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Medicago truncatula is a model legume for fundamental research on legume biology and symbiotic nitrogen fixation. Tnt1, a retrotransposon from tobacco, was used to generate insertion mutants in M. truncatula R108. Approximately 21 000 insertion lines have been generated and publicly available. Tnt1 retro-transposition event occurs during somatic embryogenesis (SE), a pivotal process that triggers massive methylation changes. We studied the SE of M. truncatula R108 using leaf explants and explored the dynamic shifts in the methylation landscape from leaf explants to callus formation and finally embryogenesis. Higher cytosine methylation in all three contexts of CG, CHG, and CHH patterns was observed during SE compared to the controls. Higher methylation patterns were observed in assumed promoter regions (~2-kb upstream regions of transcription start site) of the genes, while lowest was recorded in the untranslated regions. Differentially methylated promoter region analysis showed a higher CHH methylation in embryogenesis tissue samples when compared to CG and CHG methylation. Strong correlation (89.71%) was identified between the differentially methylated regions (DMRs) and the site of Tnt1 insertions in M. truncatula R108 and stronger hypermethylation of genes correlated with higher number of Tnt1 insertions in all contexts of CG, CHG, and CHH methylation. Gene ontology enrichment and KEGG pathway enrichment analysis identified genes and pathways enriched in the signal peptide processing, ATP hydrolysis, RNA polymerase activity, transport, secondary metabolites, and nitrogen metabolism pathways. Combined gene expression analysis and methylation profiling showed an inverse relationship between methylation in the DMRs (regions spanning genes) and the expression of genes. Our results show that a dynamic shift in methylation happens during the SE process in the context of CG, CHH and CHG methylation, and the Tnt1 retrotransposition correlates with the hyperactive methylation regions.
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Metilação de DNA , Regulação da Expressão Gênica de Plantas , Medicago truncatula , Técnicas de Embriogênese Somática de Plantas , Retroelementos , Medicago truncatula/genética , Medicago truncatula/metabolismo , Retroelementos/genética , Genoma de Planta/genética , Regiões Promotoras Genéticas/genéticaRESUMO
The conservation of GOLVEN (GLV)/ROOT MERISTEM GROWTH FACTOR (RGF) peptide encoding genes across plant genomes capable of forming roots or root-like structures underscores their potential significance in the terrestrial adaptation of plants. This study investigates the function and role of GOLVEN peptide-coding genes in Medicago truncatula. Five out of fifteen GLV/RGF genes were notably upregulated during nodule organogenesis and were differentially responsive to nitrogen deficiency and auxin treatment. Specifically, the expression of MtGLV9 and MtGLV10 at nodule initiation sites was contingent upon the NODULE INCEPTION transcription factor. Overexpression of these five nodule-induced GLV genes in hairy roots of M. truncatula and application of their synthetic peptide analogues led to a decrease in nodule count by 25-50%. Uniquely, the GOLVEN10 peptide altered the positioning of the first formed lateral root and nodule on the primary root axis, an observation we term 'noduletaxis'; this decreased the length of the lateral organ formation zone on roots. Histological section of roots treated with synthetic GOLVEN10 peptide revealed an increased cell number within the root cortical cell layers without a corresponding increase in cell length, leading to an elongation of the root likely introducing a spatiotemporal delay in organ formation. At the transcription level, the GOLVEN10 peptide suppressed expression of microtubule-related genes and exerted its effects by changing expression of a large subset of Auxin responsive genes. These findings advance our understanding of the molecular mechanisms by which GOLVEN peptides modulate root morphology, nodule ontogeny, and interactions with key transcriptional pathways.
