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1.
RSC Adv ; 14(3): 2088-2101, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38196908

RESUMEN

Novel 2D material-based supercapacitors are promising candidates for energy applications due to their distinctive physical, chemical, and electrochemical properties. In this study, a dandelion-like structure material comprised of Sm2O3, Co3O4, and 2D reduced graphene oxide (rGO) on nickel foam (NF) was synthesised using a hydrothermal method followed by subsequent annealing treatment. This dandelion composite grows further through the tremella-like structure of Sm2O3 and Co3O4, which facilitates the diffusion of ions and prevents structural collapse during charging and discharging. A substantial number of active sites are generated during redox reactions by the unique surface morphology of the Sm2O3/Co3O4/rGO/NF composite (SCGN). The maximum specific capacity the SCGN material achieves is 3448 F g-1 for 1 A g-1 in a 6 mol L-1 KOH solution. Benefiting from its morphological structure, the prepared composite (SCGN) exhibits a high cyclability of 93.2% over 3000 charge-discharge cycles at 10 A g-1 and a coulombic efficiency of 97.4%. Additionally, the assembled SCGN//SCGN symmetric supercapacitors deliver a high energy density of 64 W h kg-1 with a power density of 300 W kg-1, which increases to an outstanding power density of 12 000 W kg-1 at 28.7 W h kg-1 and long cycle stability (80.9% capacitance retention after 30 000 cycles). These results suggest that the manufactured SCGN electrodes could be viable active electrode materials for electrochemical supercapacitors.

2.
Artículo en Inglés | MEDLINE | ID: mdl-37393215

RESUMEN

With industrialization and urbanization, China faces enormous challenges from energy security and environmental issues. To address these challenges, it is imperative to establish a green accounting system for economic growth and to measure the uncertainty of China's green GDP (GGDP) growth from a risk management perspective. With this in mind, we follow the idea of growth-at-risk (GaR) to propose the concept of green GaR (GGaR) and extend it to the mixed-frequency data environment. Specifically, we first measure China's annual GGDP using the System of Environmental Economic Accounting (SEEA), then construct China's monthly green financial index by a mixed-frequency dynamic factor model (MF-DFM), and finally monitor China's GGaR from 2008M1 to 2021M12 with the mixed data sampling-quantile regression (MIDAS-QR) method. The main findings are as follows: First, the proportion of China's GGDP to traditional GDP gradually increases from 81.97% in 2008 to 89.34% in 2021, which illustrates that the negative environmental externalities caused by China's economic growth are gradually decreasing. Second, the high-frequency GGaR has favorable predictive performance and is significantly superior to the common-frequency GGaR at most quantiles. Third, the high-frequency GGaR has good nowcasting performance, and its 90% and 95% confidence intervals include true value for all prediction horizons. Furthermore, it can provide early warning of economic downturns through probability density prediction. Overall, our main contribution lies in constructing a quantitative assessment and high-frequency monitoring of China's GGDP growth risk, which provides an effective tool for investors and companies to predict risk, and a reference for the Chinese government to better formulate sustainable development strategies.

3.
J Mater Chem B ; 11(27): 6290-6295, 2023 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-37376820

RESUMEN

Glioma is a highly challenging human malignancy and conventional drugs typically exhibit low blood-brain barrier (BBB) permeability as well as poor tumor targeting. To complicate matters further, recent advances in research on oncology have highlighted the dynamic and complex cellular networks within the immunosuppressive tumor microenvironment (TME) that complicate glioma treatment. Therefore, precise and efficient targeting of tumor tissue, whilst reversing immunosuppression, may provide an ideal strategy for the treatment of gliomas. Here, by using the "one-bead-one-component" combinatorial chemistry approach, we designed and screened a peptide that can specifically target brain glioma stem cells (GSCs), which was further engineered into glycopeptide-functionalized multifunctional micelles. We demonstrated that the micelles can carry DOX and effectively penetrate the BBB to achieve targeted killing of glioma cells. Meanwhile, mannose confers a unique tumor immune microenvironment modulating function to the micelles, which can activate the anti-tumor immune response function of tumor-associated macrophages and is expected to be further applied in vivo. This study highlights that glycosylation modification of targeted peptides specific to cancer stem cells (CSCs) may serve as an effective tool to improve the therapeutic outcome of brain tumor patients.


