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2.
World J Microbiol Biotechnol ; 36(2): 23, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31965334

RESUMO

Arsenic naturally occurs in the earth's crust and can be introduced in the environment by human activities. Agricultural practices in arsenic-contaminated environments pose a threat to human health. The contamination of crops contributes to the metalloid's introduction in the food chain. This study aims to test the hypotheses that the inoculation of a hyperaccumulator rhizobacterial strain, Ochrobactrum tritici As5, to the rhizosphere of rice plants reduces the arsenic presence inside the tissue of the rice plants and reduces the inhibitory effect of the metalloid on the plant's growth parameters. Inoculation of the hyperaccumulating strain O. tritici As5 showed the lowest concentration of arsenic in the plant's tissue (2.6 fold lower than sterile plants), compared to the unmodified type O. tritici SCII24 and sterile rice plants. The inoculation of the type strain SCII24 also led to a decrease in arsenic concentration in the plant tissue compared with sterile plants (1.6 fold lower than sterile plants). The difference in arsenic presence in shoots was smaller among treatment groups than in the roots, showing a similar trend. The inoculation of the hyperaccumulator As5 strain alleviated some of the toxic effects of arsenic on shoot growth compared to inoculation of the unmodified type strain. All these findings together, contribute to our understanding of the interplay between arsenic pollution, plants and their rhizobacteria, especially the role of bioaccumulation of metal(oids) by rhizobacteria, and provide important information on the prevention of arsenic uptake by crops and the development of phytostabilizers.


Assuntos
Arsênico/análise , Ochrobactrum/crescimento & desenvolvimento , Oryza/microbiologia , Arsênico/toxicidade , Biodegradação Ambiental , Produtos Agrícolas/química , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/microbiologia , Ochrobactrum/metabolismo , Oryza/química , Oryza/crescimento & desenvolvimento , Brotos de Planta/química , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/microbiologia , Rizosfera , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
3.
Nat Commun ; 11(1): 76, 2020 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-31900388

RESUMO

In many plant species, roots maintain specific growth angles relative to the direction of gravity, known as gravitropic set point angles (GSAs). These contribute to the efficient acquisition of water and nutrients. AtLAZY1/LAZY1-LIKE (LZY) genes are involved in GSA control by regulating auxin flow toward the direction of gravity in Arabidopsis. Here, we demonstrate that RCC1-like domain (RLD) proteins, identified as LZY interactors, are essential regulators of polar auxin transport. We show that interaction of the CCL domain of LZY with the BRX domain of RLD is important for the recruitment of RLD from the cytoplasm to the plasma membrane by LZY. A structural analysis reveals the mode of the interaction as an intermolecular ß-sheet in addition to the structure of the BRX domain. Our results offer a molecular framework in which gravity signal first emerges as polarized LZY3 localization in gravity-sensing cells, followed by polar RLD1 localization and PIN3 relocalization to modulate auxin flow.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Transporte Biológico , Gravitropismo , Sensação Gravitacional , Ácidos Indolacéticos/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/fisiologia , Brotos de Planta , Ligação Proteica
4.
Chemosphere ; 242: 125168, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31678850

RESUMO

Plants have evolved effective strategies to cope with heavy metals Cd toxicity, but the regulatory mechanism underlying Cd tolerance and accumulation are still poorly understood. miR156 has been shown to be the master regulator of development and stress response in plants. However, whether miR156 is also involved in plant Cd stress response remains unknown. Here, we show that plants overexpressing miR156 (miR156OE) accumulated significantly less Cd in the shoot, and conferred enhanced tolerance to Cd stress. Plants with a knocked-down level of miR156 (MIM156) were sensitive to Cd stress, and accumulated significantly higher Cd. Under Cd stress, miR156OE had significantly longer primary root length, higher biomass and chlorophyll content, increased activities of antioxidative enzymes and lower levels of endogenous reactive oxygen species (ROS), while MIM156 had the opposite phenotype. To investigate the underlying mechanism of miR156-mediated Cd stress response in Arabidopsis, we profiled the expression of several Cd transporter genes. The expression of Cd uptake transporter of AtZIP1、AtZIP2 and vacuole segregated transporter AtABCC1 was significantly elevated in miR156OE, whereas it was significantly reduced in MIM156. MIM156 also led to an elevated level of AtHMA4 responsible for transporting Cd from the root to the shoot. Our results indicate that miR156 acts as a positive regulator of plant tolerance to Cd stress by modulating ROS levels and Cd uptake/transport genes expression. Therefore, our study adds a new layer of regulatory mechanism for Cd transport and tolerance in plants, and provides a perspective to regulate Cd transport artificially by modulating plant vegetative growth and development using miR156.


