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1.
Med Vet Entomol ; 38(1): 59-72, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37771128

RESUMO

Pederin, a defensive toxin in Paederus fuscipes, is produced by an uncultured Gram-negative symbiont, which establishes a stable symbiotic relationship with a female host before completion of metamorphosis. However, the transmission process of pederin-producing bacteria (PPB) in P. fuscipes at different life stages remains unknown. Herein, the PPB population dynamics and transcriptome atlas for P. fuscipes development (egg, first-instar larva, second-instar larva, pupa, and newly emerged female and male) were characterised. We found that a microbial layer containing PPB covered the eggshell, which could be sterilised by smearing the eggshell with streptomycin. Maternal secretions over the eggshell are likely the main PPB acquisition route for P. fuscipes offspring. The PPB density in eggs was significantly higher than that in other life stages (p < 0.05), which demonstrated that the beetle mothers gave more PPB than the larvae acquired. Physiological changes (hatching and eclosion) led to a decreased PPB density in P. fuscipes. Pattern recognition receptors related to Gram-negative bacteria recognition were identified from P. fuscipes transcriptomes across various life stages, which might be used to screen genes involved in PPB regulation. These results will help advance future efforts to determine the molecular mechanisms of PPB colonisation of P. fuscipes.


Assuntos
Besouros , Masculino , Feminino , Animais , Besouros/microbiologia , Besouros/fisiologia , Bactérias/genética , Larva , Piranos
2.
Phys Chem Chem Phys ; 25(7): 5776-5784, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36744468

RESUMO

State-of-the-art first-principles calculations are performed to investigate the thermoelectric transport properties in thallium-based fluoride perovskites TlXF3 (X = Hg, Sn, Pb) by considering anharmonic renormalization of the phonon energy and capturing reasonable electron relaxation times. The lattice thermal conductivity, κL, of the three compounds is very low, among which TlPbF3 is only 0.42 W m-1 K-1 at 300 K, which is less than half of that of quartz glass. The low acoustic mode group velocity and strong three-phonon scattering caused by the strong anharmonicity of the Tl atom are the origin of the ultralow κL. Meanwhile, the strong ionic bonds between X (X = Hg, Sn, Pb) and F atoms provide good electrical transport properties. The results show that the ZT value of TlHgF3 at 900 K is 1.58, which is higher than the 1.5 value of FeNbSb at 1200 K. TlSnF3 and TlPbF3 also exceed 1, which is close to the classical thermoelectric material PbTe:Na. Furthermore, we present the methods and expected effects of improving the ZT value through nanostructures.

3.
J Chem Phys ; 158(1): 014107, 2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36610964

RESUMO

The thermoelectric properties of RbBaX (X = Sb, Bi), an anisotropic material with strong anharmonicity, are systematically studied by first-principles calculations, combined with the self-consistent phonon theory and the Boltzmann transport equation. A reasonable lattice thermal conductivity κL is captured by fully handling the phonon frequency shift and four-phonon scattering caused by the quartic anharmonicity. The κL of RbBaSb and RbBaBi along the a-axis is only 0.60 and 0.36 W m-1 K-1 at 300 K, respectively, which is much lower than that of most thermoelectric materials. The low phonon group velocity resulting from the unusually weak atomic bonding strengths along the a-axis is the origin of the ultralow κL. Furthermore, the high dispersion near the conduction band minimum enables n-type doping with a higher electrical conductivity. The results show that orthorhombic RbbaBi has a ZT as high as 1.04 at 700 K along the a-axis direction, indicating its great application potential in the thermoelectric field.