Asunto(s)
Neoplasias Encefálicas , Glioma , Humanos , Glicopéptidos , Micelas , Línea Celular Tumoral , Glioma/tratamiento farmacológico , Neoplasias Encefálicas/tratamiento farmacológico , Péptidos/uso terapéutico , Microambiente Tumoral
4.
Materials (Basel) ; 16(4)2023 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-36837323

RESUMEN

A 3D hierarchical spherical honeycomb-like composite electrode materialof neodymium oxide (Nd2O3), cobalt tetraoxide (Co3O4), and reduced graphene oxide (rGO) on nickel foam (named as Nd2O3/Co3O4/rGO/NF) were successfully fabricated by combining the hydrothermal synthesis method and the annealing process. Nickel foam with a three-dimensional spatial structure was used as the growth substrate without the use of any adhesives. The Nd2O3/Co3O4/rGO/NF composite has outstanding electrochemical performance and can be used directly as an electrode material for supercapacitors (SCs). By taking advantage of the large specific surface area of the electrode material, it effectively slows down the volume expansion of the active material caused by repeated charging and discharging processes, improves the electrode performance in terms of electrical conductivity, and significantly shortens the electron and ion transport paths. At a 1 A/g current density, the specific capacitance reaches a maximum value of 3359.6 F/g. A specific capacitance of 440.4 F/g with a current density of 0.5A/g is still possible from the built symmetric SCs. The capacitance retention rate is still 95.7% after 30,000 cycles of testing at a high current density of 10 A/g, and the energy density is 88.1 Wh/kg at a power density of 300 W/kg. The outcomes of the experiment demonstrate the significant potential and opportunity for this composite material to be used as an electrode material for SCs.

5.
Front Immunol ; 13: 903882, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35711455

RESUMEN

Lung cancer has the highest mortality rate among human cancers, and the majority of deaths result from metastatic spread. The tumor microenvironment plays an important role in suppressing the immune surveillance and elimination of tumor cells. A few studies have reported the presence of CD45+EpCAM+ double-positive cells in cancer, but the underlying mechanism remains unclear with respect to how these cells originate and their function in cancer biology. In this study, we analyzed 25 lung tumor samples. We confirmed the presence of CD45+EpCAM+ cells in lung cancer, and these cells exhibited higher apoptosis than CD45+EpCAM- cells. Using co-culture of lung cancer cell-derived exosomes with healthy donor peripheral blood mononuclear cells, we recapitulated CD45+EpCAM+ cell formation and increased apoptosis that occurs in patients with primary lung cancer. Further analysis suggested that microRNAs in lung cancer cell-derived exosomes may alter the gene expression profile of CD45+EpCAM+ cells, resulting in elevated TP53 expression and increased apoptosis. To our knowledge, this is the first report of cancer cell-derived exosomes that can inhibit the immune system by promoting immune cell apoptosis.


Asunto(s)
Exosomas , Neoplasias Pulmonares , Apoptosis , Molécula de Adhesión Celular Epitelial , Exosomas/metabolismo , Humanos , Leucocitos Mononucleares/metabolismo , Neoplasias Pulmonares/metabolismo , Microambiente Tumoral
6.
RSC Adv ; 12(24): 15508-15516, 2022 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-35685182

