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1.
Entropy (Basel) ; 26(7)2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-39056941

RESUMO

The rapid evolution of computer technology and social networks has led to massive data generation through interpersonal communications, necessitating improved methods for information mining and relational analysis in areas such as criminal activity. This paper introduces a Social Network Forensic Analysis model that employs network representation learning to identify and analyze key figures within criminal networks, including leadership structures. The model incorporates traditional web forensics and community algorithms, utilizing concepts such as centrality and similarity measures and integrating the Deepwalk, Line, and Node2vec algorithms to map criminal networks into vector spaces. This maintains node features and structural information that are crucial for the relational analysis. The model refines node relationships through modified random walk sampling, using BFS and DFS, and employs a Continuous Bag-of-Words with Hierarchical Softmax for node vectorization, optimizing the value distribution via the Huffman tree. Hierarchical clustering and distance measures (cosine and Euclidean) were used to identify the key nodes and establish a hierarchy of influence. The findings demonstrate the effectiveness of the model in accurately vectorizing nodes, enhancing inter-node relationship precision, and optimizing clustering, thereby advancing the tools for combating complex criminal networks.

2.
Theor Appl Genet ; 136(1): 3, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36651948

RESUMO

KEY MESSAGE: The QYm.nau-2D locus conferring wheat yellow mosaic virus resistance is an exotic introgression and we developed 11 diagnostic markers tightly linked to QYm.nau-2D. Wheat yellow mosaic virus (WYMV) is a serious disease of winter wheat in China. Breeding resistant varieties is the most effective strategy for WYMV control. A WYMV resistant locus QYm.nau-2D on the chromosome arm 2DL has been repeatedly reported but the mapped region is large. In the present study, we screened recombinants using a biparental population and mapped QYm.nau-2D into an 18.8 Mb physical interval. By genome-wide association studies of 372 wheat varieties for WYMV resistance in four environments, we narrowed down QYm.nau-2D into a 16.4 Mb interval. Haplotype analysis indicated QYm.nau-2D were present as six different states due to recombination during hybridization breeding. QYm.nau-2D was finally mapped into a linkage block of 11.2 Mb. Chromosome painting using 2D specific probes and collinearity analysis among the published sequences corresponding to QYm.nau-2D region indicated the block was an exotic introgression. The Illumina-sequenced reads of four diploid Aegilops species were mapped to the sequence of Fielder, a variety having the introgression. The mapping reads were significantly increased at the putative introgression regions of Fielder. Ae. uniaristata (NN) had the highest mapping reads, suggesting that QYm.nau-2D was possibly an introgression from genome N. We investigated the agronomic performances of different haplotypes and observed no linkage drag of the alien introgression for the 15 tested traits. For marker-assisted selection of QYm.nau-2D, we developed 11 diagnostic markers tightly linked to the locus. This research provided a case study of an exotic introgression, which has been utilized in wheat improvement for WYMV resistance.


Assuntos
Vírus do Mosaico , Potyviridae , Triticum/genética , Mapeamento Cromossômico , Marcadores Genéticos , Resistência à Doença/genética , Estudo de Associação Genômica Ampla , Doenças das Plantas/genética , Melhoramento Vegetal
3.
J Opt Soc Am A Opt Image Sci Vis ; 40(2): 211-215, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36821190

RESUMO

It is known that the cumbersome 2π correction is needed in the traditional module-2π method (i.e., the phase wrapping method) due to the 2π deviation of the phase modulation depth of spatial light modulators (SLMs). To avoid the cumbersome 2π correction in the module-2π method, this paper proposes a module-n π method, and it can directly utilize any full-field phase modulation depth. First, for a Gaussian phase with a phase depth of 30 rad, wrapped by the module-3.6π, it is reconstructed with the root-mean-square (RMS) values of its phase response are 0.1006λ (for the Twyman-Green interferometer) and 0.1101λ (for the Shack-Hartmann wavefront sensor method), respectively, which proves that the monitoring accuracy is relatively consistent. Subsequently, some comparative experiments based on the traditional module-2π are performed. The experimental results show that the RMS values of its phase response are 0.8886λ (for a modulation depth of 11.3 rad) and 0.2261λ (for a modulation depth of 6.28 rad), respectively. All the results have proved that the SLM with a phase modulation depth exceeding 2π (e.g., 11.3 rad) has more prominent advantages. More specifically, increasing the SLM's phase modulation depth can effectively reduce the fringe orders of the wrapped patterns generated by the module-n π method. With the further reduction of the fringe orders, the influence of the fly-back zone error on the wavefront phase modulation is reduced, that is, the modulation accuracy is improved (the RMS values are reduced from 0.2261λ to 0.1006λ). Different from the traditional module-2π method, there is no need to consider the problems of the SLMs' over modulation or the insufficient modulation in the module-n π method. Furthermore, it avoids the cumbersome 2π correction process, which will make the use of the SLM more convenient.

