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1.
Rev Sci Instrum ; 95(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38341725

RESUMO

A nitrogen-vacancy center based scanning magnetic microscope can be used to characterize magnetics at the nanoscale with high sensitivity. This paper reports a field-programmable-gate-array based hardware system that is designed to realize control and signal readout for fast scanning magnetic imaging with a nitrogen-vacancy center. A 10-channel 1 Msps @ 20 bit analog signal generator, a 12-channel 50 ps resolution pulse generator, a 300 Msps @ 16 bit lock-in amplifier with proportional integral derivative control function, and a 4-channel 200 Msps counter are integrated on the platform. A customized acceleration algorithm is realized with the re-configurable field-programmable-gate-array chip to accelerate the imaging speed of the nitrogen-vacancy system, and the experimental results prove that the imaging efficiency can be accelerated by five times compared to the system without the acceleration algorithm. The platform has considerable potential for future applications of fast scanning magnetic imaging.

2.
Bioresour Technol ; 395: 130337, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38244937

RESUMO

Addressing the environmental contamination from heavy metals and organic pollutants remains a critical challenge. This study explored the resilience and removal potential of Pleurotus ostreatus GEMB-PO1 for copper. P. ostreatus GEMB-PO1 showed significant tolerance, withstanding copper concentrations up to 2 mM. Its copper removal efficiency ranged from 64.56 % at 0.5 mM to 22.90 % at 8 mM. Transcriptomic insights into its response to copper revealed a marked upregulation in xenobiotic degradation-related enzymes, such as laccase and type II peroxidases. Building on these findings, a co-remediation system using P. ostreatus GEMB-PO1 was developed to remove both copper and organic pollutants. While this approach significantly enhanced the degradation efficiency of organic contaminants, it concurrently exhibited a diminished efficacy in copper removal within the composite system. This study underscores the potential of P. ostreatus GEMB-PO1 in environmental remediation. Nevertheless, further investigation is required to optimize the simultaneous removal of organic pollutants and copper.


Assuntos
Poluentes Ambientais , Metais Pesados , Pleurotus , Cobre/metabolismo , Pleurotus/metabolismo , Poluentes Ambientais/metabolismo , Metais Pesados/metabolismo , Peroxidases/metabolismo , Lacase/metabolismo , Biodegradação Ambiental
3.
Plants (Basel) ; 12(23)2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38068705

RESUMO

High temperatures accelerate the accumulation of storage material in seeds, often leading to defects in grain filling. However, the mechanisms regulating grain filling at high temperatures remain unknown. Here, we want to explore the quality factors influenced by the environment and have identified a LATE EMBROYGENESIS ABUNDANT gene, OsLEA1b, a heat-stress-responsive gene in rice grain filling. OsLEA1b is highly expressed in the endosperm, and its coding protein localizes to the nucleus and cytoplasm. Knock-out mutants of OsLEA1b had abnormal compound starch granules in endosperm cells and chalky endosperm with significantly decreased grain weight and grain number per panicle. The oslea1b mutants exhibited a lower proportion of short starch chains with degrees of polymerization values from 6 to 13 and a higher proportion of chains with degrees from 14 to 48, as well as significantly lower contents of starch, protein, and lipid compared to the wild type. The difference was exacerbated under high temperature conditions. Moreover, OsLEA1b was induced by drought stress. The survival rate of oslea1b mutants decreased significantly under drought stress treatment, with significant increase in ROS levels. These results indicate that OsLEA1b regulates starch biosynthesis and influences rice grain quality, especially under high temperatures. This provides a valuable resource for genetic improvement in rice grain quality.

