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Banana is one of the most important fruits in the world due to its status as a major food source for more than 400 million people. Fusarium oxysporum f. sp. cubense tropical race 4 (Foc TR4) causes substantial losses of banana crops every year, and molecular host resistance mechanisms are currently unknown. We here performed a genomewide analysis of the autophagy-related protein 8 (ATG8) family in a wild banana species. The banana genome was found to contain 10 MaATG8 genes. Four MaATG8s formed a gene cluster in the distal part of chromosome 4. Phylogenetic analysis of ATG8 families in banana, Arabidopsis thaliana, citrus, rice, and ginger revealed five major phylogenetic clades shared by all of these plant species, demonstrating evolutionary conservation of the MaATG8 families. The transcriptomic analysis of plants infected with Foc TR4 showed that nine of the MaATG8 genes were more highly induced in resistant cultivars than in susceptible cultivars. Finally, MaATG8F was found to interact with MaATG4B in vitro (with yeast two-hybrid assays), and MaATG8F and MaATG4B all positively regulated banana resistance to Foc TR4. Our study provides novel insights into the structure, distribution, evolution, and expression of the MaATG8 family in bananas. Furthermore, the discovery of interactions between MaATG8F and MaATG4B could facilitate future research of disease resistance genes for the genetic improvement of bananas.
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BACKGROUND: There is heterogeneity in depressive symptoms. However, latent classes of depressive symptoms and the transition and influences of these in young and middle-aged stroke patients are unclear. OBJECTIVES: The aim of this study was to identify the latent classes of depressive symptoms and their transition patterns over time and the influencing factors in young and middle-aged stroke patients from stabilization to 6 months after discharge. METHODS: This is a longitudinal study following the Strengthening the Reporting of Observational Studies in Epidemiology checklist. A total of 272 young and middle-aged stroke participants were recruited from a hospital neurology ward in Henan Province, China. Participants completed a questionnaire on sociodemographic and health information. Latent transition analysis was used to evaluate the transition pattern of latent classes from stabilization to 6 months after discharge and its influencing factors. RESULTS: One hundred seventy-nine participants were included in the analysis. Three latent classes of depressive symptoms were identified as "mild symptoms," "grief-sleep-fatigue symptoms," and "severe symptoms." Most participants remained in the original latent class from stabilization to 6 months after discharge (probability of 83.8%, 83.8%, and 88.8%). From 3 to 6 months after discharge, the participants with fewer complications were more likely to transition into the mild symptom class. DISCUSSION: The findings indicate that from stabilization to 6 months after discharge, depressive symptoms in young and middle-aged stroke patients in China transitioned gradually from the severe symptom class to the mild symptom. Patients with fewer numbers of poststroke complications were more likely to transition to the mild symptoms class. Future research should focus on depressive symptoms in early-stage stroke patients and provide sufficient psychological support to patients with a high number of complications.
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Depressão , Acidente Vascular Cerebral , Humanos , Pessoa de Meia-Idade , Depressão/epidemiologia , Depressão/etiologia , Depressão/psicologia , Pesar , Estudos Longitudinais , Pacientes , Acidente Vascular Cerebral/complicaçõesRESUMO
BACKGROUND: Schistosomiasis is a serious but neglected parasitic disease in humans that may lead to liver fibrosis and death. Activated hepatic stellate cells (HSCs) are the principal effectors that promote the accumulation of extracellular matrix (ECM) proteins during hepatic fibrosis. Aberrant microRNA-29 expression is involved in the development of fibrotic diseases. However, less is known about the role of miR-29 in Schistosoma japonicum (S. japonicum)-induced hepatic fibrosis. METHODS: The levels of microRNA-29a-3p (miR-29a-3p) and Roundabout homolog 1 (Robo1) were examined in liver tissues during S. japonicum infection. The possible involvement of the miR-29a-3p-Robo1 signaling pathway was determined. We used MIR29A conditional knock-in mice and mice injected with an miR-29a-3p agomir to investigate the role of miR-29a-3p in schistosomiasis-induced hepatic fibrosis. The functional contributions of miR-29a-3p-Robo1 signaling in liver fibrosis and HSC activation were investigated using primary mouse HSCs and the human HSC cell line LX-2. RESULTS: MiR-29a-3p was downregulated in humans and mice with schistosome-induced fibrosis, and Robo1 was upregulated in liver tissues. The miR-29a-3p targeted Robo1 and negatively regulated its expression. Additionally, the expression level of miR-29a-3p in schistosomiasis patients was highly correlated with the portal vein and spleen thickness diameter, which represent the severity of fibrosis. Furthermore, we demonstrated that efficient and sustained elevation of miR-29a-3p reversed schistosome-induced hepatic fibrosis. Notably, we showed that miR-29a-3p targeted Robo1 in HSCs to prevent the activation of HSCs during infection. CONCLUSIONS: Our results provide experimental and clinical evidence that the miR-29a-3p-Robo1 signaling pathway in HSCs plays an important role in the development of hepatic fibrosis. Therefore, our study highlights the potential of miR-29a-3p as a therapeutic intervention for schistosomiasis and other fibrotic diseases.
