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1.
Environ Sci Technol ; 58(14): 6170-6180, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38501927

RESUMO

As human society has advanced, nuclear energy has provided energy security while also offering low carbon emissions and reduced dependence on fossil fuels, whereas nuclear power plants have produced large amounts of radioactive wastewater, which threatens human health and the sustainability of water resources. Here, we demonstrate a hydrate-based desalination (HBD) technology that uses methane as a hydrate former for freshwater recovery and for the removal of radioactive chemicals from wastewater, specifically from Cs- and Sr-containing wastewater. The complete exclusion of radioactive ions from solid methane hydrates was confirmed by a close examination using phase equilibria, spectroscopic investigations, thermal analyses, and theoretical calculations, enabling simultaneous freshwater recovery and the removal of radioactive chemicals from wastewater by the methane hydrate formation process described in this study. More importantly, the proposed HBD technology is applicable to radioactive wastewater containing Cs+ and Sr2+ across a broad concentration range of low percentages to hundreds of parts per million (ppm) and even subppm levels, with high removal efficiency of radioactive chemicals. This study highlights the potential of environmentally sustainable technologies to address the challenges posed by radioactive wastewater generated by nuclear technology, providing new insights for future research and development efforts.


Assuntos
Césio , Águas Residuárias , Humanos , Estrôncio , Água Doce , Metano/química
2.
J Exp Bot ; 72(12): 4254-4268, 2021 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-33831183

RESUMO

We previously identified a cluster of yield-related quantitative trait loci (QTLs) including plant height in CR4379, a near-isogenic line from a cross between Oryza sativa spp. japonica cultivar 'Hwaseong' and the wild relative Oryza rufipogon. Map-based cloning and transgenic approaches revealed that APX9, which encodes an l-ascorbate peroxidase 4, is associated with this cluster. A 3 bp InDel was observed leading to the addition of a valine in Hwaseong compared with O. rufipogon. APX9-overexpressing transgenic plants in the Hwaseong background were taller than Hwaseong. Consistent with these results, APX9 T-DNA insertion mutants in the japonica cultivar Dongjin were shorter. These results confirm that APX9 is the causal gene for the QTL cluster. Sequence analysis of APX9 from 303 rice accessions revealed that the 3 bp InDel clearly differentiates japonica (APX9HS) and O. rufipogon (APX9OR) alleles. indica accessions shared both alleles, suggesting that APX9HS was introgressed into indica followed by crossing. The finding that O. rufipogon accessions with different origins carry APX9OR suggests that the 3 bp insertion was specifically selected in japonica during its domestication. Our findings demonstrate that APX9 acts as a major regulator of plant development by controlling a valuable suite of agronomically important traits in rice.


Assuntos
Oryza , Locos de Características Quantitativas , Ascorbato Peroxidases , Cruzamentos Genéticos , Oryza/genética , Fenótipo , Locos de Características Quantitativas/genética
3.
Int J Mol Sci ; 21(5)2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-32131496

RESUMO

Leaf senescence is the final stage of plant development. Many internal and external factors affect the senescence process in rice (Oryza sativa L.). In this study, we identified qCC2, a major quantitative trait locus (QTL) for chlorophyll content using a population derived from an interspecific cross between O. sativa (cv. Hwaseong) and Oryza grandiglumis. The O. grandiglumis allele at qCC2 increased chlorophyll content and delayed senescence. GW2 encoding E3 ubiquitin ligase in the qCC2 region was selected as a candidate for qCC2. To determine if GW2 is allelic to qCC2, a gw2-knockout mutant (gw2-ko) was examined using a dark-induced senescence assay. gw2-ko showed delayed leaf senescence in the dark with down-regulated expression of senescence-associated genes (SAGs) and chlorophyll degradation genes (CDGs). The association of the GW2 genotype with the delayed senescence phenotype was confirmed in an F2 population. RNA-seq analysis was conducted to investigate 30-day-old leaf transcriptome dynamics in Hwaseong and a backcross inbred line-CR2002-under dark treatment. This resulted in the identification of genes involved in phytohormone signaling and associated with senescence. These results suggested that transcriptional regulation was associated with delayed senescence in CR2002, and RING-type E3 ubiquitin ligase GW2 was a positive regulator of leaf senescence in rice.