4.
Plant Cell Environ ; 45(6): 1843-1861, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35199374

RESUMO

Stomatal movement participates in plant immunity by directly affecting the invasion of bacteria, but the genes that regulate stomatal immunity have not been well identified. Here, we characterised the function of the bZIP59 transcription factor from Arabidopsis thaliana, which is constitutively expressed in guard cells. The bzip59 mutant is partially impaired in stomatal closure induced by Pseudomonas syringae pv. tomato strain (Pst) DC3000 and is more susceptible to Pst DC3000 infection. By contrast, the line overexpressing bZIP59 enhances resistance to Pst DC3000 infection. Furthermore, the bzip59 mutant is also partially impaired in stomatal closure induced by flagellin flg22 derived from Pst DC3000, and epistasis analysis revealed that bZIP59 acts upstream of reactive oxygen species (ROS) and nitric oxide (NO) and downstream of salicylic acid signalling in flg22-induced stomatal closure. In addition, the bzip59 mutant showed resistance and sensitivity to Sclerotinia sclerotiorum and Tobacco mosaic virus that do not invade through stomata, respectively. Collectively, our results demonstrate that bZIP59 plays an important role in the stomatal immunity and reveal that the same transcription factor can positively and negatively regulate disease resistance against different pathogens.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Fatores de Transcrição de Zíper de Leucina Básica , Solanum lycopersicum , Arabidopsis/genética , Arabidopsis/imunologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/imunologia , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/imunologia , Solanum lycopersicum/metabolismo , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Imunidade Vegetal , Estômatos de Plantas/genética , Estômatos de Plantas/imunologia , Pseudomonas syringae/fisiologia , Fatores de Transcrição/genética
5.
Appl Opt ; 61(16): 4796-4801, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36255962

RESUMO

It is known that the phase response of spatial light modulators (SLMs) measured by double-beam interferometers is sensitive to mechanical and environmental disturbances. This paper proposes a Shack-Hartmann wavefront sensor (SHWS) method to measure the phase response characteristics of the SLM. The results show that the phase modulation depth measured by the proposed method is 1.7581λ, and 1.7993λ by the Twyman-Green interferometer method. The difference in the phase modulation depth between the two methods is only 0.0412λ, and its relative error rate is 2.29%. It proves that the phase modulation accuracy obtained by the SHWS with lenslets of 73*73 used in this paper is equivalent to that of the Twyman-Green interferometer. Compared with the interferometer method, the SHWS method is simple, compact, and robust, has good real-time performance, and is relatively vibration insensitive. In the future, the SHWS method will play a more important role in the detection of the SLM's phase response.

6.
Physiol Plant ; 172(4): 1908-1918, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33755206

RESUMO

Xylooligosaccharides (XOS) are the major coproducts of biofuel production and the most representative functional sugar enhancing animal physiology. However, little is known regarding the biological relevance of XOS to plants. Here, we found XOS triggered stomatal closure in Arabidopsis in a dose-dependent manner. Pamarcological data showed that XOS-induced stomatal closure was markedly inhibited by catalase (CAT, a reactive oxygen species [ROS] scavenger), salicylhydroxamic acid (SHAM, a peroxidase inhibitor), and 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO, a nitric oxide [NO] scavenger). Moreover, XOS induced the production of ROS and NO in guard cells of Arabidopsis. ROS production was strongly restricted by CAT and SHAM, but was unaffected by treatment with diphenyleneiodonium chloride (DPI, an NADPH oxidase inhibitor) or cPTIO. NO production was suppressed by CAT, SHAM, and cPTIO, but not by DPI. The elevation of ROS level mediated by SHAM-sensitive peroxidases occurred upstream of NO. Additionally, XOS-triggered stomatal closure and ROS and NO accumulation were significantly impaired in npr1 (salicylic acid signaling) mutant plants, but were not in jar1 (jasmonic acid signaling) or ein2 (ethylene signaling) mutant plants. Furthermore, XOS-induced stomatal closure was unaffected in both ost1 and atrbohD atrbohF (abscisic acid [ABA] signaling) mutant plants. Therefore, these results indicated that the biotic sugar, XOS, can elicit stomatal closure via salicylic acid signaling-mediated production of ROS and NO, in a manner independent of ABA signaling.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Ácido Abscísico , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Glucuronatos , Óxido Nítrico , Oligossacarídeos , Estômatos de Plantas , Espécies Reativas de Oxigênio , Ácido Salicílico/farmacologia
7.
Int J Mol Sci ; 22(7)2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33808261

