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1.
EMBO Rep ; 24(1): e55542, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36394374

RESUMO

The Zn content in cereal seeds is an important trait for crop production as well as for human health. However, little is known about how Zn is loaded to plant seeds. Here, through a genome-wide association study (GWAS), we identify the Zn-NA (nicotianamine) transporter gene ZmYSL2 that is responsible for loading Zn to maize kernels. High promoter sequence variation in ZmYSL2 most likely drives the natural variation in Zn concentrations in maize kernels. ZmYSL2 is specifically localized on the plasma membrane facing the maternal tissue of the basal endosperm transfer cell layer (BETL) and functions in loading Zn-NA into the BETL. Overexpression of ZmYSL2 increases the Zn concentration in the kernels by 31.6%, which achieves the goal of Zn biofortification of maize. These findings resolve the mystery underlying the loading of Zn into plant seeds, providing an efficient strategy for breeding or engineering maize varieties with enriched Zn nutrition.


Assuntos
Estudo de Associação Genômica Ampla , Zea mays , Humanos , Zea mays/genética , Zea mays/metabolismo , Zinco/metabolismo , Melhoramento Vegetal , Sementes/genética , Proteínas de Membrana Transportadoras/genética
2.
Plant J ; 105(6): 1689-1702, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33354819

RESUMO

Adventitious roots (ARs) are an important root type for plants and display a high phenotypic plasticity in response to different environmental stimuli. Previous studies found that dark-light transition can trigger AR formation from the hypocotyl of etiolated Arabidopsis thaliana, which was used as a model for the identification of regulators of AR biogenesis. However, the central regulatory machinery for darkness-induced hypocotyl AR (HAR) remains elusive. Here, we report that photoreceptors suppress HAR biogenesis through regulating the molecular module essential for lateral roots. We found that hypocotyls embedded in soil or in continuous darkness are able to develop HARs, wherein photoreceptors act as negative regulators. Distinct from wound-induced ARs that require WOX11 and WOX12, darkness-induced HARs are fully dependent on ARF7, ARF19, WOX5/7, and LBD16. Further studies established that PHYB interacts with IAA14, ARF7, and ARF9. The interactions stabilize IAA14 and inhibit the transcriptional activities of ARF7 and ARF19 and thus suppress biogenesis of darkness-induced HARs. This finding not only revealed the central machinery controlling HAR biogenesis but also illustrated that AR formation could be initiated by multiple pathways.


Assuntos
Proteínas de Arabidopsis/metabolismo , Hipocótilo/crescimento & desenvolvimento , Hipocótilo/metabolismo , Fitocromo B/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Escuridão , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos/metabolismo , Transdução de Sinais , Fatores de Transcrição/genética
3.
New Phytol ; 236(5): 1655-1660, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36093736

RESUMO

Iron (Fe) homeostasis is essential for both plant development and human nutrition. The maintenance of Fe homeostasis involves a complex network in which Fe signaling nodes and circuits coordinate tightly Fe transporters, ferric reductases, H+ -ATPases, low-molecular-mass metal chelators, and transporters of chelators and Fe-chelate complexes. Early-stage studies have revealed different strategies for Fe homeostasis between graminaceous and nongraminaceous plants. Recent progress has refreshed our understanding of previous knowledge, especially on the uptake, phloem transport and systemic signaling of Fe. This review attempts to summarize recent exciting and potentially influential studies on the various routes of Fe uptake and distribution in plants, focusing on breakthroughs that have changed our understanding of plant Fe nutrition.


Assuntos
Ferro , Plantas , Transporte Biológico , Quelantes , Regulação da Expressão Gênica de Plantas , Homeostase , Ferro/metabolismo , Plantas/metabolismo , ATPases Translocadoras de Prótons
4.
New Phytol ; 235(4): 1486-1500, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35510797

