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1.
Front Microbiol ; 14: 1162113, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37275152

RESUMO

The brown planthopper (BPH), Nilaparvata lugens, is one of the most destructive pests of rice. Given the threats posed by insecticide resistance to its control, eco-friendly strategies based on microbial pathogens emerged as a promising biocontrol alternative. In the present study, we isolated a native fungal pathogen against BPH from infected BPH cadavers and preliminarily identified as a strain of Aspergillus fumigatus based on morphological and molecular methods. Laboratory bioassay revealed that this fungal strain was highly virulent to BPH both at nymphal and adult stages, with the median lethal times (LT50) of 7.5 and 5.8 days under high conidial concentration of 1 × 109 conidia mL-1. A genome-wide view of gene expressions in BPH against fungal attack was analyzed by transcriptomic sequencing and consequently a large number of differentially expressed genes that mainly involved in host immune defense and cell detoxification were found. RNAi-mediated knockdown of an upregulated gene encoding a serine protease (NlSPN) could cause a significant decrease in BPH survival. Combination of dsRNA injection and fungal infection showed an additive effect on BPH mortality, which provided clues to develop new pest management strategies against BPH.

2.
Foods ; 12(23)2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38231780

RESUMO

Low-cost fish species are often used to adulterate or substitute for Atlantic salmon products, posing a serious threat to market order and public health. Hence, reliable techniques are urgently needed to detect Atlantic salmon adulteration. In this study, a precise method for identifying and quantifying adulterated Atlantic salmon with rainbow trout based on droplet digital PCR (ddPCR) testing was developed. Species-specific primers and probes were designed targeting the single-copy nuclear gene myoglobin of two salmonids. A quantitative formula for calculating the mass fraction of adulterated Atlantic salmon with rainbow trout was established based on a one-step conversion strategy, in which the DNA copy number ratios were directly transformed to meat mass fractions by introducing a fixed constant (the transfer coefficient). The dynamic range of the established ddPCR method was from 1% to 90%, with a limit of detection (LOD) of 0.2% and a limit of quantification (LOQ) of 0.8% for rainbow trout in Atlantic salmon, respectively. The quantification method demonstrated an acceptable level of repeatability and reproducibility, as the values of the relative standard deviation (RSD) for the tested meat mixtures with the known fractions were all less than 5%. Thermal and freezing treatments, as well as adding food additives within the recommended dosage limits, had no significant effect on the quantification accuracy. The method was successfully applied to detect rainbow trout adulteration in commercial raw and processed Atlantic salmon products. In comparison to real-time quantitative PCR (qPCR) testing, the established ddPCR method exhibited a higher level of stability and accuracy. Overall, the ddPCR-based quantitative method exhibited high levels of accuracy, stability, sensitivity, and practicability, suitable for applications in the routine surveillance and quality assurance of salmon products.

3.
Pest Manag Sci ; 77(11): 4903-4914, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34171165

RESUMO

BACKGROUND: The brown planthopper (BPH) is one of the most destructive pests of rice, causing tremendous yield and economic losses every year. The fungal entomopathogen Metarhizium anisopliae was previously proved to have great potential for BPH biocontrol. Genome-wide insight into the insect-fungus interaction is crucial for genetic improvement of M. anisopliae to enhance its virulence to BPH but still has been poorly explored. RESULTS: Using dual RNA-seq approach, we present here a global view of host and fungal gene expressions in BPH adults during the fungal infection. The results revealed that BPH could initiate strong defense responses against the fungal attack by upregulating the expressions of a large number of genes, including genes involved in cuticle formation, immune response, cell detoxification and biomacromolecule metabolism. Correspondingly, the fungal entomopathogen could induce a series of genes to infect and modulate BPH, including genes involved in fungal penetration, invasive growth, stress resistance and virulence. Three host defense-related genes (NlPCE4, NlPOD1 and NlCYP4DE1) were chosen for further function analysis. RNAi-mediated knockdown of NlPCE4 caused a significant decrease in BPH survival, but no obvious effects on the survival rates were detected by the suppression of NlPOD1 and NlCYP4DE1. Combination of dsRNA injection and fungal infection could significantly enhance the BPH-killing speed, as synergistic mortalities were observed in co-treatments of RNAi and M. anisopliae infection. CONCLUSION: Our study provides a comprehensive insight into molecular mechanisms of host-pathogen interaction between BPH and M. anisopliae and contributes to future development of new efficient biocontrol strategies for BPH biocontrol.