Assuntos
Clorofila/metabolismo , Oryza/genética , Folhas de Planta/genética , Proteínas de Plantas/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Clorofila/genética , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Folhas de Planta/metabolismo , Folhas de Planta/efeitos da radiação , Proteínas de Plantas/genética , Locos de Características Quantitativas , Luz Solar , Transcriptoma , Ubiquitina-Proteína Ligases/genética
4.
Molecules ; 24(16)2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31395847

RESUMO

The thermal properties of organic-inorganic (CH3NH3)2CoBr4 crystals were investigated using differential scanning calorimetry and thermogravimetric analysis. The phase transition and partial decomposition temperatures were observed at 460 K and 572 K. Nuclear magnetic resonance (NMR) chemical shifts depend on the local field at the site of the resonating nucleus. In addition, temperature-dependent spin-lattice relaxation times (T1ρ) were measured using 1H and 13C magic angle spinning NMR to elucidate the paramagnetic interactions of the (CH3NH3)+ cations. The shortening of 1H and 13C T1ρ of the (CH3NH3)2CoBr4 crystals are due to the paramagnetic Co2+ effect. Moreover, the physical properties of (CH3NH3)2CoBr4 with paramagnetic ions and those of (CH3NH3)2CdBr4 without paramagnetic ions are reported and compared.


Assuntos
Compostos de Cálcio/química , Óxidos/química , Titânio/química , Varredura Diferencial de Calorimetria , Espectroscopia de Ressonância Magnética , Transição de Fase
5.
Physiol Plant ; 153(4): 525-37, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25220246

RESUMO

The R2R3-type protein IbMYB1 is a key regulator of anthocyanin biosynthesis in the storage roots of sweet potato [Ipomoea batatas (L.) Lam]. Previously, we demonstrated that IbMYB1 expression stimulated anthocyanin pigmentation in tobacco leaves and Arabidopsis. Here, we generated dual-pigmented transgenic sweet potato plants that accumulated high levels of both anthocyanins and carotenoids in a single sweet potato storage root. An orange-fleshed cultivar with high carotenoid levels was transformed with the IbMYB1 gene under the control of either the storage root-specific sporamin 1 (SPO1) promoter or the oxidative stress-inducible peroxidase anionic 2 (SWPA2) promoter. The SPO1-MYB transgenic lines exhibited higher anthocyanin levels in storage roots than empty vector control (EV) or SWPA2-MYB plants, but carotenoid content was unchanged. SWPA2-MYB transgenic lines exhibited higher levels of both anthocyanin and carotenoids than EV plants. Analysis of hydrolyzed anthocyanin extracts indicated that cyanidin and peonidin predominated in both overexpression lines. Quantitative reverse transcription-polymerase chain reaction analysis demonstrated that IbMYB1 expression in both IbMYB1 transgenic lines strongly induced the upregulation of several genes in the anthocyanin biosynthetic pathway, whereas the expression of carotenoid biosynthetic pathway genes varied between transgenic lines. Increased anthocyanin levels in transgenic plants also promoted the elevation of proanthocyanidin and total phenolic levels in fresh storage roots. Consequently, all IbMYB1 transgenic plants displayed much higher antioxidant activities than EV plants. In field cultivations, storage root yields varied between the transgenic lines. Taken together, our results indicate that overexpression of IbMYB1 is a highly promising strategy for the generation of transgenic plants with enhanced antioxidant capacity.


