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Posttraumatic growth (PTG) is a positive psychological change experienced after trauma and it has gained global recognition in recent years. The present study aimed to validate a South Korean version of the Posttraumatic Growth Inventory-Expanded (K-PTGI-X) for use with trauma-exposed and bereaved samples. A national sample comprising South Korean adults was used for the analysis. As a result, the 4-factor bi-factor model was best supported in both the trauma and bereaved groups in terms of personal strength, new possibilities, spiritual-existential change, and being able to relate to others. Additionally, the K-PTGI-X showed satisfying reliability, concurrent validity, and discriminant validity. Lastly, regarding the group differences, women showed higher rates of PTG than men and the bereaved group exhibited higher spiritual and existential growth in the PTG than the trauma group. Given these results, implications for adaptation in various fields when assessing and encouraging PTG in practical settings are discussed.
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Since suicide is one of the major health problems worldwide, the goal of the present study is to develop a psychometrically sound suicide risk screening tool named Suicide Screening Questionnaire- Self-Rating (SSQ-SR) to quantify the risk of suicidal behavior. The development process includes item generation, item revision and refinement, and validation. A total sample of 2,238 adults in South Korea was used for analysis. The results of factor analysis showed that the SSQ-SR, containing 25 items, supported a three-factor model: "Situational factors," "Negative self-perceptions and mental health factors," and "Suicidal thoughts and behaviors." Also, SSQ-SR showed satisfying internal consistency, concurrent validity and discriminant validity. Lastly, the results of ROC analysis showed a cut-off point of 33.5 for the low-risk group and 36.5 for the high-risk group. Considering these results, the current results demonstrate the SSQ-SR is a valid scale and therefore can contribute to future suicide-related studies and prevention.
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The aim of this study was to identify the outcomes of parental bereavement and the changes in life experience that follow the traumatic death of a teenage child. The results of the study are aimed to assist counselors and educators who work with themes of grief and loss. From 17 in-depth interviews from parents bereaved by the Sewol ferry disaster of 2014 in South Korea, three main categories were found to capture the reality for parents after the sudden and traumatic death of a teenage child: (a) personal changes, (b) changes in close relationships, and (c) changes in social life. Recommendations for future research and potential implications were discussed.
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Luto , Desastres , Acontecimentos que Mudam a Vida , Pais/psicologia , Adolescente , Adulto , Feminino , Humanos , Entrevistas como Assunto , Masculino , República da Coreia , Estudos RetrospectivosRESUMO
In this study, 3,4,5-trisubstituted piperidines were synthesized enantioselectively, and their antioxidant activity was evaluated. The 3,4,5-trisubstituted piperidines containing TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl) and a spatially proximal hydroxy group showed good antioxidant activity. Some of these compounds showed IC50 values in a nanomolar range, comparable to that of TEMPO. Probably the TEMPO generated from the homolysis of the CON bond of 3,4,5-trisubstituted piperidines functions as a radical-scavenging entity, and the hydroxy group of piperidines has a synergistic effect to the antioxidant activity.
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Antioxidantes/farmacologia , Piperidinas/farmacologia , Antioxidantes/síntese química , Antioxidantes/química , Relação Dose-Resposta a Droga , Estrutura Molecular , Piperidinas/síntese química , Piperidinas/química , Estereoisomerismo , Relação Estrutura-AtividadeRESUMO
Despite the fact that a large number of miRNA sequences have been determined in diverse plant species, reports demonstrating the functional roles of miRNAs in the plant response to pathogens are severely limited. Here, Arabidopsis thaliana miRNA844 (miR844) was investigated for its functional role in the defense response to diverse pathogens. Transgenic Arabidopsis plants overexpressing miR844 (35S::miR844) displayed much more severe disease symptoms than the wild-type plants when challenged with the bacterium Pseudomonas syringae pv. tomato DC3000 or the fungus Botrytis cinerea. By contrast, a loss-of-function mir844 mutant showed an enhanced resistance against the pathogens. Although no cleavage was observed at the predicted cleavage site of the putative target mRNA, cytidinephosphate diacylglycerol synthase3 (CDS3), cleavage was observed at 6, 12, 21, or 52 bases upstream of the predicted cleavage site of CDS3 mRNA, and the level of CDS3 mRNA was downregulated by the overexpression of miR844, implying that miR844 influences CDS3 transcript level. To further confirm that the miR844-mediated defense response was due to the decrease in CDS3 mRNA level, the disease response of a CDS3 loss-of-function mutant was analyzed upon pathogen challenge. Increased susceptibility of both cds3 mutant and 35S::miR844 plants to pathogens confirmed that miR844 affected the defense response by downregulating CDS3 mRNA. The expression of miR844 was decreased, and the CDS3 transcript level increased upon pathogen challenge. Taken together, these results provide evidence that downregulation of miR844 and a concomitant increase in CDS3 expression is a defensive response of Arabidopsis to bacteria and fungi.
