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1.
BMC Plant Biol ; 24(1): 796, 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39174961

RESUMO

BACKGROUND: Abiotic stress seriously affects the growth and yield of crops. It is necessary to search and utilize novel abiotic stress resistant genes for 2.0 breeding programme in quinoa. In this study, the impact of drought stress on glucose metabolism were investigated through transcriptomic and metabolomic analyses in quinoa seeds. Candidate drought tolerance genes on glucose metabolism pathway were verified by qRT-PCR combined with yeast expression system. RESULTS: From 70 quinoa germplasms, drought tolerant material M059 and drought sensitive material M024 were selected by comprehensive evaluation of drought resistance. 7042 differentially expressed genes (DEGs) were indentified through transcriptomic analyses. Gene Ontology (GO) analysis revealed that these DEGs were closely related to carbohydrate metabolic process, phosphorus-containing groups, and intracellular membrane-bounded organelles. The Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis detected that DEGs were related to pathways involving carbohydrate metabolisms, glycolysis and gluconeogenesis. Twelve key differentially accumulated metabolites (DAMs), (D-galactose, UDP-glucose, succinate, inositol, D-galactose, D-fructose-6-phosphate, D-glucose-6-phosphate, D-glucose-1-phosphate, dihydroxyacetone phosphate, ribulose-5-phosphate, citric acid and L-malate), and ten key candidate DEGs (CqAGAL2, CqINV, CqFrK7, CqCELB, Cqbg1x, CqFBP, CqALDO, CqPGM, CqIDH3, and CqSDH) involved in drought response were identified. CqSDH, CqAGAL2, and Cqß-GAL13 were candidate genes that have been validated in both transcriptomics and yeast expression screen system. CONCLUSION: These findings provide a foundation for elucidating the molecular regulatory mechanisms governing glucose metabolism in quinoa seeds under drought stress, providing insights for future research exploring responses to drought stress in quinoa.


Assuntos
Chenopodium quinoa , Secas , Glucose , Sementes , Chenopodium quinoa/genética , Chenopodium quinoa/metabolismo , Chenopodium quinoa/fisiologia , Glucose/metabolismo , Sementes/metabolismo , Sementes/genética , Estresse Fisiológico/genética , Regulação da Expressão Gênica de Plantas , Transcriptoma , Perfilação da Expressão Gênica , Metabolismo dos Carboidratos/genética
2.
Int J Mol Sci ; 25(6)2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38542405

RESUMO

14-3-3 proteins are widely distributed in eukaryotic cells and play an important role in plant growth, development, and stress tolerance. This study revealed nine 14-3-3 genes from the genome of Nitraria sibirica Pall., a halophyte with strong salt tolerance. The physicochemical properties, multiple sequence alignment, gene structure and motif analysis, and chromosomal distributions were analyzed, and phylogenetic analysis, cis-regulatory elements analysis, and gene transcription and expression analysis of Ns14-3-3s were conducted. The results revealed that the Ns14-3-3 gene family consists of nine members, which are divided into two groups: ε (four members) and non-ε (five members). These members are acidic hydrophilic proteins. The genes are distributed randomly on chromosomes, and the number of introns varies widely among the two groups. However, all genes have similar conserved domains and three-dimensional protein structures. The main differences are found at the N-terminus and C-terminus. The promoter region of Ns14-3-3s contains multiple cis-acting elements related to light, plant hormones, and abiotic stress responses. Transcriptional profiling and gene expression pattern analysis revealed that Ns14-3-3s were expressed in all tissues, although with varying patterns. Under salt stress conditions, Ns14-3-3 1a, Ns14-3-3 1b, Ns14-3-3 5a, and Ns14-3-3 7a showed significant changes in gene expression. Ns14-3-3 1a expression decreased in all tissues, Ns14-3-3 7a expression decreased by 60% to 71% in roots, and Ns14-3-3 1b expression increased by 209% to 251% in stems. The most significant change was observed in Ns14-3-3 5a, with its expression in stems increasing by 213% to 681%. The yeast two-hybrid experiments demonstrated that Ns14-3-3 5a interacts with NsVP1 (vacuolar H+-pyrophosphatase). This result indicates that Ns14-3-3 5a may respond to salt stress by promoting ionic vacuole compartmentalization in stems and leaves through interactions with NsVP1. In addition, N. sibirica has a high number of stems, allowing it to compartmentalize more ions through its stem and leaf. This may be a contributing factor to its superior salt tolerance compared to other plants.


