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1.
Sci China Life Sci ; 2020 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-32737853

RESUMO

Cytoskeletal proteins are susceptible to glutathionylation under oxidizing conditions, and oxidative damage has been implicated in several neurodegenerative diseases. End-binding protein 1 (EB1) is a master regulator of microtubule plus-end tracking proteins (+TIPs) and is critically involved in the control of microtubule dynamics and cellular processes. However, the impact of glutathionylation on EB1 functions remains unknown. Here we reveal that glutathionylation is important for controlling EB1 activity and protecting EB1 from irreversible oxidation. In vitro biochemical and cellular assays reveal that EB1 is glutathionylated. Diamide, a mild oxidizing reagent, reduces EB1 comet number and length in cells, indicating the impairment of microtubule dynamics. Three cysteine residues of EB1 are glutathionylated, with mutations of these three cysteines to serines attenuating microtubule dynamics but buffering diamide-induced decrease in microtubule dynamics. In addition, glutaredoxin 1 (Grx1) deglutathionylates EB1, and Grx1 depletion suppresses microtubule dynamics and leads to defects in cell division orientation and cell migration, suggesting a critical role of Grx1-mediated deglutathionylation in maintaining EB1 activity. Collectively, these data reveal that EB1 glutathionylation is an important protective mechanism for the regulation of microtubule dynamics and microtubule-based cellular activities.

2.
Sci China Life Sci ; 63(5): 635-674, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32246404

RESUMO

Abiotic stresses and soil nutrient limitations are major environmental conditions that reduce plant growth, productivity and quality. Plants have evolved mechanisms to perceive these environmental challenges, transmit the stress signals within cells as well as between cells and tissues, and make appropriate adjustments in their growth and development in order to survive and reproduce. In recent years, significant progress has been made on many fronts of the stress signaling research, particularly in understanding the downstream signaling events that culminate at the activation of stress- and nutrient limitation-responsive genes, cellular ion homeostasis, and growth adjustment. However, the revelation of the early events of stress signaling, particularly the identification of primary stress sensors, still lags behind. In this review, we summarize recent work on the genetic and molecular mechanisms of plant abiotic stress and nutrient limitation sensing and signaling and discuss new directions for future studies.


Assuntos
Plantas/genética , Plantas/metabolismo , Solo/química , Estresse Fisiológico/fisiologia , Canais de Cálcio/metabolismo , Regulação da Expressão Gênica de Plantas , Metais Pesados/metabolismo , Fosforilação , Desenvolvimento Vegetal/genética , Proteínas de Plantas/metabolismo , Transdução de Sinais , Estresse Fisiológico/genética , Fatores de Transcrição/metabolismo
3.
Environ Sci Pollut Res Int ; 27(16): 19688-19702, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32219659

RESUMO

Heavy metals (Sc, Cr, Co, Ni, Cu, Ga, Ge, Nb, Mo, Cd, In, Hf, Ta, W, Tl, Pb, Bi, Th, and U) in the surface sediments of the Ganges-Brahmaputra-Meghna (GBM) river system of the Bengal Basin (BB) were measured to evaluate the heavy metal contamination and anthropogenic influence. The average concentration levels of most of the heavy metals (except Mo and Tl) were above the average crustal and shale values. Contamination indices, including the contamination factor, pollution load index, enrichment factor, and geo-accumulation index, and multivariate statistical analyses indicated that the GBM is slightly polluted by heavy metals with some considerable pollution from Bi, Th, Ta, Cd, Nb, Pb, In, and U. Among the four individual rivers, the Brahmaputra River and Ganges-Brahmaputra (GB) confluence river sediments contain higher heavy metal concentrations than do the Ganges and Meghna Rivers, which may be caused by the effects of local municipal discharge, industrial or urban wastes, and ferry crossing activities.