4.
Insect Mol Biol ; 31(4): 457-470, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35302262

RESUMO

Pederin, a group of antitumor compounds, is produced by an endosymbiotic bacterium of Paederus fuscipes. Pederin content differed between male and female P. fuscipes, but the reason why these differences are maintained remains unexplored. Here, the pederin-producing bacteria (PPB) infection rate in P. fuscipes was investigated. Furthermore, we assessed the microbiota structure differences in male and female P. fuscipes harbouring PPB and sequenced the transcriptome of both sexes to shed light on genes of interest. Of the 625 analysed beetles (275 females, 350 males), 96.36% of females and 31.14% of males were positive for PPB infection. PPB accounted for 54.36%-82.70% of the bacterial population in females but showed a much lower abundance in males (0.92%-3.87%). Reproductive organs possessed the highest PPB abundance compared with other parts of females, but no such relationships existed in males. Moreover, we provide the first transcriptome analysis of male and female P. fuscipes harbouring PPB and identified 8893 differentially expressed unigenes. Our results indicated that the pederin content difference between males and females might be caused by the PPB density difference in hosts. The biosequence data would be helpful for illustrating the mechanism that regulates PPB density in P. fuscipes.


Assuntos
Besouros , Microbiota , Animais , Bactérias/genética , Besouros/genética , Feminino , Masculino , Piranos , Transcriptoma
5.
J Magn Reson Imaging ; 50(2): 397-409, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30589158

RESUMO

BACKGROUND: Accurate estimation of the recurrence of pancreatic neuroendocrine tumors help with prognosis, guide follow-up, and avoid futile treatments. PURPOSE: To investigate whether MRI features could preoperatively estimate the recurrence of pancreatic neuroendocrine tumors (PNETs) and to refine a novel prognostic model through developing a nomogram incorporating various MRI features. STUDY TYPE: Retrospective. POPULATION: In all, 81 patients with clinicopathologically confirmed nonmetastatic PNETs. FIELD STRENGTH/SEQUENCES: 1.5 T MR, including T1 -weighted, T2 -weighted, and diffusion-weighted imaging sequences. ASSESSMENT: Qualitative and quantitative MRI features of PNET were assessed by three experienced radiologists. STATISTICAL TESTS: Uni- and multivariable analyses for recurrence-free survival (RFS) were evaluated using a Cox proportional hazards model. The MRI-based nomogram was then designed based on multivariable logistic analysis in our study and the performance of the nomogram was validated according to C-index, calibration, and decision curve analyses. RESULTS: MRI features, including tumor size (hazard ratio [HR]: 14.131; P = 0.034), enhancement pattern (HR: 21.821, P = 0.032), and the apparent diffusion coefficient (ADC) values (HR: 0.055, P = 0.038) were significant independent predictors of RFS at multivariable analysis. The performance of the nomogram incorporating various MRI features (with a C-index of 0.910) was improved compared with that based on tumor size, enhancement pattern, and ADC alone (with C-index values of 0.672, 0.851, and 0.809, respectively). The calibration curve of the nomogram exhibited perfect consistency between estimation and observation at 0.5, 1, and 2 years after surgery. The decision curve showed that a nomogram incorporating three features had more favorable clinical predictive usefulness than any single feature. DATA CONCLUSION: MRI features can be considered effective recurrence predictors for PNETs after surgery. The preliminary nomogram incorporating various MRI features could assess the risk of recurrence in PNETs and may be used to optimize individual treatment strategies. LEVEL OF EVIDENCE: 4 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;50:397-409.


Assuntos
Imageamento por Ressonância Magnética , Tumores Neuroendócrinos/diagnóstico por imagem , Nomogramas , Neoplasias Pancreáticas/diagnóstico por imagem , Adulto , Idoso , Algoritmos , Calibragem , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Tumores Neuroendócrinos/cirurgia , Neoplasias Pancreáticas/cirurgia , Prognóstico , Reprodutibilidade dos Testes , Estudos Retrospectivos , Risco , Adulto Jovem
6.
J Nanobiotechnology ; 16(1): 8, 2018 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-29378591