Assuntos
Adaptação Fisiológica/genética , Proteínas de Arabidopsis/genética , Arabidopsis/metabolismo , Bioacumulação , Cádmio/metabolismo , MicroRNAs/genética , Poluentes do Solo/metabolismo , Arabidopsis/genética , Transporte Biológico , Clorofila/metabolismo , Regulação da Expressão Gênica de Plantas , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Plantas Geneticamente Modificadas/genética , Espécies Reativas de Oxigênio/metabolismo
5.
J Sci Food Agric ; 100(4): 1702-1710, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31803935

RESUMO

BACKGROUND: The presence of insoluble calcium oxalate druse crystals (CaOx) in sweet potato (Ipomoea batatas) can negatively affect its nutritional quality. Photosynthesis, starch, and protein composition are linked with oxalate synthesis and tuber quality under water scarcity. Our main objective was the oxalate quantitation of sweet potato tubers and shoots and also to assess how drought changes their nutritional value. Eight sweet potato accessions from Madeira, the Canaries and Guinea-Bissau were analyzed for their response to drought stress. Tubers and shoots were analyzed for total (T-Ox), soluble (S-Ox) and insoluble (CaOx) oxalates, protein, chlorophyll content index (CCI), soluble starch, starch swelling power, and starch solubility in water. RESULTS: The S-Ox and CaOx content was higher in shoots. Six accessions were above maximum CaOx levels for raw consumption. Accessions with more favorable responses to drought had decreased CaOx with S-Ox increase content for osmoregulation. They also presented slightly decreased CCI and protein contents. These accessions also had an increased shoot starch content, for further tuber storage starch hydrolysis, and maintained the quality and functional properties of the tuber starch grain. Those with a less favorable response to drought had a higher T-Ox and CaOx content in both organs, hindering water absorption. They also had decreased protein and CCI, with a slight increase in tuber starch hydrolysis. CONCLUSION: Oxalate content was significantly related to carbohydrate metabolism, CCI, and protein synthesis. This study significantly contributed to the screening of the sweet potato stress response to drought, to adapt this crop to climatic change through breeding programs. © 2019 Society of Chemical Industry.


Assuntos
Ipomoea batatas/metabolismo , Oxalatos/química , Tubérculos/química , Água/metabolismo , Metabolismo dos Carboidratos , Secas , Ipomoea batatas/química , Oxalatos/metabolismo , Fotossíntese , Brotos de Planta/química , Brotos de Planta/metabolismo , Tubérculos/metabolismo , Amido/análise , Amido/metabolismo , Água/análise
6.
Int J Phytoremediation ; 22(2): 134-139, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31379204

RESUMO

In this study, different soil Pb concentrations [24 (control), 80, 136, 362, and 1150 mg kg-1] were used to analyze the tolerance threshold and accumulation potential of Brassica juncea L. in a pot experiment under greenhouse conditions. In addition to growth and Pb accumulation, the following contamination indices were calculated: transfer coefficient (TC), translocation factor (TF), and tolerance index (TI). Growth and Pb accumulation were determined at 60 days after emergence. The Pb concentrations were determined using the flame atomic absorption spectrometry (FAAS). The plant height was affected by soil Pb contamination, and it decreased from 1.37 to 0.83 m when the soil Pb concentration increased from 24 (control) to 1150 mg kg-1, respectively. The Pb concentration in the shoots and roots increased as the Pb concentration in the soil increased, reaching 94 mg kg-1 in shoots and 783 mg kg-1 in roots when was grown under 1150 mg kg-1 of Pb. TF was <1 at all levels of contamination. The TI values suggested that B. juncea presented Pb tolerance in Pb contaminated soils. Our findings indicate that B. juncea has the potential to accumulate Pb in soil under tropical conditions.


Assuntos
Mostardeira , Poluentes do Solo , Biodegradação Ambiental , Chumbo , Raízes de Plantas , Brotos de Planta
7.
J Sci Food Agric ; 100(4): 1505-1514, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31756273