Assuntos
Hemípteros , Metarhizium , Oryza , Animais , Hemípteros/genética , Interações Hospedeiro-Patógeno/genética , Metarhizium/genética , Oryza/genética , Análise de Sequência de RNA
4.
J Econ Entomol ; 114(2): 937-946, 2021 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-33459777

RESUMO

Microbiome associated with insects play vital roles in host ecology and physiology. The small brown planthopper (SBPH), Laodelphax striatellus, is a polyphagous insect pest that caused enormous damage to a wide range of cereal crops. Previous studies have assessed the effects of environmental factors, such as antibiotics, insecticide, and geographical habitat on the bacterial composition of SBPH. However, the influence of host plants on the microbial community in SBPH still unclear. Here, we characterized and compared the microbial community in three SBPH populations feeding on rice, barley, and wheat, respectively, using high-throughput amplicon sequencing. Our observations revealed that the microbiome harbored by SBPH was abundant and diverse. Ten phyla comprising 141 genera of bacteria were annotated, and four fungal phyla consisting of 47 genera were assigned. The bacteria belonging to the phylum Proteobacteria were the most prevalent and the fungi with the highest abundance were from the order Hypocreales. Comparative analysis showed that host plants could significantly induce structural changes of SBPH microbiome. Significant differences in abundance were observed in two main bacterial orders (Rickettsiales and Rhodospirillales) and three fungal classes (Sordariomycetes, an unclassified class in Ascomycota and Eurotiomycetes) among three host-adapted SBPH populations. Our results could broaden our understanding of interactions among SBPH, its microbial associates and host plants, and also represented the basis of future SBPH biological management.


Assuntos
Hemípteros , Microbiota , Oryza , Animais , Bactérias/genética , Fungos
5.
Arch Microbiol ; 203(1): 325-333, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32940717

RESUMO

Gut microbiota plays vital roles in the development, evolution and environmental adaptation of the host insects. The brown planthopper (BPH) is one of the most destructive pests of rice, but little is known about its gut microbiota. In this study, we investigated the gut bacterial communities in two BPH populations feeding on susceptible and resistant rice varieties by high-throughput amplicon sequencing. Our results revealed that the gut bacterial communities in BPH were species diverse. A total of 29 phyla and 367 genera were captured, with Proteobacteria and Acinetobacter being the most prominent phylum and genus, respectively. Comparative analysis showed that significant differences in the profile of gut bacterial communities existed between the two BPH populations. The species richness detected in the population feeding on the resistant rice variety was significantly higher than that in the population rearing on the susceptible rice variety. Although the most dominant gut bacteria at all taxonomic levels showed no significant differences between the two BPH populations, the relative abundances of two subdominant phyla (Firmicutes and Bacteroidetes) and two subdominant classes (Bacteroidia and Clostridia) were significantly different. FAPROTAX analysis further indicated that host rice varieties might induce changes of the gut bacterial flora in BPH, as significant differences in five metabolism-related functional categories (fermentation, methylotrophy, xylanolysis, nitrate reduction and ureolysis) were detected between the two BPH populations. Our results are informative for studies which focused on the interactions between BPH and its symbiotic microbes and could also provide the basis of future BPH biological management.


Assuntos
Bactérias , Fenômenos Fisiológicos Bacterianos , Microbioma Gastrointestinal , Hemípteros/microbiologia , Interações Hospedeiro-Patógeno , Oryza/metabolismo , Animais , Bactérias/classificação , Bactérias/genética , Sequenciamento de Nucleotídeos em Larga Escala , Oryza/classificação , Oryza/microbiologia , Simbiose
6.
Kaohsiung J Med Sci ; 37(2): 121-127, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33022894

RESUMO

Cullin 4B (CUL4B) was reported to be closely related to the progression of some tumors, but its function in clear cell renal cell carcinoma (ccRCC) has not been reported. Our present study found CUL4B was upregulated in ccRCC, and CUL4B knockdown markedly inhibited ccRCC cell growth and induced apoptosis. In addition, CUL4B knockdown markedly inhibited antiapoptotic proteins' expression in ccRCC cells, including Mcl-1 and Bcl-2, and silenced CUL4B also induced the cleavages of PARP, an important index of apoptosis. We also confirmed microRNA-217 (miR-217) was downregulated in ccRCC tumor tissues, and negatively correlated with CUL4B expression. Further investigations revealed miR-217 targeted CUL4B and markedly inhibited its expression in ccRCC cells. In addition, overexpression of miR-217 by mimics significantly suppressed ccRCC cell growth. In contrast, enforced expression of CUL4B significantly abolished miR-217-induced cell survival inhibition in ccRCC cells. In conclusion, our present results suggested targeting miR-217-CUL4B axis would be a promising strategy for ccRCC treatment.


