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1.
Cell ; 186(21): 4632-4651.e23, 2023 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-37776858

RESUMEN

The dynamics of immunity to infection in infants remain obscure. Here, we used a multi-omics approach to perform a longitudinal analysis of immunity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in infants and young children by analyzing blood samples and weekly nasal swabs collected before, during, and after infection with Omicron and non-Omicron variants. Infection stimulated robust antibody titers that, unlike in adults, showed no sign of decay for up to 300 days. Infants mounted a robust mucosal immune response characterized by inflammatory cytokines, interferon (IFN) α, and T helper (Th) 17 and neutrophil markers (interleukin [IL]-17, IL-8, and CXCL1). The immune response in blood was characterized by upregulation of activation markers on innate cells, no inflammatory cytokines, but several chemokines and IFNα. The latter correlated with viral load and expression of interferon-stimulated genes (ISGs) in myeloid cells measured by single-cell multi-omics. Together, these data provide a snapshot of immunity to infection during the initial weeks and months of life.


Asunto(s)
COVID-19 , SARS-CoV-2 , Adulto , Niño , Lactante , Humanos , Preescolar , SARS-CoV-2/metabolismo , Multiómica , Citocinas/metabolismo , Interferón-alfa , Inmunidad Mucosa
2.
Eur J Immunol ; 53(2): e2250190, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36480793

RESUMEN

T follicular helper (TFH ) cells play an essential role in promoting B cell responses and antibody affinity maturation in germinal centers (GC). A subset of memory CD4+ T cells expressing the chemokine receptor CXCR5 has been described in human blood as phenotypically and clonally related to GC TFH cells. However, the antigen specificity and relationship of these circulating TFH (cTFH ) cells with other memory CD4+ T cells remain poorly defined. Combining antigenic stimulation and T cell receptor (TCR) Vß sequencing, we found T cells specific to tetanus toxoid (TT), influenza vaccine (Flu), or Candida albicans (C.alb) in both cTFH and non-cTFH subsets, although with different frequencies and effector functions. Interestingly, cTFH and non-cTFH cells specific for C.alb or TT had a largely overlapping TCR Vß repertoire while the repertoire of Flu-specific cTFH and non-cTFH cells was distinct. Furthermore, Flu-specific but not C.alb-specific PD-1+ cTFH cells had a "GC TFH -like" phenotype, with overexpression of IL21, CXCL13, and BCL6. Longitudinal analysis of serial blood donations showed that Flu-specific cTFH and non-cTFH cells persisted as stable repertoires for years. Collectively, our study provides insights on the relationship of cTFH with non-cTFH cells and on the heterogeneity and persistence of antigen-specific human cTFH cells.


Asunto(s)
Células T Auxiliares Foliculares , Linfocitos T Colaboradores-Inductores , Humanos , Linfocitos B , Centro Germinal , Receptores de Antígenos de Linfocitos T
3.
BMC Biotechnol ; 24(1): 13, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38459479

RESUMEN

OBJECTIVE: Smoking was a major risk factor for chronic obstructive pulmonary disease (COPD). This study plan to explore the mechanism of Polyphyllin B in lung injury induced by cigarette smoke (CSE) in COPD. METHODS: Network pharmacology and molecular docking were applied to analyze the potential binding targets for Polyphyllin B and COPD. Commercial unfiltered CSE and LPS were used to construct BEAS-2B cell injury in vitro and COPD mouse models in vivo, respectively, which were treated with Polyphyllin B or fecal microbiota transplantation (FMT). CCK8, LDH and calcein-AM were used to detect the cell proliferation, LDH level and labile iron pool. Lung histopathology, Fe3+ deposition and mitochondrial morphology were observed by hematoxylin-eosin, Prussian blue staining and transmission electron microscope, respectively. ELISA was used to measure inflammation and oxidative stress levels in cells and lung tissues. Immunohistochemistry and immunofluorescence were applied to analyze the 4-HNE, LC3 and Ferritin expression. RT-qPCR was used to detect the expression of FcRn, pIgR, STAT3 and NCOA4. Western blot was used to detect the expression of Ferritin, p-STAT3/STAT3, NCOA4, GPX4, TLR2, TLR4 and P65 proteins. 16S rRNA gene sequencing was applied to detect the gut microbiota. RESULTS: Polyphyllin B had a good binding affinity with STAT3 protein, which as a target gene in COPD. Polyphyllin B inhibited CS-induced oxidative stress, inflammation, mitochondrial damage, and ferritinophagy in COPD mice. 16S rRNA sequencing and FMT confirmed that Akkermansia and Escherichia_Shigella might be the potential microbiota for Polyphyllin B and FMT to improve CSE and LPS-induced COPD, which were exhausted by the antibiotics in C + L and C + L + P mice. CSE and LPS induced the decrease of cell viability and the ferritin and LC3 expression, and the increase of NCOA4 and p-STAT3 expression in BEAS-2B cells, which were inhibited by Polyphyllin B. Polyphyllin B promoted ferritin and LC3II/I expression, and inhibited p-STAT3 and NCOA4 expression in CSE + LPS-induced BEAS-2B cells. CONCLUSION: Polyphyllin B improved gut microbiota disorder and inhibited STAT3/NCOA4 pathway to ameliorate lung tissue injury in CSE and LPS-induced mice.