Assuntos
Metais Pesados/análise , Poluentes Químicos da Água/análise , Bangladesh , Monitoramento Ambiental , Sedimentos Geológicos , Rios
4.
BMC Plant Biol ; 19(1): 313, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31307374

RESUMO

BACKGROUND: Essential oils (EOs) of Lavandula angustifolia, mainly consist of monoterpenoids and sesquiterpenoids, are of great commercial value. The multi-flower spiciform thyrse of lavender not only determines the output of EOs but also reflects an environmental adaption strategy. With the flower development and blossom in turn, the fluctuation of the volatile terpenoids displayed a regular change at each axis. However, the molecular mechanism underlying the regulation of volatile terpenoids during the process of flowering is poorly understood in lavender. Here, we combine metabolite and RNA-Seq analyses of flowers of five developmental stages at first- and second-axis (FFDSFSA) and initial flower bud (FB0) to discover the active terpenoid biosynthesis as well as flowering-related genes. RESULTS: A total of 56 mono- and sesquiterpenoids were identified in the EOs of L. angustifolia 'JX-2'. FB0' EO consists of 55 compounds and the two highest compounds, ß-trans-ocimene (20.57%) and (+)-R-limonene (17.00%), can get rid of 74.71 and 78.41% aphids in Y-tube olfactometer experiments, respectively. With sequential and successive blossoms, temporally regulated volatiles were linked to pollinator attraction in field and olfaction bioassays. In three characteristic compounds of FFDSFSA' EOs, linalyl acetate (72.73%) and lavandulyl acetate (72.09%) attracted more bees than linalool (45.35%). Many transcripts related to flowering time and volatile terpenoid metabolism expressed differently during the flower development. Similar metabolic and transcriptomic profiles were observed when florets from the two axes were maintained at the same maturity grade. Besides both compounds and differentially expressed genes were rich in FB0, most volatile compounds were significantly correlated with FB0-specific gene module. Most key regulators related to flowering and terpenoid metabolism were interconnected in the subnetwork of FB0-specific module, suggesting the cross-talk between the two biological processes to some degree. CONCLUSIONS: Characteristic compounds and gene expression profile of FB0 exhibit ecological value in pest control. The precise control of each-axis flowering and regular emissions at transcriptional and metabolic level are important to pollinators attraction for lavender. Our study sheds new light on lavender maximizes its fitness from "gene-volatile terpenoid-insect" three layers.


Assuntos
Flores/genética , Redes Reguladoras de Genes , Lavandula/genética , Terpenos/metabolismo , Acetatos/metabolismo , Animais , Ecossistema , Flores/crescimento & desenvolvimento , Flores/metabolismo , Perfilação da Expressão Gênica , Insetos , Lavandula/crescimento & desenvolvimento , Lavandula/metabolismo , Monoterpenos/metabolismo , Odorantes , Óleos Voláteis/metabolismo , Óleos Vegetais/metabolismo , Polinização , RNA de Plantas , Análise de Sequência de RNA
5.
J Plant Physiol ; 236: 39-50, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30878012

RESUMO

Aerial bulbils, which resemble tiny bulbs, develop from axillary buds and facilitate rapid propagation of Lilium. In most species of lily, bulbils are perpetually dormant and little is known about induction of these vegetative structures. Herein, we proposed that strigolactones (SLs) may regulate the induction of bulbils in Lilium. We tested this hypothesis by isolating and investigating the expression patterns of 2 copies of the carotenoid cleavage dioxygenase8 (CCD8) gene in lily-LoCCD8a and LoCCD8b-with regard to biosynthesis of SLs. Expression analyses revealed that LoCCD8a principally is expressed during vegetative growth, whereas LoCCD8b mainly is expressed during reproductive growth. The maximum quantity of LoCCD8a transcripts was observed in the basal plate in most developmental stages, which suggests that SLs may originate from underground parts, especially the basal plate, and move upward. The effects of treatments with indole-3-acetic acid or SL analog (GR24) on outgrowth of bulbils and expression of LoCCD8 genes suggested that SLs function downstream of auxin to inhibit the outgrowth of bulbil. The expression patterns of LoCCD8a and LoCCD8b at sprouting and bulblet weighting stages also implied that SLs may function in nutrient redistribution. Our findings are expected to promote the utilization of bulbils as vegetative propagules for commercial practice.