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Regulação da Expressão Gênica de Plantas , Medicago truncatula , Proteínas de Plantas , Raízes de Plantas , Nódulos Radiculares de Plantas , Medicago truncatula/genética , Medicago truncatula/crescimento & desenvolvimento , Medicago truncatula/metabolismo , Medicago truncatula/efeitos dos fármacos , Medicago truncatula/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/genética , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Nódulos Radiculares de Plantas/genética , Nódulos Radiculares de Plantas/crescimento & desenvolvimento , Nódulos Radiculares de Plantas/metabolismo , Nódulos Radiculares de Plantas/efeitos dos fármacos , Ácidos Indolacéticos/metabolismo , Ácidos Indolacéticos/farmacologia , Nodulação/genética , Meristema/genética , Meristema/crescimento & desenvolvimento , Meristema/efeitos dos fármacos , Peptídeos/metabolismo , Peptídeos/genéticaRESUMO
Background: No study has examined whether serum uric acid/creatinine (sUA/Cr) is associated with the newly defined metabolic-associated fatty liver disease (MAFLDs). Furthermore, studies on other factors influencing their relationship have not been conducted. Aim: To investigate the relationship between sUA/Cr and newly defined MAFLD, and to identify any factors that affect this relationship. Methods: We retrospectively reviewed the data of patients who underwent abdominal computed tomography (CT) at the Hospital Health Promotion Center. Participants were divided into the healthy (no evidence of liver disease; n = 707), MAFLD+non-heavy drinking (steatosis diagnosed by CT and drinking <140 and 70 grams/week for men and women, respectively; n = 291), and MAFLD+heavy drinking (fatty liver diagnosed by CT and drinking >140 and 70 grams/week for men and women, respectively; n = 61) groups. The relationship between sUA/Cr and MAFLD among the three groups were compared using multivariate logistic regression. Results: After adjusting for age, it was observed that when the sUA/Cr ratio increased by 1, the risk of MAFLD increased by 1.205 times the risk in the normal group. After adjusting for age, an increase by 1 in the sUA/Cr ratio increased the probability of non-heavy drinking+MAFLD and heavy drinking+MAFLD by 1.302 and 1.556 times, respectively, compared with healthy individuals. For those who smoked, the probability of heavy drinking+MAFLD was 9.901 times higher compared with healthy individuals. Conclusion: The newly defined MAFLD is related to sUA/Cr. The amount of alcohol consumption and smoking influenced the association between sUA/Cr and MAFLD.
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Fígado Gorduroso , Hepatopatia Gordurosa não Alcoólica , Creatinina , Fígado Gorduroso/diagnóstico por imagem , Fígado Gorduroso/epidemiologia , Feminino , Humanos , Masculino , Estudos Retrospectivos , Ácido ÚricoRESUMO
Nonhost disease resistance is the most common type of plant defense mechanism against potential pathogens. In the present study, the metabolic enzyme formate dehydrogenase 1 (FDH1) was identified to associate with nonhost disease resistance in Nicotiana benthamiana and Arabidopsis thaliana. In Arabidopsis, AtFDH1 was highly upregulated in response to both host and nonhost bacterial pathogens. The Atfdh1 mutants were compromised in nonhost resistance, basal resistance, and gene-for-gene resistance. The expression patterns of salicylic acid (SA) and jasmonic acid (JA) marker genes after pathogen infections in Atfdh1 mutant indicated that both SA and JA are involved in the FDH1-mediated plant defense response to both host and nonhost bacterial pathogens. Previous studies reported that FDH1 localizes to mitochondria, or both mitochondria and chloroplasts. Our results showed that the AtFDH1 mainly localized to mitochondria, and the expression level of FDH1 was drastically increased upon infection with host or nonhost pathogens. Furthermore, we identified the potential co-localization of mitochondria expressing FDH1 with chloroplasts after the infection with nonhost pathogens in Arabidopsis. This finding suggests the possible role of FDH1 in mitochondria and chloroplasts during defense responses against bacterial pathogens in plants.
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Proteínas de Arabidopsis , Arabidopsis , Resistência à Doença , Doenças das Plantas , Arabidopsis/enzimologia , Arabidopsis/microbiologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Ciclopentanos , Resistência à Doença/genética , Formiato Desidrogenases/genética , Regulação da Expressão Gênica de Plantas , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Pseudomonas syringae/metabolismo , Ácido Salicílico/metabolismo , NicotianaRESUMO
While urine-based liquid biopsy has expanded to the analyses of extracellular nucleic acids, the potential of transfer RNA (tRNA) encapsulated within extracellular vesicles has not been explored as a new class of urine biomarkers for kidney injury. Using rat kidney and mouse tubular cell injury models, we tested if extracellular vesicle-loaded tRNA and their m1A (N1-methyladenosine) modification reflect oxidative stress of kidney injury and determined the mechanism of tRNA packaging into extracellular vesicles. We determined a set of extracellular vesicle-loaded, isoaccepting tRNAs differentially released after ischemia-reperfusion injury and oxidative stress. Next, we found that m1A modification of extracellular vesicle tRNAs, despite an increase of the methylated tRNAs in intracellular vesicles, showed little or no change under oxidative stress. Mechanistically, oxidative stress decreases tRNA loading into intracellular vesicles while the tRNA-loaded vesicles are accumulated due to decreased release of the vesicles from the cell surface. Furthermore, Maf1-mediated transcriptional repression of the tRNAs decreases the cargo availability for extracellular vesicle release in response to oxidative stress. Taken together, our data support that release of extracellular vesicle tRNAs reflects oxidative stress of kidney tubules which might be useful to detect ischemic kidney injury and could lead to rebalance protein translation under oxidative stress.