Assuntos
Apoptose , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Proteínas Culina/metabolismo , Neoplasias Renais/genética , Neoplasias Renais/patologia , MicroRNAs/metabolismo , Apoptose/genética , Sequência de Bases , Linhagem Celular Tumoral , Proliferação de Células/genética , Sobrevivência Celular/genética , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , MicroRNAs/genética
7.
Inorg Chem ; 59(6): 3894-3904, 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32119529

RESUMO

Commercial white LED devices usually suffer from a high color temperature and poor color rendering. Developing a new, efficient, and stable red phosphor is the key to solving this problem. In this work, a series of pure Ca3Y2-xB4O12:xEu3+ (0 < x ≤ 2) samples, including the new and fully transitional borate phosphor Ca3Eu2B4O12 (CEBO), have been successfully prepared by solid-state reaction synthesis. CEBO is isostructural with Ca3Y2B4O12 (CYBO), belonging to the orthorhombic system with space group Pnma (No. 62). Under optimal 393 nm excitation, this borate exhibits a strong red emission, peaking at 615 nm, with high color purity. Interestingly, the luminescence of CEBO is relatively higher than that of CYBO:Eu3+ phosphors. The quantum yield of this non-concentration-quenching phosphor reaches 95.6%. Furthermore, a warm pc-WLED device has been fabricated by mixing as-prepared CEBO powders and commercial BaMgAl10O17:Eu2+ and (Sr, Ba)2SiO4:Eu2+ phosphors, which exhibits a high color rendering index (Ra = 83.7) along with a color temperature of around 3883 K. The present work indicates that this new borate, with outstanding quantum efficiency and favorable thermal stability, can be used as a red phosphor for application in WLEDs.

8.
Dalton Trans ; 49(10): 3260-3271, 2020 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-32096515

RESUMO

The development of suitable red phosphors to obtain improved white color stands a good chance to serve in the new generation of white light-emitting diodes. Owing to multi-elements via doping and oxidation of reduced valence state of lanthanide or transition metal ions, most of the reported phosphors usually suffer from complex synthetic processes and unstable color of the lighting industry cycle. In this work, we present a new red emitting and stable Sr3Eu2B4O12 phosphor with regard to its special structure. It crystallizes as an orthorhombic cell, with Sr and Eu atoms co-occupying three different lattice sites in the space group of Pnma (no. 62). It is proposed that the long bond distance between activators minimizes the content quenching, while the high disorder of location restricts the thermal quenching. This phosphor emits bright red light with good color purity under UV excitation, with the luminescence intensity and quantum yield tunable via the fabrication temperature. Through a preliminary optimization of the synthesis process, the Sr3Eu2B4O12 phosphor prepared at 1250 °C has high quantum yields of about 94.7% and excellent thermal stability of 85.6% intensity retention at 150 °C relative to the initial value at room temperature. The calculated Judd-Ofelt intensity parameters (Ω2, Ω4) further clarified that the Eu3+ site in Sr3Eu2B4O12 had lower symmetry without an inversion center, and more distorted local environment and structural rigidity of the host, predicting excellent thermal stability. Finally, a warm pc-WLED device has been produced by mixing as-prepared Sr3Eu2B4O12 powders and commercial BaMgAl10O17:Eu2+ and (Sr, Ba)2SiO4:Eu2+ phosphors, which exhibits a high color rendering index (Ra = 83.4) along with a color temperature at around 4102 K. The present work indicates that the Sr3Eu2B4O12 phosphor is an efficient red component with excellent thermal stability for white-light production of near-UV-excited w-LEDs.