Assuntos
Dioxigenases/metabolismo , Ácidos Indolacéticos/metabolismo , Lilium/metabolismo , Reguladores de Crescimento de Planta/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Clonagem Molecular , Dioxigenases/genética , Lilium/genética , Lilium/fisiologia , Proteínas de Plantas/genética , Raízes de Plantas/fisiologia , Reação em Cadeia da Polimerase em Tempo Real , Reprodução Assexuada , Transcriptoma
6.
J Cell Biochem ; 2019 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-30784118

RESUMO

Halophytes play a vital role in saline agriculture because these plants are necessary to increase the food supply to meet the demands of the growing world population. In addition, the transfer of salt-resistance genes from halophytes using genetic technologies has the potential to increase the salt tolerance of xerophytes. Characterization of some particularly promising halophyte model organisms has revealed the important new insights into the salt tolerance mechanisms used by plants. Numerous advances using these model systems have improved our understanding of salt tolerance regulation and salt tolerance-associated changes in gene expression, and these mechanisms have important implications for saline agriculture. Recent findings provide a basis for future studies of salt tolerance in plants, as well as the development of improved strategies for saline agriculture to increase yields of food, feed, and fuel crops.

7.
Front Plant Sci ; 10: 112, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30809236

RESUMO

Heading is a key agronomic trait of Chinese cabbage. A non-heading mutant with flat growth of heading leaves (fg-1) was isolated from an EMS-induced mutant population of the heading Chinese cabbage inbred line A03. In fg-1 mutant plants, the heading leaves are flat similar to rosette leaves. The epidermal cells on the adaxial surface of these leaves are significantly smaller, while those on the abaxial surface are much larger than in A03 plants. The segregation of the heading phenotype in the F2 and BC1 population suggests that the mutant trait is controlled by a pair of recessive alleles. Phytohormone analysis at the early heading stage showed significant decreases in IAA, ABA, JA and SA, with increases in methyl IAA and trans-Zeatin levels, suggesting they may coordinate leaf adaxial-abaxial polarity, development and morphology in fg-1. RNA-sequencing analysis at the early heading stage showed a decrease in expression levels of several auxin transport (BrAUX1, BrLAXs, and BrPINs) and responsive genes. Transcript levels of important ABA responsive genes, including BrABF3, were up-regulated in mid-leaf sections suggesting that both auxin and ABA signaling pathways play important roles in regulating leaf heading. In addition, a significant reduction in BrIAMT1 transcripts in fg-1 might contribute to leaf epinastic growth. The expression profiles of 19 genes with known roles in leaf polarity were significantly different in fg-1 leaves compared to wild type, suggesting that these genes might also regulate leaf heading in Chinese cabbage. In conclusion, leaf heading in Chinese cabbage is controlled through a complex network of hormone signaling and abaxial-adaxial patterning pathways. These findings increase our understanding of the molecular basis of head formation in Chinese cabbage.

8.
J Cell Physiol ; 234(6): 9723-9732, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30362575

RESUMO

Successful treatment of pancreatic cancer, which has the highest mortality rate among all types of malignancies, has challenged oncologists for decades, and early detection would undoubtedly increase favorable patient outcomes. The identification of proteins involved in pancreatic cancer progression could lead to biomarkers for early detection of this disease. This study identifies one potential candidate, cylindromatosis (CYLD), a deubiquitinase and microtubule-binding protein that plays a suppressive role in pancreatic cancer development. In pancreatic cancer samples, downregulation of CYLD expression resulted from a loss in the copy number of the CYLD gene; additionally, reduced expression of CYLD negatively correlated with the clinicopathological parameters. Further study demonstrated that CYLD deficiency promoted colony formation in vitro and pancreatic cancer growth in vivo. Mechanistic studies revealed that CYLD is essential for spindle orientation and properly oriented cell division; CYLD deficiency resulted in a substantial increase in chromosome missegregation. Taken together, these data indicate a critical role for CYLD in suppressing pancreatic tumorigenesis, implicating its potential as a biomarker for early detection of pancreatic cancer and a prognostic indicator of patient outcomes.


Assuntos
Carcinogênese/patologia , Enzima Desubiquitinante CYLD/deficiência , Mitose , Neoplasias Pancreáticas/enzimologia , Neoplasias Pancreáticas/patologia , Animais , Linhagem Celular Tumoral , Proliferação de Células , Segregação de Cromossomos , Enzima Desubiquitinante CYLD/metabolismo , Dosagem de Genes , Humanos , Camundongos , Neoplasias Pancreáticas/genética , Fuso Acromático/metabolismo , Ensaio Tumoral de Célula-Tronco
9.
Nat Commun ; 9(1): 5056, 2018 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-30498193