RESUMO

Protein sorting is an essential biological process in all organisms. Trafficking membrane proteins generally relies on the sorting machinery of the Golgi apparatus. However, many proteins have been found to be delivered to target locations via Golgi-independent pathways, but the mechanisms underlying this delivery system remain unknown. Here, we report that Sec24C mediates the direct secretory trafficking of the phytochelatin transporters ABCC1 and ABCC2 from the endoplasmic reticulum (ER) to prevacuolar compartments (PVCs) in Arabidopsis thaliana. Genetic analysis showed that the sec24c mutants are hypersensitive to cadmium (Cd) and arsenic (As) treatments due to mislocalisation of ABCC1 and ABCC2, which results in defects in the vacuole compartmentalisation of the toxic metals. Furthermore, we found that Sec24C recognises ABCC1 and ABCC2 through direct interactions to mediate their exit from the ER to PVCs, which is independent of brefeldin A-sensitive post-Golgi trafficking pathway. These findings expand our understanding of Golgi-independent trafficking, which also provide key insights regarding the mechanism of tonoplast protein sorting and open a new perspective on the function of Sec24 proteins.


Assuntos
Arabidopsis , Fenômenos Biológicos , Arabidopsis/genética , Arabidopsis/metabolismo , Retículo Endoplasmático/metabolismo , Complexo de Golgi/metabolismo , Transporte Proteico , Vacúolos/metabolismo
5.
J Comput Chem ; 42(27): 1929-1943, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34382702

RESUMO

In this paper, an improved Poisson-Nernst-Planck ion channel (PNPic) model is presented, along with its effective finite element solver and software package for an ion channel protein in a solution of multiple ionic species. Numerical studies are then done on the effects of boundary value conditions, membrane charges, and bulk concentrations on electrostatics and ionic concentrations for an ion channel protein, a gramicidin A (gA), and five different ionic solvents with up to four species. Numerical results indicate that the cation selectivity property of gA occurs within a central portion of ion channel pore, insensitively to any change of boundary value condition, membrane charge, or bulk concentration. Moreover, a numerical scheme for computing the electric currents induced by ion transports across membrane via an ion channel pore is presented and implemented as a part of the PNPic finite element package. It is then applied to the calculation of current-voltage curves, well validating the PNPic model and finite element package by electric current experimental data.

6.
J Digit Imaging ; 34(5): 1264-1278, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34508300

RESUMO

Maximum intensity projection (MIP) technology is a computer visualization method that projects three-dimensional spatial data on a visualization plane. According to the specific purposes, the specific lab thickness and direction can be selected. This technology can better show organs, such as blood vessels, arteries, veins, and bronchi and so forth, from different directions, which could bring more intuitive and comprehensive results for doctors in the diagnosis of related diseases. However, in this traditional projection technology, the details of the small projected target are not clearly visualized when the projected target is not much different from the surrounding environment, which could lead to missed diagnosis or misdiagnosis. Therefore, it is urgent to develop a new technology that can better and clearly display the angiogram. However, to the best of our knowledge, research in this area is scarce. To fill this gap in the literature, in the present study, we propose a new method based on the hybrid of convolutional neural network (CNN) and radial basis function neural network (RBFNN) to synthesize the projection image. We first adopted the U-net to obtain feature or enhanced images to be projected; subsequently, the RBF neural network performed further synthesis processing for these data; finally, the projection images were obtained. For experimental data, in order to increase the robustness of the proposed algorithm, the following three different types of datasets were adopted: the vascular projection of the brain, the bronchial projection of the lung parenchyma, and the vascular projection of the liver. In addition, radiologist evaluation and five classic metrics of image definition were implemented for effective analysis. Finally, compared to the traditional MIP technology and other structures, the use of a large number of different types of data and superior experimental results proved the versatility and robustness of the proposed method.


Assuntos
Algoritmos , Redes Neurais de Computação , Encéfalo , Humanos , Processamento de Imagem Assistida por Computador , Pulmão , Tecnologia
7.
Bioorg Med Chem ; 28(9): 115438, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32199689

RESUMO

Endomorphin (EM)-1 and EM-2 are the most effective endogenous analgesics with efficient separation of analgesia from the risk of adverse effects. Poor metabolic stability and ineffective analgesia after peripheral administration were detrimental for the use of EMs as novel clinical analgesics. Therefore, here, we aimed to establish new EM analogs via introducing different bifunctional d-amino acids at position 2 of [(2-furyl)Map4]EMs. The combination of [(2-furyl)Map4]EMs with D-Arg2 or D-Cit2 yielded analogs with enhanced binding affinity to the µ-opioid receptor (MOR) and increased stability against enzymatic degradation (t1/2 > 300 min). However, the agonistic activities of these analogs toward MOR were slightly reduced. Similar to morphine, peripheral administration of the analog [D-Cit2, (2-furyl)Map4]EM-1 (10) significantly inhibited the pain behavior of mice in multiple pain models. In addition, this EM-1 analog was associated with reduced tolerance, less effect on gastrointestinal mobility, and no significant motor impairment. Compared to natural EMs, the EM analogs synthesized herein had enhanced metabolic stability, bioavailability, and analgesic properties.