9.
Pest Manag Sci ; 76(8): 2589-2600, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32077581

RESUMO

BACKGROUND: To initiate insect infection, entomopathogenic fungi produce diverse cuticle-degrading enzymes. Of those, lipolytic enzymes participate in epicuticular lipid hydrolysis and thus facilitate fungal penetration through the outermost cuticular barrier of the insect host. The Far/CTF1-type zinc finger transcription factors play an important role in the regulation of lipolytic activity and fungal pathogenicity in plant pathogens but remain functionally unknown in fungal insect pathogens. RESULTS: Two Far/CTF1-type transcription factor Bbctf1α and Bbctf1ß, which are essential for differential expression of genes involved in the fungal lipid degradation, were identified and functionally characterized in a fungal entomopathogen Beauveria bassiana. Disruption of each gene led to drastic losses of extracellular lipolytic activities under lipidic substrate-inducing conditions, followed by remarkable phenotypic defects associated with the fungal biocontrol potential. These defects mainly included severe impairments of mycelial growth and conidium formation, and drastic losses of tolerance to the stresses of oxidation and cell wall perturbation during colony growth under either normal or induction conditions. Bioassays showed that the virulence of each disruption mutant on the greater wax moth was remarkably attenuated in topical immersion. However, there was no significant difference in intrahemolymph injection when the cuticle penetration process was bypassed. CONCLUSIONS: Bbctf1α and Bbctf1ß are multifunctional transcription factors that play vital roles in the regulation of fungal lipid utilization and contribute to the vegetative growth, sporulation capacity, environmental fitness and pest control potential in B. bassiana. © 2020 Society of Chemical Industry.


Assuntos
Beauveria , Animais , Proteínas Fúngicas , Regulação Fúngica da Expressão Gênica , Insetos , Lipídeos , Esporos Fúngicos , Fatores de Transcrição , Virulência , Dedos de Zinco
10.
Insect Sci ; 27(5): 883-894, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31612637

RESUMO

The microbiome associated with brown planthopper (BPH) plays an important role in mediating host health and fitness. Characterization of the microbial community and its structure is prerequisite for understanding the intricate symbiotic relationships between microbes and host insect. Here, we investigated the bacterial and fungal communities of BPH at different developmental stages using high-throughput amplicon sequencing. Our results revealed that both the bacterial and fungal communities were diverse and dynamic during BPH development. The bacterial communities were generally richer than fungi in each developmental stage. At 97% similarly, 19 phyla and 278 genera of bacteria were annotated, while five fungal phyla comprising 80 genera were assigned. The highest species richness for the bacterial communities was detected in the nymphal stage. The taxonomic diversity of the fungal communities in female adults was generally at a relatively higher level when compared to other developmental stages. The most dominant phylum of bacteria and fungi at each developmental stage all belonged to Proteobacteria and Ascomycota, respectively. A significantly lower abundance of bacterial genus Acinetobacter was recorded in the egg stage when compared to other developmental stages, while the dominant fungal genus Wallemia was more abundant in the nymph and adult stages than in the egg stage. Additionally, the microbial composition differed between male and female adults, suggesting that the microbial communities in BPH were gender-dependent. Overall, our study enriches our knowledge on the microbial communities associated with BPH and will provide clues to develop potential biocontrol techniques against this rice pest.


Assuntos
Bactérias/isolamento & purificação , Fungos/isolamento & purificação , Hemípteros/microbiologia , Microbiota , Animais , Bactérias/classificação , Feminino , Fungos/classificação , Hemípteros/crescimento & desenvolvimento , Sequenciamento de Nucleotídeos em Larga Escala , Masculino , Ninfa/crescimento & desenvolvimento , Ninfa/microbiologia , Óvulo/crescimento & desenvolvimento , Óvulo/microbiologia , Simbiose
11.
J Anal Methods Chem ; 2019: 1537568, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30719371

RESUMO

This work presents a reliable approach to trace teas' geographical origins despite changes in teas caused by different harvest years. A total of 1447 tea samples collected from various areas in 2014 (660 samples) and 2015 (787 samples) were detected by FT-NIR. Seven classifiers trained on the 2014 dataset all succeeded to trace origins of samples collected in 2014; however, they all failed to predict origins for the 2015 samples due to different data distributions and imbalanced dataset. Three outlier detection based undersampling approaches-one-class SVM (OC-SVM), isolation forest and elliptic envelope-were then proposed; as a result, the highest macro average recall (MAR) for the 2015 dataset was improved from 56.86% to 73.95% (by SVM). A model updating approach was also applied, and the prediction MAR was significantly improved with increase in the updating rate. The best MAR (90.31%) was first achieved by the OC-SVM combined SVM classifier at a 50% rate.