Assuntos
Magnoliopsida , Estresse Salino , Filogenia , Estresse Salino/genética , Tolerância ao Sal/genética , Íntrons/genética , Proteínas 14-3-3/genética , Pirofosfatase Inorgânica , Proteínas de Plantas/genética , Regulação da Expressão Gênica de Plantas , Estresse Fisiológico/genética
3.
BMC Plant Biol ; 23(1): 65, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36721098

RESUMO

BACKGROUND: The desert shrub Nitraria tangutorum Bobr. is important for its resistance to salt and alkali in Northwest China. It is an ecologically important species in this region and provides edible and medicinal berries. This study showed a mutant of N. tangutorum (named Jincan, JC) that has a strong yellow pericarp vs red in a wild type (represented by NT). RESULTS: In this study, the secondary metabolic and molecular mechanisms responsible for Nitraria fruit coloration were investigated using LC-MS-based widely targeted metabolomics and transcriptomics data. As a result of our study, 122 and 104 flavonoid metabolites were differentially expressed throughout the mature and transition stages between JC and NT, respectively. Furthermore, two cyanidin derivatives (cyanidin 3-O-glucoside and cyanidin-3-O-(2''-O-glucosyl) glucoside) and one pelargonidin derivative (pelargonidin-3-O-glucoside) were identified only in the NT phenotype. The functional genes F3H (flavanone 3-hydroxylase), F3'H (flavonoid 3'-hydroxylase) and UFGT (flavonoid 3-O-glucosyltransferase) and the transcription factors MYB, bHLH, NAC and bZIP were significantly downregulated in JC. Meanwhile, the activity of UFGT was extremely low in both periods of JC, with a five-fold higher enzymatic activity of UFGT in RT than in YT. In summary, due to the lack of catalysis of UGFT, yellow fruit of JC could not accumulate sufficient cyanidin and pelargonidin derivatives during fruit ripening. CONCLUSION: Taken together, our data provide insights into the mechanism for the regulation of anthocyanin synthesis and N. tangutorum fruit coloration and provide a theoretical basis to develop new strategies for developing bioactive compounds from N. tangutorum fruits.


Assuntos
Frutas , Metaboloma , Frutas/genética , Metabolômica , Metabolismo Secundário , Flavonoides
4.
BMC Plant Biol ; 22(1): 592, 2022 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-36526980

RESUMO

BACKGROUND: Nitraria sibirica Pall. is a halophytic shrub with strong environmental adaptability that can survive in extremely saline-alkali and drought-impacted environments. Gene expression analysis aids in the exploration of the molecular mechanisms of plant responses to abiotic stresses. RT-qPCR is the most common technique for studying gene expression. Stable reference genes are a prerequisite for obtaining accurate target gene expression results in RT-qPCR analysis. RESULTS: In this study, a total of 10 candidate reference genes were selected from the transcriptome of N. sibirica, and their expression stability in leaves and roots under different treatment conditions (salt, alkali, drought, cold, heat and ABA) was evaluated with the geNorm, NormFinder, BestKeeper, comparative ΔCt and RefFinder programs. The results showed that the expression stability of the candidate reference genes was dependent on the tissue and experimental conditions tested. ACT7 combined with R3H, GAPDH, TUB or His were the most stable reference genes in the salt- or alkali-treated leaves, salt-treated roots and drought-treated roots, respectively; R3H and GAPDH were the most suitable combination for drought-treated leaves, heat-treated root samples and ABA-treated leaves; DIM1 and His maintained stable expression in roots under alkali stress; and TUB combined with R3H was stable in ABA-treated roots. TBCB and GAPDH exhibited stable expression in heat-treated leaves; TBCB, R3H, and ERF3A were stable in cold-treated leaves; and the three most stable reference genes for cold-treated roots were TBCB, ACT11 and DIM1. The reliability of the selected reference genes was further confirmed by evaluating the expression patterns of the NsP5CS gene under the six treatment conditions. CONCLUSION: This study provides a theoretical reference for N. sibirica gene expression standardization and quantification under various abiotic stress conditions and will help to reveal the molecular mechanisms that confer stress tolerance to N. sibirica.


Assuntos
Genes de Plantas , Magnoliopsida , Genes de Plantas/genética , Regulação da Expressão Gênica de Plantas , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase em Tempo Real/métodos , Estresse Fisiológico/genética , Padrões de Referência , Magnoliopsida/genética , Perfilação da Expressão Gênica/métodos , Cloreto de Sódio , Álcalis
5.
Int J Mol Sci ; 23(9)2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35563299