RESUMO

BACKGROUND: Trueperella pyogenes is a commensal and opportunistic pathogen that normally causes mastitis, liver abscesses and pneumonia of economically important livestock. To develop efficacious and potent vaccine against T. pyogenes, chimeric gene DNA vaccines were constructed and encapsulated in chitosan nanoparticles (pPCFN-CpG-CS-NPs). RESULTS: The pPCFN-CpG-CS-NPs consists of the plo, cbpA, fimA, and nanH gene of T. pyogenes and CpG ODN1826. It was produced with good morphology, high stability, a mean diameter of 93.58 nm, and a zeta potential of + 5.27 mV. Additionally, chitosan encapsulation was confirmed to protect the DNA plasmid from DNase I digestion. The immunofluorescence assay indicated that the four-chimeric gene could synchronously express in HEK293T cells and maintain good bioactivity. Compared to the mice immunized with the control plasmid, in vivo immunization showed that mice immunized with the pPCFN-CpG-CS-NPs had better immune responses, and release of the plasmid DNA was prolonged. Importantly, immunization with pPCFN-CpG-CS-NPs could significantly protect mice from highly virulent T. pyogenes TP7 infection. CONCLUSIONS: This study indicates that chitosan-DNA nanoparticles are potent immunization candidates against T. pyogenes infection and provides strategies for the further development of novel vaccines encapsulated in chitosan nanoparticles.


Assuntos
Actinobacteria/imunologia , Quitosana/química , DNA/química , Imunogenicidade da Vacina , Nanopartículas/química , Vacinação , Vacinas de DNA/imunologia , Sequência de Aminoácidos , Animais , Formação de Anticorpos/imunologia , Proliferação de Células , Contagem de Colônia Microbiana , Citocinas/metabolismo , Epitopos/química , Feminino , Células HEK293 , Humanos , Imunidade Humoral/imunologia , Injeções Intraperitoneais , Camundongos , Nanopartículas/ultraestrutura , Oligodesoxirribonucleotídeos/imunologia , Plasmídeos/metabolismo , Linfócitos T/citologia , Linfócitos T/imunologia
7.
Arch Microbiol ; 199(5): 649-655, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28144921

RESUMO

Trueperella pyogenes is a prevalent opportunistic bacterium that normally causes diverse suppurative lesions, endometritis and pneumonia in various economically important animals. Although the genomic information of this species has been announced, little is known about its functional profiles. In this study, by performing a comparative transcriptome analysis between the highly and moderately virulent T. pyogenes isolates, we found the expression of a LuxR-type DNA-binding response regulator, PloR, was significantly up-regulated in the highly virulent T. pyogenes. Protein crystal structure prediction and primary functional assessment suggested that, the quorum-sensing signal molecules of Gram-negative bacteria such as Pseudomonas aeruginosa and Escherichia coli could significantly inhibit the growth, biofilm production and hemolysis of T. pyogenes by binding to the upstream sensor histidine kinase, PloS. Therefore, the PloS/PlosR two-component regulatory system might dominate the virulence of T. pyogenes. Our findings provide a major advance in understanding the pathogenesis of T. pyogenes, and may shed new light on the development of novel therapeutic strategies to control T. pyogenes infection.


Assuntos
Actinomycetaceae/genética , Actinomycetaceae/patogenicidade , Infecções por Actinomycetales/patologia , Proteínas de Ligação a DNA/biossíntese , Perfilação da Expressão Gênica , Histidina Quinase/metabolismo , Actinomycetaceae/crescimento & desenvolvimento , Infecções por Actinomycetales/microbiologia , Animais , Anti-Infecciosos , Biofilmes/crescimento & desenvolvimento , Escherichia coli/metabolismo , Feminino , Histidina Quinase/genética , Pseudomonas aeruginosa/metabolismo , Percepção de Quorum , Virulência/genética , Fatores de Virulência/genética
8.
J Hered ; 107(5): 423-30, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27112165

