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1.
Langmuir ; 40(13): 7242-7248, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38501957

RESUMEN

The metal-thiol interface is ubiquitous in nanotechnology and surface chemistry. It is not only used to construct nanocomposites but also plays a decisive role in the properties of these materials. When organothiol molecules bind to the gold surface, there is still controversy over whether sulfhydryl groups can form disulfide bonds and whether these disulfide bonds can remain stable on the gold surface. Here, we investigate the intrinsic properties of sulfhydryl groups on the gold surface at the single-molecule level using a scanning tunneling microscope break junction technique. Our findings indicate that sulfhydryl groups can react with each other to form disulfide bonds on the gold surface, and the electric field can promote the sulfhydryl coupling reaction. In addition to these findings, ultraviolet irradiation is used to effectively regulate the coupling between sulfhydryl groups, leading to the formation and cleavage of disulfide bonds. These results unveil the intrinsic properties of sulfhydryl groups on the gold surface, therefore facilitating the accurate construction of broad nanocomposites with the desired functionalities.

2.
J Sleep Res ; 32(3): e13762, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36325765

RESUMEN

Sleep-disordered breathing (SDB) is highly prevalent, but its rates of diagnosis and treatment are low. As a heterogeneous condition, it is associated with delayed diagnosis and/or suboptimal treatment. We aimed to determine distinct SDB clusters and examine their association with medical care-seeking behaviour and sleep habits in a community-dwelling population in South China. Participants were enrolled in the 'Guangdong Sleep Health Study'. Five distinct community sites were investigated. Participant information was collected, and overnight sleep monitoring was performed. Latent class analysis was performed to classify patients with SDB based on patterns of SDB-related symptoms and signs. Overall, 1,524 patients with SDB were evaluated. Four distinct clusters were identified: 'minimally symptomatic' (Cluster 2), which was the most dominant subtype (41.6%), followed by 'pure insomnia/fewer daytime symptoms' (Cluster 4; 24.7%), 'insomnia/multiple daytime symptoms' (Cluster 3; 17.8%), and 'upper airway symptoms with sleepiness' (Cluster 1; 15.9%). The overall medical care-seeking rate attributable to sleep and breathing disorders was only 3.3%: 10.3% in Cluster 3, 2.5% in Cluster 1, 2.1% in Cluster 4, and 1.3% in Cluster 2, in which Cluster 3 was the highest and Cluster 2 was the lowest (adjusted p < 0.05). Regarding the sleep habit of going to bed and waking up at a consistent time, Cluster 3 exhibited the worst performance and Cluster 2 the best. In conclusion, distinct phenotypic subtypes were identified in community-dwelling patients with SDB. Tailored strategies to encourage medical care-seeking, early identification, and optimisation of treatment are necessary considering the different subtypes.


Asunto(s)
Síndromes de la Apnea del Sueño , Trastornos del Inicio y del Mantenimiento del Sueño , Humanos , Polisomnografía , Trastornos del Inicio y del Mantenimiento del Sueño/complicaciones , Síndromes de la Apnea del Sueño/diagnóstico , Síndromes de la Apnea del Sueño/epidemiología , Síndromes de la Apnea del Sueño/terapia , Sueño , China/epidemiología
3.
Cell Mol Biol (Noisy-le-grand) ; 69(8): 221-225, 2023 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-37715381

RESUMEN

Lung cancer remains the leading cause of cancer morbidity and mortality worldwide, and over-diagnosis causes various unnecessary losses in patients' lives and health. How to more effectively screen lung cancer patients and their potential prognostic risk become the focus of our current study. By analyzing the LUAD expression profile in The Cancer Genome Atlas (TCGA), we constructed a weighted gene co-expression network using differentially expressed genes (DEGs) to find the key modules and pivotal genes. A COX proportional risk regression model based on the least absolute shrinkage and selection operator (LASSO) was used to assess the predictive value of the model for the prognosis of LUAD patients. A total of 4107 up-regulated DEGs and 2022 down-regulated DEGs were identified in this study, and enrichment analysis showed that these analyzes were associated with the extracellular matrix of cells and adhesion. Ten gene markers consisting of LDHA, TOP2A, UBE2C, TYMS, TRIP13, EXO1, TTK, TPX2, ZWINT, and UHRF1 were established by extracting the central genes in the key modules, and the upregulation of these genes was accompanied by an increased prognostic risk of patients. Among them, high expression of LDHA, TRIP13, and TTK in LUAD was associated with shorter overall survival and could be used as independent prognostic factors to participate in metabolic processes such as tumor NAD. The present study provides a powerful molecular target for the study of LUAD prognosis and provides a theoretical basis for the diagnosis and treatment of LUAD and the development of targeted inhibitors.