RESUMO

Phospholipase Dα (PLDα), which produces signaling molecules phosphatidic acid (PA), has been shown to play a critical role in plants adapting to salt environments. However, it is unclear whether phospholipase Dδ (PLDδ) can mediate the salt response in higher plants. PePLDδ was isolated from salt-resistant Populus euphratica and transferred to Arabidopsis thaliana to testify the salt tolerance of transgenic plants. The NaCl treatment (130 mM) reduced the root growth and whole-plant fresh weight of wild-type (WT) A. thaliana, vector controls (VC) and PePLDδ-overexpressed lines, although a less pronounced effect was observed in transgenic plants. Under salt treatment, PePLDδ-transgenic Arabidopsis exhibited lower electrolyte leakage, malondialdehyde content and H2O2 levels than WT and VC, resulting from the activated antioxidant enzymes and upregulated transcripts of genes encoding superoxide dismutase, ascorbic acid peroxidase and peroxidase. In addition, PePLDδ-overexpressed plants increased the transcription of genes encoding the plasma membrane Na+/H+ antiporter (AtSOS1) and H+-ATPase (AtAHA2), which enabled transgenic plants to proceed with Na+ extrusion and reduce K+ loss under salinity. The capacity to regulate reactive oxygen species (ROS) and K+/Na+ homeostasis was associated with the abundance of specific PA species in plants overexpressing PePLDδ. PePLDδ-transgenic plants retained a typically higher abundance of PA species, 34:2 (16:0-18:2), 34:3 (16:0-18:3), 36:4 (18:2-18:2), 36:5 (18:2-18:3) and 36:6 (18:3-18:3), under control and saline conditions. It is noteworthy that PA species 34:2 (16:0-18:2), 34:3 (16:0-18:3), 36:4 (18:2-18:2) and 36:5 (18:2-18:3) markedly increased in response to NaCl in transgenic plants. In conclusion, we suppose that PePLDδ-derived PA enhanced the salinity tolerance by regulating ROS and K+/Na+ homeostasis in Arabidopsis.


Assuntos
Arabidopsis , Populus , Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Homeostase , Peróxido de Hidrogênio/metabolismo , Peroxidases/metabolismo , Fosfolipases/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Populus/genética , Populus/metabolismo , ATPases Translocadoras de Prótons/genética , Espécies Reativas de Oxigênio/metabolismo , Tolerância ao Sal/genética , Sódio/metabolismo , Cloreto de Sódio/metabolismo
6.
Int J Mol Sci ; 22(18)2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34576057

RESUMO

Stomatal regulation is crucial to reduce water consumption under drought conditions. Extracellular ATP (eATP) serves as a signaling agent in stomatal regulation; however, it is less known whether the eATP mediation of stomatal aperture is linked to apyrases (APYs), the principal enzymes that control the concentration of eATP. To clarify the role of APYs in stomatal control, PeAPY1 and PeAPY2 were isolated from Populus euphratica and transferred into Arabidopsis. Compared with the wild-type Arabidopsis and loss-of-function mutants (Atapy1 and Atapy2), PeAPY1- and PeAPY2-transgenic plants decreased stomatal aperture under mannitol treatment (200 mM, 2 h) and reduced water loss during air exposure (90 min). The role of apyrase in stomatal regulation resulted from its control in eATP-regulated stomatal movements and increased stomatal sensitivity to ABA. The bi-phasic dose-responses to applied nucleotides, i.e., the low ATP (0.3-1.0 mM)-promoted opening and high ATP (>2.0 mM)-promoted closure, were both restricted by P. euphratica apyrases. It is noteworthy that eATP at a low concentration (0.3 mM) counteracted ABA action in the regulation of stomatal aperture, while overexpression of PeAPY1 or PeAPY2 effectively diminished eATP promotion in opening, and consequently enhanced ABA action in closure. We postulate a speculative model of apyrase signaling in eATP- and ABA-regulated stomatal movements under drought.


Assuntos
Apirase/genética , Arabidopsis/genética , Plantas Geneticamente Modificadas/genética , Populus/enzimologia , Arabidopsis/crescimento & desenvolvimento , Secas , Regulação da Expressão Gênica de Plantas/genética , Estômatos de Plantas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Populus/genética , Estresse Fisiológico/genética
7.
Int J Mol Sci ; 22(21)2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34769083

RESUMO

Cadmium (Cd2+) pollution occurring in salt-affected soils has become an increasing environmental concern in the world. Fast-growing poplars have been widely utilized for phytoremediation of soil contaminating heavy metals (HMs). However, the woody Cd2+-hyperaccumulator, Populus × canescens, is relatively salt-sensitive and therefore cannot be directly used to remediate HMs from salt-affected soils. The aim of the present study was to testify whether colonization of P. × canescens with ectomycorrhizal (EM) fungi, a strategy known to enhance salt tolerance, provides an opportunity for affordable remediation of Cd2+-polluted saline soils. Ectomycorrhization with Paxillus involutus strains facilitated Cd2+ enrichment in P. × canescens upon CdCl2 exposures (50 µM, 30 min to 24 h). The fungus-stimulated Cd2+ in roots was significantly restricted by inhibitors of plasmalemma H+-ATPases and Ca2+-permeable channels (CaPCs), but stimulated by an activator of plasmalemma H+-ATPases. NaCl (100 mM) lowered the transient and steady-state Cd2+ influx in roots and fungal mycelia. Noteworthy, P. involutus colonization partly reverted the salt suppression of Cd2+ uptake in poplar roots. EM fungus colonization upregulated transcription of plasmalemma H+-ATPases (PcHA4, 8, 11) and annexins (PcANN1, 2, 4), which might mediate Cd2+ conductance through CaPCs. EM roots retained relatively highly expressed PcHAs and PcANNs, thus facilitating Cd2+ enrichment under co-occurring stress of cadmium and salinity. We conclude that ectomycorrhization of woody hyperaccumulator species such as poplar could improve phytoremediation of Cd2+ in salt-affected areas.