RESUMO

In host-parasitoid interactions, antagonistic relationship drives parasitoids to vary in virulence in facing different hosts, which makes these systems excellent models for stress-induced evolutionary studies. Venom compositions varied between two strains of Tetrastichus brontispae, Tb-Bl and Tb-On. Tb-Bl targets Brontispa longissima pupae as hosts, and Tb-On is a sub-population of Tb-Bl, which has been experimentally adapted to a new host, Octodonta nipae. Aiming to examine variation in parasitoid virulence of the two strains toward two hosts, we used reciprocal injection experiments to compare effect of venom/ovarian fluids from the two strains on cytotoxicity, inhibition of immunity and fat body lysis of the two hosts. We found that Tb-Onvenom was more virulent towards plasmatocyte spreading, granulocyte function and phenoloxidase activity than Tb-Blvenom. Tb-Blovary was able to suppress encapsulation and phagocytosis in both hosts; however, Tb-Onovary inhibition targeted only B. longissima. Our data suggest that the venom undergoes rapid evolution when facing different hosts, and that the wasp has good evolutionary plasticity.


Assuntos
Besouros/parasitologia , Especificidade de Hospedeiro/genética , Interações Hospedeiro-Parasita/fisiologia , Animais , Evolução Molecular , Himenópteros/fisiologia , Fagocitose/fisiologia , Pupa/parasitologia , Virulência , Vespas/fisiologia
8.
Int J Mol Sci ; 21(15)2020 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-32722456

RESUMO

Intercropping improves land utilization with more crops grown together; however, shorter crops in intercropping experience stress, being shaded by the taller crops. Systematic changes in phenotype, physiology, yield, and gene regulation under shade stress in peanut are largely unknown, although shade responses have been well analyzed in model plants. We exposed peanut plants to simulated 40% and 80% shade for 15 and 30 days at the seedling stage, flowering stage, and both stages. Shade caused the increased elongation growth of the main stem, internode, and leaf, and elongation was positively associated with auxin levels. Shade stress reduced peanut yield. Further comparative RNA-seq analyses revealed expressional changes in many metabolism pathways and common core sets of expressional regulations in all shade treatments. Expressional downregulation of most genes for light-harvesting and photosynthesis agreed with the observed decreased parameters of photosynthesis processes. Other major regulations included expressional downregulation of most core genes in the sucrose and starch metabolism, and growth-promoting genes in plant hormone signal pathways. Together, the results advance our understanding of physiological and molecular regulation in shade avoidance in peanut, which could guide the breeding designing in the intercropping system.


Assuntos
Arachis/crescimento & desenvolvimento , Produtos Agrícolas/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Fotossíntese , Plântula/crescimento & desenvolvimento , Estresse Fisiológico , Sacarose/metabolismo
9.
Int J Mol Sci ; 21(5)2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32111099

RESUMO

External secretions, composed of a variety of chemical components, are among the most important traits that endow insects with the ability to defend themselves against predators, parasites, or other adversities, especially pathogens. Thus, these exudates play a crucial role in external immunity. Red palm weevil larvae are prolific in this regard, producing large quantities of p-benzoquinone, which is present in their oral secretion. Benzoquinone with antimicrobial activity has been proven to be an active ingredient and key factor for external immunity in a previous study. To obtain a better understanding of the genetic and molecular basis of external immune secretions, we identify genes necessary for p-benzoquinone synthesis. Three novel ARSB genes, namely, RfARSB-0311, RfARSB-11581, and RfARSB-14322, are screened, isolated, and molecularly characterized on the basis of transcriptome data. To determine whether these genes are highly and specifically expressed in the secretory gland, we perform tissue/organ-specific expression profile analysis. The functions of these genes are further determined by examining the antimicrobial activity of the secretions and quantification of p-benzoquinone after RNAi. All the results reveal that the ARSB gene family can regulate the secretory volume of p-benzoquinone by participating in the biosynthesis of quinones, thus altering the host's external immune inhibitory efficiency.