Assuntos
Analgésicos Opioides/farmacologia , Desenho de Fármacos , Oligopeptídeos/farmacologia , Dor/tratamento farmacológico , Receptores Opioides mu/agonistas , Animais , Relação Dose-Resposta a Droga , Formaldeído , Masculino , Camundongos , Camundongos Endogâmicos , Estrutura Molecular , Dor/induzido quimicamente , Medição da Dor , Relação Estrutura-Atividade
8.
PLoS Genet ; 13(10): e1007086, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29084222

RESUMO

Arabidopsis thaliana high-affinity potassium transporter 1 (AtHKT1) limits the root-to-shoot sodium transportation and is believed to be essential for salt tolerance in A. thaliana. Nevertheless, natural accessions with 'weak allele' of AtHKT1, e.g. Tsu-1, are mainly distributed in saline areas and are more tolerant to salinity. These findings challenge the role of AtHKT1 in salt tolerance and call into question the involvement of AtHKT1 in salinity adaptation in A. thaliana. Here, we report that AtHKT1 indeed drives natural variation in the salt tolerance of A. thaliana and the coastal AtHKT1, so-called weak allele, is actually hyper-functional in reducing flowers sodium content upon salt stress. Our data showed that AtHKT1 positively contributes to saline adaptation in a linear manner. Forward and reverse genetics analysis established that the single AtHKT1 locus is responsible for the variation in the salinity adaptation between Col-0 and Tsu-1. Reciprocal grafting experiments revealed that shoot AtHKT1 determines the salt tolerance of Tsu-1, whereas root AtHKT1 primarily drives the salt tolerance of Col-0. Furthermore, evidence indicated that Tsu-1 AtHKT1 is highly expressed in stems and is more effective compared to Col-0 AtHKT1 at limiting sodium flow to the flowers. Such efficient retrieval of sodium to the reproductive organ endows Tsu-1 with stronger fertility compared to Col-0 upon salt stress, thus improving Tsu-1 adaptation to a coastal environment. To conclude, our data not only confirm the role of AtHKT1 in saline adaptation, but also sheds light on our understanding of the salt tolerance mechanisms in plants.


Assuntos
Adaptação Fisiológica/genética , Proteínas de Arabidopsis/genética , Arabidopsis/genética , Proteínas de Transporte de Cátions/genética , Flores/genética , Tolerância ao Sal/genética , Sódio/metabolismo , Simportadores/genética , Alelos , Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Salinidade , Cloreto de Sódio/metabolismo
9.
J Appl Clin Med Phys ; 19(3): 301-309, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29493082

RESUMO

Dose reduction techniques have been studied in medical imaging. We propose shutter scan acquisition for region of interest (ROI) imaging to reduce the patient exposure dose received from a digital tomosynthesis system. A prototype chest digital tomosynthesis (CDT) system (LISTEM, Wonju, Korea) and the LUNGMAN phantom (Kyoto Kagaku, Japan) with lung nodules 8, 10, and 12 mm in size were used for this study. A total of 41 projections with shutter scan acquisition consisted of 21 truncated projections and 20 non-truncated projections. For comparison, 41 projections using conventional full view scan acquisition were also acquired. Truncated projections obtained by shutter scan acquisition were corrected by proposed image processing procedure to remove the truncation artifacts. The image quality was evaluated using the contrast to noise ratio (CNR), coefficient of variation (COV), and figure of merit (FOM). We measured the dose area product (DAP) value to verify the dose reduction using shutter scan acquisition. The ROI of the reconstructed image from shutter scan acquisition showed enhanced contrast. The results showed that CNR values of 8 and 12 mm lung nodules increased by 6.38% and 21.21%, respectively, and the CNR value of 10 mm lung nodule decreased by 3.63%. COV values of the lung nodules were lower in a shutter scan image than in a full view scan image. FOM values of 8, 10, and 12 mm lung nodules increased by 3.06, 2.25, and 2.33 times, respectively. This study compared the proposed shutter scan and conventional full view scan acquisition. In conclusion, using a shutter scan acquisition method resulted in enhanced contrast images within the ROI and higher FOM values. The patient exposure dose of the proposed shutter scan acquisition method can be reduced by limiting the field of view (FOV) to focus on the ROI.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/radioterapia , Processamento de Imagem Assistida por Computador/métodos , Mamografia/métodos , Órgãos em Risco/efeitos da radiação , Imagens de Fantasmas , Estudos de Viabilidade , Feminino , Humanos , Dosagem Radioterapêutica
10.
Opt Lett ; 39(13): 3907-10, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24978768