Asunto(s)
Fumar Cigarrillos , Microbioma Gastrointestinal , Lesión Pulmonar , Enfermedad Pulmonar Obstructiva Crónica , Animales , Ratones , Línea Celular , Fumar Cigarrillos/efectos adversos , Ferritinas/metabolismo , Inflamación/patología , Lipopolisacáridos/efectos adversos , Pulmón , Lesión Pulmonar/complicaciones , Lesión Pulmonar/metabolismo , Lesión Pulmonar/patología , Simulación del Acoplamiento Molecular , Enfermedad Pulmonar Obstructiva Crónica/terapia , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , ARN Ribosómico 16S , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/metabolismo
4.
New Phytol ; 242(2): 641-657, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38379453

RESUMEN

Nitrate is the main source of nitrogen (N) available to plants and also is a signal that triggers complex regulation of transcriptional networks to modulate a wide variety of physiological and developmental responses in plants. How plants adapt to soil nitrate fluctuations is a complex process involving a fine-tuned response to nitrate provision and N starvation, the molecular mechanisms of which remain largely uncharted. Here, we report that the wheat transcription factor TaLBD41 interacts with the nitrate-inducible transcription factor TaNAC2 and is repressed by nitrate provision. Electrophoretic mobility shift assay and dual-luciferase system show that the TaLBD41-NAC2 interaction confers homeostatic coordination of nitrate uptake, reduction, and assimilation by competitively binding to TaNRT2.1, TaNR1.2, and TaNADH-GOGAT. Knockdown of TaLBD41 expression enhances N uptake and assimilation, increases spike number, grain yield, and nitrogen harvest index under different N supply conditions. We also identified an elite haplotype of TaLBD41-2B associated with increased spike number and grain yield. Our study uncovers a novel mechanism underlying the interaction between two transcription factors in mediating wheat adaptation to nitrate availability by antagonistically regulating nitrate uptake and assimilation, providing a potential target for designing varieties with efficient N use in wheat (Triticum aestivum).


Asunto(s)
Nitratos , Nitrógeno , Nitratos/metabolismo , Nitrógeno/metabolismo , Transporte Biológico , Grano Comestible/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
5.
Nature ; 560(7720): 595-600, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-30111841

RESUMEN

Enhancing global food security by increasing the productivity of green revolution varieties of cereals risks increasing the collateral environmental damage produced by inorganic nitrogen fertilizers. Improvements in the efficiency of nitrogen use of crops are therefore essential; however, they require an in-depth understanding of the co-regulatory mechanisms that integrate growth, nitrogen assimilation and carbon fixation. Here we show that the balanced opposing activities and physical interactions of the rice GROWTH-REGULATING FACTOR 4 (GRF4) transcription factor and the growth inhibitor DELLA confer homeostatic co-regulation of growth and the metabolism of carbon and nitrogen. GRF4 promotes and integrates nitrogen assimilation, carbon fixation and growth, whereas DELLA inhibits these processes. As a consequence, the accumulation of DELLA that is characteristic of green revolution varieties confers not only yield-enhancing dwarfism, but also reduces the efficiency of nitrogen use. However, the nitrogen-use efficiency of green revolution varieties and grain yield are increased by tipping the GRF4-DELLA balance towards increased GRF4 abundance. Modulation of plant growth and metabolic co-regulation thus enables novel breeding strategies for future sustainable food security and a new green revolution.


