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The vaginal microbiome is an immune defense against reproductive diseases and can serve as an important biomarker for cervical cancer. However, the intrinsic relationship between the recurrence and the vaginal microbiome in patients with cervical cancer before and after concurrent chemoradiotherapy is poorly understood. Here, we analyzed 125 vaginal microbial profiles from a patient cohort of stage IB-IVB cervical cancer using 16S metagenomic sequencing and deciphered the microbial composition and functional characteristics of the recurrent and non-recurrent both before and after chemoradiotherapy. We demonstrated that the abundance of beneficial bacteria and stability of the microbial community in the vagina decreased in the recurrence group, implying the unique characteristics of the vaginal microbiome for recurrent cervical cancer. Moreover, using machine learning, we identified Lactobacillus iners as the most important biomarker, combined with age and other biomarkers (such as Ndongobacter massiliensis, Corynebacterium pyruviciproducens ATCC BAA-1742, and Prevotella buccalis), and could predict cancer recurrence phenotype before chemoradiotherapy. This study prospectively employed rigorous bioinformatics analysis and highlights the critical role of vaginal microbiota in post-treatment cervical cancer recurrence, identifying promising biomarkers with prognostic significance in the context of concurrent chemoradiotherapy for cervical cancer. The role of L. iners in determining chemoradiation resistance in cervical cancer warrants further detailed investigation. Our results expand our understanding of cervical cancer recurrence and help develop better strategies for prognosis prediction and personalized therapy.
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Quimiorradioterapia , Lactobacillus , Microbiota , Recidiva Local de Neoplasia , Neoplasias do Colo do Útero , Vagina , Humanos , Feminino , Neoplasias do Colo do Útero/microbiologia , Neoplasias do Colo do Útero/terapia , Neoplasias do Colo do Útero/patologia , Vagina/microbiologia , Recidiva Local de Neoplasia/microbiologia , Pessoa de Meia-Idade , Adulto , Idoso , Aprendizado de MáquinaRESUMO
Vaginal microbiota is closely associated with women's health, however, the correlation between HPV-related cervical disease (HRCD) and vaginal microbiota is still obscure. In this study, patients with HRCD (n = 98) and healthy controls (n = 58) in Hangzhou were recruited, and their vaginal microbiota were collected and analyzed. The composition of the vaginal microbial community was explored, and a disease classification model was developed by random forest algorithm. The results suggested that the diversity of vaginal microbiota was significantly higher in HRCDs than that in healthy controls (p < 0.05). Firmicutes is the dominant phylum in vaginal microbiota, and Lactobacillus was identified as the most altered genus between two groups (p < 0.01). Kyoto Encyclopedia of Genes and Genomes analysis suggested the difference in vaginal microbial community functions between two groups. Furthermore, we identified 10 biomarkers as the optimal marker sets for the random forest model and found a higher probability of disease values in HRCD group in discovery cohort (p < 0.0001), with an area under the receiver operating characteristic curve reaching 89.7% (95% confidence interval: 78.3%-100%). We further validated the model in both validation and independent diagnosis cohorts, confirming its accuracy in the prediction of HRCD. In conclusion, this study revealed the community composition of vaginal microbiota in HRCDs and successfully constructed a diagnostic model for HRCD.
Assuntos
Microbiota , Infecções por Papillomavirus , Feminino , Humanos , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/diagnóstico , Papillomaviridae/genética , RNA Ribossômico 16S/genética , Papillomavirus Humano , Vagina , Microbiota/genéticaRESUMO
Freshwater cyanobacterial blooms have drawn public attention because they threaten the safety of water resources and human health worldwide. Heavy cyanobacterial blooms outbreak in Lake Taihu in summer annually and vanish in other months. To find out the factors impacting the cyanobacterial blooms, the present study measured the physicochemical parameters of water and investigated the composition of microbial community using the 16S rRNA gene and internal transcribed spacer amplicon sequencing in the months with or without bloom. The most interesting finding is that two major cyanobacteria, Planktothrix and Microcystis, dramatically alternated during a cyanobacterial bloom in 2016, which is less mentioned in previous studies. When the temperature of the water began increasing in July, Planktothrix appeared first and showed as a superior competitor for M. aeruginosa in NO3--rich conditions. Microcystis became the dominant genus when the water temperature increased further in August. Laboratory experiments confirmed the influence of temperature and the total dissolved nitrogen (TDN) form on the growth of Planktothrix and Microcystis in a co-culture system. Besides, species interactions between cyanobacteria and non-cyanobacterial microorganisms, especially the prokaryotes, also played a key role in the alteration of Planktothrix and Microcystis. The present study exhibited the alteration of two dominant cyanobacteria in the different bloom periods caused by the temperature, TDN forms as well as the species interactions. These results helped the better understanding of cyanobacterial blooms and the factors which contribute to them.