RESUMO

Dynamic laser speckles contain motion information of scattering particles which can be estimated by laser speckle contrast analysis (LASCA). In this work, an entropy-based method was proposed to provide a more robust estimation of motion speed. An in vitro flow simulation experiment confirmed a simple linear relation between entropy, exposure time, and speed. A multimodality optical imaging setup is developed to validate the advantages of the entropy method based on laser speckle imaging, green light imaging, and fluorescence imaging. The entropy method overcomes traditional LASCA with less noisy interference, and extracts more visible and detailed vasculatures in vivo. Furthermore, the entropy method provides a more accurate estimation and a stable pattern of blood flow activations in the rat's somatosensory area under multitrial hand paw stimulations.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Lasers , Espalhamento de Radiação , Animais , Circulação Cerebrovascular , Meios de Contraste , Entropia , Feminino , Hemorreologia , Interferometria , Modelos Lineares , Modelos Cardiovasculares , Imagem Óptica , Fenômenos Ópticos , Ratos , Ratos Sprague-Dawley , Córtex Somatossensorial/irrigação sanguínea
11.
World J Surg Oncol ; 12: 121, 2014 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-24766948

RESUMO

BACKGROUND: The aim of the present study was to investigate the expression of glucose-related protein 78 (GRP78) and heparanase (HPA) in oral squamous cell carcinoma (OSCC) and their relationship with clinicopathological parameters and potential implications for survival. METHODS: A total of 46 patients with OSCC and 10 normal individuals were recruited for the study. GRP78 and HPA expression were determined in the lesion tissues using immunohistochemical analysis. The correlation between GRP78 and HPA was assessed using the Spearman correlation analysis. The associations of GRP78 and HPA with clinicopathological characteristics and survival were examined using the x2-test, Kaplan-Meier, or Cox regression. RESULTS: Patients with OSCC showed a statistically significant higher prevalence of GRP78 and HPA expression than normal oral tissues. GRP78 and HPA expression was positively correlated with size, TNM stage, histological grade, lymphatic metastasis, and distant metastasis in OSCC patients. GRP78 expression was also positively correlated with HPA expression. Positive GRP78 and HPA expression was inversely correlated with survival in OSCC patients. CONCLUSIONS: HPA expression was found to be positively correlated with GRP78 expression. GRP78 and HPA are biomarkers that may have the potential to guide the treatment of oral cancer patients.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/secundário , Glucuronidase/metabolismo , Proteínas de Choque Térmico/metabolismo , Neoplasias Bucais/patologia , Boca/metabolismo , Adolescente , Adulto , Idoso , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/mortalidade , Estudos de Casos e Controles , Criança , Pré-Escolar , Chaperona BiP do Retículo Endoplasmático , Feminino , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/metabolismo , Neoplasias Bucais/mortalidade , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Adulto Jovem
12.
Yi Chuan ; 35(11): 1307-16, 2013 Nov.
Artigo em Zh | MEDLINE | ID: mdl-24579314

RESUMO

MicroRNAs (miRNAs) are a class of short non-coding RNAs found widely in eukaryotic organisms. The ptc-MIR169 gene family, which consists of 33 members, is the largest miRNA gene family in poplar (Populus trichocarpa) It is significant to analyze the evolution of the ptc-MIR169 gene family in order to understand the evolutionary mechanisms of miRNAs in poplar. In the present study, we investigated the molecular phylogeny, duplication, expression and target genes of the MIR169 gene family in poplar. Both tandem duplications and chromosome segmental duplications contributed to the expanding of ptc-MIR169 gene family, and the expression patterns diversified obviously among the gene family. These findings suggest that the ptc-MIR169 gene family is involved in complex regulatory networks, and plays significant roles in development and stress response in poplar. This paper provides a reference for the evolutionary study of miRNAs in poplar and related species in Salicaceae.