4.
Materials (Basel) ; 16(18)2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37763454

RESUMO

TiAl alloys are high-temperature structural materials with excellent comprehensive properties, and their ideal service temperature range is about 700-950 °C. High-Nb containing the Ti-46Al-8Nb-2.5V alloy was subjected to hot compression and subsequent annealing at 900 °C. During hot compression, work-hardening and strain-softening occurred. The peak stresses during compression are positively correlated with the compressive strain rates and negatively correlated with the compression temperatures. The α2 phase exhibited a typical (0001)α2 basal plane texture after hot compression, while the ß0 and γ phases did not show a typical strong texture. Subsequent annealing at 900 °C of the hot-compressed samples resulted in significant phase transformations, specifically the α2 → γ and ß0 → γ phase transformations. After 30 min of annealing, the volume fraction of the α2 phase decreased from 39.0% to 4.6%. The microstructure characteristics and phase fraction after 60 min of annealing were similar to those after 30 min. According to the calculation of Miller indexes and texture evolution during annealing, the α2 → γ phase transformation did not follow the Blackburn orientation relationship. Multiple crystal-oriented α2 phases with nanoscale widths (20~100 nm) precipitate within the γ phase during the annealing process, which means the occurrence of γ → α2 phase transformation. Still, the γ → α2 phase transformation follows the Blackburn orientation relationship.

5.
Small Methods ; 7(7): e2300168, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37148175

RESUMO

Lithium metal anode attracts great attention because of its high specific capacity and low redox potential. However, the uncontrolled dendrite growth and its infinite volume expansion during cycling are extremely detrimental to the practical application. The formation of a solid electrolyte interphase (SEI) plays a decisive role in the behavior of lithium deposition/dissolution during electrochemical processing. Clarifying the essential relationship between SEI and battery performance is a priority. Research in SEI is accelerated in recent years by the use of advanced simulation tools and characterization techniques. The chemical composition and micromorphology of SEIs with various electrolytes are analyzed to clarify the effects of SEI on the Coulombic efficiency and cycle life. In this review, the recent research progress focused on the composition and structure of SEI is summarized, and various advanced characterization techniques applied to the investigation of SEI are discussed. The comparisons of the representative experimental results and theoretical models of SEI in lithium metal batteries (LMBs) are exhibited, and the underneath mechanisms of interaction between SEI and the electrochemical properties of the cell are highlighted. This work offers new insights into the development of safe LMBs with higher energy density.

6.
Ecotoxicol Environ Saf ; 254: 114697, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36889210

RESUMO

Advanced oxidation processes (AOPs) are a class of highly efficient pollution remediation technologies that produce oxidising radicals under specific conditions to degrade organic pollutants. The Fenton reaction is a commonly applied AOP. To combine the advantages of AOPs and biodegradation in the remediation of organic pollutants, some studies have developed coupled systems between Fenton AOPs and white rot fungi (WRF) for environmental organic pollutant remediation and have achieved some success. Moreover, a promising system, termed as advanced bio-oxidation processes (ABOPs), mediated by the quinone redox cycling of WRF, has attracted increasing attention in the field. In this ABOP system, the radicals and H2O2 produced through the quinone redox cycling of WRF can strengthen Fenton reaction. Meanwhile, in this process, the reduction of Fe3+ to Fe2+ ensures the maintenance of Fenton reaction, leading to a promising application potential for the remediation of environmental organic pollutants. ABOPs combine the advantages of bioremediation and advanced oxidation remediation. Further understanding the coupling of Fenton reaction and WRF in the degradation of organic pollutants will be of great significance for the remediation of organic pollutants. Therefore, in this study, we reviewed recent remediation techniques for organic pollutants involving the coupled application of WRF and the Fenton reaction, focusing on the application of new ABOPs mediated by WRF, and discussed the reaction mechanism and conditions of ABOPs. Finally, we discussed the application prospects and future research directions of the joint application of WRF and advanced oxidation technologies for the remediation of environmental organic pollutants.


Assuntos
Poluentes Ambientais , Recuperação e Remediação Ambiental , Poluentes Químicos da Água , Peróxido de Hidrogênio , Oxirredução , Fungos/metabolismo , Poluentes Químicos da Água/metabolismo
7.
Plant Commun ; 3(6): 100463, 2022 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-36258666

