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1.
Ecotoxicol Environ Saf ; 207: 111198, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32905932

RESUMO

Cd pollution in farmland is becoming a serious problem because it affects the safety of rice production and human health. Salicylic acid (SA) plays crucial roles in plant development and mediates plant responses to biotic and abiotic stress. This study assessed the molecular and physiological mechanisms of SA spraying effects on Cd tolerance and Cd accumulation in rice. Spraying of 0.1 mM SA had no great effect on the agronomic traits of rice, but significantly decreased Cd accumulation in rice grains, and SA spraying increased the Cd contents in leaves (only at the mature stage) and decreased the Cd contents in panicles (only at the filling and mature stage), but had no evident impact on the Cd content of other tissues and other growth stages. SA spraying reduced Cd accumulation in rice grains by promoting the deposition and fixation of Cd in the cell wall of leaves, thus preventing Cd being transferred from leaves to rice grains at the filling stage. SA spraying also decreased Cd toxicity by reducing H2O2 and MDA accumulation and increasing the chlorophyll content in rice leaves. Furthermore, SA spraying remarkably decreased Cd accumulation in rice grains by modulating the expression level of the genes associated with Cd translocation and accumulation to control the Cd accumulation in rice. Hence, SA spraying reduced the inhibition of Cd on the plant height caused by Cd and increased the dry weight of shoots in the vegetative growth period of rice seedlings, and it reduced Cd transport from leaves to grains, thus reducing Cd content in rice. These findings provide a novel perspective and a new method for reducing Cd accumulation in rice.


Assuntos
Cádmio/toxicidade , Oryza/metabolismo , Substâncias Protetoras/farmacologia , Ácido Salicílico/farmacologia , Poluentes do Solo/toxicidade , Cádmio/metabolismo , Clorofila/metabolismo , Poluição Ambiental , Humanos , Peróxido de Hidrogênio/metabolismo , Folhas de Planta/metabolismo , Plântula/efeitos dos fármacos , Poluentes do Solo/metabolismo , Estresse Fisiológico/efeitos dos fármacos
2.
Ecotoxicol Environ Saf ; 207: 111248, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32927156

RESUMO

Drought is one of the most common factors that limit plant growth and productivity. Sulfur dioxide (SO2) has recently been found to play a benefical role in protection of plants against environmental stress. In this study, we investigated the effect of SO2 on the physiological and molecular response of wheat seedlings to drought stress. Pretreatment with 10 mg/m3 SO2 significantly increased the survival rate and relative water content (RWC) of wheat seedlings under drought stress, indicating that pre-exposure to appropriate level of SO2 could enhance drought tolerance of plants. These responses were related to the enhanced proline accumulation in the drought-treated wheat seedlings that induced by SO2 pretreatment. Meanwhile, SO2 pretreatment increased the activities of superoxide dismutase (SOD) and peroxidase (POD), and effectively reduced the content of hydrogen peroxide (H2O2) and malondialdehyde (MDA) in drought-treated wheat seedlings, suggesting SO2 could alleviate drought-induced oxidative damage by enhancing antioxidant defense system in plants. Expression analysis of transcription factor genes also showed that SO2 pretreatment decreased the expression of TaNAC69, but the expression of TaERF1 and TaMYB30 changed slightly and maintained at higher levels in wheat seedlings in response to drought stress. Furthermore, SO2 pretreatment triggered marked accumulation of hydrogen sulfide (H2S) in wheat seedlings under drought stress. When scavenged H2S by spraying Hypotaurine (HT), the activities of antioxidant enzymes and the expression of transcription factor genes were decreased, and the content of H2O2 and MDA increased to the level of drought treatment alone, suggesting a regulatory role of SO2-induced H2S in plant adaptation to drought stress. Together, this study indicated that SO2 enhanced drought tolerance of wheat seedlings through H2S signaling, and provided new strategy for enhancing plant tolerance to drought stress.


Assuntos
Secas , Dióxido de Enxofre/análise , Triticum/fisiologia , Adaptação Fisiológica/efeitos dos fármacos , Antioxidantes/metabolismo , Peróxido de Hidrogênio/metabolismo , Sulfeto de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Oxirredutases/metabolismo , Desenvolvimento Vegetal , Plântula/metabolismo , Transdução de Sinais , Estresse Fisiológico/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Triticum/efeitos dos fármacos
3.
Nat Commun ; 11(1): 6330, 2020 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-33303737

RESUMO

Endothelial cell (EC) metabolism is thought to be one of the driving forces for angiogenesis. Here we report the identification of the hexosamine D-mannosamine (ManN) as an EC mitogen and survival factor for bovine and human microvascular EC, with an additivity with VEGF. ManN inhibits glycosylation in ECs and induces significant changes in N-glycan and O-glycan profiles. We further demonstrate that ManN and two N-glycosylation inhibitors stimulate EC proliferation via both JNK activation and the unfolded protein response caused by ER stress. ManN results in enhanced angiogenesis in a mouse skin injury model. ManN also promotes angiogenesis in a mouse hindlimb ischemia model, with accelerated limb blood flow recovery compared to controls. In addition, intraocular injection of ManN induces retinal neovascularization. Therefore, activation of stress pathways following inhibition of protein glycosylation can promote EC proliferation and angiogenesis and may represent a therapeutic strategy for treatment of ischemic disorders.