Assuntos
Benzoquinonas/metabolismo , Larva/genética , Larva/metabolismo , N-Acetilgalactosamina-4-Sulfatase/genética , N-Acetilgalactosamina-4-Sulfatase/metabolismo , Gorgulhos/genética , Gorgulhos/imunologia , Animais , Líquidos Corporais/imunologia , Imunidade , Insetos/genética , Larva/imunologia , Interferência de RNA , Glândulas Salivares/imunologia , Glândulas Salivares/metabolismo , Transcriptoma
10.
Plant Physiol ; 177(1): 285-299, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29523711

RESUMO

Early endosperm development presents a unique system in which to uncover epigenetic regulatory mechanisms because the contributing maternal and paternal genomes possess differential epigenetic modifications. In Arabidopsis (Arabidopsis thaliana), the initiation of endosperm coenocytic growth upon fertilization and the transition to endosperm cellularization are regulated by the FERTILIZATION-INDEPENDENT SEED (FIS)-Polycomb Repressive Complex 2 (PRC2), a putative H3K27 methyltransferase. Here, we address the possible role of the FIS-PRC2 complex in regulating the type I MADS-box gene family, which has been shown previously to regulate early endosperm development. We show that a subclass of type I MADS-box genes (C2 genes) was expressed in distinct domains of the coenocytic endosperm in wild-type seeds. Furthermore, the C2 genes were mostly up-regulated biallelically during the extended coenocytic phase of endosperm development in the FIS-PRC2 mutant background. Using allele-specific expression analysis, we also identified a small subset of C2 genes subjected to FIS-PRC2-dependent maternal or FIS-PRC2-independent paternal imprinting. Our data support a dual role for the FIS-PRC2 complex in the regulation of C2 type I MADS-box genes, as evidenced by a generalized role in the repression of gene expression at both alleles associated with endosperm cellularization and a specialized role in silencing the maternal allele of imprinted genes.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/embriologia , Arabidopsis/genética , Endosperma/embriologia , Endosperma/genética , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Proteínas de Domínio MADS/genética , Complexo Repressor Polycomb 2/metabolismo , Fatores de Transcrição/metabolismo , Região 5'-Flanqueadora/genética , Alelos , Proteínas de Arabidopsis/genética , Regulação para Baixo/genética , Fertilização , Genes de Plantas , Impressão Genômica , Proteínas de Domínio MADS/metabolismo , Óvulo Vegetal/genética , Complexo Repressor Polycomb 2/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fatores de Transcrição/genética
11.
Artigo em Inglês | MEDLINE | ID: mdl-28990217

RESUMO

A typical characteristic of the insect innate immune system is the activation of the serine protease cascade in the hemolymph. As being the terminal component of the extracellular serine protease cascade in the prophenoloxidase (proPO) activating system, proPO-activating factors (PPAFs) activated by the upstream cascade may generate active phenoloxidase, which then induces downstream melanization. In the present study, we reported three PPAFs from the nipa palm hispid beetle Octodonta nipae (Maulik) (designated as OnPPAF1, OnPPAF2, OnPPAF3). All three OnPPAFs contained a single clip domain at the amino-terminus followed by a trypsin-like serine protease domain at the carboxyl-terminus, except the Ser in the active sites of OnPPAF2 and OnPPAF3 was substituted with Gly. Transcript expression analysis revealed that all OnPPAFs were highly expressed in hemolymph, whereas OnPPAF2 showed an extremely low mRNA abundance compared with that of OnPPAF1 and OnPPAF3, and that the abundance of all three OnPPAFs was dramatically increased upon bacterial challenge. Knockdown of OnPPAF1 or OnPPAF3 resulted in a reduction of hemolymph phenoloxidase activity and an inhibition of hemolymph melanization, whereas the knockdown of OnPPAF2 did not affect the proPO cascade. Our work thus implies that the three OnPPAFs may have different functions and regulation during immune responses in O. nipae.