Assuntos
Antocianinas/metabolismo , Antioxidantes/metabolismo , Carotenoides/metabolismo , Ipomoea batatas/genética , Proteínas de Plantas/genética , Expressão Gênica , Ipomoea batatas/metabolismo , Especificidade de Órgãos , Oxirredução , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas/genética , Nicotiana/genética , Nicotiana/fisiologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
6.
Mol Biol Rep ; 41(10): 6957-66, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25030835

RESUMO

Metallothioneins (MTs) are cysteine-rich, low molecular weight, metal-binding proteins that are widely distributed in living organisms. Plants produce metal-chelating proteins such as MTs to overcome the toxic effects of heavy metals. We cloned three MT genes from sweetpotato leaves [Ipomoea batatas (L.) Lam.]. The three IbMT genes were classified according to their cysteine residue alignment into type 1 (IbMT1), type 2 (IbMT2), and type 3 (IbMT3). IbMT1 was the most abundantly transcribed MT. It was predominantly expressed in leaves, roots, and callus. IbMT2 transcript was detected only in stems and fibrous roots, whereas IbMT3 was strongly expressed in leaves and stems. The IbMT expression profiles were investigated in plants exposed to heavy metals and abiotic stresses. The levels of IbMT1 expression were strongly elevated in response to Cd and Fe, and moderately higher in response to Cu. The IbMT3 expression pattern in response to heavy metals was similar to that of IbMT1. Exposure to abiotic stresses such as methyl viologen (MV; paraquat), NaCl, polyethylene glycol (PEG), and H2O2 up-regulated IbMT expression; IbMT1 responded strongly to MV and NaCl, whereas IbMT3 was induced by low temperature and PEG. Transgenic Escherichia coli overexpressing IbMT1 protein exhibited results suggest that IbMT could be a useful tool for engineering plants with enhanced tolerance to environmental stresses and heavy metals.


Assuntos
Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ipomoea batatas/efeitos dos fármacos , Ipomoea batatas/genética , Metalotioneína/genética , Metais Pesados/toxicidade , Estresse Fisiológico/genética , Adaptação Biológica/genética , Sequência de Aminoácidos , Células Cultivadas , Escherichia coli/genética , Escherichia coli/metabolismo , Ipomoea batatas/classificação , Metalotioneína/química , Dados de Sequência Molecular , Especificidade de Órgãos/genética , Filogenia , Reguladores de Crescimento de Plantas/farmacologia , Plantas Geneticamente Modificadas , Alinhamento de Sequência
7.
Mol Biol Rep ; 41(12): 8137-48, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25213547

RESUMO

Lycopene ß-cyclase (LCY-ß) is a key enzyme involved in the synthesis of α- and ß-branch carotenoids such as α-carotene and ß-carotene through the cyclization of lycopene. IbLCY-ß had a length of 1,506 bp and approximately 80 % nucleotide sequence identity with that of tomato LCY-ß. IbLCY-ß was strongly expressed in leaves, and expression was enhanced by salt-stress and osmotic-stress conditions. To characterize the LCY-ß gene (IbLCY-ß) of sweetpotato (Ipomoea batatas), it was isolated and transformed into calli of white-fleshed sweetpotato using an IbLCY-ß-RNAi vector. Transgenic IbLCY-ß-RNAi calli had yellow to orange color and higher antioxidant activity compared to that of white, nontransgenic (NT) calli. Transgenic cells had significantly higher contents of total carotenoids, although lycopene was not detected in transgenic or NT cells. All transgenic calli had strongly activated expression of carotenoid biosynthetic genes such as ß-carotene hydroxylases (CHY-ß), cytochrome P450 monooxygenases (P450), and carotenoid cleavage dioxigenase 1 (CCD1). Transgenic cells exhibited less salt-induced oxidative-stress damage compared to that of NT cells, and also had greater tolerance for polyethylene glycol (PEG)-mediated drought compared to that of NT cells, due to the higher water content and reduced malondialdehyde (MDA) content. The abscisic acid content was also higher in transgenic cells. These results show that a study of IbLCY-ß can facilitate understanding of the carotenoid biosynthetic pathway in sweetpotato. IbLCY-ß could be useful for developing transgenic sweetpotato enriched with nutritional carotenoids and with greater tolerance to abiotic stresses.