Assuntos
Neovascularização Fisiológica , Proteínas/metabolismo , Estresse Fisiológico , Animais , Bovinos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Ativação Enzimática/efeitos dos fármacos , Feminino , Glicosilação/efeitos dos fármacos , Proteínas de Choque Térmico/metabolismo , Hexosaminas/farmacologia , Membro Posterior/patologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Isquemia/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Microvasos/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Fluxo Sanguíneo Regional/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Pele/patologia , Estresse Fisiológico/efeitos dos fármacos , Fator de Transcrição CHOP/metabolismo , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/farmacologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Cicatrização/efeitos dos fármacos
4.
PLoS Genet ; 16(11): e1009117, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33201894

RESUMO

Glioblastoma is the most common and aggressive type of cancer in the brain; its poor prognosis is often marked by reoccurrence due to resistance to the chemotherapeutic agent temozolomide, which is triggered by an increase in the expression of DNA repair enzymes such as MGMT. The poor prognosis and limited therapeutic options led to studies targeted at understanding specific vulnerabilities of glioblastoma cells. Metabolic adaptations leading to increased synthesis of nucleotides by de novo biosynthesis pathways are emerging as key alterations driving glioblastoma growth. In this study, we show that enzymes necessary for the de novo biosynthesis of pyrimidines, DHODH and UMPS, are elevated in high grade gliomas and in glioblastoma cell lines. We demonstrate that DHODH's activity is necessary to maintain ribosomal DNA transcription (rDNA). Pharmacological inhibition of DHODH with the specific inhibitors brequinar or ML390 effectively depleted the pool of pyrimidines in glioblastoma cells grown in vitro and in vivo and impaired rDNA transcription, leading to nucleolar stress. Nucleolar stress was visualized by the aberrant redistribution of the transcription factor UBF and the nucleolar organizer nucleophosmin 1 (NPM1), as well as the stabilization of the transcription factor p53. Moreover, DHODH inhibition decreased the proliferation of glioblastoma cells, including temozolomide-resistant cells. Importantly, the addition of exogenous uridine, which reconstitutes the cellular pool of pyrimidine by the salvage pathway, to the culture media recovered the impaired rDNA transcription, nucleolar morphology, p53 levels, and proliferation of glioblastoma cells caused by the DHODH inhibitors. Our in vivo data indicate that while inhibition of DHODH caused a dramatic reduction in pyrimidines in tumor cells, it did not affect the overall pyrimidine levels in normal brain and liver tissues, suggesting that pyrimidine production by the salvage pathway may play an important role in maintaining these nucleotides in normal cells. Our study demonstrates that glioblastoma cells heavily rely on the de novo pyrimidine biosynthesis pathway to generate ribosomal RNA (rRNA) and thus, we identified an approach to inhibit ribosome production and consequently the proliferation of glioblastoma cells through the specific inhibition of the de novo pyrimidine biosynthesis pathway.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Nucléolo Celular/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Pirimidinas/biossíntese , Animais , Antineoplásicos/uso terapêutico , Compostos de Bifenilo/farmacologia , Compostos de Bifenilo/uso terapêutico , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Nucléolo Celular/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Glioblastoma/patologia , Humanos , Camundongos , Complexos Multienzimáticos/antagonistas & inibidores , Complexos Multienzimáticos/metabolismo , Orotato Fosforribosiltransferase/antagonistas & inibidores , Orotato Fosforribosiltransferase/metabolismo , Orotidina-5'-Fosfato Descarboxilase/antagonistas & inibidores , Orotidina-5'-Fosfato Descarboxilase/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/antagonistas & inibidores , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/metabolismo , RNA Ribossômico/biossíntese , Ribossomos/efeitos dos fármacos , Ribossomos/metabolismo , Estresse Fisiológico/efeitos dos fármacos , Transcrição Genética/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
5.
PLoS One ; 15(11): e0242221, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33216769

RESUMO

An economically valuable woody plant species tree bean (Cajanus cajan (L.) Millsp.) is predominantly cultivated in tropical and subtropical areas and is regarded as an important food legume (or pulse) crop that is facing serious sodium ion stress. NAM (N-acetyl-5-methoxytryptamine) has been implicated in abiotic and biotic stress tolerance in plants. However, the role of NAM in sodium ion stress tolerance has not been determined. In this study, the effect of NAM was investigated in the economically valuable woody plant species, challenged with stress at 40 mM sodium ion for 3 days. NAM-treated plants (200 µM) had significantly higher fresh weight, average root length, significantly reduced cell size, increased cell number, and increased cytoskeleton filaments in single cells. The expression pattern of one of 10 Tree bean Dynamic Balance Movement Related Protein (TbDMP), TbDMP was consistent with the sodium ion-stress alleviation by NAM. Using TbDMP as bait, Dynamic Balance Movement Related Kinase Protein (TbDBK) was determined to interact with TbDMP by screening the tree bean root cDNA library in yeast. Biochemical experiments showed that NAM enhanced the interaction between the two proteins which promoted resist sodium ion stress resistance. This study provides evidence of a pathway through which the skeleton participates in NAM signaling.