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Humanos , Pronóstico , Adenocarcinoma del Pulmón/genética , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Biología Computacional , Matriz Extracelular , Proteínas Potenciadoras de Unión a CCAAT , Ubiquitina-Proteína Ligasas , ATPasas Asociadas con Actividades Celulares Diversas , Proteínas de Ciclo Celular
4.
Sleep Breath ; 27(1): 205-212, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-35347656

RESUMEN

PURPOSE: Due to the lack of an objective population-based screening tool for obstructive sleep apnea (OSA), a large number of patients with potential OSA have not been identified in the general population. Our study compared an objective wearable sleep monitoring device with polysomnography (PSG) to provide a reference for OSA screening in a large population. METHODS: Using a self-control method, patients admitted to our sleep center from July 2020 to March 2021 were selected for overnight PSG and wearable intelligent sleep monitor (WISM) at the same time. The sensitivity and specificity of the device for the diagnosis of OSA were evaluated. RESULTS: A total of 196 participants (mean age: 45.1 ± 12.3 years [18-80 years]; 168 men [86%]) completed both PSG and WISM monitoring. Using an apnea-hypopnea index (AHI) ≥ 5 events/h as the diagnostic criterion, the sensitivity, specificity, kappa value, and area under the receiver operating characteristic curve of the WISM for OSA diagnosis were 93%, 77%, 0.6, and 0.95, respectively. Using an AHI ≥ 15 events/h as the diagnostic criterion for moderate-to-severe OSA, these values were 92%, 89%, 0.8, and 0.95, respectively. The mean difference in the AHI between PSG and the artificial intelligence oxygen desaturation index from the WISM was 6.8 events/h (95% confidence interval: - 13.1 to 26.7). CONCLUSION: Compared with the PSG, WISM exhibits good sensitivity and specificity for the diagnosis of OSA. This small, simple, and easy-to-use device is more suitable for OSA screening in a large population because of its single-step application procedure.


Asunto(s)
Apnea Obstructiva del Sueño , Dispositivos Electrónicos Vestibles , Masculino , Humanos , Adulto , Persona de Mediana Edad , Polisomnografía , Inteligencia Artificial , Sueño , Apnea Obstructiva del Sueño/diagnóstico
5.
Sleep Breath ; 27(2): 511-518, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-35562555

RESUMEN

PURPOSE: To evaluate the effect of long-term continuous positive airway pressure (CPAP) treatment on disease severity of obstructive sleep apnea (OSA). METHODS: We analyzed results from the Sleep Apnea and Cardiovascular Events (SAVE) study involving participants recruited at the Guangdong Provincial People's Hospital, China. Participants were aged 45-75 years with a history of cardiac or cerebrovascular disease. OSA was confirmed by home sleep apnea testing (HSAT). Participants were randomized to receive CPAP plus standard cardiovascular care (CPAP group) or standard care alone (UC group) and followed for several years. At the study conclusion, surviving participants were invited to repeat HSAT. Changes in OSA indicators were compared by independent samples t-tests and subgroup analysis was implied among groups stratified by OSA severity. RESULTS: One hundred two adults were recruited (51 per group) and followed for 48.0 ± 14.5 months. Daily CPAP usage in the CPAP group was 4.1 ± 1.9 h. AHI decreased from baseline to end-of-study in both CPAP and UC groups (- 5.0 (- 12.5,2.0), P = 0.000; - 4.0 (- 12.5,1.5), P = 0.007, respectively), with no between-group difference (P = 0.453). An improvement in nadir SpO2 showed from baseline to end-of-study in the CPAP but not UC group (2.3% ± 6.1%, P = 0.011 and - 0.7% ± 7.6%, P = 0.511, respectively; between-group difference P = 0.032). Subgroup analysis shows that CPAP could improve AHI in patients with moderate OSA (- 8.0 (- 11.8, - 2.8) in CPAP group, - 2.0 (- 0.8,6.0) in UC group, P = 0.022) and improve nadir SpO2 in patients with severe OSA (5.0 (- 0.8, - 0.8,7.0) in CPAP group, 0.0 (- 8.5,2.5) in UC group, P = 0.032). CONCLUSION: Long-term CPAP use did not result in clinically significant changes in AHI or ODI overall but showed variable effects stratified by OSA severity. CLINICAL TRIAL REGISTRATION: Registry: Clinical Trials.gov, title: Continuous Positive Airway Pressure Treatment of Obstructive Sleep Apnea to Prevent Cardiovascular Disease (SAVE), URL: www. CLINICALTRIALS: gov , identifier: NCT00738179.