RESUMO

BACKGROUND: Greater proportions of purple tea buds and leaves usually appear in the summer, which seriously affects the color and taste quality of green tea products, yet the metabolism of purple tea shoots in summer remains unclear. Here, the metabolomic profiles and gene expression of related flavonoid metabolic pathways in the purple and normal green shoots of 'Longjing 43', and the quality of green tea made with these two phenotypes, were analyzed and compared. RESULTS: Differential metabolites identified using high-performance liquid chromatography-Orbitrap/mass spectrometry indicated that anthocyanin biosynthesis in purple leaves was enriched, with higher levels of anthocyanidins (delphinidin-hexose-coumaroyl showed the greatest increase), proanthocyanidins (oligomers of catechins) and kaempferol glycoside. Expression patterns of the genes ANR, ANS, FLS, LAR, C4H, PAL, CHI, CHS and DFR revealed that the metabolism of anthocyanin is positively regulated by high temperature and/or light levels in summer. Gas chromatography-mass spectrometry results showed that, in purple tea shoots, the metabolism of carbohydrates was enriched whereas that of amino acids was diminished, while their mannose, fructose, d-galactose, sorbose and d-glucose contents were more than double those found in green leaves. A sensory evaluation confirmed that a greater quantity of purple shoots had a greater negative impact on green tea quality because of a bitter taste and dark color (leaves and infusions were tested). CONCLUSIONS: These results highlight the need for and possibility of improving commercial tea quality via cultivation that controls the temperature or light of tea gardens during the summer. © 2019 Society of Chemical Industry.


Assuntos
Antocianinas/biossíntese , Camellia sinensis/metabolismo , Brotos de Planta/metabolismo , Camellia sinensis/química , Camellia sinensis/genética , Camellia sinensis/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Folhas de Planta/química , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Brotos de Planta/química , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Estações do Ano
8.
Chemosphere ; 240: 124907, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31550592

RESUMO

Deciphering the mechanism of Cd accumulation in crops is imperative for minimizing soil-to-plant transfer of Cd to improve safe food production. Hydroponic experiments were performed examining Cd accumulation, growth performance and protein characteristics of two rice genotypes, Xiushui817 and Zheda821, with low and high grain Cd accumulation, respectively, under Cd stress and in the presence of Si. Xiushui817 had lower root-to-shoot Cd translocation and was more sensitive to Cd stress than Zheda821. Si reduced the shoot Cd content in both genotypes but more efficacy in Zheda821. Tandem mass tags (TMT)-based proteomic analysis identified 25 proteins associated with low grain Cd accumulation, including vacuolar H+-pyrophosphatase 1 (OVP1) that was up-regulated after Si addition in Zheda821. The sequence comparison of OVP1 showed one nucleotide difference in Xiushui817 relative to Zheda821 resulting in one amino acid. Overexpression of OVP1 reduced shoot Cd concentration and improved the growth of rice compared with WT under both control and Cd treatment. The results highlight the significant roles of OVP1 in both Cd accumulation and the Si-induced Cd reduction in rice. Our findings provide valuable insights into the molecular mechanism of low Cd accumulation and Si-induced decrease in Cd accumulation in rice. OVP1 could be used for transgenic overexpression in rice or other cereals for safe food production.


Assuntos
Cádmio/farmacocinética , Oryza/efeitos dos fármacos , Proteínas de Plantas/metabolismo , Pirofosfatases/metabolismo , Silício/farmacologia , Cádmio/toxicidade , Regulação da Expressão Gênica de Plantas , Genótipo , Hidroponia , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/genética , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/metabolismo , Plantas Geneticamente Modificadas , Proteômica/métodos , Pirofosfatases/genética , Poluentes do Solo/farmacocinética
9.
Chemosphere ; 240: 124916, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31563104

RESUMO

Cadmium contamination in greenhouse vegetable fields greatly limited the sustainable production especially of leafy vegetables. Hydroxyapatite (HAP), as a common soil amendment, has been widely used in the remediation of Cd-contaminated soils, while its remediation efficiency greatly depends on its particle sizes. In this study, a rhizobag pot experiment was conducted to investigate the effects of HAP (<60 nm, <12 µm and <80 µm) on bioavailability of Cd to celery grown in acidic and slightly Cd-contaminated greenhouse soil. The results suggested that HAP with the largest particle size (<80 µm) had the best effectiveness in reducing Cd uptake especially by the edible part of celery. Specifically, the increase in HAP (<80 µm) addition from 0.5% to 3% prominently reduced Cd concentrations in celery shoot by 19.6%-76.8% as compared with the untreated group. Also, adding HAP (<80 µm) especially at 3% significantly decreased translocation factor (TF) of Cd from celery root to shoot by 30.6% and reduced bioconcentration factor (BCF) of Cd from rhizosphere soil to celery shoot by 76.4%. These were predominantly associated with the significantly increased soil pH and the subsequently decreased soil CaCl2-Cd concentration after adding HAP (<80 µm). Overall, although rhizosphere soil pH was the key factor in controlling Cd uptake by edible celery and regulating BCF and TF of Cd, insignificant root-induced acidification had limited effect on the immobilization efficiency of Cd by HAP (<80 µm). In conclusion, HAP (<80 µm) has good potential for the remediation of Cd-contaminated greenhouse soils.