RESUMEN

Supercapacitors are energy storage devices with the advantage of rapid charging and discharging, which need a higher specific capacitance and superior cycling stability. Hence, a composite material consisting of RuCo2O4 and reduced graphene oxide with a nanowire network structure was synthesized on nickel foam using a one-step hydrothermal method and annealing process. The nanowire network structure consists of nanowires with gaps that provide more active sites for electrochemical reactions and shorten the diffusion path of electrolyte ions. The prepared electrodes exhibit outstanding electrochemical performance with 2283 F g-1 at 1 A g-1. When the current density is 10 A g-1, the specific capacitance of the electrodes is 1850 F g-1, which maintains 81% of the initial specific capacitance. In addition, the prepared electrodes have a long-term cycling life with capacitance retention of 92.60% after 3000 cycles under the current density of 10 A g-1. The composite material is a promising electrode material for high-performance supercapacitors.

7.
ACS Omega ; 7(5): 4267-4276, 2022 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-35155919

RESUMEN

As technology continues to develop, electronic devices are becoming ever more integrated. The high level of integration results in a higher volume of calculations and higher heat generation. Metal materials have always been good conductors of heat and are commonly used in thermally conductive devices. However, the thermal conductivity of metallic materials decreases at elevated temperatures. Therefore, it is reasonable to develop new composite materials as thermal conductivity materials. In the experiments, a novel composite material with a sandwich structure has been designed. The material uses metallic aluminum (Al) as a substrate. Then, the metallic aluminum was soaked in a polydopamine (PDA) solution. Graphene (G) on the surface of the material was then enriched using an electrophoretic method. The material was removed and annealed to form the G-PDA-Al composite. According to the measurement, the thermal conductivity of the material is 492 W·m-1·K-1, which means ultrahigh thermal conductivity. Elongation experiments were carried out, and they increased the strength of the material by 12.4%. The formation of the material was then analyzed. The construction of the material was then carefully examined. The surface morphology, elemental composition, and structures were investigated by using scanning electron microscopy equipped by a scanning electron microscope, X-ray diffraction, infrared spectroscopy, and X-ray photoelectron spectroscopy. Differences from ordinary thermal materials were obtained based on calculations. A flexible thermal conductor was fabricated by using this material. The device can reduce the spontaneous combustion of ternary lithium batteries.

8.
RSC Adv ; 11(55): 34676-34687, 2021 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-35494770

RESUMEN

A composite material of graphene (G) and polydopamine (PDA) on a copper (Cu) substrate (G/PDA@Cu) was fabricated successfully by sequential immersion deposition in a dopamine solution and an aqueous graphene oxide suspension before annealing. Optimum preparation conditions were explored by the orthogonal experimental method. The morphology and chemical composition of G/PDA@Cu were studied systematically by a series of characterization techniques. The thermal-conductive performance was evaluated by a laser flash thermal analyser. The thermal conductivity of G/PDA@Cu was 519.43 W m-1 K-1, which is ultrahigh and 30.50% higher than that of the Cu substrate. The adhesion force between G/PDA and the Cu substrate was 4.18 mN, which means that G bonds to the Cu substrate tightly. The model simulation also showed that G/PDA@Cu exhibits excellent thermal conductivity, allowing it to play a significant role in the thermal management of advanced electronic chips. The thermal-conductive devices using this material were prepared for practical applications.