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MicroRNAs , Schistosoma japonicum , Esquistossomose , Humanos , Camundongos , Animais , Schistosoma japonicum/genética , Schistosoma japonicum/metabolismo , Células Estreladas do Fígado/metabolismo , Proteínas do Tecido Nervoso , MicroRNAs/genética , MicroRNAs/metabolismo , Receptores Imunológicos , Cirrose Hepática/genética , Cirrose Hepática/prevenção & controle , Esquistossomose/patologiaRESUMO
Tissue culture techniques have been routinely used for banana propagation and offered rapid production of planting materials with favorable genotypes and free of pathogenic microorganisms in the banana industry. Meanwhile, extensive scientific work suggests that micropropagated plantlets are more susceptible to Fusarium oxysporum f. sp. cubense (Foc), the deadly strain that causes Fusarium wilt of bananas than conventional planting material due to the loss of indigenous endophytes. In this study, an endophytic bacterium Bacillus velezensis EB1 was isolated and characterized. EB1 shows remarkable in vitro antagonistic activity against Foc with an inhibition rate of 75.43% and induces significant morphological and ultrastructural changes and alterations in the hyphae of Foc. Colony-forming unit (c.f.u.) counting and scanning electron microscopy (SEM) revealed that EB1 could colonize both the surface and inner tissues of banana tissue culture plantlets. Banana tissue culture plantlets of late rooting stage bioprimed with EB1 could efficiently ward off the invasive of Foc. The bio-priming effect could maintain in the acclimatized banana plants and significantly decrease the disease severity of Fusarium wilt and induce strong disease resistance by manipulating plant defense signaling pathways in a pot experiment. Our results provide the adaptability and potential of native endophyte EB1 in protecting plants from pathogens and infer that banana tissue culture plantlets bio-priming with endophytic microbiota could be a promising biological solution in the fight against the Fusarium wilt of banana.
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OBJECTIVE: Little is known about the role of microRNA-29a-3p (miR-29a-3p) in inflammation-related pyroptosis, especially in drug-induced acute liver failure (DIALF). This study aimed to identify the relationship between miR-29a-3p and inflammation-related pyroptosis in DIALF and confirm its underlying mechanisms. METHODS: Thioacetamide (TAA)- and acetaminophen (APAP)-induced ALF mouse models were established, and human samples were collected. The expression levels of miR-29a-3p and inflammation and pyroptosis markers were measured by quantitative real-time polymerase chain reaction (qRT-PCR), Western blotting, or immunochemical staining in miR-29a-3p knock-in transgenic mouse (MIR29A(KI/KI)) DIALF models. In addition, RNA sequencing was conducted to explore the mechanisms. RESULTS: MiR-29a-3p levels were decreased in TAA- and APAP-induced DIALF models. MiR-29a-3p prevented DIALF caused by TAA and APAP. RNA sequencing and further experiments showed that the protective effect of miR-29a-3p on DIALF was mainly achieved through inhibition of inflammation-related pyroptosis, and the inhibition was dependent on activation of the PI3K/AKT pathway. In addition, miR-29a-3p levels were reduced, and pyroptosis was activated in both peripheral blood mononuclear cells and liver tissues of DIALF patients. CONCLUSION: The study supports the idea that miR-29a-3p inhibits pyroptosis by activating the PI3K/AKT pathway to prevent DIALF. MiR-29a-3p may be a promising therapeutic target for DIALF.