Assuntos
Apium/efeitos dos fármacos , Apium/metabolismo , Cádmio/farmacocinética , Durapatita/farmacologia , Poluentes do Solo/farmacocinética , Solo/química , Apium/crescimento & desenvolvimento , Biodegradação Ambiental , Disponibilidade Biológica , Cádmio/análise , Durapatita/química , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/metabolismo , Rizosfera , Poluentes do Solo/análise
10.
Ecotoxicol Environ Saf ; 188: 109858, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31706236

RESUMO

Cultivar-dependent cadmium (Cd) accumulation was principal in developing Cd-pollution safe cultivars (PSCs). Proteins related to different Cd accumulations of the low-Cd-accumulating (SJ19) and high-Cd-accumulating (CX4) cultivars were investigated by iTRAQ analysis. Higher Cd bioaccumulation factors and translocation factor in CX4 than in SJ19 were consistent with the cultivar-dependent Cd accumulations. The Cd uptake was promoted in CX4 due to its higher expression of Cd-binding proteins and the lower expression of Cd-efflux proteins in roots. What's more, significantly elevated thiol groups (PC2 and PC3) in CX4 under Cd stress might contribute to the high Cd accumulation in roots and the root-to-shoot translocation of Cd-PC complex. Up-regulated proteins involved in cellulose biosynthesis and pectin de-esterification in SJ19 enhanced the Cd sequestration of root cell walls, which was considered as the predominant strategy for reducing Cd accumulation in shoots. The present study provided novel insights in the cultivar-dependent Cd accumulation in shoots of B. parachinensis.


Assuntos
Brassica/metabolismo , Cádmio/metabolismo , Proteínas de Plantas/metabolismo , Poluentes do Solo/metabolismo , Transporte Biológico , Brassica/genética , Celulose/metabolismo , Pectinas/metabolismo , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Proteômica , Reagentes de Sulfidrila/metabolismo
11.
Chemosphere ; 239: 124760, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31518923

RESUMO

Plant growth and yield are adversely affected by the uptake of toxic hexavalent chromium (Cr(VI)) from soil. The present study describes a facile technique to minimize the uptake of Cr(VI) by chickpea (Cicer arietinum) plant from soil using microporous activated carbon microfiber (ACF). Simultaneously, nano-sized carbon nanofibers (CNFs), grown over the ACF substrate, are used as an efficient carrier of the Cu micronutrient from soil to root, shoot and leaf of the plants. Adsorption, seed germination and plant growth experiments are performed in Cr-stressed medium. The ACF, used as the adsorbent for Cr(VI) in metal-stressed soil (100 mg Cr kg-1 of soil) shows the metal loading of ∼23 mg g-1. Cr(VI) up to 50 mg L-1 concentration causes no stress during germination of chickpea seeds in Murashige and Skoog (MS) medium. A dose of 500 mg-mixture (treatment) per kg-soil increases root and shoot lengths by 52 and 11%, respectively than the control, during plant growth in the metal-stressed soil, attributed to an effective translocation of Cu-CNF through plant cells. Whereas Cr uptake by plant decrease to ∼46%, Cu uptake increase up to ∼120% in comparison to control by the mixture treatment. Protein and chlorophyll contents also significantly increased (*p < 0.05) with the application of treatment. The data clearly show that the mixture of ACF and Cu-CNF can be successfully used for the simultaneous scavenging of Cr(VI) from soil by adsorption over ACF and increased uptake of Cu by plants using the CNFs as the micronutrient carrier.


Assuntos
Cromo/farmacocinética , Cicer/crescimento & desenvolvimento , Nanofibras/química , Poluentes do Solo/farmacocinética , Adsorção , Carvão Vegetal/química , Clorofila/metabolismo , Cromo/isolamento & purificação , Cicer/efeitos dos fármacos , Cicer/metabolismo , Cobre/farmacocinética , Recuperação e Remediação Ambiental/métodos , Germinação , Folhas de Planta , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Solo/química , Poluentes do Solo/isolamento & purificação
12.
Food Chem ; 310: 125925, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31865174

RESUMO

In this work, water-insoluble bamboo shoot dietary fiber (BSDF) was prepared, and used as plant food particle stabilizer for oil-in-water (O/W) Pickering emulsions. The obtained plant food particle had novel emulsification ability, the prepared emulsions were stable against coalescence for at least 4 weeks and also insensitive to pH, ionic strength and pasteurization conditions. The BSDF suspensions and BSDF-stabilized O/W emulsions both exhibited shear-thinning behaviors; moreover, both viscosity and module were increased with the increase of BSDF contents. The surface coverage of emulsions was positively correlated with the content of BSDF suspensions. It indicated that the dietary fibers from bamboo shoot had a soft nature and suitable shape to produce stable Pickering emulsions, which could be used as food-grade particles for applications of food and cosmetics industries.