Asunto(s)
Agricultura/métodos , Productos Agrícolas/metabolismo , Desarrollo de la Planta , Desarrollo Sostenible , Compuestos de Amonio/metabolismo , Ciclo del Carbono , Nitrógeno/metabolismo , Oryza/crecimiento & desarrollo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Triticum/crecimiento & desarrollo , Triticum/metabolismo , Granos Enteros/crecimiento & desarrollo , Granos Enteros/metabolismo
6.
Health Expect ; 27(1): e13990, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38367247

RESUMEN

BACKGROUND: With the growing challenge of an aging population, addressing the needs of elderly individuals who face living difficulties and lack family support becomes increasingly difficult. Volunteer services are crucial in this context, yet their effectiveness is hindered by unclear service scopes and uncertain volunteer inclinations. AIM: To explore the role and specific preference of volunteers with nursing backgrounds in support of older adults living in the urban community. DESIGN, SETTING AND PARTICIPANTS: A descriptive qualitative study was conducted between September and October 2022. Twenty-three participants (hospital nurses [10], community nurses [4], nursing teachers [4] and nursing students [5]) were selected. Data analysis followed conventional content analysis. RESULTS: Nine major themes were identified based on interview data. Four themes described the service scope of nursing volunteers: (1) environment domain, (2) physiological domain, (3) psychosocial domain and (4) health-related behaviours domain. Another five themes highlighted the service inclination of these volunteers: (1) service frequency, (2) service duration per person/time, (3) service coverage, (4) service place and (5) service object. CONCLUSION: This study clarifies the service focus and scope of necessary support for volunteers, exploring the potential service capabilities of scarce volunteers to the greatest extent. Meanwhile, the results of this study also provide a foundation for stakeholders to fully exploit the synergy. The important findings of this study will help the government and relevant authorities better understand the service attributes of nursing volunteers, allowing them to develop detailed training plans and provide nursing volunteers with targeted support and assistance to meet the health expectations of urban community-living older adults in need. PATIENT OR PUBLIC CONTRIBUTION: Developing research questions, participation and conduct and provision and interpretation of evidence.


Asunto(s)
Voluntarios , Anciano , Humanos , Investigación Cualitativa , Vida Independiente
7.
Opt Express ; 31(7): 11239-11248, 2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-37155764

RESUMEN

Stable propagation of multifilament arrays in transparent bulk media with adjustable separation distances between adjacent child filaments has always been desired for advanced manufacturing. Here, we report on the generation of an ionization-induced volume plasma grating (VPG) by the interaction of two batches of noncollinearly propagating arrays of multiple filaments (AMF). The VPG can externally arrange the propagation of the pulses along regular plasma waveguides via spatial reconstruction of electrical fields, which is compared with the self-formation of randomly distributed multiple filamentation originated from noises. The separation distances of filaments in VPG are controllable by readily changing the crossing angle of the excitation beams. In addition, an innovative method to efficiently fabricate multidimensional grating structures in transparent bulk media through laser modification using VPG was demonstrated.

8.
Plant Biotechnol J ; 20(8): 1606-1621, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35514029

RESUMEN

Genetically enhancing drought tolerance and nutrient use efficacy enables sustainable and stable wheat production in drought-prone areas exposed to water shortages and low soil fertility, due to global warming and declining natural resources. In this study, wheat plants, exhibiting improved drought tolerance and N-use efficacy, were developed by introducing GmTDN1, a gene encoding a DREB-like transcription factor, into two modern winter wheat varieties, cv Shi4185 and Jimai22. Overexpressing GmTDN1 in wheat resulted in significantly improved drought and low-N tolerance under drought and N-deficient conditions in the greenhouse. Field trials conducted at three different locations over a period of 2-3 consecutive years showed that both Shi4185 and Jimai22 GmTDN1 transgenic lines were agronomically superior to wild-type plants, and produced significantly higher yields under both drought and N-deficient conditions. No yield penalties were observed in these transgenic lines under normal well irrigation conditions. Overexpressing GmTDN1 enhanced photosynthetic and osmotic adjustment capacity, antioxidant metabolism, and root mass of wheat plants, compared to those of wild-type plants, by orchestrating the expression of a set of drought stress-related genes as well as the nitrate transporter, NRT2.5. Furthermore, transgenic wheat with overexpressed NRT2.5 can improve drought tolerance and nitrogen (N) absorption, suggesting that improving N absorption in GmTDN1 transgenic wheat may contribute to drought tolerance. These findings may lead to the development of new methodologies with the capacity to simultaneously improve drought tolerance and N-use efficacy in cereal crops to ensure sustainable agriculture and global food security.