RESUMO

Starch and storage proteins are the main components of rice (Oryza sativa L.) grains. Despite their importance, the molecular regulatory mechanisms of storage protein and starch biosynthesis remain largely elusive. Here, we identified a rice opaque endosperm mutant, opaque3 (o3), that overaccumulates 57-kDa proglutelins and has significantly lower protein and starch contents than the wild type. The o3 mutant also has abnormal protein body structures and compound starch grains in its endosperm cells. OPAQUE3 (O3) encodes a transmembrane basic leucine zipper (bZIP) transcription factor (OsbZIP60) and is localized in the endoplasmic reticulum (ER) and the nucleus, but it is localized mostly in the nucleus under ER stress. We demonstrated that O3 could activate the expression of several starch synthesis-related genes (GBSSI, AGPL2, SBEI, and ISA2) and storage protein synthesis-related genes (OsGluA2, Prol14, and Glb1). O3 also plays an important role in protein processing and export in the ER by directly binding to the promoters and activating the expression of OsBIP1 and PDIL1-1, two major chaperones that assist with folding of immature secretory proteins in the ER of rice endosperm cells. High-temperature conditions aggravate ER stress and result in more abnormal grain development in o3 mutants. We also revealed that OsbZIP50 can assist O3 in response to ER stress, especially under high-temperature conditions. We thus demonstrate that O3 plays a central role in rice grain development by participating simultaneously in the regulation of storage protein and starch biosynthesis and the maintenance of ER homeostasis in endosperm cells.


Assuntos
Endosperma , Oryza , Endosperma/genética , Endosperma/metabolismo , Oryza/genética , Oryza/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Amido/metabolismo , Grão Comestível/metabolismo
8.
PLoS One ; 17(1): e0261822, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35030196

RESUMO

Rice (Oryza sativa L.) is one of the most important species for food production worldwide. Low temperature is a major abiotic factor that affects rice germination and reproduction. Here, the underlying regulatory mechanism in seedlings of a TGMS variety (33S) and a cold-sensitive variety (Nipponbare) was investigated by comparative transcriptome. There were 795 differentially expressed genes (DEGs) identified only in cold-treated 33S, suggesting that 33S had a unique cold-resistance system. Functional and enrichment analysis of these DEGs revealed that, in 33S, several metabolic pathways, such as photosynthesis, amino acid metabolism, secondary metabolite biosynthesis, were significantly repressed. Moreover, pathways related to growth and development, including starch and sucrose metabolism, and DNA biosynthesis and damage response/repair, were significantly enhanced. The expression of genes related to nutrient reserve activity were significantly up-regulated in 33S. Finally, three NAC and several ERF transcription factors were predicted to be important in this transcriptional reprogramming. This present work provides valuable information for future investigations of low-temperature response mechanisms and genetic improvement of cold-tolerant rice seedlings.


Assuntos
Aclimatação , Regulação da Expressão Gênica de Plantas , Oryza , Proteínas de Plantas , Plântula , Transcriptoma , Temperatura Baixa , Perfilação da Expressão Gênica , Oryza/genética , Oryza/crescimento & desenvolvimento , Fotossíntese , Proteínas de Plantas/biossíntese , Proteínas de Plantas/genética , Plântula/genética , Plântula/crescimento & desenvolvimento , Amido/biossíntese , Amido/genética
9.
Phys Rev Lett ; 129(25): 250501, 2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36608231

RESUMO

Triply degenerate points (TDPs), which correspond to new types of topological semimetals, can support novel quasiparticles possessing effective integer spins while preserving Fermi statistics. Here by mapping the momentum space to the parameter space of a three-level system in a trapped ion, we experimentally explore the transitions between different types of TDPs driven by spin-tensor-momentum couplings. We observe the phase transitions between TDPs with different topological charges by measuring the Berry flux on a loop surrounding the gap-closing lines, and the jump of the Berry flux gives the jump of the topological charge (up to a 2π factor) across the transitions. For the Berry flux measurement, we employ a new method by examining the geometric rotations of both spin vectors and tensors, which lead to a generalized solid angle equal to the Berry flux. The controllability of a multilevel ion offers a versatile platform to study high-spin physics, and our Letter paves the way to explore novel topological phenomena therein.