Assuntos
Cajanus/metabolismo , Proteínas de Plantas/metabolismo , Cloreto de Sódio/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Cajanus/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Íons/química , Filogenia , Folhas de Planta/metabolismo , Proteínas de Plantas/classificação , Proteínas de Plantas/genética , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/metabolismo , Serotonina/análogos & derivados , Serotonina/farmacologia , Tabaco/metabolismo
6.
Aquat Toxicol ; 229: 105670, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33166902

RESUMO

Antibiotics have been widely used (mainly mixed with feed) in aquaculture, while few studies have evaluated the interactions between feed composition and antibiotics. Sulfamethoxazole (SMX) is a fat-soluble antibiotic, an eight weeks feeding trial was conducted to investigate the interactions between dietary lipid levels and chronic exposure of legal aquaculture dose of sulfamethoxazole in juvenile largemouth bass Micropterus salmoides, and evaluated the possible human health risk. Six practical diets were formulated to three levels of crude lipid (11, 14.5, 18 %) and two levels of SMX (0 and 0.3 %), namely low fat (LF), moderate fat (MF), high fat (HF), low fat and SMX (LFS), moderate fat and SMX (MFS), high fat and SMX (HFS), respectively. Each diet was assigned to three tanks (20 fish per tank, average weight 30.65 ± 0.02 g). Growth and organ indices were increased by SMX. Higher malformation rate and lower hypoxia stress resistance were found in fish exposed to SMX than those not exposed. Cholesterol and bile acid synthesis related gene expressions were down-regulated by SMX exposure. Oxidative stress, inflammation and apoptosis were increased in fish exposed to SMX. Significant interactions between dietary lipid levels and SMX on renal immune response of fish were observed. Remarkable damage of intestinal histology was observed in fish fed the diet HFS. In addition, dietary SMX exposure increased pathogen susceptibility of largemouth bass and induced dysbiosis of gut microbiota. The concentrations of SMX in muscle of fish fed diets containing SMX were higher than those fed other diets, and close to the maximum residue limit (MRL) in China and international organizations. Although chronic legal aquaculture dose of dietary SMX also increased the target hazard quotient (THQ) and estimated daily intake (EDI), there is no health risk in adults and children consuming fish filet.


Assuntos
Aquicultura , Bass/metabolismo , Exposição Dietética , Gorduras na Dieta/farmacologia , Sulfametoxazol/toxicidade , Animais , Antioxidantes/metabolismo , Bass/sangue , Bass/crescimento & desenvolvimento , Bass/imunologia , China , Microbioma Gastrointestinal/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Hipóxia/genética , Intestinos/efeitos dos fármacos , Rim/efeitos dos fármacos , Rim/imunologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/genética , Fígado/efeitos dos fármacos , Fígado/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genética , Poluentes Químicos da Água/toxicidade
7.
Aquat Toxicol ; 229: 105678, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33197688

RESUMO

The rotifer, Brachionus plicatilis, is a widely used model species in marine ecotoxicology for evaluating pollutions, toxins, and harmful algae. In this paper, the marine ecotoxicology of Brachionus plicatilis was reviewed, including toxicity measurements of harmful algae species and environmental stresses. In addition, marine pollution involving pesticides, heavy metals, drugs, petroleum, and petrochemicals were addressed. Methods for measuring toxicity were also discussed. The standard acute lethal assay and the chronic population dynamics test were indicated as common methods of toxicity evaluating using B. plicatilis. Research on other biomarkers, such as behaviour, enzyme activity, or gene expression, are also reported here, with potential applications for fast detection or the scientific exploration of underlying molecular mechanisms. It is suggested that the methods selected should reflect the experimental purpose. Additionally, series assays should be conducted for comprehensive evaluation of ecotoxicity as well as to elucidate the correct mechanisms. Genetic methods, such as transcriptomics, were suggested as useful tools for exploring the toxicity mechanism using the rotifer B. plicatilis.


Assuntos
Ecossistema , Ecotoxicologia , Rotíferos/fisiologia , Animais , Rotíferos/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Testes de Toxicidade , Poluentes Químicos da Água/toxicidade
8.
Nucleic Acids Res ; 48(20): 11408-11420, 2020 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-33084907

RESUMO

While expression of ribosomal protein genes (RPGs) in the budding yeast has been extensively studied, a longstanding enigma persists regarding their co-regulation under fluctuating growth conditions. Most RPG promoters display one of two distinct arrangements of a core set of transcription factors (TFs) and are further differentiated by the presence or absence of the HMGB protein Hmo1. However, a third group of promoters appears not to be bound by any of these proteins, raising the question of how the whole suite of genes is co-regulated. We demonstrate here that all RPGs are regulated by two distinct, but complementary mechanisms driven by the TFs Ifh1 and Sfp1, both of which are required for maximal expression in optimal conditions and coordinated downregulation upon stress. At the majority of RPG promoters, Ifh1-dependent regulation predominates, whereas Sfp1 plays the major role at all other genes. We also uncovered an unexpected protein homeostasis-dependent binding property of Hmo1 at RPG promoters. Finally, we show that the Ifh1 paralog Crf1, previously described as a transcriptional repressor, can act as a constitutive RPG activator. Our study provides a more complete picture of RPG regulation and may serve as a paradigm for unravelling RPG regulation in multicellular eukaryotes.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Regulação Fúngica da Expressão Gênica , Proteínas de Grupo de Alta Mobilidade/metabolismo , Proteínas Ribossômicas/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Estresse Fisiológico/genética , Transativadores/metabolismo , Transcrição Genética , Sequenciamento de Cromatina por Imunoprecipitação , Proteínas de Ligação a DNA/genética , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Proteínas de Grupo de Alta Mobilidade/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Regiões Promotoras Genéticas , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Proteínas Ribossômicas/biossíntese , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Sirolimo/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Transativadores/genética
9.
Nat Commun ; 11(1): 5026, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-33024104

