggest mitigation strategies to improve overall process productivity of the correctly paired multispecific antibody. The approach described here provides a general strategy for identifying the molecular and cellular liabilities associated with difficult to express multispecific antibodies.


Assuntos
Anticorpos Biespecíficos , Expressão Gênica , Engenharia de Proteínas , Animais , Anticorpos Biespecíficos/biossíntese , Anticorpos Biespecíficos/genética , Células CHO , Cricetulus , Cabras , Células HEK293 , Humanos , Cadeias Leves de Imunoglobulina/biossíntese , Cadeias Leves de Imunoglobulina/genética , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética
11.
Bioorg Chem ; 116: 105337, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34521046

RESUMO

A phytochemical investigation on the alkaloids from water-soluble part of Sophora alopecuroides led to obtain forty matrine-type alkaloids (1-40) including eighteen new ones (1-18), which covers almost all positions of the oxygen substitution in matrine-type structure. Notably, eight compounds (1-8) belong to rare bis-amide matrine-type alkaloid. The new structures were determined based on extensive spectroscopic data, electronic circular dichroism (ECD) calculations, and six instances, verified by X-ray crystallography. Most of isolates showed anti-neuroinflammatory activities based on the expression of tumor necrosis factor (TNF)-α and interleukin (IL)-6 in BV2 microglia cells. Especially, compound 39 can suppress those two mediator secretions in a dose-dependent manner with IC50 values of 21.6 ± 0.5 and 16.7 ± 0.8 µM, respectively. Further mechanistic study revealed that 39 suppressed the phosphorylation of IκBα and p65 subunit to regulate the NF-κB signaling pathway.


Assuntos
Alcaloides/farmacologia , Anti-Inflamatórios/farmacologia , Quinolizinas/farmacologia , Sophora/química , Alcaloides/química , Alcaloides/isolamento & purificação , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Linhagem Celular , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Interleucina-6/antagonistas & inibidores , Interleucina-6/metabolismo , Camundongos , Modelos Moleculares , Estrutura Molecular , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Quinolizinas/química , Quinolizinas/isolamento & purificação , Sementes/química , Transdução de Sinais/efeitos dos fármacos , Solubilidade , Relação Estrutura-Atividade , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/metabolismo , Água/química , Matrinas
12.
Cell Mol Life Sci ; 77(22): 4709-4723, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31925452

RESUMO

AIMS: Endocannabinoids are lipid mediators involved in the regulation of glucose homeostasis. They interact with the canonical cannabinoid receptors CB1 and CB2, and it is now apparent that some cannabinoid receptor ligands are also agonists at GPR55. Thus, CB1 antagonists such as SR141716A, also known as rimonabant, and AM251 act as GPR55 agonists in some cell types. The complex pharmacological properties of cannabinoids make it difficult to fully identify the relative importance of CB1 and GPR55 in the functional effects of SR141716A, and AM251. Here, we determine whether SR141716A and AM251 regulation of mouse and human islet function is through their action as GPR55 agonists. METHODS: Islets isolated from Gpr55+/+ and Gpr55-/- mice and human donors were incubated in the absence or presence of 10 µM SR141716A or AM251, concentrations that are known to activate GPR55. Insulin secretion, cAMP, IP1, apoptosis and ß-cell proliferation were quantified by standard techniques. RESULTS: Our results provide the first evidence that SR141716A and AM251 are not GPR55 agonists in islets, as their effects are maintained in islets isolated from Gpr55-/- mice. Their signalling through Gq-coupled cascades to induce insulin secretion and human ß-cell proliferation, and protect against apoptosis in vitro, indicate that they have direct beneficial effects on islet function. CONCLUSION: These observations may be useful in directing development of peripherally restricted novel therapeutics that are structurally related to SR141716A and AM251, and which potentiate glucose-induced insulin secretion and stimulate ß-cell proliferation.