RESUMO

Long non-coding RNAs (lncRNAs) have emerged as important regulators of gene expression and plant development. Here, we identified 6,510 lncRNAs in Arabidopsis under normal or stress conditions. We found that the expression of natural antisense transcripts (NATs) that are transcribed in the opposite direction of protein-coding genes often positively correlates with and is required for the expression of their cognate sense genes. We further characterized MAS, a NAT-lncRNA produced from the MADS AFFECTING FLOWERING4 (MAF4) locus. MAS is induced by cold and indispensable for the activation of MAF4 transcription and suppression of precocious flowering. MAS activates MAF4 by interacting with WDR5a, one core component of the COMPASS-like complexes, and recruiting WDR5a to MAF4 to enhance histone 3 lysine 4 trimethylation (H3K4me3). Our study greatly extends the repertoire of lncRNAs in Arabidopsis and reveals a role for NAT-lncRNAs in regulating gene expression in vernalization response and likely in other biological processes.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas de Transporte/metabolismo , Proteínas de Domínio MADS/metabolismo , RNA Antissenso/metabolismo , RNA Longo não Codificante/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Transporte/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Domínio MADS/genética , Ligação Proteica , RNA Antissenso/genética , RNA Longo não Codificante/genética
10.
J Phys Chem Lett ; 9(24): 6999-7006, 2018 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-30499301

RESUMO

The instability issue of Pb-free Sn-based perovskite is one of the biggest challenges for its application in optoelectronic devices. Herein, a structural regulation strategy is demonstrated to regulate the geometric symmetry of formamidiniumtin iodide (FASnI3) perovskite. Experimental and theoretical works show that the introduction of cesium cation (Cs+) could improve the geometric symmetry, suppress the oxidation of Sn2+, and enhance the thermodynamical structural stability of FASnI3. As a result, the inverted planar Cs-doped FASnI3-based perovskite solar cell (PSC) is shown to maintain 90% of its initial power-conversion efficiency (PCE) after 2000 h stored in N2, which is the best durability to date for 3D Sn-based PSCs. Most importantly, the air, thermal, and illumination stabilities of the PSCs are all improved after Cs doping. The PCE of the Cs-doped PSC shows a 63% increase compared to that of the control device (from 3.74% to 6.08%) due to the improved quality of the Cs-doped FASnI3 film.

11.
J Phys Chem Lett ; 9(14): 3969-3977, 2018 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-29961330

RESUMO

The motion of CH3NH3+ cations in the low-temperature phase of the promising photovoltaic material methylammonium lead triiodide (CH3NH3PbI3) is investigated experimentally as well as theoretically, with a particular focus on the activation energy. Inelastic and quasi-elastic neutron scattering measurements reveal an activation energy of ∼48 meV. Through a combination of experiments and first-principles calculations, we attribute this activation energy to the relative rotation of CH3 against an NH3 group that stays bound to the inorganic cage. The inclusion of nuclear quantum effects through path integral molecular dynamics gives an activation energy of ∼42 meV, in good agreement with the neutron scattering experiments. For deuterated samples (CD3NH3PbI3), both theory and experiment observe a higher activation energy for the rotation of CD3 against NH3, which results from the smaller nuclear quantum effects in CD3. The rotation of the NH3 group, which is bound to the inorganic cage via strong hydrogen bonding, is unlikely to occur at low temperatures due to its high energy barrier of ∼120 meV.

12.
Plant J ; 93(5): 814-827, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29265542

RESUMO

Recently, long non-coding RNAs (lncRNAs) have been demonstrated to be involved in many biological processes of plants; however, a systematic study on transcriptional and, in particular, post-transcriptional regulation of stress-responsive lncRNAs in Oryza sativa (rice) is lacking. We sequenced three types of RNA libraries (poly(A)+, poly(A)- and nuclear RNAs) under four abiotic stresses (cold, heat, drought and salt). Based on an integrative bioinformatics approach and ~200 high-throughput data sets, ~170 of which have been published, we revealed over 7000 lncRNAs, nearly half of which were identified for the first time. Notably, we found that the majority of the ~500 poly(A) lncRNAs that were differentially expressed under stress were significantly downregulated, but approximately 25% were found to have upregulated non-poly(A) forms. Moreover, hundreds of lncRNAs with downregulated polyadenylation (DPA) tend to be highly conserved, show significant nuclear retention and are co-expressed with protein-coding genes that function under stress. Remarkably, these DPA lncRNAs are significantly enriched in quantitative trait loci (QTLs) for stress tolerance or development, suggesting their potential important roles in rice growth under various stresses. In particular, we observed substantially accumulated DPA lncRNAs in plants exposed to drought and salt, which is consistent with the severe reduction of RNA 3'-end processing factors under these conditions. Taken together, the results of this study reveal that polyadenylation and subcellular localization of many rice lncRNAs are likely to be regulated at the post-transcriptional level. Our findings strongly suggest that many upregulated/downregulated lncRNAs previously identified by traditional RNA-seq analyses need to be carefully reviewed to assess the influence of post-transcriptional modification.