Assuntos
Carotenoides/biossíntese , Regulação para Baixo , Liases Intramoleculares/genética , Liases Intramoleculares/metabolismo , Ipomoea batatas/genética , Ácido Abscísico/metabolismo , Regulação da Expressão Gênica de Plantas , Ipomoea batatas/enzimologia , Licopeno , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/enzimologia , Plantas Geneticamente Modificadas/genética , Polietilenoglicóis/farmacologia , Tolerância ao Sal , Estresse Fisiológico
8.
RSC Adv ; 14(19): 13445-13451, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38660532

RESUMO

The NMR chemical shifts, linewidths, spin-lattice relaxation times in the rotating system T1ρ, and spin-lattice relaxation times in the laboratory system T1 were evaluated for the perovskite-type N(CH3)4CdBr3 crystal, aiming to understand the changes in the structural geometry and molecular dynamics from phase I to phase II. From the temperature-dependence of the 1H, 13C, 14N, and 113Cd NMR chemical shifts, the structural geometry underwent a continuous change, without anomalous changes around (TC = 390 K). However, the linewidths in phase I were narrower than those in phase II, indicating that the motional averaging effects were caused by the rapid rotation of the N(CH3)4 group. Sudden changes in T1 and T1ρ were observed near TC, for which the activation energy Ea in phase I was approximately 12 times larger than that in phase II; the small Ea values in phase II indicate a large degree of freedom for the methyl group and CdBr6 octahedra, whereas the large Ea in phase I was primarily attributed to the overall N(CH3)4 and the 113Cd in the CdBr6 groups. Consequently, the phase transition mechanisms of N(CH3)4CdBr3 are related to reorientation of the N(CH3)4 group and the arrangement of the CdBr6 groups.

9.
Plant Cell ; 22(7): 2237-52, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20647347

RESUMO

Plants strictly regulate the uptake and distribution of Zn, which is essential for plant growth and development. Here, we show that Arabidopsis thaliana PCR2 is essential for Zn redistribution and Zn detoxification. The pcr2 loss-of-function mutant was compromised in growth, both in Zn-excessive and -deficient conditions. The roots of pcr2 accumulated more Zn than did control plants, whereas the roots of plants overexpressing PCR2 contained less Zn, indicating that PCR2 removes Zn from the roots. Consistent with a role for PCR2 as a Zn-efflux transporter, PCR2 reduced the intracellular concentration of Zn when expressed in yeast cells. PCR2 is located mainly in epidermal cells and in the xylem of young roots, while it is expressed in epidermal cells in fully developed roots. Zn accumulated in the epidermis of the roots of pcr2 grown under Zn-limiting conditions, whereas it was found in the stele of wild-type roots. The transport pathway mediated by PCR2 does not seem to overlap with that mediated by the described Zn translocators (HMA2 and HMA4) since the growth of pcr2 hma4 double and pcr2 hma2 hma4 triple loss-of-function mutants was more severely inhibited than the individual single knockout mutants, both under conditions of excess or deficient Zn. We propose that PCR2 functions as a Zn transporter essential for maintaining an optimal Zn level in Arabidopsis.


Assuntos
Proteínas de Arabidopsis/fisiologia , Arabidopsis/metabolismo , Zinco/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Transporte Biológico , Reação em Cadeia da Polimerase Via Transcriptase Reversa
10.
Physiol Plant ; 147(4): 432-42, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22938023

RESUMO

Lycopene ε-cyclase (LCY-ε) is involved in the first step of the α-branch synthesis pathway of carotenoids from lycopene in plants. In this study, to enhance carotenoid synthesis via the ß-branch-specific pathway [which yields ß-carotene and abscisic acid (ABA)] in sweet potato, the expression of IbLCY-ε was downregulated by RNAi (RNA interference) technology. The RNAi-IbLCY-ε vector was constructed using a partial cDNA of sweet potato LCY-ε isolated from the storage root and introduced into cultured sweet potato cells by Agrobacterium-mediated transformation. Both semi-quantitative Reverse transcription polymerase chain reaction (RT-PCR) of carotenoid biosynthesis genes and high-performance liquid chromatography (HPLC) analysis of the metabolites in transgenic calli, in which the LCY- εgene was silenced, showed the activation of ß-branch carotenoids and its related genes. In the transgenic calli, the ß-carotene content was approximately 21-fold higher than in control calli, whereas the lutein content of the transgenic calli was reduced to levels undetectable by HPLC. Similarly, expression of the RNAi-IbLCY-ε transgene resulted in a twofold increase in ABA content compared to control calli. The transgenic calli showed significant tolerance of 200 mM NaCl. Furthermore, both the ß-branch carotenoids content and the expression levels of various branch-specific genes were higher under salt stress than in control calli. These results suggest that, in sweet potato, downregulation of the ε-cyclization of lycopene increases carotenoid synthesis via the ß-branch-specific pathway and may positively regulate cellular defenses against salt-mediated oxidative stress.