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Falência Hepática Aguda , MicroRNAs , Camundongos , Animais , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Piroptose/genética , Proteínas Proto-Oncogênicas c-akt/genética , Acetaminofen/efeitos adversos , Leucócitos Mononucleares/metabolismo , Fosfatidilinositol 3-Quinases , Inflamação/induzido quimicamente , Inflamação/genética , Falência Hepática Aguda/induzido quimicamente , Falência Hepática Aguda/genéticaRESUMO
INTRODUCTION: In recent years, stroke has become more common among young people. Stroke not only has a profound impact on patients' health but also incurs stress and health threats to their caregivers, especially spousal caregivers. Moreover, the health of stroke survivors and their caregivers is interdependent. To our knowledge, no study has explored dyadic health of young and middle-aged stroke survivors and their spousal caregivers from physiological, psychological and social perspectives. Therefore, this proposed study aims to explore the mechanism of how physiological, psychological and social factors affect dyadic health of young and middle-aged stroke survivors and their spousal caregivers. The findings of this study will provide implications for developing interventions to improve dyadic health of this growing population. METHODS AND ANALYSES: We will collect data from 57 dyads of young and middle-aged stroke survivors and their spousal caregivers during hospitalisation and at 1, 3, 6, 9 and 12 months after discharge. Questionnaires will be used to collect participants' demographic information, stress, depression, anxiety, benefit finding, social support, mutuality and quality of life. The following physiological reactions will be collected at baseline, including interleukin 6, tumour necrosis factor-alpha and salivary cortisol. ETHICS AND DISSEMINATION: The study was approved by the ethics review committee of life sciences of Zhengzhou University (No. ZZUIRB2020-53). Prior to being enrolled in the study, participants will be given full and detailed information about the possible risks involved, the informed consent process, confidentiality, the study procedure and secure data storage. Participants will be guaranteed that they can withdraw from the study at any time without providing a reason or leading to any consequences. Both oral and written informed consent will be obtained from all participants. The findings of this proposed study will be disseminated through peer-reviewed journals and academic conferences.
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Cuidadores , Acidente Vascular Cerebral , Pessoa de Meia-Idade , Humanos , Adolescente , Cuidadores/psicologia , Qualidade de Vida/psicologia , Interação Social , Adaptação Psicológica , Acidente Vascular Cerebral/psicologia , Sobreviventes/psicologia , Estudos Observacionais como AssuntoRESUMO
Beneficial interactions between plants and rhizosphere microorganisms are key determinants of plant health with the potential to enhance the sustainability of agricultural practices. However, pinpointing the mechanisms that determine plant disease protection is often difficult due to the complexity of microbial and plant-microbe interactions and their links with the plant's own defense systems. Here, we found that the resistance level of different banana varieties was correlated with the plant's ability to stimulate specific fungal taxa in the rhizosphere that are able to inhibit the Foc TR4 pathogen. These fungal taxa included members of the genera Trichoderma and Penicillium, and their growth was stimulated by plant exudates such as shikimic acid, D-(-)-ribofuranose, and propylene glycol. Furthermore, amending soils with these metabolites enhanced the resistance of a susceptible variety to Foc TR4, with no effect observed for the resistant variety. In total, our findings suggest that the ability to recruit pathogen-suppressive fungal taxa may be an important component in determining the level of pathogen resistance exhibited by plant varieties. This perspective opens up new avenues for improving plant health, in which both plant and associated microbial properties are considered.
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Agricultura , Rizosfera , Solo , Fungos/genética , Raízes de Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia , Microbiologia do SoloRESUMO
Generalized arterial calcification of infancy (GACI) is a rare genetic disease characterized by arterial calcifications or stenoses and hypertension. GACI is caused by mutations in the ENPP1 or ABCC6 genes, and it often causes intrauterine or early infancy death. Here, we report a case of rare GACI caused by a homozygous variation in ENPP1, in a Chinese infant initially presenting with hypertension. The proband was an 8-month-old boy with in utero tricuspid valve calcification, presenting with hypertension at birth. Enhanced computed tomography revealed extensive arterial calcification. Genetic testing identified a homozygous variation in ENPP1 (c.783C > G p.Y261X), which led to the diagnosis of GACI. This mutation has been reported in only three Chinese patients, which all initially presented with hypophosphatemic rickets rather than GACI. This case enriches the clinical and genetic spectrum of ENPP1 mutations and reminds us that GACI should be considered in an infant presenting with hypertension and extensive arterial calcification, and that genetic testing should be performed.