9.
Nanoscale Adv ; 1(8): 3086-3094, 2019 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-36133593

RESUMEN

In this study, the controllable preparation of ZnCo2O4 with different morphologies in a reaction system and the orderly weaving of these morphologies into special structures was demonstrated, which might be impossible to achieve using other methods; herein, we successfully prepared a dual-morphology ZnCo2O4/N-doped reduced graphene oxide/Ni foam substrate (ZNGN) electrode by ultrasonic processing, a one-step hydrothermal method and a subsequent annealing process for high-performance supercapacitors. At first, ZnCo2O4 nanosheet orderly formed a honeycomb structure on the surface of Ni foam (NF); this improved the redox surface area of the electrode; then, feather-like ZnCo2O4 was evenly distributed over the honeycomb structure, playing the role of containment and fixation to provide space for material volume expansion during charging and discharging. The electrochemical test showed that the maximum capacitance of the ZNGN electrode was 1600 F g-1 (960C g-1) at the current density of 1 A g-1 in a 6 M KOH solution. Moreover, the asymmetric supercapacitor ZNGN//activated carbon (ZNGN//AC) displayed the excellent energy density of 66.1 W h kg-1 at the power density of 701 W kg-1. Compared with the capacitance (233.3 F g-1 and 326.6C g-1) when ZNGN//AC was fully activated at 4 A g-1, there was almost no loss in capacitance after 2000 charge-discharge cycles, and a 94% capacitance retention was achieved after 5000 cycles. Thus, this excellent electrochemical property highlights the potential application of the dual-morphology ZnCo2O4 electrode in supercapacitors.

10.
J Colloid Interface Sci ; 525: 76-85, 2018 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-29684733

RESUMEN

Inspired by the lotus effect and water-repellent properties of water striders' legs, superhydrophobic surfaces have been intensively investigated from both fundamental and applied perspectives for daily and industrial applications. Various techniques are available for the fabrication of artificial superoleophilic/superhydrophobic (SS). However, most of these techniques are tedious and often require hazardous or expensive equipment, which hampers their implementation for practical applications. In the present work, we used a versatile and straightforward technique based on polymer drop-casting for the preparation SS materials that can be implemented on any substrate. High density polyethylene (HDPE) SS coatings were prepared on different substrates (glass, copper mesh and polyurethane (PU) sponge) by drop casting the parent polymer xylene-ethanol solution at room temperature. All the substrates exhibited a superhydrophobic behavior with a water contact angle (WCA) greater than 150°. Furthermore, the corrosion resistance, stability, self-cleaning property, and water/oil separation of the developed materials were also assessed. While copper mesh and PU sponge exhibited good ability for oil and organic solvents separation from water, the HDPE-functionalized PU sponge displayed good adsorption capacity, 32-90 times the weight of adsorbed substance vs. the weight of adsorbent.

11.
Sci Rep ; 6: 29548, 2016 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-27405888

RESUMEN

Gene regulatory networks involved in flowering time and photoperiodic responses in legumes remain unknown. Although the major maturity gene E1 has been successfully deciphered in soybean, knowledge on the functional conservation of this gene is limited to a certain extent to E1 homologs in legumes. The ectopic expression of Phvul.009G204600 (PvE1L), an E1 homolog from common bean, delayed the onset of flowering in soybean. By contrast, the ectopic expression of Medtr2g058520 (MtE1L) from Medicago truncatula did not affect the flowering of soybean. Characterization of the late-flowering mte1l mutant indicated that MtE1L promoted flowering in Medicago truncatula. Moreover, all transgenic E1, PvE1L and MtE1L soybean lines exhibited phenotypic changes in terms of plant height. Transgenic E1 or PvE1L plants were taller than the wild-type, whereas transgenic MtE1L plants produced dwarf phenotype with few nodes and short internode. Thus, functional conservation and diversification of E1 family genes from legumes in the regulation of flowering and plant growth may be associated with lineage specification and genomic duplication.


Asunto(s)
Fabaceae/genética , Glycine max/crecimiento & desarrollo , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente/crecimiento & desarrollo , Secuencia de Aminoácidos , Secuencia Conservada , Fabaceae/crecimiento & desarrollo , Flores/genética , Flores/crecimiento & desarrollo , Modelos Moleculares , Familia de Multigenes , Fotoperiodo , Filogenia , Proteínas de Plantas/química , Estructura Secundaria de Proteína , Glycine max/genética
12.
Planta ; 243(3): 623-33, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26586176