Assuntos
Carotenoides/biossíntese , Regulação da Expressão Gênica de Plantas , Liases Intramoleculares/genética , Ipomoea batatas/genética , Ácido Abscísico/genética , Ácido Abscísico/metabolismo , Antioxidantes/metabolismo , Carotenoides/genética , Carotenoides/metabolismo , Regulação para Baixo , Liases Intramoleculares/metabolismo , Ipomoea batatas/metabolismo , Redes e Vias Metabólicas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Interferência de RNA , Tolerância ao Sal/genética
11.
Physiol Plant ; 148(2): 189-99, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23039825

RESUMO

R2R3-type MYB transcription factors (TFs) play important roles in transcriptional regulation of anthocyanins. The R2R3-type IbMYB1 is known to be a key regulator of anthocyanin biosynthesis in the storage roots of sweetpotato. We previously showed that transient expression of IbMYB1a led to anthocyanin pigmentation in tobacco leaves. In this article, we generated transgenic Arabidopsis plants expressing the IbMYB1a gene under the control of CaMV 35S promoter, and the sweetpotato SPO and SWPA2 promoters. Overexpression of IbMYBa in transgenic Arabidopsis produced strong anthocyanin pigmentation in seedlings and generated a deep purple color in leaves, stems and seeds. Reverse transcription-polymerase chain reaction analysis showed that IbMYB1a expression induced upregulation of several structural genes in the anthocyanin biosynthetic pathway, including 4CL, CHI, F3'H, DFR, AGT, AAT and GST. Furthermore, overexpression of IbMYB1a led to enhanced expression of the AtTT8 (bHLH) and PAP1/AtMYB75 genes. high-performance liquid chromatography analysis revealed that IbMYB1a expression led to the production of cyanidin as a major core molecule of anthocyanidins in Arabidopsis, as occurs in the purple leaves of sweetpotato (cv. Sinzami). This result shows that the IbMYB1a TF is sufficient to induce anthocyanin accumulation in seedlings, leaves, stems and seeds of Arabidopsis plants.


Assuntos
Antocianinas/metabolismo , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Ipomoea batatas/genética , Fatores de Transcrição/genética , Antocianinas/análise , Arabidopsis/metabolismo , Expressão Gênica , Especificidade de Órgãos , Proteínas Associadas a Pancreatite , Fenótipo , Pigmentação , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Caules de Planta/genética , Caules de Planta/metabolismo , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas/genética , Plântula/genética , Plântula/metabolismo , Sementes/genética , Sementes/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Gênica
12.
RSC Adv ; 13(44): 31027-31035, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37901852

RESUMO

Organic-inorganic hybrid compounds have recently gained significant attention in recent years due to their diverse applications. Herein, [NH3(CH2)6NH3]ZnCl4 crystals were grown, and their triclinic structure, phase transition temperature (TC = 408 K), and high thermal stability (Td = 584 K) was determined using X-ray diffraction (XRD), differential scanning calorimetry, and thermogravimetry measurements. By analyzing the chemical in response to temperature changes, we observed that the coordination geometry around 1H and 13C were highly symmetric below TC, whereas their symmetry was lowered above TC. The change of N-H⋯Cl hydrogen bond from XRD results and the change of 14N NMR chemical shifts was due to the changes to the coordination geometry of Cl- around Zn2+ in the ZnCl4 anion. The activation energy of 1H was three times greater than that of 13C, and this result indicates that the energy transfer of 13C was easier than those of 1H. We compared the results for [NH3(CH2)nNH3]ZnCl4 (n = 6) studied here with those for n = 2, 3, 4, and 5 obtained from previous studies. The characteristics of the length of CH2 in the methylene chain are expected to be used for potential applications in the near future.