Assuntos
Canabinoides/metabolismo , Ilhotas Pancreáticas/efeitos dos fármacos , Piperidinas/farmacologia , Pirazóis/farmacologia , Receptores de Canabinoides/metabolismo , Rimonabanto/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Proliferação de Células/efeitos dos fármacos , Endocanabinoides/metabolismo , Feminino , Humanos , Insulina , Secreção de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Ligantes , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Receptores Acoplados a Proteínas G/metabolismo
13.
Curr Microbiol ; 78(9): 3562-3576, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34347145

RESUMO

Verticillium wilt is a major disease of cotton that considerably decreases yield and crop quality. Soil microbial communities play an important role in plant health. Therefore, biocontrol bacteria that regulate microbial communities in rhizosphere soil can improve plant resistance to pathogens. Previously, the antagonistic strain Bacillus axarquiensis TUBP1 was screened and found to act against Verticillium dahliae with 43% biocontrol effect in cotton fields. We studied the effect of Bacillus axarquiensis TUBP1 with a green fluorescent protein (GFP) gene marker on the microbial community structure of cotton rhizosphere soil and cotton yield and quality. Cotton Verticillium wilt incidence, soil biochemical properties, and soil bacterial and fungal communities were analyzed. Results showed that bacterial and fungal abundance in cotton rhizosphere soil was temporarily changed after applying B. axarquiensis TUBP-315GFP. However, Bacillus significantly increased, whereas V. dahliae significantly decreased. The incidence of cotton Verticillium wilt after treatment with B. axarquiensis TUBP-315GFP was significantly lower and cotton production increased by 40.6%. Our findings indicated that the application of B. axarquiensis TUBP-315GFP can change microbial community structure of cotton rhizosphere soil, leading to a reduction in the incidence of cotton Verticillium wilt and increasing cotton yield.


Assuntos
Bacillus , Microbiota , Verticillium , Ascomicetos , Bacillus/genética , Proteínas de Fluorescência Verde , Incidência , Doenças das Plantas , Rizosfera , Solo
14.
Pestic Biochem Physiol ; 175: 104859, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33993955

RESUMO

Vanillin is a natural antimicrobial agent; however, there are few reports on its antifungal effect on postharvest pathogenic fungi. This study aimed to investigate the in vivo and in vitro antifungal activities of vanillin against gray mold (caused by B. cinerea) and black rot (caused by A. alternata) of cherry tomato fruit and to explain its possible mechanism of action. Vanillin strongly inhibits Botrytis cinerea and Alternaria alternata mycelial growth, spore germination, and germ tube elongation in a concentration-dependent manner (P<0.05). In vivo experiments showed that 4000 mg L-1 vanillin treatment inhibited cherry tomato gray mold and black rot occurrence. Besides, intercellular electrolytes, soluble proteins, and soluble sugars leakage indicated that 50 or 100 mg L-1 vanillin treatment increased Botrytis cinerea and Alternaria alternata membrane permeability. The increase of malondialdehyde and hydrogen peroxide contents confirmed that 50 or 100 mg L-1 vanillin treatment damages the pathogen membranes. Importantly, vanillin treatment inhibited the pathogenicity-related enzyme activities of the two pathogens to reduce their infection ability, among them PL enzyme activity in A. alternata was most inhibited, reducing by 94.7 % at 6 h treated with 100 mg L-1 vanillin. The hyphae morphology of the two pathogens changed, the mycelia were severely damaged, and the hyphae surface was deformed, shrunk, or even broken after 100 mg L-1 vanillin treatment. In summary, vanillin had a substantial inhibitory effect on postharvest gray mold and black rot in cherry tomato fruit. Therefore, vanillin can be an effective alternative to prevent and control cherry tomato postharvest diseases.


Assuntos
Solanum lycopersicum , Alternaria , Benzaldeídos , Botrytis , Frutas , Doenças das Plantas
15.
J Asian Nat Prod Res ; 23(4): 399-406, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32319324

RESUMO

A new sesquiterpene pyridine alkaloid (1), along with four known compounds (2-5), were isolated from the stems and leaves of Euonymus fortunei. The new structure was determined by extensive spectroscopic analyses (IR, UV, NMR, HRESIMS and ECD). In addition, compound 3 showed a stronger anti-respiratory syncytial virus (RSV) activity with an IC50 value of 1.20 ± 0.10 µM than the positive control ribavirin with an IC50 value of 5.62 ± 0.49 µM.[Formula: see text].