Asunto(s)
Sequías , Triticum , Regulación de la Expresión Génica de las Plantas , Fotosíntesis , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Estrés Fisiológico/genética , Factores de Transcripción/genética , Triticum/genética , Triticum/metabolismo
9.
Xenobiotica ; 52(7): 718-728, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36227237

RESUMEN

Curcumin, the main bioactive component of turmeric, has a wild range of beneficial effects on central nervous diseases, including anti-Alzheimer's disease, antioxidant stress, and anti-inflammation. Currently, it has been demonstrated the anti-epileptic potential. However, curcumin has poor water solubility, high sensitivity to light and heat, and low absorption, which results in low bioavailability and greatly limits the clinical application of curcumin, as well as the elusive effects in anti-epileptic treatment.This study aimed to develop a curcumin hydroxypropyl-ß-cyclodextrin inclusion complex (CUR-HP-ß-CD) to improve its bioavailability and facilitate its potential development as an anti-epileptic drug. The CUR-HP-ß-CD was generated by the solvent evaporation method, which has efficient entrapment, high solubility, and facilitated bioavailability and brain distribution.The solubility of the CUR-HP-ß-CD was 63.5, 60.1, and 52.9 times that of the unformulated curcumin in H2O, HCl (pH 1.2), and PBS (pH 6.8), respectively. The bioavailability of CUR-HP-ß-CD is improved 2.8 times and 38.7 folds higher brain concentrations. Moreover, the therapeutic anti-epileptic effects of CUR-HP-ß-CD were much more effective in pentylenetetrazol (PTZ)-induced zebrafish and mouse models.This study showed a simple and reproducible strategy to effectively improve the bioavailability and therapeutic effects of curcumin, which could be potentially used in epilepsy treatment.


Asunto(s)
Curcumina , Epilepsia , Animales , Ratones , 2-Hidroxipropil-beta-Ciclodextrina , Curcumina/farmacología , Pez Cebra , Epilepsia/tratamiento farmacológico
10.
New Phytol ; 225(4): 1667-1680, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31581317

RESUMEN

Seed vigour and early establishment are important factors determining the yield of crops. A wheat nitrate-inducible NAC transcription factor, TaNAC2, plays a critical role in promoting crop growth and nitrogen use efficiency (NUE), and now its role in seed vigour is revealed. A TaNAC2 regulated gene was identified that is a NRT2-type nitrate transporter TaNRT2.5 with a key role in seed vigour. Overexpressing TaNAC2-5A increases grain nitrate concentration and seed vigour by directly binding to the promoter of TaNRT2.5-3B and positively regulating its expression. TaNRT2.5 is expressed in developing grain, particularly the embryo and husk. In Xenopus oocyte assays TaNRT2.5 requires a partner protein TaNAR2.1 to give nitrate transport activity, and the transporter locates to the tonoplast in a tobacco leaf transient expression system. Furthermore, in the root TaNRT2.5 and TaNRT2.1 function in post-anthesis acquisition of soil nitrate. Overexpression of TaNRT2.5-3B increases seed vigour, grain nitrate concentration and yield, whereas RNA interference of TaNRT2.5 has the opposite effects. The TaNAC2-NRT2.5 module has a key role in regulating grain nitrate accumulation and seed vigour. Both genes can potentially be used to improve grain yield and NUE in wheat.


Asunto(s)
Nitratos/metabolismo , Proteínas de Plantas/metabolismo , Semillas/fisiología , Factores de Transcripción/metabolismo , Triticum/metabolismo , Animales , Transporte Biológico , Regulación de la Expresión Génica de las Plantas/fisiología , Oocitos/metabolismo , Proteínas de Plantas/genética , Transporte de Proteínas , Transducción de Señal , Factores de Transcripción/genética , Triticum/genética , Xenopus
11.
Opt Lett ; 45(3): 776-779, 2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-32004309

RESUMEN

In this Letter, we utilize an acoustic-optic frequency shifter in a feedforward manner for automatic interpolation of dual-comb spectroscopy, where frequency tuning can be achieved at 5.45 THz/s with the step size precisely locked to the line spacing (54.5 MHz) of a referenced optical comb without complicated electronics or control programs. Our dual-comb spectrometer involves two near-infrared electro-optic combs at 25 GHz line spacings, nonlinearly converted into the mid-infrared region, revealing fundamental absorption lines of methane gas at 54.5 MHz resolution within a spectral range from 88.04 to 89.04 THz. The method and the system may be useful in many applications, including gas sensing.