Assuntos
Evolução Molecular , MicroRNAs/genética , Família Multigênica , Populus/genética , RNA de Plantas/genética , Duplicação Gênica , Filogenia , Plantas/classificação , Plantas/genética , Populus/classificação
13.
Front Immunol ; 14: 1251645, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37799725

RESUMO

Immune checkpoint inhibitors (ICIs) modulate the body's immune function to treat tumors but may also induce pneumonitis. Immune checkpoint inhibitor-related pneumonitis (ICIP) is a serious immune-related adverse event (irAE). Immunotherapy is currently approved as a first-line treatment for non-small cell lung cancer (NSCLC), and the incidence of ICIP in NSCLC patients can be as high as 5%-19% in clinical practice. ICIP can be severe enough to lead to the death of NSCLC patients, but there is a lack of a gold standard for the diagnosis of ICIP. Radiomics is a method that uses computational techniques to analyze medical images (e.g., CT, MRI, PET) and extract important features from them, which can be used to solve classification and regression problems in the clinic. Radiomics has been applied to predict and identify ICIP in NSCLC patients in the hope of transforming clinical qualitative problems into quantitative ones, thus improving the diagnosis and treatment of ICIP. In this review, we summarize the pathogenesis of ICIP and the process of radiomics feature extraction, review the clinical application of radiomics in ICIP of NSCLC patients, and discuss its future application prospects.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Pneumonia , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Inibidores de Checkpoint Imunológico/efeitos adversos , Neoplasias Pulmonares/tratamento farmacológico , Pneumonia/diagnóstico , Pneumonia/diagnóstico por imagem , Imunoterapia/efeitos adversos
14.
Hortic Res ; 10(1): uhac244, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36643750

RESUMO

Increasing soil salinization seriously impairs plant growth and development, resulting in crop loss. The Salt-Overly-Sensitive (SOS) pathway is indispensable to the mitigation of Na + toxicity in plants under high salinity. However, whether natural variations of SOS2 contribute to salt tolerance has not been reported. Here a natural variation in the SlSOS2 promoter region was identified to be associated with root Na+/K+ ratio and the loss of salt resistance during tomato domestication. This natural variation contains an ABI4-binding cis-element and plays an important role in the repression of SlSOS2 expression. Genetic evidence revealed that SlSOS2 mutations increase root Na+/K+ ratio under salt stress conditions and thus attenuate salt resistance in tomato. Together, our findings uncovered a critical but previously unknown natural variation of SOS2 in salt resistance, which provides valuable natural resources for genetic breeding for salt resistance in cultivated tomatoes and other crops.

15.
Curr Biol ; 33(24): 5355-5367.e5, 2023 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-37995699

RESUMO

Soybean (Glycine max) is a crop with high demand for molybdenum (Mo) and typically requires Mo fertilization to achieve maximum yield potential. However, the genetic basis underlying the natural variation of Mo concentration in soybean and its impact on soybean agronomic performance is still poorly understood. Here, we performed a genome-wide association study (GWAS) to identify GmMOT1.1 and GmMOT1.2 that drive the natural variation of soybean Mo concentration and confer agronomic traits by affecting auxin synthesis. The soybean population exhibits five haplotypes of the two genes, with the haplotype 5 demonstrating the highest expression of GmMOT1.1 and GmMOT1.2, as well as the highest transport activities of their proteins. Further studies showed that GmMOT1.1 and GmMOT1.2 improve soybean yield, especially when cultivated in acidic or slightly acidic soil. Surprisingly, these two genes contribute to soybean growth by enhancing the activity of indole-3-acetaldehyde (IAAld) aldehyde oxidase (AO), leading to increased indole-3-acetic acid (IAA) synthesis, rather than being involved in symbiotic nitrogen fixation or nitrogen assimilation. Furthermore, the geographical distribution of five haplotypes in China and their correlation with soil pH suggest the potential significance of GmMOT1.1 and GmMOT1.2 in soybean breeding strategies.