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Proteínas de Arabidopsis/genética , Arabidopsis/genética , Arabidopsis/microbiologia , MicroRNAs/genética , Proteínas de Arabidopsis/metabolismo , Botrytis/patogenicidade , Regulação da Expressão Gênica de Plantas , Interações Hospedeiro-Patógeno/genética , Plantas Geneticamente Modificadas , Pseudomonas syringae/patogenicidadeRESUMO
Although a large number of microRNAs (miRNAs) have been identified in different plant species, the functional roles and targets of the majority of miRNAs have not yet been determined. Here, Arabidopsis thaliana miRNA400 (miR400) was investigated for its functional role in the defense response to diverse pathogens. Transgenic Arabidopsis plants that overexpress MIR400 (35S::MIR400) displayed much more severe disease symptoms than the wild-type plants when infected with the bacterium Pseudomonas syringae pv. tomato DC3000 or the fungus Botrytis cinerea. MiR400 guided the cleavage of two genes (At1g06580 and At1g62720) encoding pentatricopeptide repeat (PPR) proteins. To confirm further that the miR400-mediated defense response was due to the cleavage of PPR mRNAs, loss-of-function mutant and artificial miRNA-mediated knockdown mutants of PPR were generated, and their disease responses were analyzed upon pathogen challenge. Similar to the 35S::MIR400 plants, the ppr mutants displayed much more severe disease symptoms than the wild-type plants when challenged with the pathogens, indicating that miR400 affects the defense response by cleaving PPR mRNAs. Expression of miR400 was down-regulated, whereas the PPR1 and PPR2 transcripts increased upon pathogen challenge. Collectively, the present study reveals that miR400-mediated dysfunction of PPR proteins renders Arabidopsis more susceptible to pathogenic bacteria and fungi, which emphasizes the importance of PPR proteins in plant defense against diverse pathogens.
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Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Suscetibilidade a Doenças , Regulação da Expressão Gênica de Plantas , MicroRNAs/metabolismo , Doenças das Plantas/imunologia , Arabidopsis/imunologia , Arabidopsis/fisiologia , Proteínas de Arabidopsis/genética , Botrytis/fisiologia , Técnicas de Silenciamento de Genes , Germinação , Temperatura Alta , MicroRNAs/genética , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Mutação , Fenótipo , Folhas de Planta/genética , Folhas de Planta/imunologia , Folhas de Planta/fisiologia , Plantas Geneticamente Modificadas , Pseudomonas syringae/fisiologia , RNA Mensageiro/genética , RNA de Plantas/genética , Plântula/genética , Plântula/imunologia , Plântula/fisiologia , Sementes/genética , Sementes/imunologia , Sementes/fisiologiaRESUMO
BACKGROUND: Although several chloroplast RNA splicing and ribosome maturation (CRM) domain-containing proteins have been characterized for intron splicing and rRNA processing during chloroplast gene expression, the functional role of a majority of CRM domain proteins in plant growth and development as well as chloroplast RNA metabolism remains largely unknown. Here, we characterized the developmental and stress response roles of a nuclear-encoded chloroplast protein harboring a single CRM domain (At4g39040), designated CFM4, in Arabidopsis thaliana. RESULTS: Analysis of CFM4-GFP fusion proteins revealed that CFM4 is localized to chloroplasts. The loss-of-function T-DNA insertion mutants for CFM4 (cfm4) displayed retarded growth and delayed senescence, suggesting that CFM4 plays a role in growth and development of plants under normal growth conditions. In addition, cfm4 mutants showed retarded seed germination and seedling growth under stress conditions. No alteration in the splicing patterns of intron-containing chloroplast genes was observed in the mutant plants, but the processing of 16S and 4.5S rRNAs was abnormal in the mutant plants. Importantly, CFM4 was determined to possess RNA chaperone activity. CONCLUSIONS: These results suggest that the chloroplast-targeted CFM4, one of two Arabidopsis genes encoding a single CRM domain-containing protein, harbors RNA chaperone activity and plays a role in the Arabidopsis growth and stress response by affecting rRNA processing in chloroplasts.