12.
Xenobiotica ; 50(3): 354-362, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31132291

RESUMEN

1. More than 30% of epilepsy patients suffer pharmacoresistance. Transport of antileptic drugs by P-glycoprotein (P-gp) and MRP2 plays an important role in drug-resistant epilepsy. Huperzine A (Hup-A) is a natural compound, which might have potential in treating neurological disorders including epilepsy and Alzheimer's disease. In this study, we investigated whether human P-gp and MRP2 transport Hup-A.2. LLC-PK1 and MDCKII cells transfected with human P-gp or MRP2 were used to establish concentration equilibrium transport assays (CETAs) and determine the transport profile of Hup-A. The expression of P-gp and MRP2 was detected by qPCR and western blotting. The transport function of P-gp and MRP2 was measured by Rho123 and CDFDA cell uptake assay.3. In CETAs, Hup-A at concentrations of 10 ng/mL or 2 µg/mL was transported by MDR1 and MRP2 from basolateral to apical sides of the cell monolayers. P-gp and MRP2 inhibitors completely blocked the efflux of Hup-A. There was no efflux of Hup-A in LLC-PK1 or MDCKII wild-type (WT) cells.4. We demonstrate that Hup-A is a substrate of P-gp and MRP2. These results imply the efflux of Hup-A across the blood-brain barrier (BBB) in vivo, suggesting potential drug resistance of Hup-A.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Alcaloides/metabolismo , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/metabolismo , Sesquiterpenos/metabolismo , Subfamilia B de Transportador de Casetes de Unión a ATP , Transporte Biológico , Barrera Hematoencefálica/metabolismo , Proteína 2 Asociada a Resistencia a Múltiples Medicamentos
13.
Plant Biotechnol J ; 17(9): 1823-1833, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-30811829

RESUMEN

Nitrogen (N) plays critical role in plant growth; manipulating N assimilation could be a target to increase grain yield and N use. Here, we show that ABRE-binding factor (ABF)-like leucine zipper transcription factor TabZIP60 mediates N use and growth in wheat. The expression of TabZIP60 is repressed when the N-deprived wheat plants is exposed to nitrate. Knock down of TabZIP60 through RNA interference (RNAi) increases NADH-dependent glutamate synthase (NADH-GOGAT) activity, lateral root branching, N uptake and spike number, and improves grain yield more than 25% under field conditions, while overexpression of TabZIP60-6D had the opposite effects. Further investigation shows TabZIP60 binds to ABRE-containing fragment in the promoter of TaNADH-GOGAT-3B and negatively regulates its expression. Genetic analysis reveals that TaNADH-GOGAT-3B overexpression overcomes the spike number and yield reduction caused by overexpressing TabZIP60-6D. As such, TabZIP60-mediated wheat growth and N use is associated with its negative regulation on TaNADH-GOGAT expression. These findings indicate that TabZIP60 and TaNADH-GOGAT interaction plays important roles in mediating N use and wheat growth, and provides valuable information for engineering N use efficiency and yield in wheat.


Asunto(s)
Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Nitrógeno/metabolismo , Proteínas de Plantas/genética , Factores de Transcripción/genética , Triticum/genética , Grano Comestible/crecimiento & desarrollo , Técnicas de Silenciamiento del Gen , Triticum/crecimiento & desarrollo
14.
Nanomedicine ; 18: 259-271, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30981817

RESUMEN

Chronic obstructive pulmonary disease (COPD) is partly characterized as epithelial-mesenchymal transition (EMT)-related airflow limitation. Extracellular vesicles (EVs) play crucial roles in the crosstalk between cells, affecting many diseases including COPD. Up to now, the roles of EVs in COPD are still debated. As we found in this investigation, COPD patients have higher miR-21 level in total serum EVs. EMT occurs in lungs of COPD mice. Furthermore, bronchial epithelial cells (BEAS-2B) could generate EVs with less miR-21 when treated with cigarette smoke extract (CSE), impacting less on the M2-directed macrophage polarization than the control-EVs (PBS-treated) according to EVs miR-21 level. Furthermore, the EMT processes in BEAS-2B cells were enhanced with the M2 macrophages proportion when co-cultured. Collectively, these results demonstrate that CSE-treated BEAS-2B cells could alleviate M2 macrophages polarization by modulated EVs, and eventually relieve the EMT process of BEAS-2B cells themselves under COPD pathogenesis, revealing a novel compensatory role of them in COPD.