RESUMEN

MAIN CONCLUSION: We provide evidence that AtDBP1 promotes flowering by regulating the transcript levels of several important integrators and floral meristem identity genes, including FLC, CO, SOC1, LFY, FT and FD. DNA-binding protein phosphatases (DBP) which exhibit both sequence specific DNA-binding and protein phosphatase 2C activities are important regulators that are involved in both the transcriptional and post-translational regulations. DBP factors are known to mediate susceptibility to potyviruses; however, whether they are involved in other processes is still unclear. In this study, under both long day (LD) and short day conditions, AtDBP1 overexpressing plants displayed early flowering, while the knock out mutants, atdbp1, exhibited a delay in flowering relative to the wild-type plants; both the overexpressing lines and atdbp1 mutants remained photoperiodic sensitive, indicating that AtDBP1 was involved in the autonomous pathway. AtDBP1 does not respond to vernalization at transcript level, and both AtDBP1 overexpressing plants and atdbp1 mutants remain responsive to vernalization, indicating that AtDBP1 may not be directly involved in vernalization. Real-time PCR analysis showed that AtDBP1 can suppress FLOWERING LOCUC C (FLC) expression, a key integrator of the autonomous and vernalization pathways, and enhance the expression levels of CONSTANS and FLOWERING LOCUC T, key regulators of the LD pathway. Furthermore, expression of floral meristem identity genes including SUPPRESSOR OF OVEREXPRESSION OF CO 1, LEAFY and FD was also promoted in AtDBP1 overexpressing plants. AtDBP1 transcription can be detected in root, leaf, stem, flower and silique. AtDBP1-GFP and YFP-AtDBP1 fusion protein were localized in the cytosol and nucleus. Our results provide the evidence demonstrating the effective role of AtDBP1 for flowering time regulation and report a novel function of DBP factors in planta besides in plant defense.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Proteínas de Unión al ADN/metabolismo , Fosfoproteínas Fosfatasas/metabolismo , Arabidopsis/crecimiento & desarrollo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Unión al ADN/genética , Flores/genética , Flores/crecimiento & desarrollo , Flores/metabolismo , Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Meristema/genética , Meristema/crecimiento & desarrollo , Meristema/metabolismo , Mutación , Fosfoproteínas Fosfatasas/genética , Fotoperiodo , Hojas de la Planta/genética , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas/genética
13.
PLoS One ; 10(8): e0135909, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26275311

RESUMEN

Although four maturity genes, E1 to E4, in soybean have been successfully cloned, their functional mechanisms and the regulatory network of photoperiodic flowering remain to be elucidated. In this study, we investigated how the diurnal expression pattern of the E1 gene is related to photoperiodic length; and to what extent allelic variation in the B3-like domain of the E1 gene is associated with flowering time phenotype. The bimodal expression of the E1 gene peaked first at around 2 hours after dawn in long-day condition. The basal expression level of E1 was enhanced by the long light phase, and decreased by duration of dark. We identified a 5bp (3 SNP and 2-bp deletion) mutation, referred to an e1-b3a, which occurs in the middle of B3 domain of the E1 gene in the early flowering cultivar Yanhuang 3. Subcellular localization analysis showed that the putative truncated e1-b3a protein was predominately distributed in nuclei, indicating the distribution pattern of e1-b3a was similar to that of E1, but not to that of e1-as. Furthermore, genetic analysis demonstrated allelic variations at the E1 locus significantly underlay flowering time in three F2 populations. Taken together, we can conclude the legume specific E1 gene confers some special features in photoperiodic control of flowering in soybean. Further characterization of the E1 gene will extend our understanding of the soybean flowering pathway in soybean.