10.
Plant Biotechnol J ; 20(2): 350-359, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34582079

RESUMO

Two type II-C Cas9 orthologs (Nm1Cas9 and Nm2Cas9) were recently identified from Neisseria meningitidis and have been extensively used in mammalian cells, but whether these NmCas9 orthologs or other type II-C Cas9 proteins can mediate genome editing in plants remains unclear. In this study, we developed and optimized targeted mutagenesis systems from NmCas9s for plants. Efficient genome editing at the target with N4 GATT and N4 CC protospacer adjacent motifs (PAMs) was achieved with Nm1Cas9 and Nm2Cas9 respectively. These results indicated that a highly active editing system could be developed from type II-C Cas9s with distinct PAM preferences, thus providing a reliable strategy to extend the scope of genome editing in plants. Base editors (BEs) were further developed from the NmCas9s. The editing efficiency of adenine BEs (ABEs) of TadA*-7.10 and cytosine BEs (CBEs) of rat APOBEC1 (rAPO1) or human APOBEC3a (hA3A) were extremely limited, whereas ABEs of TadA-8e and CBEs of Petromyzon marinus cytidine deaminase 1 (PmCDA1) exhibited markedly improved performance on the same targets. In addition, we found that fusion of a single-stranded DNA-binding domain from the human Rad51 protein enhanced the base editing capability of rAPO1-CBEs of NmCas9s. Together, our results suggest that the engineering of NmCas9s or other type II-C Cas9s can provide useful alternatives for crop genome editing.


Assuntos
Neisseria meningitidis , Oryza , Desaminase APOBEC-1/genética , Adenina , Animais , Sistemas CRISPR-Cas/genética , Citidina Desaminase , Edição de Genes/métodos , Mamíferos/genética , Neisseria meningitidis/genética , Oryza/genética , Proteínas , Ratos
11.
Acta Orthop Traumatol Turc ; 55(5): 377-384, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34730521

RESUMO

OBJECTIVE: The aim of this study was to compare the histological results of Accordion Maneuver (AM) with Compression Technique Alone (CA) in the treatment of atrophic fracture nonunion in a rabbit model. METHODS: The study was performed on 91 male New Zealand rabbits aged six months, weighing 3.1 to 3.6 kg. The standardized models of atrophic nonunion with a 3-mm fracture were created in the tibias of rats. For the histomorphological study, 22 rabbits were randomly selected and sacrificed. The remaining 69 rabbits were divided into two groups based on the treatment technique: Group AM (n = 36) and Group CA (n = 33). The group AM was further randomly divided into four subgroups based on the amplitude and interval parameters: subgroup A1B1 (0 day, 4 mm; n = 9), subgroup A1B2 (0 day, 8 mm; n = 7), subgroup A2B1 (6 days, 4 mm; n = 10), and subgroup A2B2 (6 days, 8 mm; n = 10). A monolateral external fixator was employed in each group. Animals were sacrificed 6 weeks after the treatment, and bony healing was assessed both radiologically and histologically. The efficiency of bony healing was assessed using the bone content index, bone mineral density, and bone volume fraction indexes. RESULTS: In X-ray and micro-computed tomography assessments, periosteal reaction was detected at the fracture site in all specimens. In group CA, sclerosis was observed at the ends of the fragments. Bony absorption, nonunion, and a little amount of island-like high density were also observed at the nonunion site. Among AM subgroups, sparse callus-like bone formation in A1B1 subgroup and a high density of callus connecting most parts of the gap and large amount of periosteal callus formation in A1B1 subgroup were observed. In A2B2 subgroup, the cortex was initially connected. No gap was observed, and the medullary cavity was recanalized. In histological analyses, the intermission of 0 day at rate of 8 mm was of the highest level of bony regeneration, and the intermission of 6 days at the rate of 4 mm was of the lowest level of bony regeneration (P < 0.05). CONCLUSION: Based on the radiological and histological results obtained from the present study, AM seems to be more effective than CA in treating atrophic nonunion. AM can shorten the period of treatment. The interval of 0 day and an amplitude of 8 mm may be more proper for AM.


Assuntos
Fraturas Ósseas , Fraturas não Consolidadas , Animais , Regeneração Óssea , Calo Ósseo/diagnóstico por imagem , Consolidação da Fratura , Masculino , Coelhos , Ratos , Microtomografia por Raio-X
12.
Mol Breed ; 41(10): 65, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34642568