RESUMO

How to design experiments that accelerate knowledge discovery on complex biological landscapes remains a tantalizing question. We present an optimal experimental design method (coined OPEX) to identify informative omics experiments using machine learning models for both experimental space exploration and model training. OPEX-guided exploration of Escherichia coli's populations exposed to biocide and antibiotic combinations lead to more accurate predictive models of gene expression with 44% less data. Analysis of the proposed experiments shows that broad exploration of the experimental space followed by fine-tuning emerges as the optimal strategy. Additionally, analysis of the experimental data reveals 29 cases of cross-stress protection and 4 cases of cross-stress vulnerability. Further validation reveals the central role of chaperones, stress response proteins and transport pumps in cross-stress exposure. This work demonstrates how active learning can be used to guide omics data collection for training predictive models, making evidence-driven decisions and accelerating knowledge discovery in life sciences.


Assuntos
Biologia Computacional/métodos , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Modelos Biológicos , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Desinfetantes/farmacologia , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Aprendizado de Máquina , Proteínas de Membrana/genética , Chaperonas Moleculares/genética , Projetos de Pesquisa , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genética
10.
Aquat Toxicol ; 229: 105579, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33075615

RESUMO

Effective phytoremediation by aquatic plant such as duckweed could be applied to solve Cd pollution. In the present study, the impact of Graphene oxide (GO) on the accumulation of Cd in duckweed has been studied. The response of duckweed was also investigated, concluding growth, Cd2+ flux, and gene expression response. Results showed that GO promoted the accumulation of Cd in duckweed. After 6 h of Cd enrichment in duckweed, Cd content was about 1.4 times that of the control group at fronds and 1.25 times that of the control group at roots, meanwhile, Cd content in the water system was 0.67 times that of the control group. The Cd2+ influx increased significantly. 4471 genes were up-regulated and 3230 genes were down-regulated significantly as duckweed treated with GO under Cd treatment. Moreover, phagosome pathway was downregulated, some key proteins: Stx7, Rab7 and Tubastatin B (TUBB) were significantly downregulated with GO addition under Cd stress. Scanning electron microscope (SEM) observation showed that GO and Cd were attached on the cell surface of duckweed as white crystal. GO could be applied in phytoremediation by duckweed of Cd in aquatic system.


Assuntos
Araceae/metabolismo , Cádmio/metabolismo , Grafite/toxicidade , Estresse Fisiológico , Absorção Fisiológica/efeitos dos fármacos , Araceae/efeitos dos fármacos , Araceae/crescimento & desenvolvimento , Araceae/ultraestrutura , Autofagia/efeitos dos fármacos , Autofagia/genética , Biodegradação Ambiental/efeitos dos fármacos , Permeabilidade da Membrana Celular/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ontologia Genética , Fagossomos/efeitos dos fármacos , Fagossomos/metabolismo , Fenótipo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Raízes de Plantas/ultraestrutura , Estresse Fisiológico/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade
11.
Sci Rep ; 10(1): 16401, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33009431

RESUMO

Aluminium (Al) toxicity limits crop productivity, particularly at low soil pH. Proline (Pro) plays a role in protecting plants against various abiotic stresses. Using the relatively Al-tolerant cereal rye (Secale cereale L.), we evaluated Pro metabolism in roots and shoots of two genotypes differing in Al tolerance, var. RioDeva (sensitive) and var. Beira (tolerant). Most enzyme activities and metabolites of Pro biosynthesis were analysed. Al induced increases in Pro levels in each genotype, but the mechanisms were different and were also different between roots and shoots. The Al-tolerant genotype accumulated highest Pro levels and this stronger increase was ascribed to simultaneous activation of the ornithine (Orn)-biosynthetic pathway and decrease in Pro oxidation. The Orn pathway was particularly enhanced in roots. Nitrate reductase (NR) activity, N levels, and N/C ratios demonstrate that N-metabolism is less inhibited in the Al-tolerant line. The correlation between Pro changes and differences in Al-sensitivity between these two genotypes, supports a role for Pro in Al tolerance. Our results suggest that differential responses in Pro biosynthesis may be linked to N-availability. Understanding the role of Pro in differences between genotypes in stress responses, could be valuable in plant selection and breeding for Al resistance.