Assuntos
Basidiomycota/fisiologia , Cádmio/metabolismo , Micorrizas/fisiologia , Populus/fisiologia , Sais/metabolismo , Biodegradação Ambiental , Salinidade , Cloreto de Sódio/metabolismo , Poluentes do Solo/metabolismo , Madeira/fisiologia
8.
Biochem Biophys Res Commun ; 526(4): 1100-1105, 2020 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-32307082

RESUMO

There is a growing body of evidence that abscisic acid (ABA) and the phytochrome-interacting factor (PIF) family of transcription factors interact in light signaling, the regulation of plant growth development, and adaptation to environmental stimuli. In this study, we investigate the role that PIFs play in the regulation of ABA signaling in Arabidopsis thaliana seedlings grown under long-day conditions. We showed that PIFs positively regulate ABA signaling in post-germination seedling growth. We analyzed the DNA-binding sites for PIF3 and PIF5 by DNA-affinity purification sequencing (DAP-seq) genome-wide. The DAP-seq data showed that G-box motif is the direct binding site of PIF3 and PIF5, and a number of ABA responsive genes are potential targets of PIFs, including PYL3, PYL6, PYL12, SnRK2.2, CPK4, CPK6, ABI5, ABF3, and KIN1. Our results provide a basis for understanding the mechanism for PIFs in regulating ABA signal transduction.


Assuntos
Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Fitocromo/metabolismo , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Transdução de Sinais , Ácido Abscísico/farmacologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Sequência de Bases , Sítios de Ligação , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genoma de Planta , Mutação com Perda de Função/genética , Motivos de Nucleotídeos/genética , Plântula/efeitos dos fármacos
9.
J Exp Bot ; 71(4): 1527-1539, 2020 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-31680166

RESUMO

Plasma membrane proton pumps play a crucial role in maintaining ionic homeostasis in salt-resistant Populus euphratica under saline conditions. High levels of NaCl (200 mM) induced PeHA1 expression in P. euphratica roots and leaves. We isolated a 2022 bp promoter fragment upstream of the translational start of PeHA1 from P. euphratica. The promoter-reporter construct PeHA1-pro::GUS was transferred to tobacco plants, demonstrating that ß-glucuronidase activities increased in root, leaf, and stem tissues under salt stress. DNA affinity purification sequencing revealed that PeWRKY1 protein targeted the PeHA1 gene. We assessed the salt-induced transcriptional response of PeWRKY1 and its interaction with PeHA1 in P. euphratica. PeWRKY1 binding to the PeHA1 W-box in the promoter region was verified by a yeast one-hybrid assay, EMSA, luciferase reporter assay, and virus-induced gene silencing. Transgenic tobacco plants overexpressing PeWRKY1 had improved expression of NtHA4, which has a cis-acting W-box in the regulatory region, and improved H+ pumping activity in both in vivo and in vitro assays. We conclude that salt stress up-regulated PeHA1 transcription due to the binding of PeWRKY1 to the W-box in the promoter region of PeHA1. Thus, we conclude that enhanced H+ pumping activity enabled salt-stressed plants to retain Na+ homeostasis.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Populus , Regiões Promotoras Genéticas , ATPases Translocadoras de Prótons/genética , Tolerância ao Sal , Fatores de Transcrição/metabolismo , Proteínas de Ligação a DNA/genética , Expressão Gênica , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Populus/genética , Populus/metabolismo , Tolerância ao Sal/genética , Fatores de Transcrição/genética
10.
BMC Neurol ; 20(1): 97, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32183730

RESUMO

BACKGROUND: In adults, the anastomosis between carotid and vertebrobasilar arteries is usually the posterior communicating artery, sometimes the primitive trigeminal artery. In this case, the basilar artery fed the internal carotid artery through the pontine-to-tentorial artery anastomosis after severe stenosis from traumatic carotid dissection. CASE PRESENTATION: A 32-year-old female was diagnosed with ischemic stroke caused by traumatic carotid artery dissection. Aspirin (100 mg/day) and clopidogrel (75 mg/day) were prescribed. Digital subtraction angiography performed 6 days after stroke onset showed a dissection in the cervical segment of left internal carotid artery with severe local stenosis, and a collateral pathway from BA to the cavernous segment of internal carotid artery through the lateral pontine and tentorial artery. Without interventional therapy, clinical symptoms improved significantly within 10 days after onset. At 3-month follow-up, left common carotid artery angiography showed the stenosis had been significantly improved with a residual aneurysm. There was no collateral pathway between carotid-vertebrobasilar arteries, and a residual small artery originated from the posterior vertical segment of cavernous internal carotid artery. The small artery was clearly visualized by 3-dimensional rotational angiography and identified the tentorial artery. CONCLUSION: To the author's knowledge, this is the first report of a collateral pathway between carotid vertebrobasilar arteries through the pontine-to-tentorial artery anastomosis. Meanwhile, tentorial artery origination directly from the cavernous segment of internal carotid artery is rare and easily mistaken for persistent primitive trigeminal artery. 3-dimensional rotational angiography can provide sensitive and accurate diagnostic assessment of the small artery, and may be a useful tool for screening of abnormal small arteries.