Asunto(s)
Bronquios/patología , Polaridad Celular , Células Epiteliales/metabolismo , Transición Epitelial-Mesenquimal , Vesículas Extracelulares/metabolismo , Macrófagos/patología , Enfermedad Pulmonar Obstructiva Crónica/patología , Animales , Apoptosis , Línea Celular , Fumar Cigarrillos , Modelos Animales de Enfermedad , Vesículas Extracelulares/ultraestructura , Femenino , Humanos , Macrófagos/metabolismo , Masculino , Ratones Endogámicos C57BL , MicroARNs/sangre , Persona de Mediana Edad , Enfermedad Pulmonar Obstructiva Crónica/sangre
15.
BMC Plant Biol ; 18(1): 319, 2018 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-30509162

RESUMEN

BACKGROUND: High-molecular-weight glutenin subunits (HMW-GS) play important roles in the elasticity of dough made from wheat. The HMW-GS null line is useful for studying the contribution of HMW-GS to the end-use quality of wheat. METHODS: In a previous work, we cloned the Glu-1Ebx gene from Thinopyrum bessarabicum and introduced it into the wheat cultivar, Bobwhite. In addition to lines expressing the Glu-1Ebx gene, we also obtained a transgenic line (LH-11) with all the HMW-GS genes silenced. The HMW-GS deletion was stably inherited as a dominant and conformed to Mendel's laws. Expression levels of HMW-GS were determined by RT-PCR and epigenetic changes in methylation patterns and small RNAs were analyzed. Glutenins and gliadins were separated and quantitated by reversed-phase ultra-performance liquid chromatography. Measurement of glutenin macropolymer, and analysis of agronomic traits and end-use quality were also performed. RESULTS: DNA methylation and the presence of small double-stranded RNA may be the causes of post-transcriptional gene silencing in LH-11. The accumulation rate and final content of glutenin macropolymer (GMP) in LH-11 were significantly lower than in wild-type (WT) Bobwhite. The total protein content was not significantly affected as the total gliadin content increased in LH-11 compared to WT. Deletion of HMW-GS also changed the content of different gliadin fractions. The ratio of ω-gliadin increased, whereas α/ß- and γ-gliadins declined in LH-11. The wet gluten content, sedimentation value, development time and stability time of LH-11 were remarkably lower than that of Bobwhite. Bread cannot be made using the flour of LH-11. CONCLUSIONS: Post-transcriptional gene silencing through epigenetic changes and RNA inhibition appear to be the causes for the gene expression deficiency in the transgenic line LH-11. The silencing of HMW-GW in LH-11 significantly reduced the dough properties, GMP content, wet gluten content, sedimentation value, development time and stability time of flour made from this wheat cultivar. The HMW-GS null line may provide a potential material for biscuit-making because of its low dough strength.


Asunto(s)
Pan , Glútenes/metabolismo , Proteínas de Plantas/metabolismo , Triticum/metabolismo , Pan/normas , Culinaria , Metilación de ADN , Harina , Glútenes/genética , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente , Interferencia de ARN , Semillas/crecimiento & desarrollo , Semillas/metabolismo , Triticum/genética
16.
Plant Biotechnol J ; 16(11): 1858-1867, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29577547

RESUMEN

The plastidic glutamine synthetase isoform (GS2) plays a key role in nitrogen (N) assimilation. We introduced TaGS2-2Abpro::TaGS2-2Ab, the favourable allele of TaGS2-2A in the winter wheat (Triticum aestivum) variety Ji5265. Transgenic expression of TaGS2-2Ab significantly increased GS2 abundance and GS activity in leaves. Two consecutive field experiments showed the transgenic lines had higher grain yield, spike number, grain number per spike and 1000-grain weight than did the wild type under both low N and high N conditions. Analysis of N use-related traits showed that transgenic expression of TaGS2-2Ab increased root ability to acquire N, N uptake before and after flowering, remobilization of N to grains and N harvest index. Measurement of chlorophyll content and net photosynthesis rate in flag leaves during grain filling stage revealed that the transgenic lines had prolonged leaf functional duration as compared with the wild type. These results suggest that TaGS2 plays important role in N use, and the favourable allele TaGS2-2Ab is valuable in engineering wheat with improved N use efficiency and grain yield.