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Injúria Renal Aguda/metabolismo , Vesículas Extracelulares/metabolismo , Isquemia/metabolismo , Rim/irrigação sanguínea , Rim/metabolismo , Estresse Oxidativo , RNA de Transferência/metabolismo , Injúria Renal Aguda/genética , Injúria Renal Aguda/patologia , Adenosina/análogos & derivados , Adenosina/metabolismo , Animais , Linhagem Celular , Modelos Animais de Doenças , Vesículas Extracelulares/genética , Vesículas Extracelulares/patologia , Isquemia/genética , Isquemia/patologia , Rim/patologia , Metilação , Camundongos , RNA de Transferência/genética , Ratos Sprague-Dawley , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Transcrição GênicaRESUMO
Many plant-encoded E3 ligases are known to be involved in plant defense. Here, we report a novel role of E3 ligase SALT- AND DROUGHT-INDUCED RING FINGER1 (SDIR1) in plant immunity. Even though SDIR1 is reasonably well-characterized, its role in biotic stress response is not known. The silencing of SDIR1 in Nicotiana benthamiana reduced the multiplication of the virulent bacterial pathogen Pseudomonas syringae pv. tabaci. The Arabidopsis sdir1 mutant is resistant to virulent pathogens, whereas SDIR1 overexpression lines are susceptible to both host and nonhost hemibiotrophic bacterial pathogens. However, sdir1 mutant and SDIR1 overexpression lines showed hypersusceptibility and resistance, respectively, against the necrotrophic pathogen Erwinia carotovora. The mutant of SDIR1 target protein, i.e., SDIR-interacting protein 1 (SDIR1P1), also showed resistance to host and nonhost pathogens. In SDIR1 overexpression plants, transcripts of NAC transcription factors were less accumulated and the levels of jasmonic acid (JA) and abscisic acid were increased. In the sdir1 mutant, JA signaling genes JAZ7 and JAZ8 were downregulated. These data suggest that SDIR1 is a susceptibility factor and its activation or overexpression enhances disease caused by P. syringae pv. tomato DC3000 in Arabidopsis. Our results show a novel role of SDIR1 in modulating plant defense gene expression and plant immunity.[Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
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Proteínas de Arabidopsis , Arabidopsis , Resistência à Doença , Interações Hospedeiro-Patógeno , Ubiquitina-Proteína Ligases , Arabidopsis/enzimologia , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas , Interações Hospedeiro-Patógeno/genética , Pectobacterium carotovorum/fisiologia , Doenças das Plantas/microbiologia , Pseudomonas syringae/fisiologia , Nicotiana/enzimologia , Nicotiana/microbiologia , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismoRESUMO
Interleukin-34 (IL-34) is an alternative ligand to colony-stimulating factor-1 (CSF-1) for the CSF-1 receptor that acts as a key regulator of monocyte/macrophage lineage. In this study, we show that tumor-derived IL-34 mediates resistance to immune checkpoint blockade regardless of CSF-1 existence in various murine cancer models. Consistent with its immunosuppressive characteristics, the expression of IL-34 in tumors correlates with decreased frequencies of cellular (such as CD8+ and CD4+ T cells and M1-biased macrophages) and molecular (including various cytokines and chemokines) effectors at the tumor microenvironment. Then, a neutralizing antibody against IL-34 improved the therapeutic effects of the immune checkpoint blockade in combinatorial therapeutic models, including a patient-derived xenograft model. Collectively, we revealed that tumor-derived IL-34 inhibits the efficacy of immune checkpoint blockade and proposed the utility of IL-34 blockade as a new strategy for cancer therapy.