Asunto(s)
Enfermedades Cardiovasculares , Síndromes de la Apnea del Sueño , Apnea Obstructiva del Sueño , Adulto , Humanos , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/terapia , Presión de las Vías Aéreas Positiva Contínua/métodos , Apnea Obstructiva del Sueño/epidemiología , Apnea Obstructiva del Sueño/terapia , Comorbilidad
6.
Macromol Rapid Commun ; 43(16): e2200017, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35150177

RESUMEN

The photochemical reaction is a very important type of chemical reaction. Visualizing and controlling photo-mediated reactions is a long-standing goal and challenge. In this regard, single-molecule electrical detection with label-free, real-time, and in situ characteristics has unique advantages in monitoring the dynamic process of photoreactions at the single-molecule level. In this review, a valuable summary of the latest process of single-molecule photochemical reactions based on single-molecule electrical platforms is provided. The single-molecule electrical detection platforms for monitoring photoreactions are displayed, including their fundamental principles, construction methods, and practical applications. The single-molecule studies of two different types of light-mediated reactions are summarized as below: i) photo-induced reactions, including reversible cyclization, conformational isomerization, and other photo-related reactions; ii) plasmon-mediated photoreactions, including reaction mechanisms and concrete examples, such as plasmon-induced photolysis of SS/OO bonds and tautomerization of porphycene. In addition, the prospects for future research directions and challenges in this field are also discussed.


Asunto(s)
Nanotecnología , Fotólisis
7.
Sleep Breath ; 26(2): 595-604, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34185231

RESUMEN

PURPOSE: This study aims to assess changes in cardiac imageology of patients with mild obstructive sleep apnea (OSA) without cardiovascular disease. METHODS: All enrolled participants underwent polysomnography (PSG). Some participants underwent transthoracic echocardiography, speckle tracking echocardiography, and cardiac-enhanced magnetic resonance imaging (MRI) if they were willing. They were divided into three groups according to PSG results: non-OSA, mild OSA, and moderate-to-severe OSA. Imageology parameters were compared, and the relationship between OSA severity and imageology indices was analyzed by correlation analysis and multiple linear regression. RESULTS: Of the 352 enrolled participants, 274 participants with OSA had an apnea-hypopnea index (AHI) of ≥ 5 (86 mild OSA and 188 moderate-to-severe OSA cases), and 78 participants with non-OSA had an AHI of < 5. Transthoracic echocardiography showed that E/A and E'/A' values were lower in the mild OSA group than in the non-OSA group (1.12 ± 0.37 vs 1.27 ± 0.45 and 0.83 ± 0.33 vs 0.99 ± 0.42, respectively, p < 0.05). The aorta and ascending aorta widths were smaller in the mild OSA group than in the moderate-and-severe OSA groups (27.36 ± 2.87 mm vs 28.87 ± 2.95 mm and 30.27 ± 3.79 mm vs 31.63 ± 3.74 mm, respectively, p < 0.05). A regression analysis showed that cardiac function changes in patients with OSA may be related to age, obesity, and OSA severity. CONCLUSION: Patients with mild OSA without cardiovascular disease displayed changes in cardiac structure and function on transthoracic echocardiography.