Asunto(s)
Producción de Cultivos , Glutamato-Amoníaco Ligasa/genética , Nitrógeno/metabolismo , Plantas Modificadas Genéticamente/genética , Triticum/genética , Clorofila/metabolismo , Producción de Cultivos/métodos , Glutamato-Amoníaco Ligasa/metabolismo , Fotosíntesis , Hojas de la Planta/enzimología , Hojas de la Planta/metabolismo , Plantas Modificadas Genéticamente/crecimiento & desarrollo , Plantas Modificadas Genéticamente/metabolismo , Plastidios/genética , Carácter Cuantitativo Heredable , Triticum/crecimiento & desarrollo , Triticum/metabolismo
17.
Plant Physiol ; 174(4): 2274-2288, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28626005

RESUMEN

Controlling the major auxin biosynthetic pathway to manipulate auxin content could be a target for genetic engineering of crops with desired traits, but little progress had been made because low or high auxin contents often cause developmental inhibition. Here, we performed a genome-wide analysis of bread wheat (Triticum aestivum) to identify the Tryptophan Aminotransferase of Arabidopsis1/Tryptophan Aminotransferase-Related (TAA1/TAR) genes that function in the tryptophan-dependent pathway of auxin biosynthesis. Sequence mining together with gene cloning identified 15 TaTAR genes, among which 12 and three genes were phylogenetically close to Arabidopsis (Arabidopsis thaliana) AtTAR2 and AtTAR3, respectively. TaTAR2.1 had the most abundant transcripts in the TaTAR2 genes and was expressed mainly in roots and up-regulated by low nitrogen (N) availability. Knockdown of TaTAR2.1 caused vegetative and reproductive deficiencies and impaired lateral root (LR) growth under both high- and low-N conditions. Overexpressing TaTAR2.1-3A in wheat enhanced LR branching, plant height, spike number, grain yield, and aerial N accumulation under different N supply levels. In addition, overexpressing TaTAR2.1-3A in Arabidopsis elevated auxin accumulation in the primary root tip, LR tip, LR primordia, and cotyledon and hypocotyl and increased primary root length, visible LR number, and shoot fresh weight under high- and low-N conditions. Our results indicate that TaTAR2.1 is critical for wheat growth and also shows potential for genetic engineering to reach the aim of improving the grain yield of wheat.


Asunto(s)
Vías Biosintéticas , Ácidos Indolacéticos/metabolismo , Semillas/enzimología , Triticum/enzimología , Triptófano-Transaminasa/metabolismo , Arabidopsis/efectos de los fármacos , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Biomasa , Vías Biosintéticas/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Técnicas de Silenciamiento del Gen , Genes de Plantas , Glucuronidasa/metabolismo , Nitrógeno/farmacología , Especificidad de Órganos/efectos de los fármacos , Especificidad de Órganos/genética , Fenotipo , Filogenia , Proteínas de Plantas/metabolismo , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/crecimiento & desarrollo , Brotes de la Planta/efectos de los fármacos , Brotes de la Planta/crecimiento & desarrollo , Plantas Modificadas Genéticamente , Plantones/efectos de los fármacos , Plantones/genética , Semillas/efectos de los fármacos , Triticum/efectos de los fármacos , Triticum/genética
18.
Biochim Biophys Acta ; 1852(8): 1561-73, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25912737