12.
Artigo em Inglês | MEDLINE | ID: mdl-29514522

RESUMO

Ladybird beetles (Coleoptera: Coccinellidae), with broad morphological diversity, wide geographic distribution and substantial agricultural significance, are a challenging group for taxonomists and phylogenetics. As a promising tool to identify and discover new species, DNA barcoding might offer significant potential for identification, taxonomy and phylogeny of ladybird beetles. In the present study, a total of 1364 COI (cytochrome C oxidase subunit I) sequences representing 128 species from 52 genera of ladybird beetles were screened for barcoding evaluation and phylogenetic analysis. Our results from the barcoding analysis revealed that COI displays a similar level of species identification efficiency (nearly 90%) either based on Kimura two-parameter (K2P) distances calculation or on simplified neighbour-joining (NJ) tree construction. The phylogenetic relationships within the family Coccinellidae was analyzed by Bayesian-inference (BI) method. The phylogenetic results confirmed the monophyly of the subfamilies Microweisinae and Coccinellinae sensu Slipinski (2007), and suggested that the subfamilies Coccidulinae, Chilocorinae and Scymninae are paraphyletic. However, the phylogenetic relationships among different subfamilies are not clearly defined and thus remain to be thoroughly studied. Overall, our study confirmed the usefulness of DNA barcoding for coccinellid species identification and phylogenetic inference.


Assuntos
Besouros/genética , Filogenia , Animais , Besouros/classificação , Código de Barras de DNA Taxonômico/métodos , Código de Barras de DNA Taxonômico/normas , Complexo IV da Cadeia de Transporte de Elétrons/genética , Proteínas de Insetos/genética
13.
Mitochondrial DNA B Resour ; 4(2): 3870-3871, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-33366227

RESUMO

The complete mitochondrial genome of an orb-weaver spider Araneus angulatus is 14,205 bp in length and contains 13 protein-coding genes, 2 ribosomal RNAs, 22 transfer RNAs, and a control region. The A + T content of the major strand is 75.4%. Nine of the protein-coding genes are initiated by typical ATN codons, one gene (COI) starts with TTA and other three genes (ND6, COII, and COIII) begin with TTG. The truncated stop codon (T) occurs in ND3, ND4L, and ND6, whereas the rest ten genes end with the canonical stop codon (TAA and TAG). Fifteen tRNAs lack the potential to form the typically cloverleaf-shaped secondary structure. The control region is 649 bp in length and contains a long tandem repeat region. The result of phylogenetic analysis shows that the relationship of A. angulatus was close to the species in the same family Araneidae.

14.
Genomics ; 111(6): 1266-1273, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-30145284

RESUMO

Mitochondrial genomes are widely used for phylogenetic and phylogeographic analyses among arthropods, but there is a lack of sufficient mitochondrial genome sequence data for spiders. Herein, we sequenced and characterized the complete mitochondrial genome of a crab spider Ebrechtella tricuspidata (Araneae: Thomisidae). The circular mitochondrial genome is 14,352 bp long, including a standard set of 37 genes and an A + T-rich region. Nucleotide composition is highly biased toward A + T nucleotides (77.3%). A novel gene order rearrangement is detected by a tRNA (trnL1) translocation. Tandem repeats are not identified in the A + T-rich region. Most of the tRNAs are greatly reduced in size and cannot be folded into typical cloverleaf-shaped secondary structures. The phylogenetic analysis confirms that the mitochondrial genome sequences are useful in resolving higher-level relationship of Araneae. Overall, our data present in this study will elevate our knowledge on the architecture and evolution of spider mitochondrial genome.