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Iron-sulfur (Fe-S) clusters are inorganic cofactors that are present in all kingdoms of life as part of a large number of proteins involved in several cellular processes, including DNA replication and metabolism. In this work, we demonstrate an additional role for two Fe-S cluster genes in biotic stress responses in plants. Eleven Fe-S cluster genes, including the NITROGEN FIXATION S-LIKE1 (NFS1) and its interactor FRATAXIN (FH), when silenced in Nicotiana benthamiana, compromised nonhost resistance to Pseudomonas syringae pv. tomato T1. NbNFS1 expression was induced by pathogens and salicylic acid. Arabidopsis (Arabidopsis thaliana) atnfs and atfh mutants, with reduced AtNFS1 or AtFH gene expression, respectively, showed increased susceptibility to both host and nonhost pathogen infection. Arabidopsis AtNFS1 and AtFH overexpressor lines displayed decreased susceptibility to infection by host pathogen P syringae pv. tomato DC3000. The AtNFS1 overexpression line exhibited constitutive upregulation of several defense-related genes and enrichment of gene ontology terms related to immunity and salicylic acid responses. Our results demonstrate that NFS1 and its interactor FH are involved not only in nonhost resistance but also in basal resistance, suggesting a new role of the Fe-S cluster pathway in plant immunity.
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Arabidopsis/imunologia , Proteínas Ferro-Enxofre/metabolismo , Nicotiana/imunologia , Doenças das Plantas/imunologia , Imunidade Vegetal/genética , Imunidade Vegetal/imunologia , Pseudomonas syringae/patogenicidade , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Proteínas Ferro-Enxofre/genética , Doenças das Plantas/genética , Nicotiana/genética , Nicotiana/microbiologiaRESUMO
Ribosomes play an integral part in plant growth, development, and defence responses. We report here the role of ribosomal protein large (RPL) subunit QM/RPL10 in nonhost disease resistance. The RPL10-silenced Nicotiana benthamiana plants showed compromised disease resistance against nonhost pathogen Pseudomonas syringae pv. tomato T1. The RNA-sequencing analysis revealed that many genes involved in defence and protein translation mechanisms were differentially affected due to silencing of NbRPL10. Arabidopsis AtRPL10 RNAi and rpl10 mutant lines showed compromised nonhost disease resistance to P. syringae pv. tomato T1 and P. syringae pv. tabaci. Overexpression of AtRPL10A in Arabidopsis resulted in reduced susceptibility against host pathogen P. syringae pv. tomato DC3000. RPL10 interacts with the RNA recognition motif protein and ribosomal proteins RPL30, RPL23, and RPS30 in the yeast two-hybrid assay. Silencing or mutants of genes encoding these RPL10-interacting proteins in N. benthamiana or Arabidopsis, respectively, also showed compromised disease resistance to nonhost pathogens. These results suggest that QM/RPL10 positively regulates the defence and translation-associated genes during nonhost pathogen infection.
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Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Doenças das Plantas/imunologia , Pseudomonas syringae/patogenicidade , Proteína Ribossômica L10/metabolismo , Proteínas Ribossômicas/metabolismo , Solanum lycopersicum/microbiologia , Arabidopsis/imunologia , Arabidopsis/microbiologia , Proteínas de Arabidopsis/genética , Resistência à Doença/genética , Expressão Gênica , Mutação , Doenças das Plantas/microbiologia , Biossíntese de Proteínas , Interferência de RNA , Proteína Ribossômica L10/genética , Proteínas Ribossômicas/genética , Ribossomos/metabolismo , Análise de Sequência de RNA , Nicotiana/genética , Nicotiana/imunologia , Nicotiana/microbiologia , Técnicas do Sistema de Duplo-HíbridoRESUMO
BACKGROUND: Treatment of human lung squamous cell carcinoma (LUSC) using current targeted therapies is limited because of their diverse somatic mutations without any specific dominant driver mutations. These mutational diversities preventing the use of common targeted therapies or the combination of available therapeutic modalities would require a preclinical animal model of this tumor to acquire improved clinical responses. Patient-derived xenograft (PDX) models have been recognized as a potentially useful preclinical model for personalized precision medicine. However, whether the use of LUSC PDX models would be appropriate enough for clinical application is still controversial. METHODS: In the process of developing PDX models from Korean patients with LUSC, the authors investigated the factors influencing the successful initial engraftment of tumors in NOD scid gamma mice and the retainability of the pathological and genomic characteristics of the parental patient tumors in PDX tumors. CONCLUSIONS: The authors have developed 62 LUSC PDX models that retained the pathological and genomic features of parental patient tumors, which could be used in preclinical and co-clinical studies. Trial registration Tumor samples were obtained from 139 patients with LUSC between November 2014 and January 2019. All the patients provided signed informed consents. This study was approved by the institutional review board (IRB) of Samsung Medical Center (2018-03-110).