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AIMS AND OBJECTIVES: The aim of this study was to explore the moderated mediation mechanism of the relationships among family function, self-efficacy, care hours per day, closeness and benefit finding in family caregivers of patients with stroke in China. BACKGROUND: Benefit finding can provide a new means of resolving depression among family members caring for an ill loved one. However, current research has paid little attention to the benefit finding of family caregivers of stroke patients in China. DESIGN: A cross-sectional study. METHODS: Three hundred fifty family caregivers of patients with stroke were recruited from community service centres and hospitals in Zhengzhou, China. The participants completed the family APGAR index, caregiver benefit finding scale and Chinese general self-efficacy scale during a study conducted in 2017. Descriptive analyses and a moderated mediation model were computed. Reporting adhered to the STROBE checklist. RESULTS: A total of 311 family caregivers completed this study. Closeness between family caregivers and patients with stroke moderated the relationship between family function and caregiver benefit finding. Self-efficacy partially mediated the relationship between family function and caregiver benefit finding; moreover, care hours per day moderated the mediation. CONCLUSION: This study shows important factors associated with benefit finding in family caregivers of patients with stroke. This indicates elements that could help improve benefit finding intervention programmes for family caregivers of patients with stroke. RELEVANCE TO CLINICAL PRACTICE: The findings in our study provide valuable information on benefit finding and indicate some interventions to improve the mental health of family caregivers of stroke patients.
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Cuidadores , Acidente Vascular Cerebral , Humanos , Cuidadores/psicologia , Autoeficácia , Estudos Transversais , Acidente Vascular Cerebral/terapia , China , FamíliaRESUMO
BACKGROUND: Innovation is essential to advance nursing and health care. However, few studies have focused on innovative behavior of nursing students. OBJECTIVES: The purpose of this study was to explore the mediating effects of creative self-efficacy and achievement motivation on the relationship between clinical practice environment and innovative behavior in Bachelor of Science in Nursing (BSN) students. DESIGN: A descriptive cross-sectional study using an online questionnaire. SETTING: Participants were recruited online from five practice hospitals in Henan Province, China. PARTICIPANTS: A total of 588 BSN students enrolled in the study. METHODS: The participants completed the innovative behavior questionnaire, the clinical practice environment scale, the achievement motivation scale, and the creative self-efficacy scale online in 2022. SPSS PROCESS macro was used for data analysis. The reporting followed the STROBE checklist. RESULTS: A total of 499 valid questionnaires were collected. A positive clinical practice environment was associated with more innovative behavior, and this relation was partially mediated by creative self-efficacy and motive to avoid failure. CONCLUSION: Our study complements the evidence on the mechanism of action between the clinical practice environment and innovative behavior. Our findings have important implications for nursing educators to develop education strategies to inspire nursing students to pursue innovations in school and clinical settings.
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Bacharelado em Enfermagem , Estudantes de Enfermagem , Humanos , Estudos Transversais , Autoeficácia , Docentes de Enfermagem , Motivação , Inquéritos e QuestionáriosRESUMO
INTRODUCTION: The global burden caused by stroke is shifting to young and middle-aged people. Researchers have emphasised the significance of benefit finding (BF) in psychological health. However, current research has paid little attention to stroke and has discussed BF from only a single perspective, that is, that of either patients or caregivers. Our study aims to understand the changing trajectory, predictors and dyadic interaction of BF in dyads of patient who had a stroke and caregiver. METHODS AND ANALYSIS: This study is a longitudinal mixed-methods, multicentre study. A total of 142 patients who had a stroke and 142 spousal caregivers will be investigated. Participants will be recruited from four large public hospitals in northern China. Quantitative and qualitative data will be collected at five time points (near discharge and 1, 3, 6 and 12 months following discharge). Validated and reliable questionnaires will be used in quantitative studies. Information on sociodemographic data, BF, functional status, perceived stress, coping styles and mutuality will be collected from the dyads. Qualitative data will be collected via semistructured interviews and observations. The growth mixture model will be used to analyse quantitative data, and Colaizzi's seven-step analysis method will be used to analyse qualitative data. We plan to conduct parallel but separate quantitative and qualitative data analyses and ultimately integrate the data sets to determine confirmation, expansion or discordance. ETHICS AND DISSEMINATION: All participants will be provided with an informed consent form. This study will encode all identifiable data and store all recorded data on a secure research server. This study has been approved by the Ethics Review Committee of the College of Nursing and Health, Zhengzhou University (ZZUIRB2020-53). The results of the longitudinal study will be published in peer-reviewed journals and presented at national conferences. TRIAL REGISTRATION NUMBER: ChiCTR2000039509.