RESUMO

Yanfeng 47 (YF47) is an elite japonica rice variety cultivated in China on nearly 2 million hectares over the past 20 years. However, YF47 is highly susceptible to rice blast (Magnaporthe oryzae), one of the most destructive rice diseases. In this study, we developed novel TPAP (tetra-primer ARMS-PCR) functional markers for the genes Pita, Pib, and Pid2, all of which afford broad-spectrum resistance to blast. A collection of 91 japonica rice germplasms with similar ecological characteristics to YF47 were screened, and Wuyunjing 27 (WYJ27) with Pita and Pib alleles and P135 with the Pid2 allele were identified. Furthermore, the corresponding positive Pita, Pib, and Pid2 alleles were transferred into YF47 using single, mutual, and backcrosses, together with molecular marker-assisted selection (MAS) and anther culture technology. These genetic materials, carrying one, two, or three functional alleles, were generated within 3 years, and compared to YF47, they all showed improved resistance to naturally inoculated rice blast. Further improved lines (IL) 1 to 5 (all containing Pita, Pib, and Pid2 alleles) were evaluated for yield performance, and when no fungicide was applied, all lines except IL-4 showed increased traits compared with those of YF47. IL-5, renamed Yanjing 144 (YJ144), showed yield increases in the Liaoning province regional variety comparison test and superior appearance quality compared to YF47. Our work provides a molecular design strategy for pyramiding multiple beneficial genes to rapidly improve rice blast resistance, yield, and quality using multiple breeding strategies. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s11032-021-01259-4.

13.
Rice (N Y) ; 14(1): 74, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34374880

RESUMO

Long grain geng/japonica rice has a higher market preference due its excellent appearance quality. The dense and erect-panicle 1 (dep1) gene has been widely used in the breeding of high-yielding geng/japonica rice cultivars in China. However, this gene causes short and round grain shape thus making it less attractive in global rice markets. Therefore, breeding of high-yielding long-grain geng/japonica rice cultivars by incorporating dep1 with major-effect grain shape gene is of high priority in rice industry. Up to now, multiple grain shape genes' effect mechanism has been clearly elaborated, however, under the background of erect-panicle geng/japonica rice, the effect of major grain shape genes on the appearance quality need to be further clarified, as detailed reports are limited. Utilizing CRISPR/Cas9 technology, a series of near-isogenic lines (NILs) (YF47dep1-gw8, YF47dep1-gs3, YF47dep1-gl7, YF47dep1-qgl3 and YF47dep1-tgw6) in Yanfeng 47(YF47dep1) background were created. Grain appearance and yield components analysis showed that: (1) All NILs' grain length to width ratio was significantly increased compared to that of YF47dep1, excepted YF47dep1-gs3, (2) The chalkiness degree was significantly reduced in all of the NILs, (3) In all of the NILs, YF47dep1-gw8 grains exhibited the greatest length to width ratio and the lowest chalkiness degree, (4) The composition of glume cells and filling characteristics of the endosperm were two key factors contributing grain shape and grain chalk variations, respectively, and v) Owning to a substantial increase in the thousand grain weight, the yields of YF47dep1-gs3 and YF47dep1-tgw6 were significantly higher than that of YF47dep1, whereas YF47dep1-qgl3 exhibited the lowest yield because of a dramatic decrease in the effective panicle number and thousand grain weight. All the results revealed that pyramiding dep1 with major-effect grain shape alleles was an effective approach to improving the appearance quality of erect-panicle geng/japonica rice, owning to both of the appearance quality and yield improvement, GS3 and TGW6 alleles can be applied directly for breeding long-grain shape geng/japonica rice, and editing GW8 resulted in excellent appearance quality but low yield, therefore, this gene would be difficult to use directly but can be considered as the core germplasm resource.