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Carcinoma Pulmonar de Células não Pequenas , Carcinoma de Células Escamosas , Neoplasias Pulmonares , Animais , Carcinoma de Células Escamosas/genética , Humanos , Pulmão , Neoplasias Pulmonares/genética , Camundongos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Brachypodium distachyon is an annual C3 grass used as a monocot model system in functional genomics research. Insertional mutagenesis is a powerful tool for both forward and reverse genetics studies. In this study, we explored the possibility of using the tobacco retrotransposon Tnt1 to create a transposon-based insertion mutant population in B. distachyon. We developed transgenic B. distachyon plants expressing Tnt1 (R0) and in the subsequent regenerants (R1) we observed that Tnt1 actively transposed during somatic embryogenesis, generating an average of 6.37 insertions per line in a population of 19 independent R1 regenerant plants analyzed. In seed-derived progeny of R1 plants, Tnt1 segregated in a Mendelian ratio of 3:1 and no new Tnt1 transposition was observed. A total of 126 flanking sequence tags (FSTs) were recovered from the analyzed R0 and R1 lines. Analysis of the FSTs showed a uniform pattern of insertion in all the chromosomes (1-5) without any preference for a particular chromosome region. Considering the average length of a gene transcript to be 3.37 kb, we estimated that 29 613 lines are required to achieve a 90% possibility of tagging a given gene in the B. distachyon genome using the Tnt1-based mutagenesis approach. Our results show the possibility of using Tnt1 to achieve near-saturation mutagenesis in B. distachyon, which will aid in functional genomics studies of other C3 grasses.
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Brachypodium/genética , Mutagênese Insercional , Proteínas de Plantas/genética , Retroelementos/genética , Cromossomos de Plantas/genética , Mutagênese Insercional/métodos , Proteínas de Plantas/metabolismo , Plantas Geneticamente ModificadasRESUMO
Objectives: Sulforaphane, a major ingredient isolated from Brassica oleracea var. italica (broccoli), is known to exhibit anti-inflammatory, anti-cancer, and anti-diabetic effects. In this study, we employed an in vitro model of phorbol 12-myristate 13-acetate and a23187 (PMACI)-stimulated human mast cells (HMC-1 cells) to investigate the anti-allergic inflammatory effects and mechanisms of sulforaphane and Brassica oleracea var. italica extracts.Methods: Cytokine levels were measured by ELISA and quantitative real-time-PCR methods. Caspase-1 activity was determined by caspase-1 assay. Binding mode of sulforaphane within caspase-1 was determined by molecular docking simulation. Protein expression was determined by Western blotting.Results: Water extract of Brassica oleracea var. italica (WE) significantly reduced thymic stromal lymphopoietin (TSLP) secretion and caspase-1 activity on activated HMC-1 cells. In the molecular docking simulation and in vitro caspase-1 assays, sulforaphane regulated caspase-1 activity by docking with the identical binding site of caspase-1. Sulforaphane significantly inhibited the levels of inflammatory mediators including TSLP, tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-6, and IL-8 in a dose-dependent manner. Immunoblotting experiments revealed that sulforaphane and WE reduced translocation of NF-κBp65 into the nucleus and phosphorylation of IκBα in the cytosol. Furthermore, phosphorylation of mitogen-activated protein kinases (MAPK) was down-regulated by treatment with sulforaphane or WE.Conclusion: Our findings suggest that sulforaphane and WE have anti-allergic inflammatory effects by intercepting caspase-1/NF-κB/MAPKs signaling pathways.