Assuntos
Fibras na Dieta , Emulsões/química , Nanofibras/química , Sasa/química , Celulose/química , Concentração de Íons de Hidrogênio , Microscopia de Força Atômica , Concentração Osmolar , Tamanho da Partícula , Brotos de Planta/química , Solubilidade , Temperatura Ambiente , Viscosidade , Água/química , Difração de Raios X
13.
World J Microbiol Biotechnol ; 35(12): 195, 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31784916

RESUMO

The search for effective plant-growth-promoting strains of rhizospheric bacteria that would ensure the resistance of plant-microbial associations to environmental stressors is essential for the design of environmentally friendly agrobiotechnologies. We investigated the interaction of potato (cv. Nevsky) microplants with the plant-growth-promoting bacteria Azospirillum brasilense Sp245 and Ochrobactrum cytisi IPA7.2 under osmotic stress in vitro. The bacteria improved the physiological and biochemical variables of the microplants, significantly increasing shoot length and root number (1.3-fold, on average). Inoculation also led a more effective recovery of the plants after stress. During repair, inoculation contributed to a decreased leaf content of malonic dialdehyde. With A. brasilense Sp245, the decrease was 1.75-fold; with O. cytisi IPA7.2, it was 1.4-fold. During repair, the shoot length, node number, and root number of the inoculated plants were greater than the control values by an average of 1.3-fold with A. brasilense Sp245 and by an average of 1.6-fold with O. cytisi IPA7.2. O. cytisi IPA7.2, previously isolated from the potato rhizosphere, protected the physiological and biochemical processes in the plants under stress and repair better than did A. brasilense Sp245. Specifically, root weight increased fivefold during repair, as compared to the noninoculated plants, while chlorophyll a content remained at the level found in the nonstressed controls. The results indicate that these bacteria can be used as components of biofertilizers. A. brasilense Sp245 has favorable prospects for use in temperate latitudes, whereas O. cytisi IPA7.2 can be successfully used in saline and drought-stressed environments.


Assuntos
Interações entre Hospedeiro e Microrganismos/fisiologia , Pressão Osmótica , Desenvolvimento Vegetal , Solanum tuberosum/microbiologia , Estresse Fisiológico/fisiologia , Azospirillum brasilense/fisiologia , Clorofila A , Contagem de Colônia Microbiana , Secas , Malonatos , Ochrobactrum/fisiologia , Folhas de Planta , Raízes de Plantas/microbiologia , Brotos de Planta , Rizosfera
14.
PLoS Genet ; 15(12): e1008563, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31869326

RESUMO

The unfolded protein response (UPR) is required for protein homeostasis in the endoplasmic reticulum (ER) when plants are challenged by adverse environmental conditions. Inositol-requiring enzyme 1 (IRE1), the bifunctional protein kinase / ribonuclease, is an important UPR regulator in plants mediating cytoplasmic splicing of the mRNA encoding the transcription factor bZIP60. This activates the UPR signaling pathway and regulates canonical UPR genes. However, how the protein activity of IRE1 is controlled during plant growth and development is largely unknown. In the present study, we demonstrate that the nuclear and Golgi-localized protein BLISTER (BLI) negatively controls the activity of IRE1A/IRE1B under normal growth condition in Arabidopsis. Loss-of-function mutation of BLI results in chronic up-regulation of a set of both canonical UPR genes and non-canonical UPR downstream genes, leading to cell death and growth retardation. Genetic analysis indicates that BLI-regulated vegetative growth phenotype is dependent on IRE1A/IRE1B but not their canonical splicing target bZIP60. Genetic complementation with mutation analysis suggests that the D570/K572 residues in the ATP-binding pocket and N780 residue in the RNase domain of IRE1A are required for the activation of canonical UPR gene expression, in contrast, the D570/K572 residues and D590 residue in the protein kinase domain of IRE1A are important for the induction of non-canonical UPR downstream genes in the BLI mutant background, which correlates with the shoot growth phenotype. Hence, our results reveal the important role of IRE1A in plant growth and development, and BLI negatively controls IRE1A's function under normal growth condition in plants.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Proteínas Quinases/metabolismo , Processamento Alternativo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Fatores de Transcrição de Zíper de Leucina Básica/genética , Estresse do Retículo Endoplasmático , Regulação da Expressão Gênica de Plantas , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Resposta a Proteínas não Dobradas
15.
World J Microbiol Biotechnol ; 35(12): 188, 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31741120