Assuntos
Catecol Oxidase/metabolismo , Besouros/metabolismo , Precursores Enzimáticos/metabolismo , Serina Endopeptidases/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Besouros/genética , Besouros/imunologia , Expressão Gênica , Hemolinfa/enzimologia , Imunidade Inata , Proteínas de Insetos/metabolismo , Melaninas/metabolismo , Filogenia , Interferência de RNA , Serina Endopeptidases/genética , Serina Proteases/metabolismo
12.
J Tradit Chin Med ; 37(2): 193-200, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-29960291

RESUMO

OBJECTIVE: To evaluate the effectiveness and safety of cervical spondylosis formula granules in reducing the symptoms of patients with the nerve root type and the vertebral artery type of cervical spondylosis. METHODS: This was a multicenter, single-blind, randomized, controlled trial. From April 2002 to November 2003, 499 patients were randomly assigned to either the treatment or the control group. The treatment group was orally administered granules prepared with a formula for cervical spondylosis, while the control group was given Jingfukang granules. The treatment course was 1 month for both groups. RESULTS: In patients with the nerve root type of cervical spondylosis, the total effect rate in the treatment group (87.21% ) was significantly higher than that in the control group (80.70%, P < 0.01). After the treatment period in both groups, the treatment group had a significantly greater rate of resolution of pain, numbness of the upper limbs, muscle strength of the upper limbs, and fatigue than the control group (all P < 0.05). In patients with the vertebral artery type of cervical spondylosis, the total effect rate in the treatment group (82.07%) was similar to that in the control group (71.21% , P > 0.05). After the treatment period in both groups, the treatment group had a significantly greater rate of resolution of weakness of the waist and knees than the control group (P < 0.05). CONCLUSION: The cervical spondylosis formula granules significantly improve numbness, muscle strength, and fatigue, and reduce pain in patients with the nerve root type of cervical spondylosis, and improve the weakness of the waist and knees in patients with the vertebral artery type of cervical spondylosis.


Assuntos
Medicamentos de Ervas Chinesas/administração & dosagem , Espondilose/tratamento farmacológico , Adulto , Idoso , Feminino , Humanos , Dor Lombar/tratamento farmacológico , Dor Lombar/fisiopatologia , Masculino , Pessoa de Meia-Idade , Força Muscular , Método Simples-Cego , Raízes Nervosas Espinhais/efeitos dos fármacos , Raízes Nervosas Espinhais/fisiopatologia , Espondilose/fisiopatologia , Resultado do Tratamento , Artéria Vertebral/efeitos dos fármacos , Artéria Vertebral/fisiopatologia
13.
Plant Cell Physiol ; 57(12): 2472-2484, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27649734

RESUMO

SsCut, which functions as an elicitor, can induce plant immunity. In this study, we utilized Nicotiana benthamiana and virus-induced gene silencing to decrease the expression of > 2,500 genes individually. Using this forward genetics approach, several genes were identified that, when silenced, compromised SsCut-triggered cell death based on a cell death assay. A C2H2-type zinc finger gene was isolated from N. benthamiana Sequence analysis indicated that the gene encodes a 27 kDa protein with 253 amino acids containing two typical C2H2-type zinc finger domains; this gene was named NbCZF1 We found that SsCut-induced cell death could be inhibited by virus-induced gene silencing of NbCZF1 in N. benthamiana In addition, SsCut induces stomatal closure, accompanied by reactive oxygen species (ROS) production by NADPH oxidases and nitric oxide (NO) production. NbCZF1-silenced plants showed impaired SsCut-induced stomatal closure, decreased SsCut-induced production of ROS and NO in guard cells and reduced SsCut-induced resistance against Phytophthora nicotianae Taken together, these results demonstrate that the NbCZF1-ROS-NO pathway mediates multiple SsCut-triggered responses, including stomatal closure, hypersensitive responses and defense-related gene expression. This is the first report describing the function of a C2H2-type zinc finger protein in N. benthamiana.