13.
ACS Omega ; 8(37): 34180-34187, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37744861

RESUMO

A comprehensive understanding of the physicochemical properties of organic-inorganic hybrids is essential for their solid-state lighting applications. Therefore, a single crystal of [NH2(CH3)2]2CdBr4 was grown; the crystal structure was monoclinic, and the phase transition temperatures for the four phases IV, III, II, and I were 383 K (TC1), 417 K (TC2), and 427 K (TC3). Furthermore, the chemical shifts caused by the local field around 1H, 13C, 14N, and 113Cd changed continuously with temperature, especially near TC1, indicating that the local environment changes with temperature. Owing to the large change in 113Cd chemical shifts, the coordination geometry of Br around Cd in the CdBr4 tetrahedra changes near TC1. Therefore, it is proposed that Br plays a significant role in the N-H···Br hydrogen bond. Finally, the spin-lattice relaxation time T1ρ, representing the energy transfer around the 1H and 13C atoms of the cation, changed significantly with temperature. The activation energies obtained from the T1ρ results were two times larger at high temperatures than at low temperatures. This study provides an understanding of the fundamental properties of organic-inorganic hybrid compounds to broaden their applications.

14.
Mol Biol Rep ; 39(3): 2059-67, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21643753

RESUMO

The expression profiles of three Brassica rapa metallothionein genes (BrMT 1-3) were determined in 7-day-old seedlings exposed to various exogenous factors including plant hormones, heavy metals and abiotic stresses. BrMT1, BrMT2, and BrMT3 were representatives of MT gene type 1, type 2, and type 3, respectively, according to their cysteine alignment. BrMT2 showed a relatively higher basal expression level compared to BrMT1 and BrMT3 under normal conditions. The BrMT1 transcript was markedly increased by various factors including ethephon, polyethylene glycol and hydrogen peroxide, with no down-regulation evident. On the contrary, BrMT2 expression was down-regulated by abscisic acid, salicylic acid, and methyl jasmonate. Heavy metals did not increase BrMT2 expression. BrMT3 expression was only marginally and non-significantly up- and down-regulated by the stress conditions tested. Promoter regions of BrMT1 and BrMT2 display different cis-acting elements supporting the different responses of both genes against various stresses. The results demonstrate the differential regulation of BrMT1-3 by various plant exogenous factors, and indicate the utility of the BrMT1 promoter as a multiple stress inducible promoter.


Assuntos
Brassica rapa/genética , Regulação da Expressão Gênica de Plantas/genética , Metalotioneína/genética , Plântula/genética , Ácido Abscísico , Acetatos , Brassica rapa/metabolismo , Ciclopentanos , Primers do DNA/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Peróxido de Hidrogênio , Metais Pesados/toxicidade , Compostos Organofosforados , Oxilipinas , Reguladores de Crescimento de Plantas/farmacologia , Polietilenoglicóis , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ácido Salicílico , Plântula/metabolismo
15.
Front Plant Sci ; 13: 985559, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36204076

RESUMO

In rice, low-temperature germinability (LTG) is essential for stable stand establishment using the direct seeding method in temperate and high-altitude areas. Previously, we reported that the quantitative trait locus qLTG1 is associated with LTG. qLTG1 is also associated with tolerance to several abiotic stresses, such as salt and osmotic conditions. In this study, map-based cloning and sequence analysis indicated that qLTG1 is allelic to DWARF2 (OsD2), which encodes cytochrome P450 D2 (LOC_Os01g10040) involved in brassinosteroid (BR) biosynthesis. Sequence comparison of the two parental lines, Hwaseong and Oryza rufipogon (IRGC 105491), revealed five single nucleotide polymorphisms (SNPs) in the coding region. Three of these SNPs led to missense mutations in OsD2, whereas the other two SNPs were synonymous. We evaluated two T-DNA insertion mutants, viz., overexpression (OsD2-OE) and knockdown (OsD2-KD) mutants of OsD2, with the Dongjin genetic background. OsD2-KD plants showed a decrease in LTG and grain size. In contrast, OsD2-OE plants showed an increase in grain size and LTG. We also examined the expression levels of several BR signaling and biosynthetic genes using the T-DNA insertion mutants. Gene expression analysis and BR application experiments demonstrated that BR enhanced the seed germination rate under low-temperature conditions. These results suggest that OsD2 is associated with the regulation of LTG and improving grain size. Thus, OsD2 may be a suitable target for rice breeding programs to improve rice yield and LTG.