Assuntos
Angiografia Digital , Artéria Basilar/diagnóstico por imagem , Artéria Carótida Interna/diagnóstico por imagem , Adulto , Dissecção Aórtica/diagnóstico por imagem , Doenças das Artérias Carótidas/diagnóstico por imagem , Feminino , Humanos , Acidente Vascular Cerebral/etiologia
11.
Int J Mol Sci ; 21(22)2020 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-33213111

RESUMO

This work aimed at investigating the interactive effects of salt-signaling molecules, i.e., ethylene, extracellular ATP (eATP), H2O2, and cytosolic Ca2+ ([Ca2+]cyt), on the regulation of K+/Na+ homeostasis in Arabidopsisthaliana. The presence of eATP shortened Col-0 hypocotyl length under no-salt conditions. Moreover, eATP decreased relative electrolyte leakage and lengthened root length significantly in salt-treated Col-0 plants but had no obvious effects on the ethylene-insensitive mutants etr1-1 and ein3-1eil1-1. Steady-state ionic flux kinetics showed that exogenous 1-aminocyclopropane-1-carboxylic acid (ACC, an ethylene precursor) and eATP-Na2 (an eATP donor) significantly increased Na+ extrusion and suppressed K+ loss during short-term NaCl treatment. Moreover, ACC remarkably raised the fluorescence intensity of salt-elicited H2O2 and cytosolic Ca2+. Our qPCR data revealed that during 12 h of NaCl stress, application of ACC increased the expression of AtSOS1 and AtAHA1, which encode the plasma membrane (PM) Na+/H+ antiporters (SOS1) and H+-ATPase (H+ pumps), respectively. In addition, eATP markedly increased the transcription of AtEIN3, AtEIL1, and AtETR1, and ACC treatment of Col-0 roots under NaCl stress conditions caused upregulation of AtRbohF and AtSOS2/3, which directly contribute to the H2O2 and Ca2+ signaling pathways, respectively. Briefly, ethylene was triggered by eATP, a novel upstream signaling component, which then activated and strengthened the H2O2 and Ca2+ signaling pathways to maintain K+/Na+ homeostasis under salinity.


Assuntos
Trifosfato de Adenosina/metabolismo , Arabidopsis/metabolismo , Sinalização do Cálcio/efeitos dos fármacos , Cálcio/metabolismo , Etilenos/metabolismo , Homeostase/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Cloreto de Sódio/farmacologia , Proteínas de Arabidopsis/metabolismo
12.
Int J Mol Sci ; 20(4)2019 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-30769802

RESUMO

Sodium chloride (NaCl) induced expression of a jacalin-related mannose-binding lectin (JRL) gene in leaves, roots, and callus cultures of Populus euphratica (salt-resistant poplar). To explore the mechanism of the PeJRL in salinity tolerance, the full length of PeJRL was cloned from P. euphratica and was transformed into Arabidopsis. PeJRL was localized to the cytoplasm in mesophyll cells. Overexpression of PeJRL in Arabidopsis significantly improved the salt tolerance of transgenic plants, in terms of seed germination, root growth, and electrolyte leakage during seedling establishment. Under NaCl stress, transgenic plants retained K⁺ and limited the accumulation of Na⁺. PeJRL-transgenic lines increased Na⁺ extrusion, which was associated with the upward regulation of SOS1, AHA1, and AHA2 genes encoding plasma membrane Na⁺/proton (H⁺) antiporter and H⁺-pumps. The activated H⁺-ATPases in PeJRL-overexpressed plants restricted the channel-mediated loss of K⁺ that was activated by NaCl-induced depolarization. Under salt stress, PeJRL⁻transgenic Arabidopsis maintained reactive oxygen species (ROS) homeostasis by activating the antioxidant enzymes and reducing the production of O2- through downregulation of NADPH oxidases. Of note, the PeJRL-transgenic Arabidopsis repressed abscisic acid (ABA) biosynthesis, thus reducing the ABA-elicited ROS production and the oxidative damage during the period of salt stress. A schematic model was proposed to show the mediation of PeJRL on ABA response, and ionic and ROS homeostasis under NaCl stress.