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Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/fisiologia , Núcleo Celular/metabolismo , Proteínas de Cloroplastos/metabolismo , Estresse Fisiológico , Sequência de Aminoácidos , Proteínas de Cloroplastos/química , Cloroplastos/genética , Teste de Complementação Genética , Chaperonas Moleculares/metabolismo , Dados de Sequência Molecular , Mutação/genética , Fenótipo , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas , Estrutura Terciária de Proteína , Processamento Pós-Transcricional do RNA/genética , Splicing de RNA/genética , RNA de Cloroplastos/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Ribossômico/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Alinhamento de Sequência , Relação Estrutura-AtividadeRESUMO
Brown rot disease, caused by Monilinia spp., poses a significant threat to pome and stone fruit crops globally, resulting in substantial economic losses during pre- and post-harvest stages. Monilinia fructigena, M. laxa, and M. fructicola are identified as the key agents responsible for brown rot disease. In this study, we employed the amplified fragment length polymorphism (AFLP) method to assess the genetic diversity of 86 strains of Monilinia spp. isolated from major stone fruit cultivation regions in South Korea. Specifically, strains were collected from Chungcheong, Gangwon, Gyeonggi, Gyeongsang, and Jeolla provinces (-do). A comparative analysis of strain characteristics, such as isolation locations, host plants, and responses to chemical fungicides, was conducted. AFLP phylogenetic classification using 20 primer pairs revealed the presence of three distinct groups, with strains from Jeolla province consistently forming a separate group at a high frequency. Furthermore, M. fructicola was divided into three groups by the AFLP pattern. Principal coordinate analysis and PERMANOVA were applied to compare strain information, such as origin, host, and fungicide sensitivity, revealing significant partition patterns for AFLP according to geographic origin and host plants. This study represents the utilization of AFLP methodology to investigate the genetic variability among M. fructicol isolates, highlighting the importance of continuous monitoring and management of variations in the brown rot pathogen.
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In this study, the quality characteristics of scones containing 0, 2, 4, 6, and 8% Pinus koraiensis (Korean pine) leaf powder were analyzed. P. koraiensis is a plant belonging to the pine family and the leaf of P. koraiensis are known to have various effects, including antioxidant functions. The specific gravity, baking loss, moisture content, pH, chromaticity, texture, and antioxidant activity of the scones were measured. The results showed that, with the concentration of P. koraiensis leaf powder (PKLP) increased, the scones showed a significant decrease (P<0.001) in specific gravity. Regarding chromaticity, the brightness decreased significantly (P<0.001), and there was a significant increase (P<0.001) in redness after the addition of PKLP. We also found that the hardness of the scones was significantly decreased (P=0.001) with the addition of leaf powder. Regarding the antioxidant activity, the contents of polyphenols (P=0.007), flavonoids (P<0.001), and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (P<0.001) were all significantly increased with the addition of the leaf powder. This study provides potential for the development of various foods using P. koraiensis leaf.