Assuntos
Cianobactérias , Microbiota , Microcystis , Cianobactérias/genética , Lagos , Microcystis/genética , RNA Ribossômico 16S/genéticaRESUMO
Physico-chemical parameters, hydrological conditions, and microbial interactions can affect the growth and persistence of cyanobacteria, but the interacting effects among these bloom-forming factors are still poorly known. This hampers our capacity to predict the occurrence of cyanobacterial bloom accurately. Here, we studied the relationship between temperature, N and P cycles, and the microbial community abundance and diversity at 0.5 m under the surface of West Lake (China) from January 21 to November 20, 2015, in order to better understand the key factors regulating temporal changes in the cyanobacterial community. Using high throughput sequencing of the 16S rRNA gene V3-V4 region, we studied the diversity and abundance of bacteria. In parallel, we measured physico-chemical parameters and followed the abundance of key genes involved in N fixation, denitrification, and nutrient uptake. Multivariate analyses suggest that P concentration and water temperature are the key factors controlling the outbreak of summer cyanobacterial bloom. RT-qPCR analyses of the bacterial community and measurements of the copy number of denitrification-related gene (nirK, nosZ, nirS) show that denitrification potential and denitrifying bacteria relative abundance (Pseudomonas and Bacillus) increased in concert with diazotrophic cyanobacterial genera (Anabaena, Nostoc, Aphanizomenon flos-aquae) and the common bloom-forming non-diazotrophic cyanobacterium genus Microcystis. The present study brings new insights on the complex interplay between physico-chemical parameters, heterotrophic bacterial community composition, nitrogen cycle, and cyanobacteria dominance in a eutrophic lake.
Assuntos
Cianobactérias/fisiologia , Lagos/microbiologia , Monitoramento Ambiental , Microbiologia da ÁguaRESUMO
Three ecotypes of Arabidopsis thaliana, ecotype Columbia (Wild type, Wt) and two mutants (pgr5 and ndf4), were used to evaluate the effects of diuron on photosynthetic activity of A. thaliana. It was found that diuron adversely affected the fresh weight and chlorophyll content of the plants. Chlorophyll fluorescence studies determined that the pgr5 mutant was more sensitive to diuron than Wt and the ndf4 mutant. Gene expression analysis revealed different roles for the two cyclic electron transfer (CET) pathways, NAD(P)H dehydrogenase (NDH) and proton gradient regulation (PGR5) pathways, in the plant after diuron treatment. For example, a gene in the NDH pathway, lhca5, was activated in the low dose (LD) group in the pgr5 mutant, but was down-regulated in the moderate dose (MD) group, along with two other NDH-related genes (ppl2 and ndhH). In the PGR5 pathway, the pgr5 gene was functional under conditions of increased stress (MD group), and was up-regulated to a greater extent in the ndf4 mutant than that in the Wt and pgr5 mutant. Our results suggest that the PGR5 pathway in plants is more important than the NDH pathway during resistance to environmental stress. Deficiencies in the PGR5 pathway could not be counteracted by the NDH pathway, but deficiencies in the NDH pathway could be overcome by stimulating PGR5.
Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Diurona/toxicidade , Transporte de Elétrons/efeitos dos fármacos , Herbicidas/toxicidade , Fotossíntese/efeitos dos fármacos , Complexo de Proteínas do Centro de Reação Fotossintética/genética , Arabidopsis/fisiologia , Transporte de Elétrons/genética , Mutação , Fotossíntese/genéticaRESUMO
Cyanobacterial blooms frequently occur in Lake Taihu (China), but the intertwined relationships between biotic and abiotic factors modulating the frequency and duration of the blooms remain enigmatic. To better understand the relationships between the key abiotic and biotic factors and cyanobacterial blooms, we measured the abundance and diversity of prokaryotic organisms by high-throughput sequencing, the abundance of key genes involved in microcystin production and nitrogen fixation or loss as well as several physicochemical parameters at several stations in Lake Taihu during a cyanobacterial bloom of Microcystis sp.. Measurements of the copy number of denitrification-related genes and 16S rRNA analyses show that denitrification potential and denitrifying bacteria abundance increased in concert with non-diazotrophic cyanobacteria (Microcystis sp.), suggesting limited competition between cyanobacteria and heterotrophic denitrifiers for nutrients, although potential bacteria-mediated N loss may hamper Microcystis growth. The present study provides insight into the importance of different abiotic and biotic factors in controlling cyanobacteria and heterotrophic bacteria spatial variability in Lake Taihu.
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Cianobactérias/crescimento & desenvolvimento , Monitoramento Ambiental , Lagos/microbiologia , China , Cianobactérias/classificação , Cianobactérias/genética , Microcistinas , Microcystis/crescimento & desenvolvimento , Fixação de Nitrogênio , RNA Ribossômico 16SRESUMO
Trace aluminum (Al) concentrations can be toxic to marine phytoplankton, the basis of the marine food web, but the fundamental Al toxicity and detoxification mechanisms at the molecular levels are poorly understood. Using an array of proteomic, transcriptomic, and biochemical techniques, we describe in detail the cellular response of the model marine diatom Phaeodactylum tricornutum to a short-term sublethal Al stress (4 h of exposure to 200 µM total initial Al). A total of 2204 proteins were identified and quantified by isobaric tags for relative and absolute quantification (iTRAQ) in response to the Al stress. Among them, 87 and 78 proteins performing various cell functions were up- and down-regulated after Al treatment, respectively. We found that photosynthesis was a key Al toxicity target. The Al-induced decrease in electron transport rates in thylakoid membranes lead to an increase in reactive oxygen species (ROS) production, which cause increased lipid peroxidation. Several ROS-detoxifying proteins were induced to help decrease Al-induced oxidative stress. In parallel, glycolysis and pentose phosphate pathway were up-regulated in order to produce cell energy (NADPH, ATP) and carbon skeleton for cell growth, partially circumventing the Al-induced toxicity effects on photosynthesis. These cellular responses to Al stress were coordinated by the activation of various signal transduction pathways. The identification of Al-responsive proteins in the model marine phytoplankton P. tricornutum provides new insights on Al stress responses as well as a good start for further exploring Al detoxification mechanisms.
Assuntos
Alumínio/toxicidade , Diatomáceas/metabolismo , Proteoma/metabolismo , Proteômica/métodos , Diatomáceas/efeitos dos fármacos , Diatomáceas/crescimento & desenvolvimento , Malondialdeído/metabolismo , Fotossíntese/efeitos dos fármacos , Fotossíntese/genética , Pigmentos Biológicos/metabolismo , Proteoma/genética , Espécies Reativas de Oxigênio/metabolismo , Transcrição Gênica/efeitos dos fármacosRESUMO
The aim of the present study was to investigate the protective effect of ammonium (NH4 (+)) on Cr toxicity to the freshwater alga Chlorella vulgaris. We followed an array of cellular functions and biomolecules in C. vulgaris cells exposed to 50 or 100 µM Cr at three different initial NH4 (+) concentrations (0.5, 3, and 10 mM). The results showed that Cr strongly inhibited cell yield of C. vulgaris, but 10 mM NH4 (+) could decrease by more than two-fold Cr toxicity on cell yield compared to exposure to 0.5 mM NH4 (+). Cr toxicity on gene transcripts and cellular substructure was also much lower at high than at low NH4 (+). Our results suggest that this protecting effect of NH4 (+) on intracellular Cr toxicity could be due to several factors, such as enhance uptake of phosphorus, increase in C and N assimilation efficiency, and increase transcription of photosynthesis-related genes.