RESUMO

Recently, an increasing number of microsatellites or simple sequence repeats (SSRs) have been found and characterized from transcriptomes. Such SSRs can be employed as putative functional markers to easily tag corresponding genes, which play an important role in biomedical studies and genetic analysis. However, the transcriptome-derived SSRs for giant panda (Ailuropoda melanoleuca) are not yet available. In this work, we identified and characterized 20 tetranucleotide microsatellite loci from a transcript database generated from the blood of giant panda. Furthermore, we assigned their predicted transcriptome locations: 16 loci were assigned to untranslated regions (UTRs) and 4 loci were assigned to coding regions (CDSs). Gene identities of 14 transcripts contained corresponding microsatellites were determined, which provide useful information to study the potential contribution of SSRs to gene regulation in giant panda. The polymorphic information content (PIC) values ranged from 0.293 to 0.789 with an average of 0.603 for the 16 UTRs-derived SSRs. Interestingly, 4 CDS-derived microsatellites developed in our study were also polymorphic, and the instability of these 4 CDS-derived SSRs was further validated by re-genotyping and sequencing. The genes containing these 4 CDS-derived SSRs were embedded with various types of repeat motifs. The interaction of all the length-changing SSRs might provide a way against coding region frameshift caused by microsatellite instability. We hope these newly gene-associated biomarkers will pave the way for genetic and biomedical studies for giant panda in the future. In sum, this set of transcriptome-derived markers complements the genetic resources available for giant panda.


Assuntos
Repetições de Microssatélites , Transcriptoma , Ursidae/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Bases de Dados de Ácidos Nucleicos , Marcadores Genéticos , Fases de Leitura Aberta , Locos de Características Quantitativas , Transcrição Gênica , Regiões não Traduzidas
9.
Diagnostics (Basel) ; 13(7)2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-37046555

RESUMO

Steatohepatitic hepatocellular carcinoma (SH-HCC) is a distinctive histologic variant of HCC for the presence of steatohepatitis. This study intended to evaluate the contrast-enhanced imaging features and clinicopathological characteristics of 26 SH-HCCs in comparison with 26 age-and-sex-matched non-SH-HCCs. The frequency of obesity (34.6%, p = 0.048) and type 2 diabetes mellitus (23.1%, p = 0.042) were significantly higher in SH-HCC patients. As seen via B-mode ultrasound (BMUS), SH-HCCs were predominantly hyperechoic (65.4%, p = 0.002) lesions, while non-SH-HCCs were mainly hypo-echoic. As seen via contrast-enhanced ultrasound (CEUS), 96.2% of SH-HCCs exhibited hyperenhancement in the arterial phase. During the portal venous and late phase, 88.5% of SH-HCCs showed late and mild washout. Consequently, most SH-HCCs and all non-SH-HCCs were categorized as LR-4 or LR-5. As seen via magnetic resonance imaging (MRI), a signal drop in the T1WI opposed-phase was observed in 84.6% of SH-HCCs (p = 0.000). Notably, diffuse fat in mass was detected in 57.7% (15/26) SH-HCCs (p < 0.001). As seen via contrast-enhanced MRI (CEMRI), most of the SH-HCCs and non-SH-HCCs exhibited heterogeneous hyperenhancement in the arterial phase (80.8% versus 69.2%, p = 0.337). During the delayed phase, 76.9% SH-HCCs and 88.5% non-SH-HCCs exhibited hypo-enhancement. Histopathologically, the rate of microvascular invasion (MVI) was significantly lower in SH-HCCs than non-SH-HCCs (42.3% versus 73.1%, p = 0.025). The frequency of hepatic steatosis >5% in non-tumoral liver parenchyma of SH-HCCs was significantly higher than in non-SH-HCCs (88.5% versus 26.9%, p = 0.000). Additionally, the fibrotic stages of S0, S1 and S2 in SH-HCCs were significantly higher than in non-SH-HCCs (p = 0.044). During follow-up, although the PFS of SH-HCC patients was significantly longer than non-SH-HCC patients (p = 0.046), for the overall survival rate of SH-HCC and non-SH-HCC patients there was no significant difference (p = 0.162). In conclusion, the frequency of metabolism-related diseases in SH-HCC patients was significantly higher than in non-SH-HCC patients. The imaging features of SH-HCCs combined the fatty change and typical enhancement performance of standard HCC as seen via CEUS/CEMRI.