Assuntos
Nicotiana/genética , Phytophthora/fisiologia , Doenças das Plantas/imunologia , Imunidade Vegetal , Proteínas de Plantas/metabolismo , Transdução de Sinais , Sequência de Aminoácidos , Dedos de Zinco CYS2-HIS2 , Morte Celular , Regulação da Expressão Gênica de Plantas , Inativação Gênica , Óxido Nítrico/metabolismo , Filogenia , Folhas de Planta/citologia , Folhas de Planta/genética , Folhas de Planta/imunologia , Folhas de Planta/fisiologia , Proteínas de Plantas/genética , Estômatos de Plantas/citologia , Estômatos de Plantas/genética , Estômatos de Plantas/imunologia , Estômatos de Plantas/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA , Nicotiana/citologia , Nicotiana/imunologia , Nicotiana/fisiologia
14.
J Exp Bot ; 67(1): 131-41, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26466663

RESUMO

MADS-box transcription factor genes are well known for their role in floral organ and seed development. In this study, a novel MADS-box-containing gene, designated NbMADS1, was isolated from leaves of Nicotiana benthamiana. The full-length cDNA was 666 bp and encoded a putative polypeptide of 221 aa with a mass of 24.3 kDa. To assess the role of NbMADS1 in the defence response to bacterial harpin(Xoo), an elicitor of the hypersensitive response, a loss-of-function experiment was performed in N. benthamiana plants using virus-induced gene silencing. Analyses of electrolyte leakage revealed more extensive cell death in the control plants than in NbMADS1-silenced plants. The NbMADS1-silenced plants showed impaired harpin(Xoo)-induced stomatal closure, decreased harpin(Xoo)-induced production of hydrogen peroxide (H2O2) and nitric oxide (NO) in guard cells, and reduced harpin(Xoo)-induced resistance to Phytophthora nicotianae. The compromised stomatal closure observed in the NbMADS1-silenced plants was inhibited by the application of H2O2 and sodium nitroprusside (an NO donor). Taken together, these results demonstrate that the NbMADS1-H2O2-NO pathway mediates multiple harpin(Xoo)-triggered responses, including stomatal closure, hypersensitive cell death, and defence-related gene expression, suggesting that NbMADS1 plays an important role in regulating the response to harpin(Xoo) in N. benthamiana plants.


Assuntos
Proteínas de Domínio MADS/genética , Nicotiana/genética , Nicotiana/microbiologia , Phytophthora/fisiologia , Imunidade Vegetal , Proteínas de Plantas/genética , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/metabolismo , Morte Celular , DNA Complementar/genética , DNA Complementar/metabolismo , Proteínas de Domínio MADS/metabolismo , Dados de Sequência Molecular , Filogenia , Proteínas de Plantas/metabolismo , Estômatos de Plantas/fisiologia , Análise de Sequência de DNA , Nicotiana/imunologia , Nicotiana/metabolismo , Xanthomonas/genética , Xanthomonas/fisiologia
15.
Mycologia ; 107(6): 1130-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26297780

RESUMO

Sclerotinia sclerotiorum is a necrotrophic plant-pathogenic fungus that infects more than 400 species of plants. In this study the nascent polypeptide-associated complex α subunit gene of S. sclerotiorum (SsNACα; accession No. XP_001593856.1) was cloned and characterized. The relative transcript expression of SsNACα at different morphological stages of asexual development of S. sclerotiorum were analyzed by quantitative real time PCR (qRT-PCR). RNAi-mediated gene silencing was successful for SsNACα, and the mutated strains exhibited less than 15% of the relative expression of SsNACα were obtained and used for studying the biological functions of the gene. A delay in sclerotial maturation for S. sclerotiorum was observed in the SsNACα mutants. The significant elevations for both the activities of pectin-degrading enzymes and the expression of polygalacturonase genes also were associated with the mutated strains, indicating that SsNACα could negatively influence polygalacturonases expression and modulate the pathogenicity of S. sclerotiorum.


Assuntos
Ascomicetos/enzimologia , Ascomicetos/patogenicidade , Proteínas Fúngicas/genética , Regulação Enzimológica da Expressão Gênica , Chaperonas Moleculares/metabolismo , Doenças das Plantas/microbiologia , Poligalacturonase/genética , Ascomicetos/genética , Ascomicetos/metabolismo , Brassica rapa/microbiologia , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Chaperonas Moleculares/genética , Poligalacturonase/metabolismo , Nicotiana/microbiologia , Virulência
16.
Plant Mol Biol ; 86(4-5): 495-511, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25149470