Assuntos
Regulação da Expressão Gênica de Plantas , Oryza/genética , RNA Longo não Codificante/metabolismo , Estresse Fisiológico/genética , Sequência de Bases , Núcleo Celular/genética , Sequência Conservada , Regulação para Baixo , Secas , Oryza/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Poli A/genética , Poli A/metabolismo , Poliadenilação , Locos de Características Quantitativas , RNA Longo não Codificante/genética , RNA de Plantas/metabolismo
13.
Sci China Life Sci ; 61(2): 178-189, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29197026

RESUMO

MicroRNAs (miRNAs) are small non-coding RNAs that regulate a variety of biological processes. MiRNA expression often exhibits spatial and temporal specificity. However, genome-wide miRNA expression patterns in different organs during development of Arabidopsis thaliana have not yet been systemically investigated. In this study, we sequenced small RNA libraries generated from 27 different organ/tissue types, which cover the entire life cycle of Arabidopsis. Analysis of the sequencing data revealed that most miRNAs are ubiquitously expressed, whereas a small set of miRNAs display highly specific expression patterns. In addition, different miRNA members within the same family have distinct spatial and temporal expression patterns. Moreover, we found that some miRNAs are produced from different arms of their hairpin precursors at different developmental stages. This work provides new insights into the regulation of miRNA biogenesis and a rich resource for future investigation of miRNA functions in Arabidopsis.


Assuntos
Arabidopsis/genética , MicroRNAs/genética , RNA de Plantas/genética , Arabidopsis/crescimento & desenvolvimento , Biologia Computacional , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Biblioteca Gênica , Genoma de Planta/genética , Especificidade de Órgãos
14.
PLoS One ; 12(9): e0185302, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28945788

RESUMO

The determination of trace rare-earth elements (REEs) can be used for the assessment of environmental pollution, and is of great significance to the study of toxicity and toxicology in animals and plants. N, N, N', N'-tetraoctyl diglycolamide (TODGA) is an environmental friendly extractant that is highly selective to REEs. In this study, an analytical method was developed for the simultaneous determination of 16 trace REEs in simulated water samples by inductively coupled plasma optical emission spectroscopy (ICP-OES). With this method, TODGA was used as the extractant to perform the liquid-liquid extraction (LLE) sample pretreatment procedure. All 16 REEs were extracted from a 3 M nitric acid medium into an organic phase by a 0.025 M TODGA petroleum ether solution. A 0.03 M ethylenediaminetetraacetic acid disodium salt (EDTA) solution was used for back-extraction to strip the REEs from the organic phase into the aqueous phase. The aqueous phase was concentrated using a vacuum rotary evaporator and the concentration of the 16 REEs was detected by ICP-OES. Under the optimum experimental conditions, the limits of detection (3σ, n = 7) for the REEs ranged from 0.0405 ng mL-1 (Nd) to 0.5038 ng mL-1 (Ho). The relative standard deviations (c = 100 ng mL-1, n = 7) were from 0.5% (Eu) to 4.0% (Tm) with a linear range of 4-1000 ng mL-1 (R2 > 0.999). The recoveries of 16 REEs ranged from 95% to 106%. The LLE-ICP-OES method established in this study has the advantages of simple operation, low detection limits, fast analysis speed and the ability to simultaneously determine 16 REEs, thereby acting as a viable alternative for the simultaneous detection of trace amounts of REEs in water samples.