Asunto(s)
Alelos , Flores , Regulación de la Expresión Génica de las Plantas/fisiología , Genes de Plantas/fisiología , Variación Genética , Glycine max , Fotoperiodo , Flores/genética , Flores/metabolismo , Glycine max/genética , Glycine max/metabolismo
14.
Phys Chem Chem Phys ; 17(16): 10871-80, 2015 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-25821030

RESUMEN

Superhydrophobic coatings on a copper substrate are grown via electrodeposition followed by thermal annealing. The influence of the deposition potential, zinc ion concentration, deposition time, annealing temperature and annealing time on the wetting properties was systematically investigated. The coating electrodeposited at -1.35 V for 25 min and annealed at 190 °C for 60 min exhibited excellent superhydrophobicity with a contact angle as high as 170 ± 2° and a sliding angle of almost 0°. The water drop can fully bounce as a balloon when impinging such a solid surface, exhibiting excellent non-sticking properties. By adopting various characterization methods, it was demonstrated that the as-prepared superhydrophobic surfaces also exhibited properties of anticorrosion, antiabrasion, long-term stability and durability and large buoyancy force, which offer an effective strategy and promising industrial applications for fabricating superhydrophobic surfaces on various metallic materials.

15.
Dalton Trans ; 44(4): 1601-11, 2015 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-25428510

RESUMEN

A facile and template-free solvothermal method was developed for the synthesis of microspheric g-C3N4/Bi2MoO6 photocatalysts. The obtained g-C3N4/Bi2MoO6 composites were characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), X-ray photo-electron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), and ultraviolet-visible diffuse reflection spectroscopy (DRS). The XRD, FTIR, and HRTEM characterization results confirmed the formation of heterojunction structures at the interfaces of g-C3N4 and Bi2MoO6. The DRS results showed that the absorption edges of g-C3N4/Bi2MoO6 composites were red shifted in the visible light region with the increase of g-C3N4 content. The SEM and TEM images revealed that the composites exhibited a microsphere-like morphology and were composed of smaller nanoplates. The elemental mapping images revealed that g-C3N4 and Bi2MoO6 nanoflakes uniformly assembled together to form hierarchical flowers. Compared with pure g-C3N4 and Bi2MoO6, the as-prepared samples exhibited superior photocatalytic activity towards the degradation of dyes (Rhodamine B and Methyl blue) under visible light irradiation. The enhanced photocatalytic activity of g-C3N4/Bi2MoO6 composites could be attributed to their strong visible light absorption, the high migration efficiency of photo-induced carriers, and the interfacial electronic interaction. The electrochemical impedance spectroscopy (EIS) confirmed that the interface charge separation efficiency was greatly improved by coupling g-C3N4 with Bi2MoO6. It was also confirmed that the photo-degradation of dye molecules is mainly attributed to the oxidizing ability of the generated holes (h(+)) and partly to the oxidizing ability of ·O2(-) and ·OH radicals.

16.
PLoS One ; 9(5): e97636, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24830458

RESUMEN

The time to flowering and maturity are ecologically and agronomically important traits for soybean landrace and cultivar adaptation. As a typical short-day crop, long day conditions in the high-latitude regions require soybean cultivars with photoperiod insensitivity that can mature before frost. Although the molecular basis of four major E loci (E1 to E4) have been deciphered, it is not quite clear whether, or to what degree, genetic variation and the expression level of the four E genes are associated with the time to flowering and maturity of soybean cultivars. In this study, we genotyped 180 cultivars at E1 to E4 genes, meanwhile, the time to flowering and maturity of those cultivars were investigated at six geographic locations in China from 2011 to 2012 and further confirmed in 2013. The percentages of recessive alleles at E1, E2, E3 and E4 loci were 38.34%, 84.45%, 36.33%, and 7.20%, respectively. Statistical analysis showed that allelic variations at each of four loci had a significant effect on flowering time as well as maturity. We classified the 180 cultivars into eight genotypic groups based on allelic variations of the four major E loci. The genetic group of e1-nf representing dysfunctional alleles at the E1 locus flowered earliest in all the geographic locations. In contrast, cultivars in the E1E2E3E4 group originated from the southern areas flowered very late or did not flower before frost at high latitude locations. The transcriptional abundance of functional E1 gene was significantly associated with flowering time. However, the ranges of time to flowering and maturity were quite large within some genotypic groups, implying the presence of some other unknown genetic factors that are involved in control of flowering time or maturity. Known genes (e.g. E3 and E4) and other unknown factors may function, at least partially, through regulation of the expression of the E1 gene.