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Herein, we explored the potential of the apple's core microbiota for biological control of Erwinia amylovora, which causes fire blight disease, and analyzed the structure of the apple's bacterial community across different tissues and seasons. Network analysis results showed distinct differences in bacterial community composition between the endosphere and rhizosphere of healthy apples, and eight taxa were identified as negatively correlated with E. amylovora, indicating their potential key role in a new control strategy against the pathogen. This study highlights the critical role of the apple's bacterial community in disease control and provides a new direction for future research in apple production. In addition, the findings suggest that using the composition of the apple's core taxa as a biological control strategy could be an effective alternative to traditional chemical control methods, which have been proven futile and environmentally harmful.
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Erwinia amylovora , Malus , Malus/microbiologia , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia , Estações do AnoRESUMO
OBJECTIVES: The landscape of early-stage endometrial cancer treatment has changed dramatically over the last decade. The aim of this study is to provide a real-world view of the impact sentinel lymph node (SLN) biopsy has had on both clinical practice and patient outcomes. We describe detection and recurrence rates, as well as our experience in managing low volume lymph node disease. METHODS: We conducted an international, multicenter retrospective cohort study of 1012 patients with apparent early-stage endometrial cancer. Eligible patients underwent primary surgical staging and SLN biopsy in one of three large academic tertiary cancer centers in Canada or the Republic of Korea between 2015 and 2019. Demographic, surgical, clinicopathologic and recurrence data were collected through chart review. RESULTS: A total of 1012 patients were included. Overall SLN detection rate for all tracer types was 94.1% and recurrence rate was 5.3%. Higher FIGO stage (III vs. I/II) was associated with failed bilateral mapping (OR 2.27, 95%CI 1.14-4.52). We identified seven patients with micrometastases and 12 with isolated tumor cells, of which only one patient with micrometastases recurred at 17 months. Recurrence rates based on risk groups were 2.1%, 5.3%, 8.1%, and 9.9% for low, intermediate, high-intermediate, and high risk, respectively. CONCLUSION: SLN biopsy is safe and feasible. Detection rates are high, regardless of which tracer type is used and recurrence rates are low, especially in low and intermediate risk disease. Patients with low volume metastases appear to have low risk of recurrence, but replication of our findings by large prospective studies are needed to elucidate their clinical importance.
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Neoplasias do Endométrio , Linfonodo Sentinela , Feminino , Humanos , Biópsia de Linfonodo Sentinela , Linfonodos/patologia , Estudos Retrospectivos , Micrometástase de Neoplasia/patologia , Excisão de Linfonodo , Neoplasias do Endométrio/cirurgia , Neoplasias do Endométrio/patologia , Estadiamento de Neoplasias , Linfonodo Sentinela/cirurgia , Linfonodo Sentinela/patologiaRESUMO
The threat of COVID-19 outbreak in South Korea and around the globe challenged not only physical health but also mental health, increasing the chances of disorders such as posttraumatic stress disorder (PTSD). Such pandemic situation can be referred to a traumatic event for citizens. The present study aims to examine the psychometric properties of the PTSD Checklist (PCL-5), which is named the K-COVID-related-PTSD. The scale measures PTSD symptomology in the context of the COVID-19 pandemic in South Korea. A total of 1434 South Korean citizens were included in this study. The data were statistically analyzed using SPSS 21.0 and Mplus 8.0. The results of confirmatory factor analysis demonstrated a superior fit for the seven-factor hybrid model (x2 = 1425.445 (df = 149), CFI = 0.950, TLI = 0.937, SRMR = 0.033, RMSEA = 0.077) consisting of re-experiencing, negative affect, anxious arousal, dysphoric arousal, avoidance, anhedonia, and externalizing behaviors. Furthermore, the K-COVID-related-PTSD showed a satisfactory level of internal consistency (α = 0.793 to α = 0.939) with good convergent and discriminant validity. Finally, concurrent validity was confirmed by the significant correlations with all the negative mental health outcomes, such as PTSD symptoms, somatization, depression, anxiety, anger, negative affect, job burnout, and suicidal ideation. Overall, the current results demonstrate the K-COVID-related-PTSD is a valid scale and therefore has important implications for future pandemic-related studies.