Assuntos
Metais Terras Raras/análise , Oligoelementos/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Glicolatos , Limite de Detecção , Extração Líquido-Líquido/métodos , Espectrofotometria/métodos
15.
Microbiologyopen ; 6(3)2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28105780

RESUMO

Pseudomonas aeruginosa is a good environmental microorganism capable of degrading decabromodiphenyl ether (BDE-209). This paper studied the effect of Cu2+ and humic acid (HA) extracted from e-waste contaminated soils on biodegradation of BDE-209 by P. aeruginosa. The adsorption isotherms of Cu2+ on HA, the crude enzyme activity, cell surface morphology, and biodegradation pathway were also investigated. The results showed that BDE-209 biodegradation by P. aeruginosa was inhibited at Cu2+ concentrations above 5 mg L-1 , but exhibited the best effect at the condition of 40 mg L-1 Cu2+  + 3 g L-1 HA. At the condition of 40 mg L-1 Cu2+  + 3 g L-1 HA, 97.35 ± 2.33% of the initial BDE-209 was degraded after 5 days, debromination efficiency was 72.14 ± 1.89%, crude enzyme activity reached the maximum of 0.519 ± 0.022U g-1 protein, cell surface of P. aeruginosa was smooth with normal short-rod shapes, and biodegradation pathway mainly include debromination, hydroxylation, and cleavage of the diphenyl ether bond. It was suggested that soil HA could eliminate the toxic effect of high Cu2+ concentrations and biodegradation of BDE-209 was improved by synergistic effect of HA and Cu2+ .


Assuntos
Antibacterianos/metabolismo , Cobre/metabolismo , Éteres Difenil Halogenados/metabolismo , Substâncias Húmicas , Pseudomonas aeruginosa/metabolismo , Microbiologia do Solo , Solo/química , Biotransformação , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/fisiologia , Poluentes do Solo/metabolismo , Oligoelementos/metabolismo
16.
Plant Cell Physiol ; 57(8): 1720-31, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27382127

RESUMO

Cadmium (Cd) is a transition metal that is highly toxic in biological systems. Anthropogenic emissions of Cd have increased biogeochemical cycling and the amount of Cd in the biosphere. Here we studied the utility of a bacterial Cd-binding protein, CadR, for the remediation of Cd contamination. CadR was successfully targeted to chloroplasts using a constitutive Cauliflower mosaic virus (CaMV) 35S promoter or a shoot-specific Chl a/b-binding protein 2 gene (CAB2) promoter and an RbcS (small subunit of the Rubisco complex) transit peptide. Under short-term (2 d) exposure to Cd, the cadR transgenic plants showed up to a 2.9-fold Cd accumulation in roots compared with untransformed plants. Under medium term (7 d) exposure to Cd, the concentrations of Cd in leaves began to increase but there were no differences between the wild type and the cadR transgenic plants. Under long-term (16 d) exposure to Cd, the cadR transgenic plants accumulated greater amounts of Cd in leaves than the untransformed plants. Total Cd accumulation (µg per plant) in shoots and roots of the plants expressing cadR were significantly higher (up to 3.5-fold in shoots and 5.2-fold in roots) than those of the untransformed plants. We also found that targeting CadR to chloroplasts facilitated chloroplastic metal homeostasis and Chl b accumulation. Our results demonstrate that manipulating chelating capacity in chloroplasts or in the cytoplasm may be effective in modifying both the accumulation of and resistance to Cd.


Assuntos
Arabidopsis/fisiologia , Cádmio/metabolismo , Metalotioneína/metabolismo , Arabidopsis/citologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biodegradação Ambiental , Cádmio/toxicidade , Caulimovirus/genética , Clorofila/metabolismo , Cloroplastos/metabolismo , Expressão Gênica , Genes Reporter , Homeostase , Inativação Metabólica , Metalotioneína/genética , Minerais/metabolismo , Raízes de Plantas/citologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/fisiologia , Brotos de Planta/citologia , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/genética , Brotos de Planta/fisiologia , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas/genética , Plântula/citologia , Plântula/efeitos dos fármacos , Plântula/genética , Plântula/fisiologia , Transgenes
17.
Biochim Biophys Acta ; 1859(1): 155-62, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26112461

RESUMO

Long non-coding RNAs (lncRNAs) have been emerged as important players for various biological pathways, including dosage compensation, genomic imprinting, chromatin regulation, alternative splicing and nuclear organization. A large number of lncRNAs had already been identified by different approaches in plants, while the functions of only a few of them have been investigated. This review will summarize our current understanding of a wide range of plant lncRNAs functions, and highlight their roles in the regulation of diverse pathways in plants. This article is part of a Special Issue entitled: Clues to long noncoding RNA taxonomy1, edited by Dr. Tetsuro Hirose and Dr. Shinichi Nakagawa.