Assuntos
Alcaloides , Euonymus , Sesquiterpenos , Estrutura Molecular , Folhas de Planta , Piridinas
16.
Arch Insect Biochem Physiol ; 104(3): e21676, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32323892

RESUMO

The gut microbiota plays an important role in pheromone production, pesticide degradation, vitamin synthesis, and pathogen prevention in the host animal. Therefore, similar to gut morphology and digestive enzyme activity, the gut microbiota may also get altered under plant defensive compound-induced stress. To test this hypothesis, Dendrolimus superans larvae were fed either aconitine- or nicotine-treated fresh leaves of Larix gmelinii, and Lymantria dispar larvae were fed either aconitine- or nicotine-treated fresh leaves of Salix matsudana. Subsequently, the larvae were sampled 72hr after diet administration and DNA extracted from larval enteric canals were employed for gut microbial 16S ribosomal RNA gene sequencing (338 F and 806 R primers). The sequence analysis revealed that dietary nicotine and aconitine influenced the dominant bacteria in the larval gut and determined their abundance. Moreover, the effect of either aconitine or nicotine on D. superans and L. dispar larvae had a greater dependence on insect species than on secondary plant metabolites. These findings further our understanding of the interaction between herbivores and host plants and the coevolution of plants and insects.


Assuntos
Aconitina/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Mariposas/microbiologia , Nicotina/farmacologia , Animais , Bactérias/classificação , Bactérias/genética , Larix , Larva/efeitos dos fármacos , Larva/microbiologia , Mariposas/efeitos dos fármacos , Mariposas/crescimento & desenvolvimento , Folhas de Planta , RNA Ribossômico 16S , Salix
17.
Arch Insect Biochem Physiol ; 104(3): e21691, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32410326

RESUMO

In the present study, diel pattern in gut microbial communities in insects were evaluated. Lymantria dispar asiatica fourth instar larvae (72 ± 2 hr after molting) at noon (LdD) and midnight (LdN) were used for a comparative analysis of the gut microbial community. Ten bacterial operational taxonomic units (OTUs) were shared between LdD and LdN samples. One bacterial OTU was specific to LdD. The dominant gut microbes were OTU72 in LdD and OTU75 in LdN. A linear discriminant analysis effect size cladogram suggested that ten bacterial OTUs maintain significant differences in relative abundances between LdD and LdN. These results agreed with the discrete ellipses between LdD and LdN in principal coordinates analysis plots. Additionally, using phylogenetic investigation of communities by reconstruction of unobserved states, the gut microbial community was assigned to 23 functional terms, among which 22 exhibited significant differences between LdD and LdN. To conclude, the present study documented a diel pattern in the gut microbial community of L. dispar asiatica larvae.


Assuntos
Ritmo Circadiano , Microbioma Gastrointestinal/fisiologia , Mariposas/microbiologia , Animais , Bactérias/classificação , Larva/microbiologia , Mariposas/crescimento & desenvolvimento , Filogenia
18.
Arch Insect Biochem Physiol ; 103(4): e21654, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31916310