Asunto(s)
Flores/fisiología , Regulación de la Expresión Génica de las Plantas , Variación Genética , Glycine max/genética , Sitios de Carácter Cuantitativo , Alelos , China , Flores/genética , Genes de Plantas , Genotipo , Geografía , Modelos Lineales , Fenotipo , Fotoperiodo , Glycine max/fisiología , Temperatura , Tiempo (Meteorología)
17.
PLoS One ; 9(2): e89030, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24586488

RESUMEN

The major maturity gene E1 has the most prominent effect on flowering time and photoperiod sensitivity of soybean, but the pathway mediated by E1 is largely unknown. Here, we found the expression of GmFT4, a homolog of Flowering Locus T, was strongly up-regulated in transgenic soybean overexpressing E1, whereas expression of flowering activators, GmFT2a and GmFT5a, was suppressed. GmFT4 expression was strongly up-regulated by long days exhibiting a diurnal rhythm, but down-regulated by short days. Notably, the basal expression level of GmFT4 was elevated when transferred to continous light, whereas repressed when transferred to continuous dark. GmFT4 was primarily expressed in fully expanded leaves. Transcript abundance of GmFT4 was significantly correlated with that of functional E1, as well as flowering time phenotype in different cultivars. Overexpression of GmFT4 delayed the flowering time in transgenic Arabidopsis. Taken together, we propose that GmFT4 acts downstream of E1 and functions as a flowering repressor, and the balance of two antagonistic factors (GmFT4 vs GmFT2a/5a) determines the flowering time of soybean.


Asunto(s)
Flores/genética , Glycine max/genética , Proteínas de Plantas/genética , Proteínas Represoras/genética , Factores de Transcripción/genética , Secuencia de Aminoácidos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Regulación de la Expresión Génica de las Plantas , Datos de Secuencia Molecular , Filogenia , Plantas Modificadas Genéticamente , Homología de Secuencia
18.
ScientificWorldJournal ; 2013: 281367, 2013 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-24311973

RESUMEN

Soybean is a model plant for photoperiodism as well as for symbiotic nitrogen fixation. However, a rather low efficiency in soybean transformation hampers functional analysis of genes isolated from soybean. In comparison, rapid development and progress in flowering time and photoperiodic response have been achieved in Arabidopsis and rice. As the soybean genomic information has been released since 2008, gene cloning and functional genomic studies have been revived as indicated by successfully characterizing genes involved in maturity and nematode resistance. Here, we review some major achievements in the cloning of some important genes and some specific features at genetic or genomic levels revealed by the analysis of functional genomics of soybean.


Asunto(s)
Clonación Molecular , Resistencia a la Enfermedad/fisiología , Genes de Plantas/fisiología , Genómica , Glycine max/genética , Fotoperiodo , Glycine max/metabolismo
19.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 21(1): 150-4, 2013 Feb.
Artículo en Chino | MEDLINE | ID: mdl-23484710