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COVID-19 , Transtornos de Estresse Pós-Traumáticos , COVID-19/epidemiologia , Análise Fatorial , Humanos , Pandemias , República da Coreia/epidemiologia , Transtornos de Estresse Pós-Traumáticos/psicologiaRESUMO
Background: Observer rating scales are necessary to evaluate the risk of suicide because individuals at risk for suicide are often unwilling to seek help on their own. Reliability and validity were evaluated for the newly developed Suicide Screening Questionnaire-Observer Rating (SSQ-OR). Methods: Preliminary items were assessed by 251 experts online and 25 questions were selected. 328 individuals at high-risk and 661 controls from 12 Crisis Response Centers and 5 university counseling centers were recruited to complete SSQ-OR, Beck Scale for Suicide Ideation (BSSI) and Patient Health Questionnaire-9 (PHQ-9). In a 6 months follow-up, we reached out to 176 participants to ask whether they had experienced a suicidal thought, plan, or attempt since the baseline assessment. Cronbach's α, Mann-Whitney U test, Spearman's correlation, factor analyses, Receiver operating characteristic (ROC) analysis and logistic regression analysis were used to verify the SSQ-OR. Results: Structural validity was supported by a two-factor solution using exploratory and confirmatory factor analyses. Excellent model fit indices for the two-factor structure using exploratory factor analysis were confirmed (RMSEA = 0.033, TLI = 0.980, CFI = 0.983). The SSQ-OR demonstrated strong internal consistency. The concurrent validity based on the correlations with other self-reported indicators of suicidal potential-BSSI and PHQ-9- revealed substantial relationships. The high-risk group was effectively characterized by a cut-off point of 4, with a sensitivity of 0.73 and a specificity of 0.79. The SSQ-OR scores were significant predictors of suicidal thoughts and behaviors within 6 months. Conclusions: The SSQ-OR exhibits sound psychometric properties, and could be used as a complement to a self-report or clinical-administered scale to screen suicide risk comprehensively.
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(1) Objective: To investigate the factors that affect rates of neutralizing antibody production and duration after vaccination using the newly developed SARS-CoV-2 POCT. (2) Methods: The production of immunoglobulin and neutralizing antibody in clinical subjects who completed various vaccines was analyzed using the POCT, the semi-quantitative was interpreted by measurement application, and the quantified neutralizing antibody titers were using the ELISA. (3) Results: According to the clinical performance analysis of the POCT, the clinical sensitivity and the specificity were 96.8% (90/93) and 97.7% (167/171), respectively, for the S1 RBD IgG antibody. The clinical sensitivity was 92.22% (83/90), and the clinical specificity was 100.00% (174/174) for neutralizing antibodies. Factors influencing antibody production were analyzed using the whole blood of the five types of second-completed vaccinators (N = 736, 20−80 years old). General and neutralizing antibody and showed significant differences in age (p < 0.0001), vaccine type (p < 0.0001), inoculation interval (p < 0.0001), pain score (p < 0.0001), diabetes (p < 0.0001), and hypertension (p = 0.002). The gender (p = 0.021) and chronic fatigue (p = 0.02) did not show the significance. (4) Conclusions: An acquisition of immunoglobulin and neutralizing antibody varies according to vaccine type, age, days after vaccination, pain degree after vaccination, and underlying diseases. The POCT used in this study will be utilized for clinical recommendations such as deciding whether to receive additional vaccines through the immediate rapid determination of neutralizing antibody generation in the clinical site.
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Intra-uterine growth retardation has been linked to the development of type 2 diabetes in later life. Mitochondrial changes have been suggested as a link between fetal malnutrition and adult insulin resistance. Taurine has been implicated in this process. We investigated whether protein malnutrition in early life alters mitochondria of the pancreatic islets in adulthood, and whether taurine supplementation restores these changes. Male offspring of rats fed a control diet, a low-protein diet or a low-protein diet supplemented with taurine during pregnancy and lactation were weaned onto the control diet. In each group, at 20 weeks of age, intravenous glucose tolerance tests, euglycaemic-hyperinsulinaemic clamp studies, morphometric analysis of the pancreatic islets and ultra-structural analysis of the mitochondria of the ß-cells were performed. The expressions of cytochrome c oxidase (COX) I and mitochondrial respiratory chain complex II were also measured. Fetal protein-malnourished rats showed decreased pancreatic islet mass and reduced insulin-secretory responses to a glucose load. These rats also showed reduced mitochondrial DNA-encoded COX I gene expression in the islets. Electron microscopic examination showed abnormal mitochondrial shapes in the ß-cells of fetal protein-malnourished rats. Taurine supplementation to the low-protein diet restored all these changes. Our findings indicate that a maternal protein-restriction diet causes long-lasting mitochondrial changes that may contribute to the development of type 2 diabetes later in life. The lack of taurine may be a key causative factor for these dysfunctional mitochondrial changes.