RESUMO

To study dietary pH effects on Lymantria dispar asiatica larvae and provide a theoretical basis for its control in different forests, phosphate buffers (PBs) of pH 6, 7, and 8 were used to prepare experimental diets. The diet prepared with pH 6 PB was named as DPB6, with pH 8 PB as DPB8, and with pH 7 PB as DPB7 (control). The dietary pH was 5.00 in DPB6, 6.05 in control, and 6.50 in DPB8. After feeding on the diets with different pH values for 84 hr, fourth-instar caterpillars were randomly collected. Growth and various physiological traits were determined and 16S recombinant DNA sequencing was performed using the intestinal microflora of surviving larvae. Results showed that the mortality was 30% in DPB6, and 10% in DPB8, while no mortality was observed in control. The partial least squares discriminant analyses suggested that diets prepared with PB of different pH resulted in different food intake, amount of produced feces, weight gain, digestive enzyme activities, and antioxidant enzyme activities in larvae. Interestingly, both the highest weight gain and the lowest total antioxidant capacities were seen in control larvae. Results also showed that the larval gut microbiota community structure was significantly affected by dietary pH. Moreover, linear discriminant analysis effect size suggested that the family Acetobacteraceae in control, genus Prevotella in DPB8, and genus Lactococcus, family Flavobacteriaceae, family Mitochondria, and family Burkholderiaceae in DPB6 contributed to the diversity of the larval gut microbial community.


Assuntos
Ração Animal/análise , Microbioma Gastrointestinal/efeitos dos fármacos , Mariposas/crescimento & desenvolvimento , Mariposas/microbiologia , Animais , Dieta , Concentração de Íons de Hidrogênio , Larva/crescimento & desenvolvimento , Larva/microbiologia
19.
Pestic Biochem Physiol ; 169: 104639, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32828363

RESUMO

Sodium pheophorbide a (SPA) is a new alternative fungicide with low toxicity and high efficiency, which has high fungicidal activity against Pestalotiopsis neglecta, a pathogen that causes black spot needle blight of Pinus sylvestris var. mongolica. To utilize SPA for plant disease control, understanding its antifungal mechanism is essential. Six cDNA libraries were constructed from 3 d-old P. neglecta mycelia (three SPA-infected and three untreated groups) and 29,850 expressed genes were obtained by Illumina HiSeq4000 sequencing. Compared with controls, 3268 differentially expressed genes (DEGs) were identified in SPA-treated groups, including 1879 upregulated and 1389 downregulated genes. Most DEGs were involved in the metabolism of amino acids, carbohydrates, and lipids, as well as cell structure and genetic information processing. These findings were further confirmed by decreased conductivity, RNA and protein content, and activities of nicotinamide adenine dinucleotide-dependent malate dehydrogenase, citrate synthase, isocitrate dehydrogenase, and succinate dehydrogenase. Moreover, qRT-PCR verified the reliability of the transcriptome results. After treatment with SPA at different concentrations for 60 min, the expressions of three cell wall degrading enzyme-related genes (PnEG, PnBG, and PnPG) were all suppressed. Overall, this study provided insights into the molecular mechanisms through which SPA inhibits P. neglecta, increasing the possibility of developing SPA into an effective fungicide in the future.


Assuntos
Sódio , Transcriptoma , Parede Celular , Clorofila/análogos & derivados , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Reprodutibilidade dos Testes
20.
Pestic Biochem Physiol ; 164: 196-202, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32284127

RESUMO

Lymantria dispar asiatica is a globally distributed herbivorous pest. Avermectin is a highly effective, broad-spectrum insecticide. In this study, fourth instar L. dispar asiatica larvae were exposed to a LC30 dose of avermectin. The structure and function of larval gut microbial community was analyzed to examine how gut microbiota in L. dispar asiatica larvae responded to avermectin stress. Results showed that the structure and function of gut microbial community in L. dispar asiatica larvae were varied by avermectin stress. To be precise, more than half quantity of the observed Optical Taxonomic Units (OTUs) showed significantly different abundances under avermectin stress. Linear discriminant analysis effect size (LEfSe) suggested nine bacterial genera and 12 fungal genera contributed to the different gut microbial community structure in L. dispar asiatica larvae. Gut microbial function classification (PICRUSt and FUNGuild) suggested that three bacterial function categories and a fungal function guild were significantly increased, and two fungal function guilds were significantly decreased by avermectin stress. This study furthers our understanding of the physiology of L. dispar asiatica larvae under avermectin stress, and is an essential step towards future development of potential pesticide targets.


Assuntos
Inseticidas , Lepidópteros , Mariposas , Animais , Ivermectina/análogos & derivados , Larva
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