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Antialérgicos/farmacologia , Brassica/química , Isotiocianatos/farmacologia , Mastócitos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Antialérgicos/isolamento & purificação , Caspase 1/metabolismo , Linhagem Celular , Simulação por Computador , Humanos , Interleucinas/metabolismo , Isotiocianatos/isolamento & purificação , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Mastócitos/imunologia , NF-kappa B/metabolismo , Extratos Vegetais/isolamento & purificação , Sulfóxidos , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Legumes play irreplaceable roles in sustainable agriculture due to their unique capability of fixing gaseous nitrogen in the atmosphere and turning into plant-usable ammonium through interaction with rhizobia. With the completion of genome sequencing of several model and non-model legumes, it is highly desirable to generate mutant populations for characterizing gene functions in genome-wide scales. In the past decade, we have generated a near-saturated insertional mutant population in the model legume Medicago truncatula using the tobacco-derived Tnt1 retrotransposon at Noble Research Institute. The mutant population was generated through callus induction, subculture, and regeneration from a starting transgenic line harboring three homozygous copies of Tnt1 insertion. The population consists of 21,700 regenerated lines that encompass more than 500,000 Tnt1 insertions. Based on the genome size, average gene length, and random insertion nature of Tnt1, this mutant population covers about 90% of genes in the M. truncatula genome. Due to the convenience of known Tnt1 sequence, the mutant population is highly feasible for both forward and reverse genetics. Over the past 12 years, we have distributed more than 9000 mutant lines to 203 research groups in 24 countries.
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Medicago truncatula/genética , Mutagênese Insercional , Retroelementos , Genes de Plantas , Genótipo , Desenvolvimento Vegetal , Plantas Geneticamente ModificadasRESUMO
BACKGROUND: Although the draft genome of sorghum is available, the understanding of gene function is limited due to the lack of extensive mutant resources. Virus-induced gene silencing (VIGS) is an alternative to mutant resources to study gene function. This study reports an improved and efficient method for Brome mosaic virus (BMV)-based VIGS in sorghum. METHODS: Sorghum plants were rub-inoculated with sap prepared by grinding 2 g of infected Nicotiana benthamiana leaf in 1 ml 10 mM potassium phosphate buffer (pH 6.8) and 100 mg of carborundum abrasive. The sap was rubbed on two to three top leaves of sorghum. Inoculated plants were covered with a dome to maintain high humidity and kept in the dark for two days at 18 °C. Inoculated plants were then transferred to 18 °C growth chamber with 12 h/12 h light/dark cycle. RESULTS: This study shows that BMV infection rate can be significantly increased in sorghum by incubating plants at 18 °C. A substantial variation in BMV infection rate in sorghum genotypes/varieties was observed and BTx623 was the most susceptible. Ubiquitin (Ubiq) silencing is a better visual marker for VIGS in sorghum compared to other markers such as Magnesium Chelatase subunit H (ChlH) and Phytoene desaturase (PDS). The use of antisense strand of a gene in BMV was found to significantly increase the efficiency and extent of VIGS in sorghum. In situ hybridization experiments showed that the non-uniform silencing in sorghum is due to the uneven spread of the virus. This study further demonstrates that genes could also be silenced in the inflorescence of sorghum. CONCLUSION: In general, sorghum plants are difficult to infect with BMV and therefore recalcitrant to VIGS studies. However, by using BMV as a vector, a BMV susceptible sorghum variety, 18 °C for incubating plants, and antisense strand of the target gene fragment, efficient VIGS can still be achieved in sorghum.
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Bromovirus , Inativação Gênica , Sorghum/genética , Bromovirus/genética , DNA Antissenso/genética , Flores/virologia , Folhas de Planta/virologia , Sorghum/metabolismo , Sorghum/virologia , Temperatura , Ubiquitina/metabolismoRESUMO
Virus-induced gene silencing (VIGS) is an important forward and reverse genetics method for the study of gene function in many plant species, especially Nicotiana benthamiana. However, despite the widespread use of VIGS, a searchable database compiling the phenotypes observed with this method is lacking. Such a database would allow researchers to know the phenotype associated with the silencing of a large number of individual genes without experimentation. We have developed a VIGS phenomics and functional genomics database (VPGD) that has DNA sequence information derived from over 4,000 N. benthamiana VIGS clones along with the associated silencing phenotype for approximately 1,300 genes. The VPGD has a built-in BLAST search feature that provides silencing phenotype information of specific genes. In addition, a keyword-based search function could be used to find a specific phenotype of interest with the corresponding gene, including its Gene Ontology descriptions. Query gene sequences from other plant species that have not been used for VIGS can also be searched for their homologs and silencing phenotype in N. benthamiana. VPGD is useful for identifying gene function not only in N. benthamiana but also in related Solanaceae plants such as tomato and potato. The database is accessible at http://vigs.noble.org.