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Suplementos Nutricionais , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/metabolismo , Deficiência de Proteína/dietoterapia , Deficiência de Proteína/metabolismo , Taurina/administração & dosagem , Animais , Complexo II de Transporte de Elétrons/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Feminino , Feto/efeitos dos fármacos , Feto/metabolismo , Técnica Clamp de Glucose , Teste de Tolerância a Glucose , Ilhotas Pancreáticas/ultraestrutura , Masculino , Microscopia Eletrônica de Transmissão , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Ratos , Ratos Wistar , Fatores de Transcrição/metabolismoRESUMO
We have previously reported that daptomycin (DAP), a last resort antibiotic, binds to ribosomal protein S19 (RPS19) in humans and exhibits selective anti-cancer activity against MCF7 breast cancer cells. Here, we investigated the role of RPS19 in the anti-cancer effects of DAP and have found that DAP does not induce autophagy, apoptosis or cell viability but does reduce cell proliferation. Our results suggest that an extraribosomal function of RPS19 involves the regulation of vascular endothelial growth factor (VEGF) but not EGF, PDGF or FGF. Engagement of RPS19 by DAP was shown by CETSA and ITDRFCETSA assays, and knocking down of RPS19 with siRNA increased the potency of DAP in MCF7 cells. In addition, DAP suppressed the secretion of VEGF in cancer cells and thereby inhibited cell migration. Collectively, these data provide an outline of the underlying mechanism of how DAP exhibits anti-cancer activity and suggests that RPS19 could be a promising target for the development of new anticancer drugs.
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Antibacterianos/farmacologia , Movimento Celular/efeitos dos fármacos , Daptomicina/farmacologia , Neovascularização Patológica/tratamento farmacológico , Proteínas Ribossômicas/metabolismo , Antibacterianos/química , Antibacterianos/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Daptomicina/química , Daptomicina/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana , Humanos , Estrutura Molecular , Ligação Proteica , Proteínas Ribossômicas/genéticaRESUMO
The functional roles of miR402 in Arabidopsis thaliana were investigated under abiotic stress conditions. Overexpression of miR402 accelerated the seed germination and seedling growth of Arabidopsis under salt stress conditions, while its overexpression promoted only seed germination but not seedling growth of Arabidopsis under dehydration or cold stress conditions. The expression of DEMETER-LIKE protein3 mRNA was down-regulated in miR402-overexpressing transgenic plants. These results imply that miR402 plays a role as a positive regulator of seed germination and seedling growth of Arabidopsis under stress conditions, and that microRNA-guided regulation of DNA demethylation is an adaptive process of plants to stress conditions.
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Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , DNA Glicosilases/metabolismo , Germinação/genética , MicroRNAs/metabolismo , RNA de Plantas/metabolismo , Sementes/crescimento & desenvolvimento , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Temperatura Baixa , DNA Glicosilases/genética , Desidratação , Regulação da Expressão Gênica de Plantas , MicroRNAs/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , RNA Mensageiro/metabolismo , Plântula/genética , Plântula/crescimento & desenvolvimento , Sementes/genética , Cloreto de Sódio/farmacologia , Estresse FisiológicoRESUMO
The Arabidopsis genome encodes six members of microRNA395 (miR395) family previously determined to regulate the expression of ATP sulfurylase (APS) and the sulfate transporter SULTR2;1. However, the mRNA targets for the individual miR395 family members and the biological consequences produced by target gene regulation of each miR395 remain to be identified. In this study, a transgenic approach was employed to determine the mRNA targets for each miR395 family member as well as the role each member plays in plant growth under abiotic stress conditions. Overexpression of miR395c or miR395e retarded and accelerated, respectively, the seed germination of Arabidopsis under high salt or dehydration stress conditions. Despite a single nucleotide difference between miR395c and miR395e, the cleavage of mRNA targets, APS1, APS3, APS4 and SULTR2;1, was not same in miR395c- and miR395e-overexpressing plants. These results demonstrate that a given miRNA family containing a single nucleotide difference can guide the cleavage of various mRNA targets, thereby acting as a positive or negative regulator of seed germination under stress.