14.
Interdiscip Sci ; 13(4): 703-716, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34236625

RESUMO

BACKGROUND: Prediction of protein solubility is an indispensable prerequisite for pharmaceutical research and production. The general and specific objective of this work is to design a new model for predicting protein solubility by using protein sequence feature fusion and deep dual-channel convolutional neural networks (DDcCNN) to improve the performance of existing prediction models. METHODS: The redundancy of raw protein is reduced by CD-HIT. The four subsequences are built from protein sequence: one global and three locals. The global subsequence is the entire protein sequence, and these local subsequences are obtained by moving a sliding window with some rules. Using G-gap to extract the features of the above four subsequences, a mixed matrix is constructed as the input of one channel which is composed of three-layer convolutional operating. Additional features are extracted by SCRATCH tool as input of another channel, which is consist of a single convolution in order to find hidden relationships and improve the accuracy of predictor. The outputs of two parallel channels are concatenated as the input of the hidden layer. And the prediction of protein solubility is obtained in the output layer. The best protein solubility prediction model is obtained by doing some comparative experiments of different frameworks. RESULTS: The performance indicators of DDcCNN model (our designed) are as follows: accuracy of 77.82%, Matthew's correlation coefficient of 0.57, sensitivity of 76.13% and specificity of 79.32%. The results of some comparative experiments show that the overall performance of DDcCNN model is better than existing models (GCNN, LCNN and PCNN). The related models and data are publicly deposited at http://www.ddccnn.wang . CONCLUSION: The satisfactory performance of DDcCNN model reveals that these features and flexible computational methodologies can reinforce the existing prediction models for better prediction of protein solubility could be applied in several applications, such as to preselect initial targets that are soluble or to alter solubility of target proteins, thus can help to reduce the production cost.


Assuntos
Redes Neurais de Computação , Proteínas , Sequência de Aminoácidos , Domínios Proteicos , Solubilidade
15.
Rev Sci Instrum ; 91(2): 024708, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32113441

RESUMO

A field-programmable-gate-array (FPGA) based time-to-digital-converter (TDC), which combines different types of delay chains in a single time measurement channel, is reported in this paper. A new TDC architecture is developed, and both a carry-chain and the DSP48E1 adders, which are integrated inside the FPGA chip, are employed to achieve high resolution time tagging. A single channel TDC has a 3.3 ps averaged bin size, a 5.4 ps single-shot precision, and a maximum sampling rate of 250 MSa/s. The differential-non-linearity of the single TDC channel is -3.3 ps/+24.1 ps, and the integral-non-linearity is within -10.4 ps/+68.6 ps. The TDC performance can be improved by using four TDC channels to measure one input signal, and a 3.4 ps single-shot precision can be obtained. Due to the implementation of the delicated TDC structure, only a small amount of digital resources is required to achieve the picosecond time measurement resolution. Therefore, the reported TDC architecture is suitable for multi-channel applications that require high time resolution measurements of multiple input signals.

16.
Int J Mol Sci ; 21(5)2020 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-32182761

RESUMO

Drought is a serious problem, which causes heavy yield losses for rice. Heat-shock factors (HSFs) had been implicated in tolerance to drought and high temperature. However, there has not been much functional characterization and mechanism clarification in rice. Previously, we found an HSF gene, OsHSFA3, was highly related with drought tolerance after screening from 10,000 different samples. Herein, we cloned the OsHSFA3 from rice and overexpressed it in Arabidopsis thaliana to study its regulatory mechanism of drought tolerance. Phenotypic and physiological assays of the transgenic Arabidopsis lines showed that overexpression of OsHSFA3 confers drought tolerance by reducing water loss and reactive oxygen species (ROS) levels, whereas it increases abscisic acid (ABA) levels. However, enzymatic antioxidants such as activity levels of superoxide dismutase, peroxidase and catalase were not significantly different between wild type and transgenic lines. Instead, we observed a significant increase in polyamine content, which was correlated with increased AtADC1, AtADC2, SPDS1 and SPMS expression levels. In silico and in vivo analyses confirmed that OsHSFA3 is a nuclear-localized gene. In addition, OsHSFA3 can bind to the promoter of AtADC1 and OsADC via a yeast one-hybrid assay. Overall, this study reveals that OsHSFA3 improves drought tolerance in Arabidopsis not only by increasing ABA levels, but also by modulating polyamine levels to maintain ROS homeostasis, therefore it could be a strong candidate to develop drought-tolerant rice cultivars.