Assuntos
Glycine max , Molibdênio , Glycine max/genética , Molibdênio/metabolismo , Estudo de Associação Genômica Ampla , Melhoramento Vegetal , Ácidos Indolacéticos/metabolismo , Solo
16.
Eur J Pharmacol ; 961: 176182, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37951488

RESUMO

Opioids are widely used in the treatment of moderate and severe pain. Nociceptive stimulation has been reported to potentially promote microglial activation and neuroinflammation, which also causes chronic pain sensitization. The aim of this study was to demonstrate whether the novel µ receptor agonist MEL-0614 could inhibit activated microglia directly and the associated signaling pathway. Mice were administered lipopolysaccharide and formalin to induce allodynia. Von Frey test was used to detect the anti-allodynia effect of MEL-0614 before and after LPS and formalin injection. In the spinal cord, the levels of proinflammatory cytokines and microglial activation were determined after MEL-0614 administration. BV2 and primary microglia were cultured to further explore the effect of MEL-0614 on LPS-induced microglial activation and key signaling pathways involved. MEL-0614 partially prevented and reversed allodynia induced by LPS and formalin in vivo, which was not inhibited by the µ receptor antagonist CTAP. Minocycline was effective in reversing the established allodynia. MEL-0614 also downregulated the activation of microglia and related proinflammatory cytokines in the spinal cord. Additionally, in BV2 and primary microglia, MEL-0614 inhibited the LPS-induced upregulation of proinflammatory factors, which was unaffected by CTAP. The NLR family pyrin domain containing 3 (NLRP3) related signaling pathway may be involved in the interaction between MEL-0614 and microglia. The opioid agonist MEL-0614 inhibited the activation of microglia and the subsequent upregulation of proinflammatory factors both in vivo and in vitro. Notably, this effect is partially mediated by the µ receptor.


Assuntos
Hiperalgesia , Microglia , Camundongos , Animais , Hiperalgesia/metabolismo , Receptores Opioides mu/metabolismo , Lipopolissacarídeos/farmacologia , Dor/induzido quimicamente , Citocinas/metabolismo , Formaldeído/efeitos adversos
17.
Mol Plant ; 15(1): 167-178, 2022 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-34530166

RESUMO

Nitrogen is an essential nutrient for plant growth and development, and plays vital roles in crop yield. Assimilation of nitrogen is thus fine-tuned in response to heterogeneous environments. However, the regulatory mechanism underlying this essential process remains largely unknown. Here, we report that a zinc-finger transcription factor, drought and salt tolerance (DST), controls nitrate assimilation in rice by regulating the expression of OsNR1.2. We found that loss of function of DST results in a significant decrease of nitrogen use efficiency (NUE) in the presence of nitrate. Further study revealed that DST is required for full nitrate reductase activity in rice and directly regulates the expression of OsNR1.2, a gene showing sequence similarity to nitrate reductase. Reverse genetics and biochemistry studies revealed that OsNR1.2 encodes an NADH-dependent nitrate reductase that is required for high NUE of rice. Interestingly, the DST-OsNR1.2 regulatory module is involved in the suppression of nitrate assimilation under drought stress, which contributes to drought tolerance. Considering the negative role of DST in stomata closure, as revealed previously, the positive role of DST in nitrogen assimilation suggests a mechanism coupling nitrogen metabolism and stomata movement. The discovery of this coupling mechanism will aid the engineering of drought-tolerant crops with high NUE in the future.