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Arabidopsis/fisiologia , Germinação , MicroRNAs/genética , Sementes/fisiologia , Estresse Fisiológico , Arabidopsis/genética , Sequência de Bases , Primers do DNARESUMO
Despite the fact that glycine-rich RNA-binding proteins (GRPs) have been implicated in the responses of plants to environmental stresses, their physiological functions and mechanisms of action in stress responses remain largely unknown. Here, we assessed the functional roles of GRP7, one of the eight GRP family members in Arabidopsis thaliana, on seed germination, seedling growth, and stress tolerance under high salinity, drought, or cold stress conditions. The transgenic Arabidopsis plants overexpressing GRP7 under the control of the cauliflower mosaic virus 35S promoter displayed retarded germination and poorer seedling growth compared with the wild-type plants and T-DNA insertional mutant lines under high salinity or dehydration stress conditions. By contrast, GRP7 overexpression conferred freezing tolerance in Arabidopsis plants. GRP7 is expressed abundantly in the guard cells, and has been shown to influence the opening and closing of the stomata, in accordance with the prevailing stress conditions. GRP7 is localized to both the nucleus and the cytoplasm, and is involved in the export of mRNAs from the nucleus to the cytoplasm under cold stress conditions. Collectively, these results provide compelling evidence that GRP7 affects the growth and stress tolerance of Arabidopsis plants under high salt and dehydration stress conditions, and also confers freezing tolerance, particularly via the regulation of stomatal opening and closing in the guard cells.
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Proteínas de Arabidopsis/fisiologia , Arabidopsis/fisiologia , Estômatos de Plantas/fisiologia , Proteínas de Ligação a RNA/fisiologia , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/análise , Proteínas de Arabidopsis/genética , Núcleo Celular/química , Núcleo Celular/metabolismo , Citoplasma/química , Citoplasma/metabolismo , Congelamento , Germinação/genética , Mutagênese Insercional , Plantas Geneticamente Modificadas/fisiologia , Poli A/metabolismo , Transporte de RNA/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/análise , Proteínas de Ligação a RNA/genética , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Cloreto de Sódio/metabolismo , Água/metabolismoRESUMO
Indoleamine 2,3-dioxygenase (IDO), a key enzyme that catalyses the initial and rate-limiting step in the degradation of the tryptophan, is simultaneously expressed in murine dendritic cells and macrophages stimulated with interferon-gamma (IFN-gamma). In the present study, we investigated whether rosmarinic acid (RA), which is suggested to exhibit anti-oxidant and anti-cyclooxygenase properties, could suppress the functional expression of IDO in murine bone marrow-derived dendritic cells (BMDCs) stimulated with IFN-gamma. Treatment with RA reduced intracellular expression of IDO both in IFN-gamma-activated BMDCs in vitro and in CD11c(+)CD8alpha(+) DCs in vivo tumor-bearing mice model. Consequently, we obtained evidence that RA suppresses the functional activity of IDO and blocks the IDO-dependent T cell suppression. In IFN-gamma-mediated induction of IDO transcription, activation of the signal transducer and activator of transcription 1 (STAT1) is important to be express IDO in IFN-gamma-stimulated BMDCs. In this study, we demonstrated that the RA could also suppress IFN-gamma-induced STAT1 activation. These novel findings provide a new insight into that RA as a pharmacological and transcriptional inhibitor of IDO is worthy of clinical application as well as further investigation for IDO regulation.