Assuntos
Genoma Mitocondrial , RNA de Transferência/genética , Aranhas/genética , Animais , Proteínas de Artrópodes/genética , Evolução Molecular , Filogenia , RNA Ribossômico/genética , Aranhas/classificação
15.
Mitochondrial DNA A DNA Mapp Seq Anal ; 29(5): 695-702, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-28712321

RESUMO

DNA barcoding has been widely used to identify and discover new species in a wide range of taxa. In order to assess the effectiveness of COI (cytochrome C oxidase subunit I) and 16S (16S ribosomal RNA) in the discrimination of spiders, we have generated 289 barcodes for a total of 56 farmland spider species from 14 different families for the first time in China. Our results reveal that the standard barcoding marker COI can be used to distinguish the farmland spiders both in species and family level by NJ tree-based method, despite the absence of a barcode gap between the intra- and inter-specific genetic divergences. 16S has a lower species identification success as compared with COI. However, almost 98% of the species can be correctly distinguished for both COI and 16S when a threshold of 3% nucleotide divergence was used for species discrimination. Our study significantly improves the barcode reference sequence library for Chinese farmland spiders, and will be very useful in pest management and eco-environmental monitoring and protection.


Assuntos
Complexo IV da Cadeia de Transporte de Elétrons/genética , Genoma de Inseto/genética , Aranhas/genética , Animais , China , DNA , Código de Barras de DNA Taxonômico/métodos , Fazendas , Especiação Genética , Variação Genética , Genoma Mitocondrial , Mitocôndrias/genética , Filogenia , RNA Ribossômico 16S/genética , Especificidade da Espécie
16.
Genetica ; 144(6): 699-709, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27822711

RESUMO

The complete mitogenome of the jumping spider Carrhotus xanthogramma was determined and comparative analysis among four salticid mitogenomes was conducted. The circular genome is 14,563 bp in size and contains a complete set of genes that usually present in the metazoa. All of the 13 protein-coding genes begin with a typical ATN codon and stop with the canonical stop codons, except for ND4 and ND4L genes with an incomplete stop codon T. All of the tRNAs cannot be formed the fully paired acceptor stems and seven out of them cannot be folded into the typical cloverleaf-shaped secondary structures. The tRNA Glu gene translocates its position as compared to the mitogenomes of other three determined jumping spiders. The A+T content of the majority strand and the A+T-rich region are 75.1 and 80%, respectively. The phylogenetic relationships based on concatenated nucleotide and amino acid sequences of 13 protein-coding genes using Maximum Likelihood and Bayesian Inference methods indicated that mitogenome sequences were useful in resolving higher-level relationship of Araneae.


Assuntos
Genoma Mitocondrial/genética , Genômica , Aranhas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Teorema de Bayes , Evolução Molecular , Ordem dos Genes , Proteínas de Insetos/química , Proteínas de Insetos/genética , Funções Verossimilhança , Filogenia , RNA Ribossômico/genética , RNA de Transferência/genética
17.
Molecules ; 21(10)2016 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-27681713

RESUMO

Phytochemical investigation of the twigs of Podocarpus nagi (Podocarpaceae) led to the isolation of two new abietane-type diterpenoids, named 1ß,16-dihydroxylambertic acid (1) and 3ß,16-dihydroxylambertic acid (2), along with two new ent-pimarane-type diterpenoids, named ent-2ß,15,16,18-tetrahydroxypimar-8(14)-ene (3) and ent-15-oxo-2ß,16,18-trihydroxypimar-8(14)-ene (4). Their respective structures were elucidated on the basis of spectroscopic analyses, including 1D- and 2D-NMR, IR, CD, and HR-ESI-MS. This is the first time ent-pimarane-type diterpenoids from the genus Podocarpus has been reported. All four new compounds were tested for cytotoxic activity. The MTT assay results showed that compounds 3 and 4 significantly inhibited the proliferation of human cervical cancer Hela cells, human lung cancer A549 cells, and human breast cancer MCF-7 cells at a concentration of 10 µM. Furthermore, using the lipopolysaccharide (LPS)-stimulated RAW264.7 cells, compounds 2 and 4 were found to significantly inhibit nitrogen oxide (NO) production with IC50 values of 26.5 ± 6.1 and 17.1 ± 1.5 µM, respectively.