10.
Ecol Evol ; 12(7): e9060, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35813924

RESUMO

Predatory natural enemies play key functional roles in biological control. Abundant predatory arthropod species have been recorded in tea plantation ecosystems. However, few studies have comprehensively evaluated the control effect of predatory arthropods on tea pests in the field. We performed a 1-year field investigation and collected predatory arthropods and pests in the tea canopy. A total of 7931 predatory arthropod individuals were collected, and Coleosoma blandum (Araneae, Theridiidae) was the most abundant species in the studied tea plantation. The population dynamics between C. blandum and four main tea pest species (Aleurocanthus spiniferus, Empoasca onukii, Ectropis grisescens, and Scopula subpunctaria) were established using the individual number of predators and pests in each month. The results showed that C. blandum appeared to co-occur in the tea canopy with A. spiniferus, Em. onukii, and Ec. grisescens in a longer period. The prey spectrum of C. blandum was further analyzed using DNA metabarcoding. Among prey species, A. spiniferus, Em. onukii, and Ec. grisescens were included, and the relative abundance and positive rates of target DNA fragments of A. spiniferus were greater than that of other two pests. Combined with the high dominance index of C. blandum, co-occurrence between C. blandum and A. spiniferus in time and space and high positive rate and relative abundance of target DNA fragments of A. spiniferus, C. blandum was identified to prey on A. spiniferus, and C. blandum may be an important predator of A. spiniferus. Thus, C. blandum has potential as a biological control agent of A. spiniferus in an integrated pest management strategy.

11.
Vaccines (Basel) ; 10(6)2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35746448

RESUMO

Trueperella pyogenes (T. pyogenes) is a crucial opportunistic pathogen normally causing mastitis, abscesses and pneumonia in economically important ruminants. Although only one commercial vaccine of T. pyogenes is currently obtainable, its immunoprotective effect is limited. Pyolysin (PLO) is the most predominant virulence factor highly expressed in T. pyogenes and is an excellent target for the development of novel vaccines against T. pyogenes. In this study, we designed a heterologous prime-boost vaccination scheme combining a DNA vaccine pVAX1-PLO and a subunit vaccine His-PLO to maximize host responses in mice. Humoral and cellular immune responses and protective effects were evaluated in mice to compare the immunogenicity induced by different immunization schemes. Compared to the PBS-control group, in vivo immunization results showed that better immune responses of mice immunized with the pVAX1-PLO plasmids and His-PLO proteins were induced. The residual bacterial burdens from the liver and peritoneal fluid were remarkably decreased in the immunized mice compared with the PBS group. Notably, the heterologous prime-boost vaccination groups significantly enhanced host humoral and cellular immune responses and protected mice from different virulent T. pyogenes strains infection. Conclusively, this study provides a favorable strategy for the further development of next-generation vaccines against T. pyogenes infections.

12.
Ecol Evol ; 11(21): 15444-15454, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34765189

RESUMO

As one of the most abundant predators of insects in terrestrial ecosystems, spiders have long received much attention from agricultural scientists and ecologists. Do spiders have a certain controlling effect on the main insect pests of concern in farmland ecosystems? Answering this question requires us to fully understand the prey spectrum of spiders. Next-generation sequencing (NGS) has been successfully employed to analyze spider prey spectra. However, the high sequencing costs make it difficult to analyze the prey spectrum of various spider species with large samples in a given farmland ecosystem. We performed a comparative analysis of the prey spectra of Ovia alboannulata (Araneae, Lycosidae) using NGS with individual and mixed DNA samples to demonstrate which treatment was better for determining the spider prey spectra in the field. We collected spider individuals from tea plantations, and two treatments were then carried out: (1) The DNA was extracted from the spiders individually and then sequenced separately (DESISS) and (2) the DNA was extracted from the spiders individually and then mixed and sequenced (DESIMS). The results showed that the number of prey families obtained by the DESISS treatment was approximately twice that obtained by the DESIMS treatment. Therefore, the DESIMS treatment greatly underestimated the prey composition of the spiders, although its sequencing costs were obviously lower. However, the relative abundance of prey sequences detected in the two treatments was slightly different only at the family level. Therefore, we concluded that if our purpose were to obtain the most accurate prey spectrum of the spiders, the DESISS treatment would be the best choice. However, if our purpose were to obtain only the relative abundance of prey sequences of the spiders, the DESIMS treatment would also be an option. The present study provides an important reference for choosing applicable methods to analyze the prey spectra and food web compositions of animal in ecosystems.