RESUMEN

This study was aimed to investigate the radioprotective effects of recombinant human interleukin-12 (rhIL-12) on monkey hematopoietic system, and to provide experimental evidence for future clinical prophylaxis and treatment for patients who suffered from acute radiation syndrome. In in vitro study, the effect of rhIL-12 in different concentrations (0, 1, 5, 25, 125 and 625 ng/ml) on colony forming capacity of human or monkey bone marrow-derived mononuclear cells was examined in methylcellulose H4434 medium. In in vivo study, the acute radiation syndrome model was established in 11 Rhesus monkeys which received lethal total body irradiation by 6 Gy (60)Co γ in single time irradiation. The irradiated monkeys were randomly divided into 3 subgroups: control group (n = 4) which received subcutaneous PBS injection, rhIL-12 single-dose group (n = 3) which received subcutaneous single injection of rhIL-12 (4 µg/kg) at 2 h after irradiation, and multiple-dose group (n = 4) which received subcutaneous injection of rhIL-12 (1 µg/kg per injection) at 2 h, day 3, 6 and 9 after irradiation respectively. Peripheral blood cells were counted before and after irradiation every other day. The survival status of animals were observed daily. In vitro test results showed that different concentrations of rhIL-12 obviously promoted human and healthy monkeys' bone marrow mononuclear cells to form various hematopoietic progenitor cell colonies, especial CFU-E and CFU-GM. All animals in control group died within 22 d after lethal total body irradiation, average survival time was (20.3 ± 1.2) d. Only one monkey in multiple-dose group died due to anemia on day 17. All monkeys in single-dose group survived. Compared with control group, rhIL-12-administrated monkeys' white blood cell count, hemoglobin level, platelet and reticulocyte counts showed faster recovery from high dose radiation. It is concluded that the rhIL-12 treatment can promote the bone marrow hematopoietic stem/progenitor cell colony formation in vitro and protect lethally-irradiated monkeys. There is an obvious therapeutic effect of rhIL-12 on monkeys suffered from bone marrow failure caused by severe acute radiation exposure.


Asunto(s)
Células Madre Hematopoyéticas/efectos de los fármacos , Interleucina-12/farmacología , Protectores contra Radiación/farmacología , Animales , Células de la Médula Ósea/citología , Células de la Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/efectos de la radiación , Células Cultivadas , Células Madre Hematopoyéticas/efectos de la radiación , Humanos , Macaca mulatta , Proteínas Recombinantes de Fusión/farmacología
20.
Proc Natl Acad Sci U S A ; 109(32): E2155-64, 2012 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-22619331

RESUMEN

The complex and coordinated regulation of flowering has high ecological and agricultural significance. The maturity locus E1 has a large impact on flowering time in soybean, but the molecular basis for the E1 locus is largely unknown. Through positional cloning, we delimited the E1 locus to a 17.4-kb region containing an intron-free gene (E1). The E1 protein contains a putative bipartite nuclear localization signal and a region distantly related to B3 domain. In the recessive allele, a nonsynonymous substitution occurred in the putative nuclear localization signal, leading to the loss of localization specificity of the E1 protein and earlier flowering. The early-flowering phenotype was consistently observed in three ethylmethanesulfonate-induced mutants and two natural mutations that harbored a premature stop codon or a deletion of the entire E1 gene. E1 expression was significantly suppressed under short-day conditions and showed a bimodal diurnal pattern under long-day conditions, suggesting its response to photoperiod and its dominant effect induced by long day length. When a functional E1 gene was transformed into the early-flowering cultivar Kariyutaka with low E1 expression, transgenic plants carrying exogenous E1 displayed late flowering. Furthermore, the transcript abundance of E1 was negatively correlated with that of GmFT2a and GmFT5a, homologues of FLOWERING LOCUS T that promote flowering. These findings demonstrated the key role of E1 in repressing flowering and delaying maturity in soybean. The molecular identification of the maturity locus E1 will contribute to our understanding of the molecular mechanisms by which a short-day plant regulates flowering time and maturity.


Asunto(s)
Flores/fisiología , Regulación de la Expresión Génica de las Plantas/genética , Genes de Plantas/genética , Sitios Genéticos/genética , Glycine max/crecimiento & desarrollo , Glycine max/genética , Fotoperiodo , Secuencia de Bases , Southern Blotting , Mapeo Cromosómico , Cromosomas Artificiales Bacterianos/genética , Clonación Molecular , Análisis por Conglomerados , Cartilla de ADN/genética , Metanosulfonato de Etilo , Flores/genética , Variación Genética , Modelos Genéticos , Datos de Secuencia Molecular , Mutagénesis , Filogenia , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN
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