RESUMEN

A pathological hallmark of Alzheimer disease (AD) is the accumulation of misfolded hyperphosphorylated microtubule-associated protein Tau within neurons, forming neurofibrillary tangles and leading to synaptic dysfunction and neuronal death. Here we study sequence-dependent abnormal aggregation of human fragment Tau244-372 in an inducible cell model. As evidenced by confocal laser scanning microscopy, Western blot, and immunogold electron microscopy, fibril-forming motifs are essential and sufficient for abnormal aggregation of Tau244-372 in SH-SY5Y neuroblastoma cells induced by Congo red: when its two fibril-forming segments PHF6 and PHF6* are deleted, Tau244-372 does lose its ability to form fibrils in SH-SY5Y cells, and the replacement of PHF6 and PHF6* with an unrelated amyloidogenic sequence IFQINS from human lysozyme does rescue the fibril-forming ability of Tau244-372 in SH-SY5Y cells. By contrast, insertion of a non-fibril forming peptide GGGGGG does not drive the disabled Tau244-372 to misfold in SH-SY5Y cells. Furthermore, as revealed by quantum dots based probes combined with annexin V staining, annexin V-FITC apoptosis detection assay, and immunofluorescence, fibril-forming motifs are essential and sufficient for early apoptosis of living SH-SY5Y cells induced by abnormal aggregation of Tau244-372. Our results suggest that fibril-forming motifs could be the determinants of Tau protein tending to misfold in living cells, thereby inducing neuronal apoptosis and causing the initiation and development of AD.


Asunto(s)
Agregación Patológica de Proteínas , Dominios y Motivos de Interacción de Proteínas , Proteínas tau/química , Proteínas tau/genética , Proteínas tau/metabolismo , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Secuencia de Aminoácidos/fisiología , Línea Celular Tumoral , Células HEK293 , Humanos , Modelos Biológicos , Mutagénesis Insercional/fisiología , Ovillos Neurofibrilares/genética , Ovillos Neurofibrilares/metabolismo , Neuronas/metabolismo , Neuronas/patología , Fragmentos de Péptidos/química , Fragmentos de Péptidos/genética , Fragmentos de Péptidos/metabolismo , Agregación Patológica de Proteínas/genética , Agregación Patológica de Proteínas/metabolismo , Pliegue de Proteína , Dominios y Motivos de Interacción de Proteínas/genética , Eliminación de Secuencia/fisiología , Transfección , Regulación hacia Arriba/genética
19.
Microbiol Spectr ; 12(1): e0186823, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38018983

RESUMEN

IMPORTANCE: The link between gut microbiota and diet is crucial in the development of non-alcoholic steatohepatitis (NASH). This study underscores the essential role of a healthy diet in preventing and treating NASH by reversing obesity, lipidemia, and gut microbiota dysbiosis. Moreover, the supplementation of functional food or drug to the diet can provide additional advantages by inhibiting hepatic inflammation through the modulation of the hepatic inflammasome signaling pathway and partially mediating the gut microbiota and lipopolysaccharide signaling pathway. This study highlights the importance of adopting healthy dietary habits in treating NASH and proposes that supplementing with ginger essential oil or obeticholic acid may offer additional benefits. Nonetheless, further clinical studies are necessary to validate these findings.


Asunto(s)
Microbioma Gastrointestinal , Enfermedad del Hígado Graso no Alcohólico , Humanos , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Dieta Saludable , Dieta Alta en Grasa/efectos adversos , Hígado/metabolismo
20.
Sci Immunol ; 9(94): eadi8039, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38579013

RESUMEN

Vaccine adjuvants increase the breadth of serum antibody responses, but whether this is due to the generation of antigen-specific B cell clones with distinct specificities or the maturation of memory B cell clones that produce broadly cross-reactive antibodies is unknown. Here, we longitudinally analyzed immune responses in healthy adults after two-dose vaccination with either a virus-like particle COVID-19 vaccine (CoVLP), CoVLP adjuvanted with AS03 (CoVLP+AS03), or a messenger RNA vaccination (mRNA-1273). CoVLP+AS03 enhanced the magnitude and durability of circulating antibodies and antigen-specific CD4+ T cell and memory B cell responses. Antigen-specific CD4+ T cells in the CoVLP+AS03 group at day 42 correlated with antigen-specific memory B cells at 6 months. CoVLP+AS03 induced memory B cell responses, which accumulated somatic hypermutations over 6 months, resulting in enhanced neutralization breadth of monoclonal antibodies. Furthermore, the fraction of broadly neutralizing antibodies encoded by memory B cells increased between day 42 and 6 months. These results indicate that AS03 enhances the antigenic breadth of B cell memory at the clonal level and induces progressive maturation of the B cell response.


Asunto(s)
COVID-19 , Vacunas contra la Influenza , Gripe Humana , Polisorbatos , Escualeno , alfa-Tocoferol , Adulto , Humanos , Células B de Memoria , Vacunas contra la COVID-19 , Anticuerpos Antivirales , COVID-19/prevención & control , Combinación de Medicamentos
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