Assuntos
Processamento Alternativo/genética , Cromatina/genética , Impressão Genômica , RNA Longo não Codificante/genética , Núcleo Celular , Plantas/genética
18.
J Nanosci Nanotechnol ; 15(12): 9874-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26682427

RESUMO

Dispersions of multi-walled carbon nanotubes (MW-CNTs) assisted by non-covalent surface modification and covalent surface modification were prepared using different concentration of gallic acid aqueous solution. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to investigate the dispersion states and effect of MWNTs. FTIR results demonstrate that concentration of gallic acid has great effect on the surface modification of multi-walled carbon nanotubes. With the content of gallic acid increasing, modification effect were firstly increased and then decreased in that the optimal concentration is about 10 µg/ml as it is its solubility in water. SEM and TEM results also show that gallic acid not only can ensure the integrity of the MW-CNTs, but also can purify it. These results confirmed achievement of a good dispersion state and effect of MW-CNTs with gallic acid. The dispersion mechanism of non-covalent surface modification and covalent surface modification was analyzed.

19.
Int J Environ Res Public Health ; 12(9): 11829-47, 2015 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-26393637

RESUMO

The biodegradation effect and mechanism of decabromodiphenyl ether (BDE-209) by crude enzyme extract from Pseudomonas aeruginosa were investigated. The results demonstrated that crude enzyme extract exhibited obviously higher degradation efficiency and shorter biodegradation time than Pseudomonas aeruginosa itself. Under the optimum conditions of pH 9.0, 35 °C and protein content of 2000 mg/L, 92.77% of the initial BDE-209 (20 mg/L) was degraded after 5 h. A BDE-209 biodegradation pathway was proposed on the basis of the biodegradation products identified by GC-MS analysis. The biodegradation mechanism showed that crude enzyme extract degraded BDE-209 into lower brominated PBDEs and OH-PBDEs through debromination and hydroxylation of the aromatic rings.


Assuntos
Poluentes Ambientais/metabolismo , Recuperação e Remediação Ambiental/métodos , Éteres Difenil Halogenados/metabolismo , Pseudomonas aeruginosa/enzimologia , Biodegradação Ambiental , Retardadores de Chama/metabolismo
20.
Phytochemistry ; 116: 28-37, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25840728

RESUMO

Hypoxia is one of the main environmental stresses that accounts for decreasing crop yield. To further investigate the mechanisms whereby exogenous GABA alleviates hypoxia injury to melon seedlings, a comparative proteomic analysis was performed using roots subjected to normal aeration and hypoxia conditions with or without GABA (5mM). The results indicated that protein spots on gels after hypoxia and hypoxia+GABA treatment were significantly changed. Three "matched sets" were analyzed from four treatments, and 13 protein spots with large significant differences in expression were identified by MALDI-TOF/TOF mass spectrometry. Exogenous GABA treatment enhanced the expression of protein in cytosolic phosphoglycerate kinase 1, exaA2 gene product, dnaJ and myb-like DNA-binding domain-containing proteins, as well as elongation factor-1 alpha and hypothetical proteins in hypoxia-induced roots. However, the hypoxia+GABA treated roots had a significantly lower expression of proteins including malate dehydrogenase, nucleoside diphosphate kinase, disease resistance-like protein, disulfide isomerase, actin, ferrodoxin NADP oxidoreductase, glutathione transferase, netting associated peroxidase. This paper describes the effect of GABA on melon plants under hypoxia-induced stress using proteomics, and supports the alleviating function of GABA in melon plants grown under hypoxic conditions.


Assuntos
Cucurbitaceae/química , Hipóxia , Proteômica , Ácido gama-Aminobutírico/farmacologia , Proteínas de Ligação a DNA/metabolismo , Peroxidases/metabolismo , Raízes de Plantas/química , Raízes de Plantas/efeitos dos fármacos , Plântula/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Estresse Fisiológico/efeitos dos fármacos , Ácido gama-Aminobutírico/análise
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