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Brachypodium distachyon is a model grass species for economically important cereal crops. Efforts are in progress to develop useful functional genomic resources in Brachypodium. A tobacco retrotransposon, Tnt1, has been used successfully in recent past to generate insertional mutagenesis in several dicot plant species. Tnt1 retrotransposon replicates, transposes, and inserts at multiple random genomic locations in the plant genome. Transposition occurs only during somatic embryogenesis but not during seed transmission. We developed Brachypodium transgenic plants that can express the Tnt1 element. Here, we describe an efficient tissue culture-based approach to generate Tnt1 insertional mutant population using transgenic Brachypodium line expressing the Tnt1 retrotransposon.
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Brachypodium/genética , Mutagênese Insercional/métodos , Plantas Geneticamente Modificadas/genética , Retroelementos , Técnicas de Cultura de Tecidos/métodos , Brachypodium/embriologia , Brachypodium/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/embriologia , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Sementes/embriologia , Sementes/genética , Sementes/crescimento & desenvolvimento , Nicotiana/genéticaRESUMO
Plants have complex and adaptive innate immune responses against pathogen infections. Stomata are key entry points for many plant pathogens. Both pathogens and plants regulate stomatal aperture for pathogen entry and defense, respectively. Not all plant proteins involved in stomatal aperture regulation have been identified. Here, we report GENERAL CONTROL NONREPRESSIBLE4 (GCN4), an AAA+-ATPase family protein, as one of the key proteins regulating stomatal aperture during biotic and abiotic stress. Silencing of GCN4 in Nicotiana benthamiana and Arabidopsis thaliana compromises host and nonhost disease resistance due to open stomata during pathogen infection. AtGCN4 overexpression plants have reduced H+-ATPase activity, stomata that are less responsive to pathogen virulence factors such as coronatine (phytotoxin produced by the bacterium Pseudomonas syringae) or fusicoccin (a fungal toxin produced by the fungus Fusicoccum amygdali), reduced pathogen entry, and enhanced drought tolerance. This study also demonstrates that AtGCN4 interacts with RIN4 and 14-3-3 proteins and suggests that GCN4 degrades RIN4 and 14-3-3 proteins via a proteasome-mediated pathway and thereby reduces the activity of the plasma membrane H+-ATPase complex, thus reducing proton pump activity to close stomata.
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Proteínas 14-3-3/metabolismo , Adaptação Fisiológica , Proteínas de Arabidopsis/metabolismo , Arabidopsis/imunologia , Resistência à Doença , Secas , Nicotiana/imunologia , Estômatos de Plantas/fisiologia , Ácido Abscísico/farmacologia , Adaptação Fisiológica/efeitos dos fármacos , Arabidopsis/microbiologia , Arabidopsis/fisiologia , Membrana Celular/metabolismo , Sequência Conservada , DNA Complementar/genética , Inativação Gênica/efeitos dos fármacos , Modelos Biológicos , Imunidade Vegetal/efeitos dos fármacos , Estômatos de Plantas/efeitos dos fármacos , Plantas Geneticamente Modificadas , Complexo de Endopeptidases do Proteassoma/metabolismo , Ligação Proteica , ATPases Translocadoras de Prótons/metabolismo , Estresse Fisiológico , Nicotiana/efeitos dos fármacos , Nicotiana/fisiologiaRESUMO
BACKGROUND: Evidence consistently shows that diabetes is a risk factor for increased prevalence of gingivitis and periodontitis. But there is a controversy about the relationship between diabetes related factors and periodontal health. The aim of the present study is to explore the relationship between diabetes related factors such as glycosylated hemoglobin, fasting blood glucose, duration of diabetes and compliance to diabetes self management and periodontal health status. METHODS: Periodontal health of 125 participants with type-2 diabetes mellitus was measured by the number of missing teeth, community periodontal index (CPI), Russell's periodontal index and papillary bleeding index. Information on sociodemographic factors, oral hygiene behavior, duration and compliance to self management of diabetes, levels of glycosylated hemoglobin(HbA1c) and fasting blood glucose(FBG) were collected by interview and hospital medical records. Statistically, independent t-test, an analysis of variance (ANOVA), chi-squared test and multiple regression analyses were used to assess the association between diabetes-related factors and periodontal health. RESULTS: Periodontal parameters including the number of missing teeth and papillary bleeding index were significantly influenced by duration of diabetes, FBG and compliance to self management of diabetes. CPI was significantly influenced by duration of diabetes, FBG and HbA1C. And Russell's periodontal index was significantly influenced by duration of diabetes, FBG, HbA1C and compliance to self management of diabetes. Results of multiple linear regression analysis showed that the duration of diabetes showed significant positive correlation with all of the periodontal health parameters, except for missing teeth. HbA1c was correlated with Russell's periodontal and papillary bleeding index. FBG and compliance to self management of diabetes were correlated with missing teeth and papillary bleeding index respectively. CONCLUSIONS: Diabetes-related factors such as duration of diabetes, FBG, HbA1c and compliance to self management of diabetes were significantly correlated with periodontal health among individuals with type-2 diabetes.