Assuntos
Alumínio/toxicidade , Prolina/metabolismo , Secale/efeitos dos fármacos , Secale/metabolismo , Transdução de Sinais/efeitos dos fármacos , Adaptação Fisiológica/efeitos dos fármacos , Cruzamento/métodos , Genótipo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/genética , Folhas de Planta/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Secale/genética , Estresse Fisiológico/efeitos dos fármacos
12.
Ecotoxicol Environ Saf ; 205: 111298, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32950806

RESUMO

Mulberry (Morus atropurpurea) is an economically important woody tree and has great potential for the remediation of heavy metals. To investigate how cadmium accumulates and its detoxification in mulberry, we assessed the physiological and transcriptomic effects of cadmium contamination and as well as its chemical forms and subcellular distribution. Cadmium significantly inhibited mulberry plant growth and primarily accumulated in mulberry roots. Antioxidant enzymes were induced by cadmium in all tissues of mulberry. Subcellular fractionation analyses of cadmium indicated that the majority was compartmentalized in soluble fraction in roots while it mainly located in cell wall in leaves and stems. The greatest amount of the cadmium was integrated with proteins and pectates in all mulberry tissues. RNA-seq transcriptomic analyses of mulberry roots revealed that various metabolic pathways involved in cadmium stress response such as RNA regulation, hormone metabolism, and response to stress, secondary metabolism, as well as signaling, protein metabolism, transport, and cell-wall metabolism. These results will increase our understanding of the molecular mechanisms of cadmium detoxification in mulberry and provide new insights into engineering woody plants for phytoremediation.


Assuntos
Bioacumulação , Cádmio/toxicidade , Morus/efeitos dos fármacos , Poluentes do Solo/toxicidade , Estresse Fisiológico/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Biodegradação Ambiental , Cádmio/metabolismo , Perfilação da Expressão Gênica , Morus/crescimento & desenvolvimento , Morus/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Poluentes do Solo/metabolismo , Estresse Fisiológico/genética
13.
Ecotoxicol Environ Saf ; 203: 111007, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888586

RESUMO

Soil acidification is one of the crucial global environmental problems, affecting sustainable land use, crop yield, and ecosystem stability. Previous research reported the tolerance of crops to acid soil stress. However, the molecular response of woody plant to acid conditions remains largely unclear. Rhododendron L. is a widely distributed woody plant genus and prefers to grow in acidic soils. Herein, weighted gene coexpression network analysis was performed on R. protistum var. giganteum seedlings subjected to five pH treatments (3.5, 4.5, 5.5, 6.0, 7.0), and their ecophysiological characteristics were determined for the identification of their molecular responses to acidic environments. Through pairwise comparison, 855 differentially expressed genes (DEGs) associated with photosynthesis, cell wall, and phenylpropanoid metabolism were identified. Most of the DEGs related to photosynthesis and cell wall were up-regulated after pH 4.5 treatment. Results implied that the species improves its photosynthetic abilities and changes its cell wall characteristics to adapt to acidic conditions. Weighted gene co-expression network analyses showed that most of the hub genes were annotated to the biosynthetic pathways of ribosomal proteins and photosynthesis. Expression pattern analysis showed that genes encoding subunit ribosomal proteins decreased at pH 7.0 treatment, suggesting that pH 7.0 treatment led to cell injury in the seedlings. The species regulates protein synthesis in response to high pH stress (pH 7.0). The present study revealed the molecular response mechanism of woody plant R. protistum var. giganteum to acid environments. These findings can be useful in enriching current knowledge of how woody species adapt to soil acidification under global environmental changes.


Assuntos
Ácidos/farmacologia , Parede Celular/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Madeira/efeitos dos fármacos , Parede Celular/genética , Parede Celular/metabolismo , Perfilação da Expressão Gênica , Redes Reguladoras de Genes/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Fotossíntese/genética , Plântula/efeitos dos fármacos , Plântula/metabolismo , Solo/química , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genética , Madeira/genética , Madeira/metabolismo
14.
Am J Surg ; 220(5): 1312-1318, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32741547

RESUMO

INTRODUCTION: Propranolol has been shown to improve erythroid progenitor cell growth and anemia following trauma and this study sought to investigate the mechanisms involved by evaluating the effects of selective beta blockade. METHODS: Male Sprague-Dawley rats were subjected to lung contusion, hemorrhagic shock and chronic stress (LCHS/CS) ± daily selective beta-1, beta-2, or beta-3 blockade (B1B, B2B, B3B). Bone marrow cellularity and growth of erythroid progenitor colonies, hemoglobin, plasma granulocyte colony-stimulating factor (G-CSF), hematopoietic progenitor cell mobilization, and daily weight were assessed. RESULTS: Selective beta-2 and beta-3 blockade improved bone marrow cellularity, erythroid progenitor colony growth and hemoglobin levels, while decreasing plasma G-CSF, progenitor cell mobilization and weight loss following LCHS/CS. CONCLUSIONS: Attenuating the neuroendocrine stress response with the use of selective beta-2 and 3 adrenergic blockade may be an alternative to improve bone marrow erythroid function following trauma.