RESUMO

In this study, we report the cloning of the SsCut gene encoding cutinase from Sclerotinia sclerotiorum. We isolated a 609-bp cDNA encoding a polypeptide of 202 amino acids with a molecular weight of 20.4 kDa. Heterologous expression of SsCut in Escherichia coli (His-SsCut) caused the formation of lesions in tobacco that closely resembled hypersensitive response lesions. Mutational analysis identified the C-terminal-half peptide and the same amino acids indispensable for both enzyme and elicitor activity. His-SsCut was caused cell death in Arabidopsis, soybean (Glycine max), oilseed rape (Brassica napus), rice (Oryza sativa), maize (Zea mays), and wheat (Triticum aestivum), indicating that both dicot and monocot species are responsive to the elicitor. Furthermore, the elicitation of tobacco was effective in the induction of the activities of hydrogen peroxide, phenylalanine ammonia-lyase, peroxides, and polyphenol oxidase. His-SsCut-treated plants exhibited enhanced resistance as indicated by a significant reduction in the number and size of S. sclerotiorum, Phytophthora sojae, and P. nicotianae lesions on leaves relative to controls. Real-time PCR results indicated that the expression of defense-related genes and genes involved in signal transduction were induced by His-SsCut. Our results demonstrate that SsCut is an elicitor that triggers defense responses in plants and will help to clarify its relationship to downstream signaling pathways that induce defense responses.


Assuntos
Ascomicetos/genética , Hidrolases de Éster Carboxílico/genética , Proteínas Fúngicas/genética , Doenças das Plantas/genética , Plantas/genética , Sequência de Aminoácidos , Ascomicetos/metabolismo , Ascomicetos/fisiologia , Hidrolases de Éster Carboxílico/classificação , Hidrolases de Éster Carboxílico/metabolismo , Catecol Oxidase/metabolismo , Resistência à Doença/genética , Eletroforese em Gel de Poliacrilamida , Proteínas Fúngicas/metabolismo , Regulação da Expressão Gênica de Plantas , Interações Hospedeiro-Patógeno , Dados de Sequência Molecular , Fenilalanina Amônia-Liase/metabolismo , Filogenia , Doenças das Plantas/microbiologia , Folhas de Planta/genética , Folhas de Planta/metabolismo , Folhas de Planta/microbiologia , Plantas/microbiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência de Aminoácidos , Fatores de Tempo , Nicotiana/genética , Nicotiana/metabolismo , Nicotiana/microbiologia
17.
J Exp Bot ; 65(9): 2483-94, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24723400

RESUMO

Previously, it was found that Nep1Mo (a Nep1-like protein from Magnaporthe oryzae) could trigger a variety of plant responses, including stomatal closure, hypersensitive cell death (HCD), and defence-related gene expression, in Nicotiana benthamiana. In this study, it was found that Nep1Mo-induced cell death could be inhibited by the virus-induced gene silencing of NbALY916 in N. benthamiana. NbALY916-silenced plants showed impaired Nep1Mo-induced stomatal closure, decreased Nep1Mo-induced production of hydrogen peroxide (H2O2) and nitric oxide (NO) in guard cells, and reduced Nep1Mo-induced resistance against Phytophthora nicotianae. It also found that the deletion of AtALY4, an orthologue of NbALY916 in Arabidopsis thaliana, impaired Nep1Mo-triggered stomatal closure, HCD, and defence-related gene expression. The compromised stomatal closure observed in the NbALY916-silenced plants and AtALY4 mutants was inhibited by the application of H2O2 and sodium nitroprusside (an NO donor), and both Nep1Mo and H2O2 stimulated guard cell NO synthesis. Conversely, NO-induced stomatal closure was found not to require H2O2 synthesis; and NO treatment did not induce H2O2 production in guard cells. Taken together, these results demonstrate that the NbAlY916/AtAlY4-H2O2-NO pathway mediates multiple Nep1Mo-triggered responses, including stomatal closure, HCD, and defence-related gene expression.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/microbiologia , Proteínas Fúngicas/metabolismo , Magnaporthe/metabolismo , Nicotiana/microbiologia , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Morte Celular , Proteínas Fúngicas/genética , Regulação da Expressão Gênica de Plantas , Peróxido de Hidrogênio/metabolismo , Magnaporthe/genética , Óxido Nítrico/metabolismo , Estômatos de Plantas/citologia , Estômatos de Plantas/genética , Estômatos de Plantas/metabolismo , Nicotiana/genética , Nicotiana/metabolismo
18.
Int J Biol Macromol ; 257(Pt 1): 128575, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38048930