Assuntos
Arabidopsis/genética , Lectinas de Ligação a Manose/genética , Plantas Geneticamente Modificadas/genética , Estresse Salino/genética , Arabidopsis/efeitos dos fármacos , Arabidopsis/crescimento & desenvolvimento , Citoplasma/efeitos dos fármacos , Citoplasma/genética , Regulação da Expressão Gênica de Plantas , Homeostase , Lectinas de Ligação a Manose/química , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/genética , Lectinas de Plantas/genética , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Populus , Espécies Reativas de Oxigênio/química , Tolerância ao Sal/genética , Cloreto de Sódio/efeitos adversos
13.
Anal Chem ; 90(1): 769-776, 2018 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-29131578

RESUMO

While there is great interest in understanding the fate and transport of nanomaterials in the environment and in biological systems, the detection of nanomaterials in complex matrices by fluorescence methods is complicated by photodegradation, blinking, and the presence of natural organic material and other fluorescent background signals that hamper detection of fluorescent nanomaterials of interest. Optically detected magnetic resonance (ODMR) of nitrogen-vacancy (NV) centers in diamond nanoparticles provides a pathway toward background-free fluorescence measurements, as the application of a resonant microwave field can selectively modulate the intensity from NV centers in nanodiamonds of various diameters in complex materials systems using on-resonance and off-resonance microwave fields. This work represents the first investigation showing how nanoparticle diameter impacts the NV center lifetime and thereby directly impacts the accessible contrast and signal-to-noise ratio when using ODMR to achieve background-free imaging of NV-nanodiamonds in the presence of interfering fluorophores. These results provide new insights that will guide the choice of optimum nanoparticle size and methodology for background-free imaging and sensing applications, while also providing a model system to explore the fate and transport of nanomaterials in the environment.


Assuntos
Nanodiamantes/química , Fluorescência , Espectroscopia de Ressonância Magnética/métodos , Nitrogênio/química , Tamanho da Partícula
14.
Bull Math Biol ; 80(9): 2349-2377, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30073567

RESUMO

Immune interventions consisting in repeated injections are broadly used as they are thought to improve the quantity and the quality of the immune response. However, they also raise several questions that remain unanswered, in particular the number of injections to make or the delay to respect between different injections to achieve this goal. Practical and financial considerations add constraints to these questions, especially in the framework of human studies. We specifically focus here on the use of interleukin-7 (IL-7) injections in HIV-infected patients under antiretroviral treatment, but still unable to restore normal levels of [Formula: see text] T lymphocytes. Clinical trials have already shown that repeated cycles of injections of IL-7 could help maintaining [Formula: see text] T lymphocytes levels over the limit of 500 cells/[Formula: see text]L, by affecting proliferation and survival of [Formula: see text] T cells. We then aim at answering the question: how to maintain a patients level of [Formula: see text] T lymphocytes by using a minimum number of injections (i.e., optimizing the strategy of injections)? Based on mechanistic models that were previously developed for the dynamics of [Formula: see text] T lymphocytes in this context, we model the process by a piecewise deterministic Markov model. We then address the question by using some recently established theory on impulse control problem in order to develop a numerical tool determining the optimal strategy. Results are obtained on a reduced model, as a proof of concept: the method allows to define an optimal strategy for a given patient. This method could be applied to optimize injections schedules in clinical trials.


Assuntos
Infecções por HIV/imunologia , Infecções por HIV/terapia , Interleucina-7/administração & dosagem , Algoritmos , Fármacos Anti-HIV/uso terapêutico , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos/imunologia , Terapia Combinada , Simulação por Computador , Relação Dose-Resposta Imunológica , Esquema de Medicação , Infecções por HIV/tratamento farmacológico , Humanos , Imunoterapia/métodos , Imunoterapia/estatística & dados numéricos , Interleucina-7/uso terapêutico , Cadeias de Markov , Conceitos Matemáticos , Modelos Imunológicos , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/uso terapêutico
15.
Int J Mol Sci ; 19(12)2018 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-30558245

RESUMO

CDPKs (Ca2+-Dependent Protein Kinases) are very important regulators in plant response to abiotic stress. The molecular regulatory mechanism of CDPKs involved in salt stress tolerance remains unclear, although some CDPKs have been identified in salt-stress signaling. Here, we investigated the function of an Arabidopsis CDPK, CPK12, in salt-stress signaling. The CPK12-RNA interference (RNAi) mutant was much more sensitive to salt stress than the wild-type plant GL1 in terms of seedling growth. Under NaCl treatment, Na⁺ levels in the roots of CPK12-RNAi plants increased and were higher than levels in GL1 plants. In addition, the level of salt-elicited H2O2 production was higher in CPK12-RNAi mutants than in wild-type GL1 plants after NaCl treatment. Collectively, our results suggest that CPK12 is required for plant adaptation to salt stress.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas Quinases Dependentes de Cálcio-Calmodulina/genética , Estresse Salino , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Regulação da Expressão Gênica de Plantas , Homeostase , Peróxido de Hidrogênio/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Interferência de RNA , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Sódio/metabolismo
16.
Med Sci Monit ; 23: 4559-4566, 2017 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-28939800