Assuntos
Compostos de Amônio/farmacologia , Chlorella vulgaris/efeitos dos fármacos , Chlorella vulgaris/crescimento & desenvolvimento , Cromo/toxicidade , Chlorella vulgaris/metabolismo , Cloro/metabolismo , Clorofila/metabolismo , Cromo/farmacocinética , Relação Dose-Resposta a Droga , Água Doce , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Fósforo/análise , Fósforo/metabolismo , Fotossíntese/efeitos dos fármacos , Fotossíntese/genética , Enxofre/metabolismo , Poluentes Químicos da Água/toxicidadeRESUMO
Microbial communities play a crucial role in ocean ecology and global biogeochemical processes. However, understanding the intricate interactions among diversity, taxonomical composition, functional traits, and how these factors respond to climate change remains a significant challenge. Here, we propose seven distinct ecological statuses by systematically considering the diversity, structure, and biogeochemical potential of the ocean microbiome to delineate their biogeography. Anthropogenic climate change is expected to alter the ecological status of the surface ocean by influencing environmental conditions, particularly nutrient and oxygen contents. Our predictive model, which utilizes machine learning, indicates that the ecological status of approximately 32.44% of the surface ocean may undergo changes from the present to the end of this century, assuming no policy interventions. These changes mainly include poleward shifts in the main taxa, increases in photosynthetic carbon fixation and decreases in nutrient metabolism. However, this proportion can decrease significantly with effective control of greenhouse gas emissions. Our study underscores the urgent necessity for implementing policies to mitigate climate change, particularly from an ecological perspective.
Assuntos
Mudança Climática , Microbiota , Oceanos e Mares , Água do Mar/microbiologia , Ecossistema , Ciclo do Carbono , BiodiversidadeRESUMO
The relative abundance of single-exon genes (SEGs) in higher plants is perplexing. Uncovering the synonymous codon usage pattern of SEGs will benefit for further understanding their underlying evolutionary mechanism in plants. Using internal correspondence analysis (ICA), we reveal a significant difference in synonymous codon usage between SEGs and multiple-exon genes (MEGs) in rice. But the effect is weak, accounting for only 2.61% of the total codon usage variability. SEGs and MEGs contain remarkably different base compositions, and are under clearly differential selective constraints, with the former having higher GC content, and evolving relatively faster during evolution. In the group of SEGs, the variability in synonymous codon usage among genes is partially due to the variations in GC content, gene function, and gene expression level, which accounts for 22.03%, 5.99%, and 3.32% of the total codon usage variability, respectively. Therefore, mutational bias and natural selection should work on affecting the synonymous codon usage of SEGs in rice. These findings may deepen our knowledge for the mechanisms of origination, differentiation and regulation of SEGs in plants.
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This study was conducted to evaluate the effect of licorice and rutin on production performance, egg quality, and mucosa antioxidant levels in Chinese yellow quail. A total of 240 Chinese Yellow Quail (400-day-old) were randomly distributed into 5 groups: the Control group, fed with a basic diet; the LR1 group, fed with basal diet supplemented with 300 + 100 mg licorice and rutin mixture/kg diet; the LR2 group, fed with basal diet supplemented with 300 + 200 mg licorice and rutin mixture/kg diet; the LR3 group, fed with basal diet supplemented with 600 + 100 mg licorice and rutin mixture/kg diet and the LR4 group, fed with basal diet supplemented with 600 + 200 mg licorice and rutin mixture/kg diet. Compared with the control, supplementation with the licorice and rutin mixture improved the laying rate and eggshell thickness whereas decreased the feed conversion ratio of quails. Moreover, dietary supplementation with the licorice and rutin mixture improved the antioxidant capacity by increasing the activity of the superoxide dismutase (SOD) level and decreasing the concentration of malondialdehyde (MDA) in the jejunal mucosa. The licorice and rutin mixture altered the composition of intestinal microbiota by influencing the relative abundances of Bacteroidetes and Bacteroides. The relative abundances of the Bacteroidetes were significantly related to the laying rate of quails. In addition, the mixture of licorice and rutin was also effective in reducing the relative abundance of intestinal Proteobacteria and Enterobacter in quails, reducing the accumulation of antibiotic-resistance genes. The results revealed that supplementation of licorice and rutin mixture to the diet improved production performance, egg quality, and antioxidant capacity and modified the composition of intestinal microbiota in quails. This study provides a reference for Chinese herbal additives to promote production performance by modulating quail gut microbes.