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Cuidadores , Acidente Vascular Cerebral , Humanos , Pessoa de Meia-Idade , Cuidadores/psicologia , Estudos Longitudinais , Acidente Vascular Cerebral/psicologia , Adaptação Psicológica , China , Qualidade de Vida , Estudos Multicêntricos como AssuntoRESUMO
Abernethy malformation is a rare abnormality of the hepatic portal vein system with non-specific and diverse clinical manifestations. Here, we described a case of abernethy malformation with hepatopulmonary syndrome in a 10-year-old girl. On physical examination, cyanosed lips and acropachy could be found. Her oxygen saturation fluctuated at 89-94%, and the fasting blood ammonia was 98 umol/L. Furthermore, there were abnormalities in the imaging. The microbubble test with contrast echocardiography was positive. Computer tomography angiography (CTA) showed the splenic vein, and the superior mesenteric drained directly into the inferior vena cave after confluence. The same result was also observed in delayed splenic arteriography. Then, we discovered a tiny branch of the intrahepatic portal vein by the inferior vena cava balloon occlusion test, which could also show the confluence of the splenic vein and superior mesenteric vein with the inferior venacave. According to the evidence above, we concluded that the girl was a patient of type II abernethy malformation. For the severe dysplasia of the portal vein, the girl accepted partial ligation of portosystemic shunt and Rex shunt, which improved her oxygen saturation and exercise tolerance.
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ECM33, a glycosylphosphatidylinositol (GPI)-anchored protein, is important for fungal development and infection through regulating fungal cell wall integrity, however, the functions of its orthologs in pathogenesis have not been characterized in Fusarium oxysporum. Here, we discovered a GPI-anchored protein, FocECM33, which is required for vegetative growth and virulence of Fusasium oxysporum f. sp. cubense tropical race 4 (Foc TR4). FocECM33 was highly upregulated during the early infection process of Foc TR4 in banana roots. The targeted disruption of FocECM33 led to decreased hyphal growth, increased sensitivity to cell wall stresses and reduced virulence on banana plantlets. Furthermore, ΔFocECM33 mutant demonstrated a cell morphology defect, elevated ROS production and increased chitin content. Transcriptome analysis showed that FocECM33 has a significant influence on the production of various secondary metabolites and regulation of many biosynthetic processes in Foc TR4. Taken together, it seems FocECM33 contributes to the virulence of Foc TR4 through regulating the process of hyphal growth, ROS production and chitin synthesis.
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Fusarium , Musa , Glicosilfosfatidilinositóis , Musa/microbiologia , Doenças das Plantas/microbiologia , VirulênciaRESUMO
As a typical triazole fungicide, prothioconazole (Pro) has been used extensively due to its broad spectrum and high efficiency. However, as a racemic mixture of two enantiomers (R-Pro and S-Pro), the enantiomer-specific outcomes on the bioactivity have not been fully elucidated. Here, we investigate how chirality affects the activity and mechanism of action of Pro enantiomers on Fusarium oxysporum f. sp. cubense tropical race 4 (Foc TR4), the notorious virulent strain causing Fusarium wilt of banana (FWB). The Pro enantiomers were evaluated in vivo and in vitro with the aid of three bioassay methods for their fungicidal activities against TR4 and the results suggested that the fungicidal activities of Pro enantiomers are stereoselective in a dose-dependent manner with R-Pro making a major contribution to the treatment outcomes. We found that R-Pro led to more severe morphological changes and impairment in membrane integrity than S-Pro. R-Pro also led to the increase of more MDA contents and the reduction of more SOD and CAT activities compared with the control and S-Pro groups. Furthermore, the expression of Cytochrome P450 14α-sterol demethylases (CYP51), the target for triazole fungicides, was significantly increased upon treatment with R-Pro rather than S-Pro, at both transcriptional and translational levels; so were the activities of the Cytochrome P450 enzymes. In addition, surface plasmon resonance (SPR) and molecular docking illuminated the stereoselective interactions between the Pro enantiomers and CYP51 of TR4 at the target site, and R-Pro showed a better binding affinity with CYP51 than S-Pro. These results suggested an enantioselective mechanism of Pro against TR4, which may rely on the enantioselective damages to the fungal cell membrane and the enantiospecific CYP51 binding affinity. Taken together, our study shed some light on the mechanisms underlying the differential activities of the Pro enantiomers against TR4 and demonstrated that Pro can be used as a potential candidate in the treatment of FWB.