Assuntos
Antagonistas Adrenérgicos beta/farmacologia , Medula Óssea/efeitos dos fármacos , Contusões/tratamento farmacológico , Lesão Pulmonar/tratamento farmacológico , Propranolol/farmacologia , Choque Hemorrágico/tratamento farmacológico , Estresse Fisiológico/efeitos dos fármacos , Antagonistas Adrenérgicos beta/uso terapêutico , Animais , Biomarcadores/metabolismo , Medula Óssea/metabolismo , Medula Óssea/patologia , Medula Óssea/fisiopatologia , Contusões/fisiopatologia , Lesão Pulmonar/fisiopatologia , Masculino , Propranolol/uso terapêutico , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Choque Hemorrágico/fisiopatologia
15.
Ecotoxicol Environ Saf ; 205: 111167, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32827967

RESUMO

Contamination of agricultural fields with Cadmium (Cd) due to several agricultural practices is increasing worldwide. The rice plants can easily take up Cd and accumulate it into different parts, including the grains, posing a threat to human health even at low concentration exposure. Several phytohormones, including Salicylic acid (SA) have been investigated since long for its alleviating properties under various biotic and abiotic stress conditions. In the present study, 100 µM SA application to ameliorate 25 µM Cd stress was studied for 72 h in hydroponics in Oryza sativa cv. Bandana seedlings. Pot experiments were done with same treatment condition and plants were grown till maturity. SA application to Cd exposed rice seedlings alleviated the stress condition, which was established by several physiological, biochemical, histochemical and gene expression analysis. SA treatment to Cd stressed seedlings showed elevated photosynthetic pigment content, on-protein thiol content and relieved the Cd induced growth inhibition considerably. It lowered the accumulation of ROS like, O2- and H2O2 with a regulated antioxidative enzymatic activity. SA application in Cd exposed rice seedlings had upregulated expression of OsHMA3 and OsPCS1 whereasOsNRAMP2 gene was downregulated. Co-application of SA and Cd led to higher yield and improved agronomic traits in comparison to only Cd exposed plants under pot experimentation. Daily intake of Cd and Carcinogenic risk were also reduced by 99.75% and 99.99% respectively in the SA treated Cd stressed plants. SA positively affected the growth and tolerance of rice seedlings to Cd stress. Hence, SA addition to Cd contaminated soil can ensure rice cultivation without posing health risk to consumers.


Assuntos
Bioacumulação/efeitos dos fármacos , Cádmio/toxicidade , Grão Comestível/efeitos dos fármacos , Oryza/efeitos dos fármacos , Ácido Salicílico/farmacologia , Poluentes do Solo/toxicidade , Antioxidantes/metabolismo , Cádmio/metabolismo , Grão Comestível/metabolismo , Peróxido de Hidrogênio/metabolismo , Hidroponia , Oryza/metabolismo , Fotossíntese/efeitos dos fármacos , Plântula/efeitos dos fármacos , Plântula/metabolismo , Poluentes do Solo/metabolismo , Estresse Fisiológico/efeitos dos fármacos
16.
Biochim Biophys Acta Bioenerg ; 1861(12): 148290, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32828729

RESUMO

We hypothesized that NO• is generated in isolated cardiac mitochondria as the source for ONOO- production during oxidative stress. We monitored generation of ONOO- from guinea pig isolated cardiac mitochondria subjected to excess Ca2+ uptake before adding succinate and determined if ONOO- production was dependent on a nitric oxide synthase (NOS) located in cardiac mitochondria (mtNOS). Mitochondria were suspended in experimental buffer at pH 7.15, and treated with CaCl2 and then the complex II substrate Na-succinate, followed by menadione, a quinone redox cycler, to generate O2•-. L-tyrosine was added to the mitochondrial suspension where it is oxidized by ONOO- to form dityrosine (diTyr) in proportion to the ONOO- present. We found that exposing mitochondria to excess CaCl2 before succinate resulted in an increase in diTyr and amplex red fluorescence (H2O2) signals, indicating that mitochondrial oxidant stress, induced by elevated mtCa2+ and succinate, increased mitochondrial ONOO- production via NO• and O2•-. Changes in mitochondrial ONOO- production dependent on NOS were evidenced by using NOS inhibitors L-NAME/L-NNA, TEMPOL, a superoxide dismutase (SOD) mimetic, and PTIO, a potent global NO• scavenger. L-NAME and L-NNA decreased succinate and menadione-mediated ONOO- production, PTIO decreased production of ONOO-, and TEMPOL decreased ONOO- levels by converting more O2•- to H2O2. Electron microscopy showed immuno-gold labeled iNOS and nNOS in mitochondria isolated from cardiomyocytes and heart tissue. Western blots demonstrated iNOS and nNOS bands in total heart tissue, bands for both iNOS and nNOS in ß-tubulin-free non-purified (crude) mitochondrial preparations, and a prominent iNOS band, but no nNOS band, in purified (Golgi and ER-free) mitochondria. Prior treatment of guinea pigs with lipopolysacharride (LPS) enhanced expression of iNOS in liver mitochondria but not in heart mitochondria. Our results indicate that release of ONOO- into the buffer is dependent both on O2•- released from mitochondria and NO• derived from a mtCa2+-inducible nNOS isoform, possibly attached to mitochondria, and a mtNOS isoform like iNOS that is non-inducible.