13.
Mitochondrial DNA B Resour ; 6(7): 1953-1955, 2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34179478

RESUMO

Ectropis grisescens (Lepidoptera, Geometridae) is one of the main leaf-eating pests in tea plantations in China. In this study, the complete mitochondrial genome of this species was sequenced and assembled. The total length of the mitochondrial genome of E. grisescens was 15,794 bp (GenBank accession No. MW337302). The base composition was 41.26% for A, 39.49% for T, 7.92% for G, and 11.33% for C. The circular mitogenome contained 13 protein-coding genes, 2 ribosomal RNA genes, and 22 transfer RNA genes. Phylogenetic analysis performed using 13 protein-coding genes of 15 species of Geometridae and an out-group Pieris melete (Lepidoptera, Pieridae) showed that E. grisescens is closely related to species of E. obliqua, and this is consistent with the morphological identification.

14.
Front Genet ; 12: 622724, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33719337

RESUMO

Microsatellite or simple sequence repeat (SSR) instability within genes can induce genetic variation. The SSR signatures remain largely unknown in different clades within Euarchontoglires, one of the most successful mammalian radiations. Here, we conducted a genome-wide characterization of microsatellite distribution patterns at different taxonomic levels in 153 Euarchontoglires genomes. Our results showed that the abundance and density of the SSRs were significantly positively correlated with primate genome size, but no significant relationship with the genome size of rodents was found. Furthermore, a higher level of complexity for perfect SSR (P-SSR) attributes was observed in rodents than in primates. The most frequent type of P-SSR was the mononucleotide P-SSR in the genomes of primates, tree shrews, and colugos, while mononucleotide or dinucleotide motif types were dominant in the genomes of rodents and lagomorphs. Furthermore, (A)n was the most abundant motif in primate genomes, but (A)n, (AC)n, or (AG)n was the most abundant motif in rodent genomes which even varied within the same genus. The GC content and the repeat copy numbers of P-SSRs varied in different species when compared at different taxonomic levels, reflecting underlying differences in SSR mutation processes. Notably, the CDSs containing P-SSRs were categorized by functions and pathways using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes annotations, highlighting their roles in transcription regulation. Generally, this work will aid future studies of the functional roles of the taxonomic features of microsatellites during the evolution of mammals in Euarchontoglires.

15.
Biodivers Data J ; 8: e60143, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33335446

RESUMO

BACKGROUND: Spiders are the most dominant predatory natural enemies of insect pests in the tea plantation ecosystem. There has been a large amount of literature published about the investigation of spider species in Chinese tea plantations from 1982 to 2020. Here, the spider species in Chinese tea plantations has been summarised and the dominant spider species in each regional tea plantation recorded. To date, there were 535 spider species from 40 families reported in Chinese tea plantations. NEW INFORMATION: There are 245 spider species from 13 families now being added to the checklist. A total of 89 spider species from 19 families were the dominant species, amongst them, Agelena labyrinthica, Allagelena difficilis, Neoscona theisi, Clubiona deletrix, Clubiona japonicola, Hylyphantes graminicola, Pardosa laura, Oxyopes sertatus, Evarcha albaria, Plexippus paykulli, Coleosoma octomaculatum, Ebrechtella tricuspidata and Xysticus ephippiatus were recorded in many tea plantations. The checklist will provide important data for the biodiversity and distribution of spiders in tea plantations of China.