Assuntos
Adaptação Fisiológica/genética , Secas , Nitrato Redutase/genética , Nitrato Redutase/metabolismo , Nitrogênio/metabolismo , Oryza/crescimento & desenvolvimento , Oryza/genética , Oryza/metabolismo , Produtos Agrícolas/genética , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Variação Genética , Genótipo , Tolerância ao Sal/genética , Fatores de Transcrição/efeitos dos fármacos , Dedos de Zinco/efeitos dos fármacos
18.
J Ethnopharmacol ; 293: 115210, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35398501

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The AnluoHuaxian pill (AHP) is a widely used patented medicine for chronic hepatitis B (CHB) patients with advanced fibrosis or cirrhosis that has been used in China for more than 15 years. However, data are lacking on whether monotherapy with AHP can be effective in CHB patients with alanine aminotransferase (ALT) levels less than 2 times the upper limit of normal (ALT<2ULN) and early liver fibrosis (F ≤ 2). AIM OF THE STUDY: We aimed to investigate whether monotherapy with AHP improves liver histology in these patients. MATERIALS AND METHODS: In this double-blind, randomized, placebo-controlled trial, 270 CHB patients with ALT<2ULN and F ≤ 2 were treated in 12 hospitals in China. The patients were randomly assigned to an intervention (AHP) group and a placebo group at a ratio of 2:1. Of these 270 enrolled patients, 147 had paired liver biopsies. The primary end point was histological change after 48 weeks of treatment. RESULTS: Per-protocol analysis revealed that the rate of histologic improvement in liver fibrosis patients in the AHP group was significantly higher than that in the placebo group (37.7% vs. 19.5%, P = 0.035) after 48 weeks of treatment, which was consistent with results from intention-to-treat and sensitivity analyses. Moreover, after adjusting for baseline characteristics, AHP was superior to placebo with respect to improving liver fibrosis (odds ratio [OR] = 2.58, 95% confidence interval [CI]: (1.01, 6.63),P = 0.049) and liver histology (OR = 3.62, 95% CI: (1.42, 9.20),P = 0.007). In noninvasive measurement of liver fibrosis (FibroScan®), the level of liver stiffness measurement (LSM) had decreased significantly at 48 weeks (5.1 kPa) compared with that at baseline (5.7 kPa) (P = 0.008) in the AHP group, whereas it did not decrease significantly in the placebo group. Cirrhosis developed in one patient in the placebo group but in no patients in the AHP group. No serious side effects occurred in the AHP-treated patients. CONCLUSIONS: Treatment of CHB patients who had ALT<2ULN and F ≤ 2 with the traditional Chinese medicine AHP for 48 weeks improves liver fibrosis. However, due to the short duration of treatment and the limited sample size of liver pathology, the long-term benefits of AHP in reducing fibrosis and the risk of cirrhosis and hepatocellular carcinoma in these patients need to be further studied in the future.


Assuntos
Hepatite B Crônica , Alanina/uso terapêutico , Alanina Transaminase , Medicamentos de Ervas Chinesas , Hepatite B Crônica/tratamento farmacológico , Humanos , Fígado/patologia , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/patologia
19.
Yi Chuan ; 33(7): 801-6, 2011 Jul.
Artigo em Zh | MEDLINE | ID: mdl-22049696

RESUMO

Genomics is an important subdiscipline of genetics, and it forms a complete research system based on novel theories and techniques. Incorporating genomics in undergraduate curriculum is a response to the need of the development of genetics. The teaching of genomics has significant advantages on developing scientific thinking, enhances bioethics accomplishment, and professional interests in undergraduate students. The integration of genomics into genetics is in accordance with the principles of subject development and education. Related textbooks for undergraduate education are currently available in China, and it is feasible to set up a genetics and genomics integrative course by modifying teaching contents of the genetics course, selecting appropriate teaching approaches, and optimal application of the computer-assisted instruction.


Assuntos
Genética/educação , Genômica/educação , China , Instrução por Computador , Currículo , Humanos
20.
Sci Adv ; 7(36): eabh2450, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34516912

RESUMO

Accumulation of iron in seeds is essential for both plant reproduction and human nutrition. Transport of iron to seeds requires the chelator nicotianamine (NA) to prevent its precipitation in the plant vascular tissues. However, how NA is transported to the apoplast for forming metal-NA complexes remains unknown. Here, we report that two members of the nitrate/peptide transporter family, NAET1 and NAET2, function as NA transporters required for translocation of both iron and copper to seeds. We show that NAET1 and NAET2 are predominantly expressed in the shoot and root vascular tissues and mediate secretion of NA out of the cells in resembling the release of neurotransmitters from animal synaptic vesicles. These findings reveal an unusual mechanism of transmembrane transport in plants and uncover a fundamental aspect of plant nutrition that has implications for improving food nutrition and human health.

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