RESUMO

Soil contamination due to cadmium (Cd) is a ubiquitous environmental problem for which inexpensive remediation alternatives are required. Phytoaccumulation, the use of plants to extract and accumulate heavy metals from the contaminated environment, is such an alternative. In this study, we aimed at establishing effective plant-bacteria interplay between Brachiaria mutica and Cd-resistant endophytic bacteria eventually leading to improved phytoremediation. B. mutica was grown in a Cd-contaminated soil and inoculated with three Cd-tolerant endophytic bacteria individually as well as in combination. Plant physiological parameters, biomass production, bacterial colonization, and Cd-accumulation were observed at four different Cd exposures, i.e., 100, 200, 400 and 1000 mg kg-1 of soil. The combined application of endophytic bacteria was more effective as compared to their individual applications at all concentrations. Nevertheless, highest performance of consortium was seen at 100 mg Cd kg-1 of soil, i.e., root length was enhanced by 46%, shoot length by 62%, chlorophyll content by 40%, and dry biomass by 64%; which was reduced with the increase in Cd concentration. The bacterial population was highest in the root interior followed by rhizosphere and shoot interior. Concomitantly, plants inoculated with bacterial consortium displayed more Cd-accumulation in the roots (95%), shoots (55%), and leaves (44%). Higher values of BCFroot (> 1), and lower values for BCFshoot and TF (< 1) indicates capability of B. mutica to accumulate high amounts of Cd in the roots as compared to the aerial parts. The present study concludes that plant-endophyte interplay could be a sustainable and effective strategy for Cd removal from the contaminated soils.


Assuntos
Brachiaria/metabolismo , Brachiaria/microbiologia , Cádmio/metabolismo , Endófitos/fisiologia , Bactérias/metabolismo , Biodegradação Ambiental , Biomassa , Brachiaria/efeitos dos fármacos , Brachiaria/crescimento & desenvolvimento , Cádmio/análise , Cádmio/farmacologia , Produtos Agrícolas , Metais Pesados , Folhas de Planta/metabolismo , Raízes de Plantas/microbiologia , Brotos de Planta/metabolismo , Brotos de Planta/microbiologia , Rizosfera , Solo/química , Microbiologia do Solo , Poluentes do Solo
16.
J Chem Ecol ; 45(11-12): 946-958, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31755018

RESUMO

There are contrasting hypotheses regarding the role of plant volatiles in host plant location. We used the grape berry moth (GBM; Paralobesia viteana)-grape plant (Vitis spp.) complex as a model for studying the proximate mechanisms of long distance olfactory-mediated, host-plant location and selection by a specialist phytophagous insect. We used flight tunnel assays to observe GBM female in-flight responses to host (V. riparia) and non-host (apple, Malus domestica; and gray dogwood, Cornus racimosa,) odor sources in the form of plant shoots, extracts of shoots, and synthetic blends. Gas chromatography-electroantennographic detection and gas chromatography/mass spectrometry analyses were used to identify antennal-active volatile compounds. All antennal-active compounds found in grape shoots were also present in dogwood and apple shoots. Female GBM flew upwind to host and non-host extracts and synthetic blends at similar levels, suggesting discrimination is not occurring at long distance from the plant. Further, females did not land on sources releasing plant extracts and synthetic blends, suggesting not all landing cues were present. Additionally, mated and unmated moths displayed similar levels of upwind flight responses to all odor sources, supporting the idea that plant volatiles are not functioning solely as ovipositional cues. The results of this study support a hypothesis that GBM females are using volatile blends to locate a favorable habitat rather than a specific host plant, and that discrimination is occurring within the habitat, or even post-landing.


Assuntos
Mariposas/fisiologia , Oviposição/efeitos dos fármacos , Extratos Vegetais/química , Vitis/química , Compostos Orgânicos Voláteis/química , Animais , Comportamento Animal , Cornus/química , Feminino , Cromatografia Gasosa-Espectrometria de Massas/métodos , Especificidade de Hospedeiro , Interações Hospedeiro-Parasita , Controle de Insetos/métodos , Malus/química , Odorantes/análise , Brotos de Planta/química , Olfato , Vitis/parasitologia , Compostos Orgânicos Voláteis/metabolismo
17.
BMC Plant Biol ; 19(1): 505, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31744478