Assuntos
Cálcio/farmacologia , Mitocôndrias Cardíacas/metabolismo , Óxido Nítrico/biossíntese , Estresse Oxidativo/efeitos dos fármacos , Ácido Peroxinitroso/metabolismo , Ácido Succínico/farmacologia , Animais , Transporte de Elétrons/efeitos dos fármacos , Depuradores de Radicais Livres/metabolismo , Cobaias , Peróxido de Hidrogênio/metabolismo , Isoenzimas/metabolismo , Isoenzimas/ultraestrutura , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias Cardíacas/efeitos dos fármacos , Mitocôndrias Cardíacas/ultraestrutura , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase/ultraestrutura , Espectrometria de Fluorescência , Estresse Fisiológico/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Fatores de Tempo
17.
PLoS One ; 15(8): e0234166, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32797098

RESUMO

Response to simultaneous stressors is an important facet of plant ecology and land management. In a greenhouse trial, we studied how eight plant species responded to single and combined effects of three soil concentrations of the phytotoxic munitions constituent RDX and two levels of water-resourcing. In an outdoor trial, we studied the effects of high RDX soil concentration and two levels of water-resourcing in three plant species. Multiple endpoints related to RDX fate, plant health, and plant survival were evaluated in both trials. Starting RDX concentration was the most frequent factor influencing all endpoints. Water-resourcing also had significant impacts, but in fewer cases. For most endpoints, significant interaction effects between RDX concentration and water-resourcing were observed for some species and treatments. Main and interaction effects were typically variable (significant in one treatment, but not in another; associated with increasing endpoint values for one treatment and/or with decreasing endpoint values in another). This complexity has implications for understanding how RDX and water-availability combine to impact plants, as well as for applications like phytoremediation. As an additional product of these greenhouse and outdoor trials, three plants native or naturalized within the southeastern United States were identified as promising species for further study as in situ phytoremediation resources. Plumbago auriculata exhibited relatively strong and markedly consistent among-treatment mean proportional reductions in soil RDX concentrations (112% and 2.5% of the means of corresponding values observed within other species). Likewise, across all treatments, Salvia coccinea exhibited distinctively low variance in mean leaf chlorophyll content index levels (6.5% of the means of corresponding values observed within other species). Both species also exhibited mean wilting and chlorosis levels that were 66% and 35%, and 67% and 84%, of corresponding values observed in all other plants, respectively. Ruellia caroliniensis exhibited at least 43% higher mean survival across all treatments than any other test species in outdoor trials, despite exhibiting similar RDX uptake and bioconcentration levels.


Assuntos
Substâncias Explosivas/toxicidade , Plantas/efeitos dos fármacos , Poluentes do Solo/toxicidade , Triazinas/toxicidade , Acanthaceae/efeitos dos fármacos , Acanthaceae/crescimento & desenvolvimento , Acanthaceae/fisiologia , Biodegradação Ambiental , Substâncias Explosivas/administração & dosagem , Substâncias Explosivas/farmacocinética , Instalações Militares , Desenvolvimento Vegetal/efeitos dos fármacos , Fenômenos Fisiológicos Vegetais/efeitos dos fármacos , Plumbaginaceae/efeitos dos fármacos , Plumbaginaceae/crescimento & desenvolvimento , Plumbaginaceae/fisiologia , Salvia/efeitos dos fármacos , Salvia/crescimento & desenvolvimento , Salvia/fisiologia , Poluentes do Solo/administração & dosagem , Poluentes do Solo/farmacocinética , Sudeste dos Estados Unidos , Estresse Fisiológico/efeitos dos fármacos , Triazinas/administração & dosagem , Poluentes Químicos da Água/administração & dosagem , Poluentes Químicos da Água/farmacocinética , Poluentes Químicos da Água/toxicidade , Recursos Hídricos
18.
PLoS One ; 15(8): e0237845, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32813721

RESUMO

Aluminum (Al3+) toxicity is one of the most important limitations to agricultural production worldwide. The overall response of plants to Al3+ stress has been documented, but the contribution of protein phosphorylation to Al3+ detoxicity and tolerance in plants is unclear. Using a combination of tandem mass tag (TMT) labeling, immobilized metal affinity chromatography (IMAC) enrichment and liquid chromatography-tandem mass spectrometry (LC-MS/MS), Al3+-induced phosphoproteomic changes in roots of Tamba black soybean (TBS) were investigated in this study. The Data collected in this study are available via ProteomeXchange with the identifier PXD019807. After the Al3+ treatment, 189 proteins harboring 278 phosphosites were significantly changed (fold change > 1.2 or < 0.83, p < 0.05), with 88 upregulated, 96 downregulated and 5 up-/downregulated. Enrichment and protein interaction analyses revealed that differentially phosphorylated proteins (DPPs) under the Al3+ treatment were mainly related to G-protein-mediated signaling, transcription and translation, transporters and carbohydrate metabolism. Particularly, DPPs associated with root growth inhibition or citric acid synthesis were identified. The results of this study provide novel insights into the molecular mechanisms of TBS post-translational modifications in response to Al3+ stress.