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Antifúngicos/farmacologia , Fusarium/efeitos dos fármacos , Estresse Oxidativo , Esterol 14-Desmetilase/genética , Triazóis/farmacologia , Catalase , Regulação Fúngica da Expressão Gênica , Isomerismo , Simulação de Acoplamento Molecular , Esterol 14-Desmetilase/efeitos dos fármacos , Superóxido Dismutase , Triazóis/químicaRESUMO
Background: Mitochondrial intermediate peptidase, encoded by the MIPEP gene, is involved in the processing of precursor mitochondrial proteins related to oxidative phosphorylation. Only a few studies have shown that mutations in MIPEP can cause combined oxidative phosphorylation deficiency-31 (COXPD31), an autosomal recessive multisystem disorder associated with mitochondrial dysfunction. We report herein a rare case of an 8-month-old boy in China with hypertrophic cardiomyopathy (HCM), severe lactic acidosis, and hypotonia caused by novel MIPEP compound heterozygous variants. Methods: Trio-whole-exome sequencing and copy number variation sequencing were performed to identify mutated genetic loci. Sanger sequencing and quantitative real-time PCR were used to validate the candidate single nucleotide variants and copy number variants, respectively. Results: The proband was an 8-month-old boy with HCM, severe lactic acidosis, and hypotonia who died 2 months after his first admission. Two novel compound heterozygous variants, c.1081T > A (p. Tyr361Asn) and a whole deletion (Ex1-19 del), were found in the MIPEP gene, which were inherited from his healthy parents respectively. Additionally, his mitochondria DNA copy number was significantly reduced. Conclusion: We are the first to report a patient with rare MIPEP variants in China. Our findings expand the mutation spectrum of MIPEP, and provide insights into the genotype-phenotype relationship in COXPD31.
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Banana Fusarium wilt caused by Fusarium oxysporum f. sp. cubense is a disastrous fungal disease. Foc tropical race 4 (Foc TR4) infects almost all banana cultivars. Use of chemical fungicides caused serious environment pollution. Biological control with antagonistic microbes is a promising strategy for controlling Foc TR4. Here, strain WHL7 isolated from marine soft coral exhibited a high antifungal activity against Foc TR4. Based on the morphological and physicochemical profiles as well as the phylogenetic tree, the strain was assigned to Streptomyces sp. Fermentation broth of Streptomyces sp. WHL7 significantly increased the resistance of banana plantlets to Foc TR4 in the pot experiment. Analysis of antifungal mechanism showed that strain WHL7 extracts inhibited spore germination and mycelial growth of Foc TR4, and destroyed cell integrity and ultrastructure. Hence, Streptomyces sp. WHL7 is an important bioresource for exploring novel natural products and biofertilizer to manage Foc TR4.