16.
Gene ; 757: 144919, 2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-32603771

RESUMO

Simple sequence repeats (SSRs) represent an important source of genetic variation that provides a basis for adaptation to different environments in organisms. In this study, we examined the distribution patterns of SSRs in twenty-nine beetle genomes and carried out Gene Ontology (GO) analysis of CDSs embedded with perfect SSRs (P-SSRs). The results demonstrated that imperfect SSRs (I-SSRs) represented the most abundant SSR category in beetle genomes and in different genomic regions (CDS, exon, and intron regions). The numbers of P-SSRs, I-SSRs, compound SSRs, and variable number tandem repeats were positively correlated with beetle genome size, whereas neither the frequency nor the density of the SSRs was correlated with genome size. Moreover, our results demonstrated that common genomic features of P-SSRs within the same suborder or family of Coleoptera were rare. Mono-, di-, tri-, or tetranucleotide SSRs were the most abundant P-SSR categories in beetle genomes. The preferred predominant repeat motif among the mononucleotide P-SSRs was (A)n, but the most frequent repeat motifs for other length classes varied differentially among these genomes. Furthermore, the P-SSR type with the highest GC content differed in the beetle genomes and in different genomic regions. CV (coefficient of variability) analysis demonstrated that the repeat copy numbers of P-SSRs presented relatively higher variation in introns than in CDSs and exons. The GO terms of CDSs containing P-SSRs for molecular functions were mainly enriched in "binding" and "transcription". Our findings will be useful for studying the functional roles of microsatellite heterogeneity in beetle adaptation.


Assuntos
Besouros/genética , Genoma de Inseto , Repetições de Microssatélites , Polimorfismo Genético , Animais , Composição de Bases
17.
Vet Microbiol ; 235: 199-208, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31383303

RESUMO

Trueperella pyogenes is an importantly opportunistic and commensal pathogen that causes suppurative lesions of most economically important livestock. To understand the molecular mechanism underlying the infection by T. pyogenes, we carried out a large-scale transcriptome sequencing of mice livers intraperitoneally infected with T. pyogenes using RNA-sequencing. A total of 47 G clean bases were obtained and 136 differentially expressed genes were detected between the control and the infection groups in the liver transcriptomes. Additionally, we found that the expression of a key autophagy regulator, mTOR (mechanistic target of rapamycin) was significantly up-regulated in the infection groups. Mechanistically, T. pyogenes infection induced the expression of mTOR and subsequently inhibited the autophagy of host cell. Blocking autophagy with inhibitor 3-methyladenine (3-MA) or silencing autophagy-related gene 7 (Atg7) reduced the effect of bacterial elimination. Interestingly, inhibition of mTOR induced autophagy and reduced T. pyogenes viability in RAW264.7 murine macrophages. The silencing mTOR regulated oxidation and cytokines (interleukin-1ß, IL-6 and tumor necrosis factro-α) against T. pyogenes in macrophages and significantly protected mice from T. pyogenes challenge. These findings indicate that mTOR is a novel functional regulator in autophagy-mediated T. pyogenes elimination and will be useful to further knowledge on the development of effective therapeutic strategy to control T. pyogenes-related diseases.


Assuntos
Autofagia , Infecções por Bactérias Gram-Positivas/imunologia , Serina-Treonina Quinases TOR/imunologia , Actinomycetaceae , Adenina/análogos & derivados , Adenina/farmacologia , Animais , Proteína 7 Relacionada à Autofagia/genética , Citocinas/imunologia , Modelos Animais de Doenças , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Inativação Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Fígado/microbiologia , Macrófagos/imunologia , Camundongos
18.
Vet Microbiol ; 213: 89-94, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29292009