Assuntos
Alumínio/toxicidade , Fosfoproteínas/metabolismo , Proteínas de Plantas/metabolismo , Proteômica , Soja/metabolismo , Citratos/metabolismo , Fosforilação/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Biossíntese de Proteínas/efeitos dos fármacos , Mapas de Interação de Proteínas/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Soja/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Transcrição Genética/efeitos dos fármacos
19.
Psychopharmacology (Berl) ; 237(10): 3047-3056, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32601985

RESUMO

RATIONALE: Stress is associated with increased sensitivity to threat. Previous investigations examining how stress affects threat processing have largely focused on biomarker responses associated with either the sympathetic-nervous-system (SNS) or the hypothalamus-pituitary-adrenal (HPA) axis. OBJECTIVES: We pharmacologically suppressed activations of SNS, HPA, or both, prior to stress and investigated how each stress system modulates social threat assessment. METHODS: One hundred sixty-one healthy men and women were randomized in a between-subject design, to one of four pharmacological or placebo conditions: dexamethasone-placebo, placebo-propranolol, dexamethasone-propranolol, or placebo-placebo. Participants provided threat assessments for angry and neutral human faces on a baseline day, and immediately after stress induction on a testing day. RESULTS: With both systems responding normally to stress (placebo-placebo), threat assessment was higher for neutral faces compared with angry. Compared with placebo, SNS suppression resulted in increased threat assessment for angry faces. HPA suppression resulted in decreased threat assessment for neutral and angry faces. When both systems were suppressed, there was an increase in threat assessment for angry faces, and no difference from placebo for neutral. CONCLUSION: Our findings demonstrated that when intact, the biological stress systems adaptively support organisms during stress by focusing attention towards specific stimuli that are relevant to the threat. Dysregulations of the stress systems result in important system specific consequences on threat evaluation, such that suppression of either stress system alone resulted in reduced threat assessment for contextually relevant threatening stimuli, whereas when both systems were suppressed, individuals appear indiscriminately attentive to all potential threats in the environment, resulting in increased threat processing of both contextually relevant and irrelevant stimuli. Given that stress-related psychopathologies have been associated with dysregulations of the stress systems and biased responses to social threat, a systematic understanding of the mechanisms that underlie how stress systems modulate social threat assessment is needed, and can provide important insights into the cognitive processes that are involved in the development and maintenance of stress-related psychopathologies.


Assuntos
Estresse Fisiológico/fisiologia , Estresse Psicológico/metabolismo , Estresse Psicológico/psicologia , Adolescente , Antagonistas Adrenérgicos beta/administração & dosagem , Adulto , Ira/efeitos dos fármacos , Ira/fisiologia , Dexametasona/administração & dosagem , Feminino , Glucocorticoides/administração & dosagem , Humanos , Hidrocortisona/metabolismo , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/metabolismo , Masculino , Estimulação Luminosa/métodos , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/metabolismo , Propranolol/administração & dosagem , Saliva/efeitos dos fármacos , Saliva/metabolismo , Estresse Fisiológico/efeitos dos fármacos , Adulto Jovem
20.
BMC Evol Biol ; 20(1): 91, 2020 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-32727363

RESUMO

BACKGROUND: The SIAMESE (SIM) locus is a cell-cycle kinase inhibitor (CKI) gene that has to date been identified only in plants; it encodes a protein that promotes transformation from mitosis to endoreplication. Members of the SIAMESE-RELATED (SMR) family have similar functions, and some are related to cell-cycle responses and abiotic stresses. However, the functions of SMRs are poorly understood in maize (Zea mays L.). RESULTS: In the present study, 12 putative SMRs were identified throughout the entire genome of maize, and these were clustered into six groups together with the SMRs from seven other plant species. Members of the ZmSMR family were divided into four groups according to their protein sequences. Various cis-acting elements in the upstream sequences of ZmSMRs responded to abiotic stresses. Expression analyses revealed that all ZmSMRs were upregulated at 5, 20, 25, and 35 days after pollination. In addition, we found that ZmSMR9/11/12 may have regulated the initiation of endoreplication in endosperm central cells. Additionally, ZmSMR2/10 may have been primarily responsible for the endoreplication regulation of outer endosperm or aleurone cells. The relatively high expression levels of almost all ZmSMRs in the ears and tassels also implied that these genes may function in seed development. The effects of treatments with ABA, heat, cold, salt, and drought on maize seedlings and expression of ZmSMR genes suggested that ZmSMRs were strongly associated with response to abiotic stresses. CONCLUSION: The present study is the first to conduct a genome-wide analysis of members of the ZmSMR family by investigating their locations in chromosomes, identifying regulatory elements in their promoter regions, and examining motifs in their protein sequences. Expression analysis of different endosperm developmental periods, tissues, abiotic stresses, and hormonal treatments suggests that ZmSMR genes may function in endoreplication and regulate the development of reproductive organs. These results may provide valuable information for future studies of the functions of the SMR family in maize.


Assuntos
Evolução Molecular , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Família Multigênica , Zea mays/genética , Sequência de Aminoácidos , Sequência de Bases , Cromossomos de Plantas/genética , Sequência Conservada/genética , Endosperma/genética , Duplicação Gênica , Genes de Plantas , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Regiões Promotoras Genéticas/genética , Análise de Regressão , Especificidade da Espécie , Estresse Fisiológico/efeitos dos fármacos , Sintenia/genética
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