RESUMO

BACKGROUND Acute cerebral infarction is a major clinical subtype of ischemic stroke that has become a leading cause of death and disability worldwide. Aldehyde dehydrogenase 2 (ALDH2) is an important oxidative enzyme in alcohol metabolism. The polymorphism of ALDH2 Glu504Lys polymorphism modifies the activity of this enzyme. However, the potential association between the allelic variation of ALDH2 Glu504Lys with collateral circulation and short-term prognosis of acute cerebral infarction remains unclear. MATERIAL AND METHODS A total of 394 patients with acute cerebral infarction were recruited for ALDH2 genotyping using direct sequencing. Cerebrovascular stenosis and collateral circulation were evaluated by digital subtraction angiography (DSA). Short-term prognosis was assessed in accordance with the modified Ranking Scale (mRS). RESULTS We identified 297 as EAS and 394 as IAS. There were more patients with occluded blood vessel in the opened group and far fewer in the unopened group. ALDH2 polymorphism was significantly different among the primary, secondary, and tertiary opened groups. ALDH2 gene Glu504Lys was significantly associated with short-term prognosis. The genotype GA+AA of ALDH2 gene Glu504Lys locus was an independent risk factor of poor 90-day prognosis. CONCLUSIONS ALDH2 Glu504Lys could be a risk factor for collateral circulation and a negative predictor for short-term prognosis in acute cerebral infarction in Han Chinese. ALDH2 Glu504Lys could be a new therapeutic target for patients with acute cerebral infarction.


Assuntos
Aldeído-Desidrogenase Mitocondrial/genética , Infarto Cerebral/genética , Adulto , Idoso , Aldeído-Desidrogenase Mitocondrial/metabolismo , Alelos , Angiografia Digital/métodos , Povo Asiático/genética , Isquemia Encefálica/genética , Infarto Cerebral/fisiopatologia , Circulação Colateral/genética , Feminino , Frequência do Gene/genética , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Prognóstico , Fatores de Risco , Acidente Vascular Cerebral/genética
17.
Int J Neurosci ; 126(4): 342-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26000808

RESUMO

AIM: Aldehyde dehydrogenase 2 (ALDH2) is a key enzyme that metabolizes acetaldehyde to acetic acid. ALDH2 gene polymorphism modifies its activity and the mutation of ALDH2 gene has been reported to be associated with the protection against ischemic stroke. However, the potential association of allelic variation of ALDH2 with intracranial vascular stenosis and the clinical characteristics of ischemic stroke without coronary artery disease remains unclear. METHODS: In this study, ischemic stroke patients were recruited, National Institutes of Health Stroke Scale scores were analyzed, intracranial arterial stenosis were evaluated by magnetic resonance angiography and gene typing of ALDH2 was determined by polymerase chain reaction and sequencing. RESULTS: We found that the rate of heavy drinking was significantly lower in the ALDH2 mutation group ((*)1/(*)2 and (*)2/(*)2) than in wild-type group ((*)1/(*)1) (18.6% vs. 38.0%, p = 0.01). Plasma homocysteine (Hcy) levels were significantly different in the two groups (15.45 ± 6.39 vs. 13.14 ± 4.45, p = 0.015). The ALDH2 mutation genotype was negatively correlated with severe intracranial vascular stenosis (OR, 0.34; p = 0.002), even after adjustment for high-density lipoprotein cholesterol, Hcy, and heavy drinking (adjusted OR, 0.44; p = 0.03). CONCLUSION: ALDH2(*)2 could be a protective factor and negative predictor for severe intracranial vascular stenosis in ischemic stroke in Han Chinese.


Assuntos
Aldeído Desidrogenase/genética , Povo Asiático/genética , Constrição Patológica/genética , Doenças Arteriais Intracranianas/genética , Acidente Vascular Cerebral/genética , Consumo de Bebidas Alcoólicas/genética , Alelos , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença/genética , Homocisteína/sangue , Humanos , Angiografia por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Mutação , Polimorfismo Genético/genética , Fatores de Proteção , Fatores de Risco , Acidente Vascular Cerebral/sangue
18.
ACS Appl Mater Interfaces ; 16(4): 4896-4903, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38252593