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Antozoários , Agentes de Controle Biológico , Fusarium , Musa , Doenças das Plantas , Streptomyces , Animais , Antozoários/microbiologia , Fusarium/patogenicidade , Perfilação da Expressão Gênica , Musa/microbiologia , Filogenia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Streptomyces/fisiologiaRESUMO
Bacteria equipped with virulence systems based on highly bioactive small molecules can circumvent their host's defense mechanisms. Pathogens employing this strategy are currently threatening global rice production. In the present study, variations in the virulence of the highly destructive Burkholderia plantarii were observed in different rice-producing regions. The environment-linked variation was not attributable to any known host-related or external factors. Co-occurrence analyses indicated a connection between reduced virulence and 5-Amino-1,3,4-thiadiazole-2-thiol (ATT), a non-bactericidal organic compound. ATT, which accumulates in rice plants during metabolization of specific agrochemicals, was found to reduce virulence factor secretion by B. plantarii up to 88.8% and inhibit pathogen virulence by hijacking an upstream signaling cascade. Detailed assessment of the newly discovered virulence inhibitor resulted in mechanistic insights into positive effects of ATT accumulation in plant tissues. Mechanisms of virulence alleviation were deciphered by integrating high-throughput data, gene knockout mutants, and molecular interaction assays. TroK, a histidine protein kinase in a two-component system that regulates virulence factor secretion, is likely the molecular target antagonized by ATT. Our findings provide novel insights into virulence modulation in an important plant-pathogen system that relies on the host's metabolic activity and subsequent signaling interference.
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Strawberry is a very popular fruit with a special taste, color, and nutritional value. Anthracnose caused by Colletotrichum fragariae severely limits fruit shelf life during post-harvest storage. Use of traditional chemical fungicides leads to serious environment pollution and threatens food safety. Biocontrol is considered as a promising strategy to manage the post-harvest fruit diseases. Here, strain QN1NO-4 isolated from noni (Morinda citrifolia L.) fruit exhibited a high antifungal activity against C. fragariae. Based on its physicochemical profiles and phylogenetic tree of the 16S rRNA sequence, strain QN1NO-4 belonged to the genus Bacillus. The average nucleotide identity (ANI) calculated by comparing two standard strain genomes was below 95-96%, suggesting that the strain might be a novel species of the genus Bacillus and named as Bacillus safensis sp. QN1NO-4. Its extract effectively reduced the incidence of strawberry anthracnose of harvested fruit. Fruit weight and TSS contents were also maintained significantly. The antifungal mechanism assays indicated that the extract of the test antagonist inhibited mycelial growth and spore germination of C. fragariae in vitro. Cells of strain QN1NO-4 demonstrated the cytoplasmic heterogeneity, disappeared organelles, and ruptured ultrastructure. Notably, the strain extract also had a broad-spectrum antifungal activity. Compared with the whole genome of strain QN1NO-4, several functional gene clusters involved in the biosynthesis of active secondary metabolites were observed. Fifteen compounds were identified by gas chromatography-mass spectrometry (GC-MS). Hence, the fruit endophyte B. safensis sp. QN1NO-4 is a potential bio-agent identified for the management of post-harvest disease of strawberry fruit.
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An emerging experimental framework suggests that endocrine-disrupting compounds are candidate obesogens. However, this potential effect has not yet been determined for Tricresyl phosphate (TCP), a mass-produced organophosphate flame retardant (OPFR) that has been exposed to human beings in many ways. Many OPFRs, including TCP, have been shown to activate pregnane X receptor (PXR), a nuclear receptor that regulates lipid metabolism. Accordingly, we found that TCP exposure caused lipid accumulation in HepG2 cells in this study. Therefore, to elucidate the role of PXR played in TCP metabolism and promotion of lipid accumulation, HepG2 cells were exposed to different concentrations (5 × 10-8 to 5 × 10-5 M) of TCP for 24 h. The enlarged hepatic lipid droplets and increased hepatic triglyceride contents were observed in HepG2 cells after TCP exposure for 24 h. This is the result of a confluence of lipogenesis increase and ß-oxidation suppression imposed by PXR activation which was verified by the up regulation of genes in fatty acid (FA) synthesis and the down regulation of genes in ß-oxidation. Surface plasmon resonance (SPR) analysis and molecular docking revealed favorable binding mode of TCP to PXR and the knockout of PXR gene with CRISPR/cpf1 system in HepG2 cells abolished TCP-induced triglyceride accumulation, thus underlying the crucial role of PXR in hepatic lipid metabolism resulting from OPFRs exposure. This study enhances our understanding of molecular mechanisms and associations of PXR in lipid metabolism disturbance induced by TCP and provides novel evidence regarding the lipotoxicity effect and potential metabolism pathway of OPFRs.