RESUMO

BACKGROUND: Ramet propagation in strawberry (Fragaria × ananassa) is the most effective way in production. However, the lack of systematically phenotypic observations and high-throughput methods limits our ability to analyze the key factors regulating the heterogeneity in strawberry stolon buds. RESULTS: From observation, we found that the axillary bud located in the first node quickly stepped into dormancy (DSB), after several bract and leaf buds were differentiated. The stolon apical meristem (SAM) degenerated as the new ramet leaf buds (RLB), and the new active axillary stolon buds (ASB) differentiated continually after the differentiation of the first leaf. Using the tandem mass tags (TMT) labeling method, a total of 7271 strawberry proteins were identified. Between ASB and DSB, the spliceosome DEPs, such as Ser/Arg-rich (SR) and heterogeneous nuclear ribonucleoprotein particle (hnRNP), showed the highest enrichment and high PPI connectivity. This indicated that the differences in DEPs (e.g., SF-3A and PK) at the transcriptional level may be causing the differences between the physiological statuses of ASB and DSB. As expected, the photosynthetic pre-form RLB mainly differentiated from ASB and DSB judging by the DEP enrichment of photosynthesis. However, there are still other specialized features of DEPs between RLB and DSB and between ASB and DSB. The DEPs relative to DNA duplication [e.g., minichromosome maintenance protein (MCM 2, 3, 4, 7)], provide a strong hint of functional gene duplication leading the bud heterogeneity between RLB and DSB. In addition, the top fold change DEP of LSH 10-like might be involved in the degeneration of SAM into RLBs, based on its significant function in modulating the plant shoot initiation. As for RLB/ASB, the phenylpropanoid biosynthesis pathway probably regulates the ramet axillary bud specialization, and further promotes the differentiation of xylem when ASB develops into a new stolon [e.g., cinnamyl alcohol dehydrogenase 1 (CAD1) and phenylalanine ammonia-lyase 1 (PAL1)]. CONCLUSIONS: By using phenotypic observation combined with proteomic networks with different types of strawberry stolon buds, the definite dormancy phase of DSB was identified, and the biological pathways and gene networks that might be responsible for heterogeneity among different stolon buds in strawberry were also revealed.


Assuntos
Fragaria/fisiologia , Proteínas de Plantas/metabolismo , Proteômica , Cromatografia Líquida , Biologia Computacional , Fragaria/genética , Fragaria/crescimento & desenvolvimento , Meristema/genética , Meristema/crescimento & desenvolvimento , Meristema/fisiologia , Fenótipo , Dormência de Plantas , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/fisiologia , Proteínas de Plantas/genética , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/fisiologia , Mapas de Interação de Proteínas , Espectrometria de Massas em Tandem
18.
Fitoterapia ; 139: 104402, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31672661

RESUMO

Rhododendron tomentosum (Ledum palustre) is an aromatic plant traditionally used for alleviating rheumatic complaints which makes it a potential candidate for a natural drug in rheumatoid arthritis (RA) treatment. However, the effects of plants' volatiles on apoptosis of synovial fibroblasts and infiltrating leucocytes of RA synovia, have not been reported. Volatile fraction of R. tomentosum is chemically variable and chemotypes of the plants need to be defined if the oil is to be used for therapeutic purposes. In the presented work, cluster analysis of literature data enabled to define 10 chemotypes of the plant. The volatile fractions of known composition were then tested for bioactivity using a RA-specific in vitro models. Essential oils of two wild types (γ-terpineol and palustrol/ledol type) and one in vitro chemotype (ledene oxide type) were obtained by hydrodistillation and their bioactivity was tested in two in vitro models: I - peripheral blood lymphocytes of healthy volunteers and II - synoviocytes and immune cells isolated from synovia of RA patients. The influence of oils on blood lymphocytes' proliferation and apoptosis rates of synovia-derived cells was determined by flow cytometry. Dose-dependent inhibitory effect of the serial dilutions of R. tomentosum oils on proliferation rates of blood lymphocytes was found. At 1:400 dilutions, all the tested oils increased the number of necrotic cells in synovial fibroblasts from RA synovia. Additionally, increased proportions of late apoptotic cells were observed in leucocyte populations subjected to oils at 1:400 dilution.