RESUMO

Plant pathogens secrete fungal-specific common in several fungal extracellular membrane (CFEM) effectors to manipulate host immunity and contribute to their virulence. Little is known about effectors and their functions in Alternaria solani, the necrotrophic fungal pathogen causing potato early blight. To identify candidate CFEM effector genes, we mined A. solani genome databases. This led to the identification of 12 genes encoding CFEM proteins (termed AsCFEM1-AsCFEM12) and 6 of them were confirmed to be putative secreted effectors. In planta expression revealed that AsCFEM6 and AsCFEM12 have elicitor function that triggers plant defense response including cell death in different botanical families. Targeted gene disruption of AsCFEM6 and AsCFEM12 resulted in a change in spore development, significant reduction of virulence on potato and eggplant susceptible cultivars, increased resistance to fungicide stress, variation in iron acquisition and utilization, and the involvement in 1,8-dihydroxynaphthalene (DHN) melanin biosynthesis pathway. Using maximum likelihood method, we found that positive selection likely caused the polymorphism within AsCFEM6 and AsCFEM12 homologs in different Alternaria spp. Site-directed mutagenesis analysis indicated that positive selection sites within their CFEM domains are required for cell death induction in Nicotiana benthamiana and are critical for response to abiotic stress in yeast. These results demonstrate that AsCFEM effectors possess additional functions beyond their roles in host plant immune response and pathogen virulence.


Assuntos
Alternaria , Solanum tuberosum , Alternaria/fisiologia , Genes Fúngicos , Doenças das Plantas/microbiologia , Solanum tuberosum/genética , Solanum tuberosum/microbiologia , Virulência/genética
19.
Sci Prog ; 107(2): 368504241257389, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38881338

RESUMO

As the Internet and Internet of Things (IoT) continue to develop, Heterogeneous Information Networks (HIN) have formed complex interaction relationships among data objects. These relationships are represented by various types of edges (meta-paths) that contain rich semantic information. In the context of IoT data applications, the widespread adoption of Trigger-Action Patterns makes the management and analysis of heterogeneous data particularly important. This study proposes a meta-path-based clustering method for heterogeneous IoT data called I-RankClus, which aims to improve the modeling and analysis efficiency of IoT data. By combining ranking with clustering algorithms, the PageRank algorithm was used to calculate the intraclass influence of objects in the network. The HITS algorithm then transfers the influence to the core objects, thereby optimizing the classification of objects during the clustering process. The I-RankClus algorithm does not process each meta-path individually, but instead integrates multiple meta-paths to enhance the interpretability and clustering performance of the model. The experimental results show that the I-RankClus algorithm can process complex IoT datasets more effectively than traditional clustering methods and provide more accurate clustering outcomes. Furthermore, through a detailed analysis of meta-paths, this study explored the influence and importance of different meta-paths, thereby validating the effectiveness of the algorithm. Overall, the research presented in this paper not only improves the application effects of HINs in IoT data analysis but also provides valuable methods and insights for future network data processing.

20.
Mol Plant Pathol ; 25(2): e13438, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38393695

RESUMO

Pectin has been extensively studied in animal immunity, and exogenous pectin as a food additive can provide protection against inflammatory bowel disease. However, the utility of pectin to improve immunity in plants is still unstudied. Here, we found exogenous application of pectin triggered stomatal closure in Arabidopsis in a dose- and time-dependent manner. Additionally, pectin activated peroxidase and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase to produce reactive oxygen species (ROS), which subsequently increased cytoplasmic Ca2+ concentration ([Ca2+ ]cyt ) and was followed by nitric oxide (NO) production, leading to stomatal closure in an abscisic acid (ABA) and salicylic acid (SA) signalling-dependent mechanism. Furthermore, pectin enhanced the disease resistance to Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) with mitogen-activated protein kinases (MPKs) MPK3/6 activated and upregulated expression of defence-responsive genes in Arabidopsis. These results suggested that exogenous pectin-induced stomatal closure was associated with ROS and NO production regulated by ABA and SA signalling, contributing to defence against Pst DC3000 in Arabidopsis.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Pectinas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Estômatos de Plantas/genética , Ácido Abscísico/farmacologia , Ácido Abscísico/metabolismo
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