RESUMO

Radio frequency (RF) electronics are vital components of stretchable electronics that require wireless capabilities, ranging from skin-interfaced wearable systems to implantable devices to soft robotics. One of the key challenges in stretchable electronics is achieving near-lossless transmission line technology that can carry high-frequency electrical signals between various RF components. Almost all existing stretchable interconnection strategies only demonstrate direct current or low-frequency electrical properties, limiting their use in high frequencies, especially in the MHz to GHz range. Here, we describe the design and fabrication of a simple stretchable RF transmission line strategy that integrates a quasi-microstrip structure into a stretchable serpentine microscale interconnection. We show the effects of quasi-microstrip structural dimensions on the RF performance based on detailed quantitative analysis and experimentally demonstrate the optimized device capable of carrying RF signals with frequencies of up to 40 GHz with near-lossless characteristics. To show the potential application of our transmission line in stretchable microwave electronics, we designed a single-stage power amplifier system with a gain of 9.8 dB at 9 GHz that fully utilizes our quasi-microstrip transmission line technology.

19.
Clin Transl Oncol ; 25(11): 3203-3216, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37103763

RESUMO

PURPOSE: It is previously reported that aldehyde dehydrogenase 2 family member (ALDH2) shows neuroprotective effects in cerebral ischemia/reperfusion injury. However, whether the protective effects are through mediating the programmed cell death is yet to be fully elucidated. METHODS: In vitro oxygen-glucose deprivation/reoxygenation (OGD/R) model was established in HT22 cells and mouse cortical neurons. Subsequently, ALDH2 expression were assessed by qRT-PCR and western blot. The methylation status was examined by methylation-specific PCR (MS-PCR). Then, ALDH2 expression was promoted and suppressed to explore the role of ALDH2 in OGD/R-treated cells. CCK-8 assay was applied to detect cell viability, and flow cytometry was applied to evaluate cell apoptosis. Western blot was applied to detect the apoptosis-related proteins (Caspase 3, Bcl-2 and Bax), necroptosis-related proteins (RIP3 and MLKL), pyroptosis-related proteins (NLRP3 and GSDMD), ferroptosis-related protein (ACSL4 and GPX4), and autophagy-related proteins (LC3B, and p62). IL-1ß and IL-18 production was evaluated by ELISA assay. Reactive oxygen species production and Fe2+ content were evaluated by the corresponding detection kit. RESULTS: In OGD/R-treated cells, ALDH2 expression was decreased, which was due to the hypermethylation of ALDH2 in the promoter region. ALDH2 overexpression improved cell viability and ALDH2 knockdown suppressed cell viability in OGD/R-treated cells. We also found that ALDH2 overexpression attenuated OGD/R-induced cell apoptosis, pyroptosis, ferroptosis and autophagy, while ALDH2 knockdown facilitated the OGD/R-induced cell apoptosis, pyroptosis, ferroptosis and autophagy. CONCLUSIONS: Collectively, our results implied that ALDH2 attenuated OGD/R-induced cell apoptosis, pyroptosis, ferroptosis and autophagy to promote cell viability in HT22 cells and mouse cortical neurons.


Assuntos
Ferroptose , Piroptose , Camundongos , Animais , Oxigênio , Glucose/metabolismo , Apoptose , Proteínas Reguladoras de Apoptose/metabolismo , Autofagia , Aldeído-Desidrogenase Mitocondrial
20.
Genes (Basel) ; 13(4)2022 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-35456467

RESUMO

BACKGROUND: Nitraria sibirica Pall. is one of the pioneer tree species in saline-alkali areas due to its extreme salt tolerance. However, the lack of information on its genome limits the further exploration of the molecular mechanisms in N. sibirica under salt stress. METHODS: In this study, we used single-molecule real-time (SMRT) technology based on the PacBio Iso-Seq platform to obtain transcriptome data from N. sibirica under salt treatment for the first time, which is helpful for our in-depth analysis of the salt tolerance and molecular characteristics of N. sibirica. RESULTS: Our results suggested that a total of 234,508 circular consensus sequences (CCSs) with a mean read length of 2121 bp were obtained from the 19.26 Gb raw data. Furthermore, based on transcript cluster analysis, 93,713 consensus isoforms were obtained, including 92,116 high-quality isoforms. After removing redundant sequences, 49,240 non-redundant transcripts were obtained from high-quality isoforms. A total of 37,261 SSRs, 1816 LncRNAs and 47,314 CDSs, of which 40,160 carried complete ORFs, were obtained. Based on our transcriptome data, we also analyzed the coding genes of H+-PPase, and the results of both bioinformatics and functional analyses indicated that the gene prediction via full-length transcripts obtained by SMRT technology is reliable and effective. In summary, our research data obtained by SMRT technology provides more reliable and accurate information for the further analysis of the regulatory network and molecular mechanism of N. sibirica under salt stress.


Assuntos
Magnoliopsida , Plantas Tolerantes a Sal , Perfilação da Expressão Gênica/métodos , Magnoliopsida/genética , Isoformas de Proteínas/genética , Tolerância ao Sal , Plantas Tolerantes a Sal/genética
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