Assuntos
Apoptose , Ledum/química , Linfócitos/efeitos dos fármacos , Óleos Voláteis/farmacologia , Óleos Vegetais/farmacologia , Sinoviócitos/efeitos dos fármacos , Adulto , Artrite Reumatoide , Proliferação de Células/efeitos dos fármacos , Feminino , Finlândia , Humanos , Pessoa de Meia-Idade , Estrutura Molecular , Brotos de Planta/química , Polônia
19.
Ecotoxicol Environ Saf ; 186: 109795, 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31648160

RESUMO

Excessive cadmium (Cd) in rice grains is of great concern worldwide, particularly in southern China where heavy metal pollution in the soil is widespread. Much work has been done regarding the key genes responsible for Cd absorption, transport, and accumulation in rice, but little is known about the differences of Cd accumulation between indica and japonica rice cultivars during the reproductive stage. Furthermore, physiological parameters, such as nonstructural carbohydrate content, involved in Cd accumulation have not been fully elucidated. We studied several indica and japonica cultivars under three different Cd treatment levels and harvested them at different periods after heading. Differences in Cd accumulation between subspecies mainly were generated during the reproductive stage. An increase in the Cd pollution level caused the average absorption rate of Cd in the aerial parts of the indica cultivars in the reproductive stage to be 6.17, 4.52, and 3.89 times greater than that of the japonica cultivars across the three Cd treatments. The contribution of Cd absorption by shoots to Cd accumulation at the pre- or postheading stages was 33.8% and 66.2% in indica, and 44.9% and 55.1% in japonica. We found a significant negative correlation between Cd content in the rice grains and the content of nonstructural carbohydrates in the sheath (P < 0.05). Cd translocation from sheath to grain occurred along with sugar transfer in the indica cultivars. The Cd content of the indica cultivar grain was 1.84-4.14 times higher than that of the japonica cultivars (P < 0.05). The japonica cultivars thus met the cereal Cd limits of China (0.2 mg kg-1) under low and moderate soil Cd pollution. These findings are helpful for the selection of proper cultivars and field management practices to alleviate Cd exposure risk in rice production.


Assuntos
Cádmio/metabolismo , Oryza/classificação , Oryza/metabolismo , Poluentes do Solo/metabolismo , China , Grão Comestível/genética , Grão Comestível/metabolismo , Metais Pesados/análise , Oryza/genética , Brotos de Planta/genética , Brotos de Planta/metabolismo , Especificidade da Espécie , Açúcares/metabolismo
20.
BMC Genomics ; 20(1): 758, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31640549

RESUMO

BACKGROUND: The mesocotyl connects the coleoptilar node and the basal part of the seminal root of maize (Zea mays) seedling. The mesocotyl pushes the shoot of the seedling out of the soil during seed germination; thus, its growth is highly related to deep-sowing tolerance. Although many studies on the maize mesocotyl have been carried out at physiological and molecular levels, the proteomic changes associated with cellular and physiological activities during mesocotyl growth are still unknown. RESULTS: In the present study, the maize hybrid Zhengdan 958 was used to study mesocotyl growth and accompanying protein changes. The dark-grown etiolated mesocotyls exhibited a slow-fast-slow feature, with significant changes in the levels of indole-3-acetic acid (IAA) and cellulose and the activity of peroxidase (POD). In particular, POD activity increased with mesocotyl growth, showing higher activity at the mature (lower) end of the mesocotyl. For the proteomic analysis, soluble proteins were extracted from etiolated mesocotyls dark-grown for 48 h, 84 h, and 132 h, corresponding to the initial, rapid, and slow growth periods, respectively, and subjected to separation by two-dimensional gel electrophoresis (2-DE). As a result, 88 differentially abundant proteins (DAPs) were identified using MALDI-TOF-TOF analysis. At 48 h, most DAPs were stress proteins, heat shock proteins and storage proteins; at 84 h, oxidation/reduction proteins, carbohydrate biogenesis-related proteins and cytoskeleton-related proteins were highly accumulated; at 132 h, the most striking DAPs were those involved in the synthesis and modification of the cell wall and the biogenesis of carbohydrates. Gene ontology (GO) analysis showed that changes in the abundance and proportion of DAPs were consistent with cellular and physiological activities and biological processes during mesocotyl growth. The accumulation of nine DAPs of interest was verified by immunoblotting and RT-qPCR. CONCLUSIONS: The present study revealed that the protein patterns in 2-D gels differed greatly with mesocotyl growth. At different growth periods, a specific set of DAPs participate in various biological processes and underlie the cellular and physiological activities of the mesocotyl. These results contributed to the understanding of mesocotyl growth and the cultivation of maize lines with deep-sowing tolerance.


Assuntos
Proteínas de Plantas/metabolismo , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Zea mays , Agricultura , Celulose/metabolismo , Eletroforese em Gel Bidimensional , Estiolamento , Ácidos Indolacéticos/metabolismo , Peroxidases/metabolismo , Proteínas de Plantas/genética , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Proteômica , RNA Mensageiro/metabolismo , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo
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