Assuntos
Oryza/genética , Oryza/fisiologia , Proteínas de Plantas/genética , Poliaminas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico/genética , Ácido Abscísico/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/fisiologia , Secas , Regulação da Expressão Gênica de Plantas/genética , Oryza/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Plantas Geneticamente Modificadas/fisiologia
17.
Genes (Basel) ; 10(9)2019 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-31533315

RESUMO

Rice, being a major staple food crop and sensitive to salinity conditions, bears heavy yield losses due to saline soil. Although some salt responsive genes have been identified in rice, their applications in developing salt tolerant cultivars have resulted in limited achievements. Herein, we used bioinformatic approaches to perform a meta-analysis of three transcriptome datasets from salinity and control conditions in order to reveal novel genes and the molecular pathways underlying rice response to salt. From a total of 28,432 expressed genes, we identify 457 core differentially expressed genes (DEGs) constitutively responding to salt, regardless of the stress duration, genotype, or the tissue. Gene co-expression analysis divided the core DEGs into three different modules, each of them contributing to salt response in a unique metabolic pathway. Gene ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses highlighted key biological processes and metabolic pathways involved in the salt response. We identified important novel hub genes encoding proteins of different families including CAM, DUF630/632, DUF581, CHL27, PP2-13, LEA4-5, and transcription factors, which could be functionally characterized using reverse genetic experiments. This novel repertoire of candidate genes related to salt response in rice will be useful for engineering salt tolerant varieties.


Assuntos
Regulação da Expressão Gênica de Plantas , Oryza/genética , Tolerância ao Sal , Transcriptoma , Redes Reguladoras de Genes , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
18.
Bioinformation ; 15(7): 480-489, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31485134

RESUMO

Drought is one of the major abiotic stresses causing yield losses and restricted growing area for several major crops. Rice being a major staple food crop and sensitive to water-deficit conditions bears heavy yield losses due to drought stress. To breed drought tolerant rice cultivars, it is of interest to understand the mechanisms of drought tolerance. In this regard, large amount of publicly available transcriptome datasets could be utilized. In this study, we used different transcriptome datasets obtained under drought stress in comparison to normal conditions (control) to identify novel drought responsive genes and their underlying molecular mechanisms. We found 517 core drought responsive differentially expressed genes (DEGs) and different modules using gene co-expression analysis to specifically predict their biological roles in drought tolerance. Gene ontology and KEGG analyses showed key biological processes and metabolic pathways involved in drought tolerance. Further, network analysis pinpointed important hub DEGs and major transcription factors regulating the expression of drought responsive genes in each module. These identified novel DEGs and transcription factors could be functionally characterized using systems biology approaches, which can significantly enhance our knowledge about the molecular mechanisms of drought tolerance in rice.

19.
Rev Sci Instrum ; 89(10): 104706, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30399906

RESUMO

A pulse forming module (PFM) with a multifunction of energy storage and a quasi-squared pulse output is developed to meet the challenge of a compact design and square output waveform in a high-power Marx generator. A simplified pulse forming circuit comprising only 2 parallel connected LC sections, in which every section contains an inductor and a capacitor in series, has been proposed and investigated carefully to obtain a quasi-squared waveform. Influences of inductance values in the circuit on its output waveform to a resistive load are investigated. PFMs are designed and fabricated based on the 2 LC section circuit, in which series folded film capacitors are employed to achieve a high energy density of 0.04 J/cm3 at a charging voltage of 120 kV. The as-designed module can output a quasi-squared waveform with FWHM of about 180 ns and the flattop duration greater than 90 ns. It can work at a repetition rate as high as 50 Hz, while the output waveforms show small differences. This research has developed a PFM with a quasi-squared output waveform based on a simplified 2 LC section circuit, which shows potential to reduce the size of the high power generator system that is based on it.

20.
Appl Plant Sci ; 6(5): e01153, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-30131895

RESUMO

PREMISE OF THE STUDY: Polymorphic microsatellite primers were developed for greater duckweed, Spirodela polyrhiza (Lemnaceae), to investigate genetic diversity and structure for application in a bioremediation program. METHODS AND RESULTS: A total of 401 publicly available S. polyrhiza whole-genome shotgun sequences were searched for simple sequence repeat loci of two or more nucleotides. Of these, 60 primer pairs were selected to analyze 68 individuals of S. polyrhiza from three populations. Nineteen polymorphic microsatellite loci were developed. A total of 108 alleles were detected with an average of 5.7 alleles per locus. The levels of expected and observed heterozygosity were 0.0511-0.8669 and 0-0.8750, respectively. Ten loci also successfully amplified in 16 individuals of Lemna perpusilla. CONCLUSIONS: The results demonstrate the broad utility of these microsatellite loci for studying population genetics in S. polyrhiza.

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