Assuntos
Diabetes Mellitus Tipo 2/complicações , Periodontite/complicações , Adulto , Fatores Etários , Idoso , Consumo de Bebidas Alcoólicas , Glicemia/análise , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/prevenção & controle , Escolaridade , Feminino , Hemoglobinas Glicadas/análise , Comportamentos Relacionados com a Saúde , Educação em Saúde Bucal , Humanos , Masculino , Pessoa de Meia-Idade , Saúde Bucal , Higiene Bucal , Cooperação do Paciente , Índice Periodontal , Autocuidado , Autoimagem , Fumar , Fatores de Tempo , Perda de Dente/classificação , Escovação DentáriaRESUMO
Nonhost disease resistance of plants against bacterial pathogens is controlled by complex defense pathways. Understanding this mechanism is important for developing durable disease-resistant plants against wide range of pathogens. Virus-induced gene silencing (VIGS)-based forward genetics screening is a useful approach for identification of plant defense genes imparting nonhost resistance. Tobacco rattle virus (TRV)-based VIGS vector is the most efficient VIGS vector to date and has been efficiently used to silence endogenous target genes in Nicotiana benthamiana. In this manuscript, we demonstrate a forward genetics screening approach for silencing of individual clones from a cDNA library in N. benthamiana and assessing the response of gene silenced plants for compromised nonhost resistance against nonhost pathogens, Pseudomonas syringae pv. tomato T1, P. syringae pv. glycinea, and X. campestris pv. vesicatoria. These bacterial pathogens are engineered to express GFPuv protein and their green fluorescing colonies can be seen by naked eye under UV light in the nonhost pathogen inoculated plants if the silenced target gene is involved in imparting nonhost resistance. This facilitates reliable and faster identification of gene silenced plants susceptible to nonhost pathogens. Further, promising candidate gene information can be known by sequencing the plant gene insert in TRV vector. Here we demonstrate the high throughput capability of VIGS-mediated forward genetics to identify genes involved in nonhost resistance. Approximately, 100 cDNAs can be individually silenced in about two to three weeks and their relevance in nonhost resistance against several nonhost bacterial pathogens can be studied in a week thereafter. In this manuscript, we enumerate the detailed steps involved in this screening. VIGS-mediated forward genetics screening approach can be extended not only to identifying genes involved in nonhost resistance but also to studying genes imparting several biotic and abiotic stress tolerances in various plant species.
Assuntos
Inativação Gênica , Doenças das Plantas/genética , Vírus de Plantas/genética , Plantas/genética , Bactérias/genética , Bactérias/metabolismo , Genes de Plantas , Proteínas de Fluorescência Verde/biossíntese , Proteínas de Fluorescência Verde/genética , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Plantas/imunologia , Nicotiana/genética , Nicotiana/imunologiaRESUMO
Plasmodium vivax malaria is the indigenous strain in the Republic of Korea (ROK). Plasmodium vivax can be transmitted through the transfusions of various blood components, which became a severe problem with the safety of blood transfusions and blood-related products in ROK. We evaluated a P. vivax-specific enzyme-linked immunosorbent assay (Genedia Malaria Ab ELISA 2.0, Green Cross, ROK) with blood samples from four groups: 251 samples from P. vivax-infected patients, 39 samples from post-treatment patients upon follow-up, 200 samples from healthy volunteers and 421 samples from domestic travellers to and from high endemic areas of ROK. The positive cases from the ELISA test were confirmed by both Giemsa microscopic and polymerase chain reaction methods. The clinical sensitivity and specificity of detecting P. vivax with ELISA test were 94.4% and 99.0%, respectively. Thirteen of 421 domestic travellers (3.0%) to endemic areas tested positive. The results indicate the effectiveness of detecting antibodies against P. vivax in blood with Genedia Malaria Ab ELISA 2.0 test in a large blood screen setting.