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Background: Immune status is widely acknowledged as a valuable marker for predicting cancer prognosis and therapy response. However, there has been a limited understanding of the stromal landscape in cancer. Methods: By employing ESTIMATE, stromal- and immune-scores were inferred for 6193 tumor samples spanning 12 cancer types sourced from The Cancer Genome Atlas (TCGA). Subsequently, the samples were categorized into seven groups based on their stromal and immune scores. A comparison of prognosis, lymphocyte and stromal cell infiltration, and the response to programmed death ligand 1 (PD-L1) therapy was conducted among these subtypes. Results: It was unveiled by the analysis that, in the majority of cancer types, stromal score exhibited a more potent predictive capability for outcomes compared to the immune score. Furthermore, it was observed that in four cancer types, intermediate immune infiltration coupled with low stromal infiltration correlated with the most favorable overall survival, whereas an unfavorable outcome was predicted in colorectal cancer (CRC) and stomach adenocarcinoma (STAD) when high immune infiltration coexisted with intermediate or high stromal infiltration. Conclusion: In summary, while high immune scores frequently correlate with a positive prognosis, such correlation is not universal. A potential strategy to address the current limitations of the immune score in specific circumstances could involve a focus on stromal scores or a subtle integration of stromal and immune status.
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Microcystis aeruginosa, a primary species in cyanobacterial blooms, is ubiquitously distributed in water. Microcystins (MCs) purified from M. aeruginosa can exert reproductive toxicity in fish. However, the effects of M. aeruginosa at environmentally relevant levels on the reproductive and endocrine systems of zebrafish are still unknown. The present study investigated the reproductive and endocrine-disrupting toxicity of M. aeruginosa on female zebrafish (Danio rerio) by short-term exposure (96 h). After exposure, marked histological lesions in the liver or gonads, such as nuclear pyknosis and deformation, were observed, and the fertilization rate and hatchability of eggs spawned from treated females were both significantly lower than they were in females in the control group, suggesting the possibility of transgenerational effects of M. aeruginosa exposure. Moreover, M. aeruginosa exposure decreased the concentration of 17ß-estradiol (E2) and testosterone (T) in female zebrafish. Interestingly, the vtg1 transcriptional level significantly decreased in the liver, whereas plasma vitellogenin (VTG) protein levels increased. The present findings indicate that M. aeruginosa could modulate endocrine function by disrupting transcription of hypothalamic-pituitary-gonadal-liver (HPGL) axis-related genes, and impair the reproductive capacity of female zebrafish, suggesting that M. aeruginosa causes potential adverse effects on fish reproduction in Microcystis bloom-contaminated aquatic environments.
Assuntos
Sistema Endócrino/efeitos dos fármacos , Microcistinas/toxicidade , Microcystis/patogenicidade , Reprodução/efeitos dos fármacos , Peixe-Zebra/microbiologia , Animais , Toxinas Bacterianas/farmacologia , Disruptores Endócrinos/farmacologia , Estradiol/análise , Estradiol/metabolismo , Feminino , Gônadas/efeitos dos fármacos , Gônadas/metabolismo , Gônadas/patologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Microcistinas/isolamento & purificação , Microcystis/metabolismo , Testosterona/análise , Testosterona/sangue , Vitelogeninas/sangue , Vitelogeninas/metabolismo , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo , Peixe-Zebra/fisiologia , Proteínas de Peixe-Zebra/análise , Proteínas de Peixe-Zebra/efeitos dos fármacos , Proteínas de Peixe-Zebra/genéticaRESUMO
BACKGROUND: Plant phenology has crucial biological, physical, and chemical effects on the biosphere. Phenological drivers have largely been studied, but the role of plant microbiota, particularly rhizosphere microbiota, has not been considered. RESULTS: We discovered that rhizosphere microbial communities could modulate the timing of flowering of Arabidopsis thaliana. Rhizosphere microorganisms that increased and prolonged N bioavailability by nitrification delayed flowering by converting tryptophan to the phytohormone indole acetic acid (IAA), thus downregulating genes that trigger flowering, and stimulating further plant growth. The addition of IAA to hydroponic cultures confirmed this metabolic network. CONCLUSIONS: We document a novel metabolic network in which soil microbiota influenced plant flowering time, thus shedding light on the key role of soil microbiota on plant functioning. This opens up multiple opportunities for application, from helping to mitigate some of the effects of climate change and environmental stress on plants (e.g. abnormal temperature variation, drought, salinity) to manipulating plant characteristics using microbial inocula to increase crop potential.
Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/microbiologia , Bactérias/metabolismo , Flores/crescimento & desenvolvimento , Ácidos Indolacéticos/metabolismo , Nitrogênio/metabolismo , Complexo de Proteínas do Centro de Reação Fotossintética/genética , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Bactérias/classificação , Fenômenos Fisiológicos Bacterianos , Regulação para Baixo , Flores/genética , Flores/microbiologia , Regulação Bacteriana da Expressão Gênica , Metagenômica , Mutação , Filogenia , Rizosfera , Microbiologia do Solo , Triptofano/metabolismoRESUMO
Diclofop-methyl (DM), a common post-emergence herbicide, is frequently used in agricultural production. Silver nanoparticles (AgNPs) are one of the most widely used nanoparticles, and as such, have been detected and monitored in several environmental systems. Here we investigated the interactive effects of DM and AgNPs on the physiological morphology, photosynthesis and antioxidant system of Arabidopsis thaliana. Our results demonstrated that a 1.0 mg/L DM treatment had no significant effect on the fresh weight of plant shoots and the content of total chlorophyll and anthocyanin. However, a 0.5 mg/L AgNPs treatment was found to significantly inhibit plant growth and chlorophyll synthesis, and was found to cause more severe oxidative damage in plants compared to the effects observed in a hydroponic suspension in which DM and AgNPs were jointly present. Meanwhile, the relative transcript levels of photosynthesis related genes (psbA, rbcL, pgrl1A and pgrl1B) in the combined group were found to be slightly increased compared to transcript levels in the AgNPs group, in order to maintain ATP generation at relatively normal levels in order to repair light damage. One explanation for these observed antagonistic effects was that the existence of DM affects the stability of AgNPs and reduced Ag+ release from AgNPs in the mixed solution. Thereupon, the Ag+-content was found to decrease in shoots and roots in the combined group by 15.2% and 9.4% respectively, compared to the AgNPs group. The coexistence of herbicides and nanomaterials in aquatic environments or soil systems will continue to exist due to their wide usages. Our current study highlights that the antagonistic effects between DM and AgNPs exerted a positive impact on A. thaliana growth.
Assuntos
Arabidopsis/fisiologia , Éteres Difenil Halogenados/toxicidade , Substâncias Perigosas/toxicidade , Nanopartículas Metálicas/toxicidade , Prata/toxicidade , Antioxidantes/metabolismo , Arabidopsis/efeitos dos fármacos , Clorofila/metabolismo , Éteres Difenil Halogenados/química , Fotossíntese/efeitos dos fármacos , Raízes de Plantas/metabolismo , Brotos de Planta/efeitos dos fármacos , Prata/metabolismoRESUMO
Carbon nanotubes can be either toxic or beneficial to plant growth and can also modulate toxicity of organic contaminants through surface sorption. The complex interacting toxic effects of carbon nanotubes and organic contaminants in plants have received little attention in the literature to date. In this study, the toxicity of multiwall carbon nanotubes (MWCNT, 50 mg/L) and paraquat (MV, 0.82 mg/L), separately or in combination, were evaluated at the physiological and the proteomic level in Arabidopsis thaliana for 7-14 days. The results revealed that the exposure to MWCNT had no inhibitory effect on the growth of shoots and leaves. Rather, MWCNT stimulated the relative electron transport rate and the effective photochemical quantum yield of PSII value as compared to the control by around 12% and lateral root production up to nearly 4-fold as compared to the control. The protective effect of MWCNT on MV toxicity on the root surface area could be quantitatively explained by the extent of MV adsorption on MWCNT and was related to stimulation of photosynthesis, antioxidant protection and number and area of lateral roots which in turn helped nutrient assimilation. The influence of MWCNT and MV on photosynthesis and oxidative stress at the physiological level was consistent with the proteomics analysis, with various over-expressed photosynthesis-related proteins (by more than 2 folds) and various under-expressed oxidative stress related proteins (by about 2-3 folds). This study brings new insights into the interactive effects of two xenobiotics (MWCNT and MV) on the physiology of a model plant.