18.
Gene ; 590(2): 298-306, 2016 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-27259661

RESUMO

The complete mitogenomes of two orb-weaving spiders Neoscona doenitzi and Neoscona nautica were determined and a comparative mitogenomic analysis was performed to depict evolutionary trends of spider mitogenomes. The circular mitogenomes are 14,161bp with A+T content of 74.6% in N. doenitzi and 14,049bp with A+T content of 78.8% in N. nautica, respectively. Both mitogenomes contain a standard set of 37 genes typically presented in metazoans. Gene content and orientation are identical to all previously sequenced spider mitogenomes, while gene order is rearranged by tRNAs translocation when compared with the putative ancestral gene arrangement pattern presented by Limulus polyphemus. A comparative mitogenomic analysis reveals that the nucleotide composition bias is obviously divergent between spiders in suborder Opisthothelae and Mesothelae. The loss of D-arm in the trnS(UCN) among all of Opisthothelae spiders highly suggested that this common feature is a synapomorphy for entire suborder Opisthothelae. Moreover, the trnS(AGN) in araneoids preferred to use TCT as an anticodon rather than the typical anticodon GCT. Phylogenetic analysis based on the 13 protein-coding gene sequences consistently yields trees that nest the two Neoscona spiders within Araneidae and recover superfamily Araneoidea as a monophyletic group. The molecular information acquired from the results of this study should be very useful for future research on mitogenomic evolution and genetic diversities in spiders.


Assuntos
Genoma Mitocondrial , Filogenia , Aranhas/genética , Animais , Composição de Bases/genética , Sequência de Bases , Códon/genética , Genes Mitocondriais , Conformação de Ácido Nucleico , Nucleotídeos/genética , Fases de Leitura Aberta/genética , RNA Ribossômico/genética , RNA de Transferência/genética
19.
Int J Biol Sci ; 12(1): 109-19, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26722222

RESUMO

Mitogenomes can provide information for phylogenetic analysis and evolutionary biology. The Araneae is one of the largest orders of Arachnida with great economic importance. In order to develop mitogenome data for this significant group, we determined the complete mitogenomes of two long jawed spiders Tetragnatha maxillosa and T. nitens and performed the comparative analysis with previously published spider mitogenomes. The circular mitogenomes are 14578 bp long with A+T content of 74.5% in T. maxillosa and 14639 bp long with A+T content of 74.3% in T. nitens, respectively. Both the mitogenomes contain a standard set of 37 genes and an A+T-rich region with the same gene orientation as the other spider mitogenomes, with the exception of the different gene order by the rearrangement of two tRNAs (trnW and trnG). Most of the tRNAs lose TΨC arm stems and have unpaired amino acid acceptor arms. As interesting features, both trnS(AGN) and trnS(UCN) lack the dihydrouracil (DHU) arm and long tandem repeat units are presented in the A+T-rich region of both the spider mitogenomes. The phylogenetic relationships of 23 spider mitogenomes based on the concatenated nucleotides sequences of 13 protein-coding genes indicated that the mitogenome sequences could be useful in resolving higher-level relationship of Araneae. The molecular information acquired from the results of this study should be very useful for future researches on mitogenomic evolution and genetic diversities in spiders.


Assuntos
Genoma Mitocondrial/genética , RNA de Transferência/genética , Aranhas/genética , Animais , Genoma de Inseto/genética , Filogenia
20.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(6): 3909-3910, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-25484171

RESUMO

The complete mitochondrial genome of the wolf spider Wadicosa fidelis was determined. It is a circular molecule of 14,741 bp in length and contains a standard set of 13 protein-coding genes, 2 ribosomal RNAs, 22 transfer RNAs and a control region. The A + T content of the overall base composition of majority strand (J-strand) is 76.1% (T: 43.0%; C: 8.2%; A:33.1%; G: 15.7%). Start codons in all 13 protein-coding genes (PCGs) follow the ATN rule, except of four genes (COII, COII, ND4 and ND6), which have TTG start codon. The usual termination codons (TAA and TAG) are found from nine PCGs. However, COI, ND1, ND4L, ND5 had an incomplete termination codon (T). The control region (D-loop) is 1071 bp long with 67.9% A + T content, and contains a long tandem repeat region, which is comprising three full 215 bp copies and a partial fourth (87 bp) copy.


Assuntos
Genoma Mitocondrial , Aranhas/genética , Animais , Proteínas de Artrópodes/genética , Composição de Bases , Códon de Iniciação , Códon de Terminação , DNA Mitocondrial/química , DNA Mitocondrial/isolamento & purificação , DNA Mitocondrial/metabolismo , Fases de Leitura Aberta/genética , RNA Ribossômico/química , RNA Ribossômico/genética , RNA de Transferência/química , RNA de Transferência/genética , Análise de Sequência de DNA
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