RESUMO

Trueperella pyogenes is a gram-positive opportunistic pathogen normally causes mastitis, liver abscesses and pneumonia of economically important livestock. It has been suggested that gram-negative bacteria can suppress the growth and virulence of T. pyogenes in vitro by using the quorum-sensing (QS) signal molecules and cause the transition of predominant species. However, whether these QS signals can be used as potential anti-virulence drugs against T. pyogenes infection is unclear. In this study, the in vivo inhibitory effect N-acyl homoserine lactones (AHLs) from Escherichia coli and Pseudomonas aeruginosa on T. pyogenes was tested by using mouse model. Mice were first peritoneally infected with T. pyogenes followed by intravenous injection of N-Octanoyl-DL-homoserine lactone (C8HSL) or N-(3-oxododecanoyl) homoserine-l-lactone (C12HSL). The results showed that C8HSL and C12HSL significantly reduced bacterial load and increased the survival rate of mice against T. pyogenes challenge. Additionally, the treatment of AHLs promoted the secretion of IL-1ß, IL-6, IL-8 and TNF-α in mouse peritoneal fluid, and significantly decreased the expression levels of virulence genes of residual T. pyogenes. Importantly, murine macrophages rapidly phagocytosed bacteria when they were treated with AHLs compared to untreated cells. Collectively, our findings provide a major advance in understanding the inhibitory effect of AHLs in vivo and a promise for developing new clinical or veterinary treatments of T. pyogenes-related infection.


Assuntos
Actinomycetaceae/fisiologia , Infecções por Actinomycetales/prevenção & controle , Acil-Butirolactonas/farmacologia , Percepção de Quorum/efeitos dos fármacos , Actinomycetaceae/efeitos dos fármacos , Actinomycetaceae/patogenicidade , Infecções por Actinomycetales/microbiologia , Animais , Modelos Animais de Doenças , Feminino , Macrófagos , Camundongos , Fagocitose , Organismos Livres de Patógenos Específicos , Virulência , Fatores de Virulência
19.
Gene ; 578(2): 274-80, 2016 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-26707213

RESUMO

The blister beetle is an important resource insect due to its defensive substance cantharidin, which was widely used in pharmacology and plant protection. We determined the complete mitochondrial genome of Epicauta chinensis Laporte (Coleoptera: Tenebrionoidae: Meloidae). The circular genome is 15,717 bp long, encoding 13 protein-coding genes (PCGs), two ribosomal RNAs and 22 tRNAs and containing a A+T-rich region with gene arrangement identical to other Coleopteran species. Twelve PCGs start with typical ATN codon, while ATP8 gene initiate with GTT for first report in Insecta. All PCGs terminate with conventional stop codon TAA or TAG. All tRNAs in E. chinensis are predicted to fold into typical cloverleaf secondary structure, except tRNA-Ser(AGN), in which the dihydrouracil arm (DHU arm) could not form stable stem-loop structure. The secondary structure of lrRNA and srRNA comprises 48 helices and 32 helices respectively. The 1101 bp A+T-rich region contains a 15 bp poly-T stretch and microsatellite-like repeats rather than large tandem repetitive sequences. Phylogenetic analysis, based on 13 PCGs of 45 Coleopteran species, show that E. chinensis grouped with Tenebrionidae species. It also support the topology of (((Chrysomelidae+Curculionoidea)+(Cucujoidea+Cleroidea))+Tenebrionoidea) within Cucujiformia.


Assuntos
Besouros/genética , Genoma Mitocondrial/genética , Filogenia , Animais , Códon , Ordem dos Genes , Conformação de Ácido Nucleico , RNA Ribossômico/genética , RNA de Transferência/genética
20.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(3): 1882-4, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-25329279

RESUMO

The complete mitochondrial genome of L. edwardsi was first sequenced and characterized. The genome was 16,284 bases in length and the composition and arrangement of its genes are analogous to most other rodents. The nucleotide sequence date of 12 heavy-strand protein-coding genes of L. edwardsi and other 26 Muridae species were used for phylogenetic analyses. Trees constructed using Maximum Likelihood, Neighbor Joining and Minimum Evolution demonstrated that L. edwardsi was closer to the genus Niviventer than Rattus. Combing previous research, it suggests that Edward's long-tailed rat is more suitable to be classified into genus Leopoldamys and named as Leopoldamys edwardsi. This study suggested that R. edwardsi is inappropriate for the other name of L. edwardsi.


Assuntos
Genoma Mitocondrial , Muridae/genética , Animais , Pareamento de Bases/genética , Sequência de Bases , DNA Mitocondrial/genética , Ordem dos Genes , Genes Mitocondriais , Filogenia , RNA de Transferência/genética
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