Assuntos
Arabidopsis/fisiologia , Herbicidas/toxicidade , Nanotubos de Carbono/química , Paraquat/toxicidade , Adsorção , Arabidopsis/metabolismo , Transporte de Elétrons , Estresse Oxidativo/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , ProteômicaRESUMO
Nano-aluminium oxide (nAl2O3) is one of the most widely used nanomaterials. However, nAl2O3 toxicity mechanisms and potential beneficial effects on terrestrial plant physiology remain poorly understood. Such knowledge is essential for the development of robust nAl2O3 risk assessment. In this study, we studied the influence of a 10-d exposure to a total selected concentration of 98 µM nAl2O3 or to the equivalent molar concentration of ionic Al (AlCl3) (196 µM) on the model plant Arabidopsis thaliana on the physiology (e.g., growth and photosynthesis, membrane damage) and the transcriptome using a high throughput state-of-the-art technology, RNA-seq. We found no evidence of nAl2O3 toxicity on photosynthesis, growth and lipid peroxidation. Rather the nAl2O3 treatment stimulated root weight and length by 48% and 39%, respectively as well as photosynthesis opening up the door to the use of nAl2O3 in biotechnology and nano agriculture. Transcriptomic analyses indicate that the beneficial effect of nAl2O3 was related to an increase in the transcription of several genes involved in root growth as well as in root nutrient uptake (e.g., up-regulation of the root hair-specific gene family and root development genes, POLARIS protein). By contrast, the ionic Al treatment decreased shoot and root weight of Arabidopsis thaliana by 57.01% and 45.15%, respectively. This toxic effect was coupled to a range of response at the gene transcription level including increase transcription of antioxidant-related genes and transcription of genes involved in plant defense response to pathogens. This work provides an integrated understanding at the molecular and physiological level of the effects of nAl2O3 and ionic Al in Arabidopsis.
Assuntos
Óxido de Alumínio/toxicidade , Alumínio/toxicidade , Arabidopsis/fisiologia , Nanopartículas/toxicidade , Antioxidantes/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/metabolismo , Perfilação da Expressão Gênica , Peroxidação de Lipídeos/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Raízes de Plantas/metabolismo , Testes de Toxicidade , Transcriptoma/efeitos dos fármacos , Regulação para CimaRESUMO
The frequency and intensity of cyanobacterial blooms are increasing worldwide with major societal and economic costs. Interactions between toxic cyanobacteria and eukaryotic algal competitors can affect toxic bloom formation, but the exact mechanisms of interspecies interactions remain unknown. Using metabolomic and proteomic profiling of co-cultures of the toxic cyanobacterium Microcystis aeruginosa with a green alga as well as of microorganisms collected in a Microcystis spp. bloom in Lake Taihu (China), we disentangle novel interspecies allelopathic interactions. We describe an interspecies molecular network in which M. aeruginosa inhibits growth of Chlorella vulgaris, a model green algal competitor, via the release of linoleic acid. In addition, we demonstrate how M. aeruginosa takes advantage of the cell signaling compound nitric oxide produced by C. vulgaris, which stimulates a positive feedback mechanism of linoleic acid release by M. aeruginosa and its toxicity. Our high-throughput system-biology approach highlights the importance of previously unrecognized allelopathic interactions between a broadly distributed toxic cyanobacterial bloom former and one of its algal competitors.
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Alelopatia/fisiologia , Chlorella vulgaris/fisiologia , Ácido Linoleico/farmacologia , Microcystis/efeitos dos fármacos , Microcystis/fisiologia , Óxido Nítrico/farmacologia , Técnicas de Cocultura , Cianobactérias/crescimento & desenvolvimento , ProteômicaRESUMO
The widely used solvent extractant, tributyl phosphate (TBP), primarily used as a solvent for the conventional processing of nuclear fuel, has come under scrutiny recently due to concerns surrounding potential environmental contamination and toxicity. In this study, we found that, in Phaeodactylum tricornutum, administration of TBP severely inhibited algal cell growth by reducing photosynthetic efficiency and inducing oxidative stress. We further explored the effect of TBP by examining the gene expression of the photosynthetic electron transport chain and its contribution to reactive oxygen species (ROS) burst. Our data revealed that TBP affected both fatty acid content and profile by regulating the transcription of genes related to glycolysis, fatty acid biosynthesis, and ß-oxidation. These results demonstrated that TBP did in fact trigger the synthesis of ROS, disrupting the subcellular membrane structure of this aquatic organism. Our study brings new insight into the fundamental mechanism of toxicity exerted by TBP on the marine alga P. tricornutum.