16.
Oncogene ; 41(2): 280-292, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34743207

RESUMO

We previously found the SLC3A2-NRG1 (S-N) fusion gene in a lung adenocarcinoma specimen without known driver mutations and validated this in 59 invasive mucinous adenocarcinoma (IMA) samples. Interestingly, KRAS mutation coexisted (62.5%) in 10 out of 16 NRG1 fusions. In this study, we examined the role of mutant KRAS in regulating the S-N fusion protein in KRAS mutant (H358) and wild-type (Calu-3) cells. KRAS mutation-mediated increase in MEK1/2 and ERK1/2 activity enhanced disintegrin and metalloproteinase (ADAM)17 activity, which increased the shedding of NRG1 from the S-N fusion protein. The cleavage of NRG1 also increased the phosphorylation of ERBB2-ERBB3 heterocomplex receptors and their downstream signalling pathways, including PI3K/Akt/mTOR, even under activated KRAS mutation signalling. The concurrence of S-N fusion and KRAS mutation synergistically increased cell proliferation, colony formation, tumour growth, and the cells' resistance to EGFR kinase inhibitors more than KRAS mutation alone. Targeted inhibition of MEK1/2, and ADAM17 significantly induced apoptosis singly and when combined with each mutation singly or with chemotherapy in both the concurrent KRAS mutant and S-N fusion xenograft and lung orthotopic models. Taken together, this is the first study to report that KRAS mutation increased NRG1 cleavage from the S-N fusion protein through ADAM17, thereby enhancing the Ras/Raf/MEK/ERK and ERBB/PI3K/Akt/mTOR pathways. Moreover, the coexistence of KRAS mutant and S-N fusion in lung tumours renders them vulnerable to MEK1/2 and/or ADAM17 inhibitors, at least in part, due to their dependency on the strong positive loop between KRAS mutation and S-N fusion.


Assuntos
Proteína ADAM17/metabolismo , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/genética , Neuregulina-1/genética , Oncogenes/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Animais , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Humanos , Neoplasias Pulmonares/patologia , Neuregulina-1/metabolismo , Transfecção
17.
ACS Omega ; 6(41): 27568-27577, 2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34693178

RESUMO

Hybrid perovskites have potential applications in several electrochemical devices such as supercapacitors, batteries, and fuel cells. Here, the thermal stabilities as a function of the length n of the CH2 groups in [NH3(CH2) n NH3]CdCl4 (n = 2, 3, and 4) crystals were considered by TGA and DTA. The structural characteristics and molecular dynamics were studied by MAS and static NMR experiments. A comparison of spin-lattice relaxation times indicated that the organic cation containing 1H and 13C was significantly more flexible than the inorganic anion containing 113Cd. The flexibility of 1H increased with an increase in the length of CH2 in the carbon chain, resulting in a decrease in the activation energy (E a) of 1H. The E a of 13C at n = 3 and 4 was more flexible at high temperatures than at low temperatures. In contrast, the E a of 13C at n = 2 was more flexible at low temperatures. These results provide insight into the thermal stability and molecular dynamics of these crystals as a function of the length n of CH2 groups in the carbon chain and are expected to facilitate applications.

18.
Sci Rep ; 11(1): 8408, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33863967

RESUMO

The physical properties of the organic-inorganic hybrid crystals having the formula [NH3(CH2)3NH3]ZnX4 (X = Cl, Br) were investigated. The phase transition temperatures (TC; 268K for Cl and 272K for Br) of the two crystals bearing different halogen atoms in their skeletons were determined through differential scanning calorimetry. The thermodynamic properties of the two crystals were investigated through thermogravimetric analysis. The structural dynamics, particularly the role of the [NH3(CH2)3NH3] cation, were probed through 1H and 13C magic-angle spinning nuclear magnetic resonance spectroscopy as a function of temperature. The 1H and 13C NMR chemical shifts did not show any changes near TC. In addition, the 1H spin-lattice relaxation time (T1ρ) varied with temperature, whereas the 13C T1ρ values remained nearly constant at different temperatures. The T1ρ values of the atoms in [NH3(CH2)3NH3]ZnCl4 were higher than those in [NH3(CH2)3NH3]ZnBr4. The observed differences in the structural dynamics obtained from the chemical shifts and T1ρ values of the two compounds can be attributed to the differences in the bond lengths and halogen atoms. These findings can provide important insights or potential applications of these crystals.

19.
PLoS One ; 16(6): e0252899, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34086824

RESUMO

Brassica rapa is an important leafy vegetable that can potentially accumulate high concentrations of cadmium (Cd), posing a risk to human health. The aim of the present study was to identify cadmium detoxifying molecular mechanisms in B. rapa using a functional cloning strategy. A cDNA library constructed from roots of B. rapa plants treated with Cd was transformed into the Cd sensitive yeast mutant strain DTY167 that lacks the yeast cadmium factor (YCF1), and resistant yeast clones were selected on Cd containing media. Two hundred genes potentially conferring cadmium resistance were rescued from the surviving yeast clones and sequenced. Sequencing analysis revealed that genes encoding for metallothionein (MT)1, MT2a, MT2b and MT3, and phytochelatin synthase (PCS)1 and PCS2 accounted for 35.5%, 28.5%, 4%, 11.3%, 18.7% and 2%, respectively of the genes identified. MTs and PCSs expressing DTY167 cells showed resistance to Cd as well as to Zn. PCS1 expressing yeast cells were also more resistant to Pb compared to those expressing MTs or PCS2. RT-PCR results showed that Cd treatment strongly induced the expression levels of MTs in the root and shoot. Furthermore, the different MTs and PCSs exhibited tissue specific expression. The results indicate that MTs and PCS genes potentially play a central role in detoxifying Cd and other toxic metals in B. rapa.


Assuntos
Aminoaciltransferases/metabolismo , Brassica rapa/metabolismo , Cádmio/toxicidade , Tolerância a Medicamentos/genética , Metalotioneína/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Aminoaciltransferases/genética , Brassica rapa/efeitos dos fármacos , Brassica rapa/genética , Brassica rapa/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Metalotioneína/genética , Fitoquelatinas/metabolismo , Proteínas de Plantas/genética , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento
20.
Appl Sci (Basel) ; 11(18)2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36003951

RESUMO

Conventional root canal treatment may result in loss of tooth vitality, which can lead to unfavorable treatment outcomes. Notably, a ceased tooth development of immature permanent teeth with open apices, regeneration of periodontal ligaments (PDL), and pulp is highly expected healing process. For regeneration, the scaffold is one of the critical components that carry biological benefits. Therefore, this study evaluated a decellularized human tooth as a scaffold for the PDL and pulp tissue regeneration. A tooth scaffold was fabricated using an effective decellularization method as reported in previous studies. PDL stem cells (PDLSCs) and dental pulp stem cells (DPSCs) obtained from human permanent teeth were inoculated onto decellularized scaffolds, then cultured to transplant into immunosuppressed mouse. After 9 weeks, PDLSCs and DPSCs that were inoculated onto decellularized tooth scaffolds and cultured in an in vivo demonstrated successful differentiation. In PDLSCs, a regeneration of the cementum/PDL complex could be expected. In DPSCs, the expression of genes related to revascularization and the hard tissue regeneration showed the possibility of pulp regeneration. This study suggested that the potential possible application of decellularized human tooth could be a scaffold in regeneration PDL and pulp tissue along with PDLSCs and DPSCs, respectively, as a novel treatment method.

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