Asunto(s)
Enfermedades Cardiovasculares , Apnea Obstructiva del Sueño , Enfermedades Cardiovasculares/diagnóstico por imagen , Ecocardiografía , Corazón , Humanos , Polisomnografía , Apnea Obstructiva del Sueño/diagnóstico por imagen
8.
Inorg Chem ; 60(9): 6503-6513, 2021 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-33847486

RESUMEN

Low-toxic InP quantum dots (QDs) as an ideal candidate for Cd-based QDs have tremendous potential for next-generation commercial display and biological detection applications. However, the progress in biological detection is still far behind that of the Cd-based QDs. This is mainly because the InP-based QDs are of inferior stability and photoluminescence quantum yield (PL QY) in aqueous solution. Here, PL QY of 65% and excellent stability of InP/GaP/ZnS QD@SiO2 nanoparticles have been successfully synthesized via a silica coating method. The containing thiol-capped hydrophobic InP/GaP/ZnS QDs were pre-silanized with waterless, ammonia-free hydrolysis tetraethyl orthosilicate, and subsequently, an outer silica shell was generated in the reverse microemulsion. The corresponding QD-based fluorescence-linked immunosorbent assay exhibits a high sensitivity of 0.9 ng mL-1 for C-reactive protein and the broad detection range of 1-1000 ng mL-1, which was close to that of the state-of-the-art Cd-based QD@SiO2 nanoparticles and had the highest sensitivity of Cd-free QDs so far. This work provides a very successful silica coating method for the containing thiol-capped hydrophobic QDs and the QDs highly sensitive to water and oxygen, and the obtained InP/GaP/ZnS QD@SiO2 nanoparticles were considered as the robust, biocompatible, and promising Cd-free fluorescent labels for the further ultra-sensitive detection.


Asunto(s)
Materiales Biocompatibles/química , Ensayo de Inmunoadsorción Enzimática , Técnica del Anticuerpo Fluorescente , Indio/química , Fosfinas/química , Puntos Cuánticos/química , Dióxido de Silicio/química , Tamaño de la Partícula
9.
Nanotechnology ; 32(48)2021 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-34371487

RESUMEN

The development trend ofin vitrodiagnostics is to obtain various biological information from a sample at extremely low concentration and volume, which has promoted its progress in accurate and sensitive multiplexed detection. Here, we developed a single color quantum dot (QD) based three-dimensional (3D) structure matrix microarray and conducted the detection of two inflammatory factors (C-reactive protein (CRP) and serum amyloid A (SAA)) by a self-built fluorescence detection system. This strategy increased detection sensitivity by immobilizing the antibody specifically on the 3D substrate because it captured more than about 7 times of 'effective' antibodies compared to the two-dimensional (2D) plane. Compared to the dual QDs-2D fluorescence-linked immunosorbent assay, the limit of detection (LOD) of 3D microarray based on QDs modified with amphiphilic polymers has been further improved to 0.11 ng ml-1for SAA assay and to 0.16 ng ml-1for CRP assay, respectively. By using QD microspheres (SiO2@QDs@SiO2-COOH, containing approximately 200-300 hydrophobic QDs on per SiO2sphere) as fluorescent labels, the LOD for CRP and SAA of 3D microarray reached as high as 15 pg ml-1and 86 pg ml-1, and the sensitivity was further improved by 28-fold and 425-fold, respectively. Because of its excellent performance, this QD microspheres-based 3D microarray has great application potential for highly sensitive and multiplexed quantitative detection of other biomarkers, small molecules, and antibiotic residues in biomedicine and food safety.


Asunto(s)
Análisis por Micromatrices/instrumentación , Microesferas , Puntos Cuánticos/química , Anticuerpos Inmovilizados/química , Biomarcadores/análisis , Proteína C-Reactiva/análisis , Inmunoensayo , Límite de Detección , Proteína Amiloide A Sérica/análisis , Dióxido de Silicio/química
10.
Biochem Genet ; 57(4): 555-570, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30734883

RESUMEN

Camellia sinensis (L.) O. Kuntze is one of the most important non-alcoholic beverage crops in Asian and African countries. In recent years, many green tea cultivars have been released and played an important role in improving the production and quality of tea trees. The objectives of this study were to assess the genetic diversity of the eighteen main green tea cultivars in Zhejiang Province-the most famous green tea-producing area of China-using start codon-targeted (SCoT) markers and to develop a specific sequence-characterized amplified region (SCAR) marker for application in cultivar diagnosis. Thirty-one SCoT primers produced 264 loci, 226 of which were polymorphic. The genetic similarity coefficients among these green tea cultivars ranged from 0.587 to 0.814, indicating that a high level of genetic diversity was present. Both a UPGMA dendrogram and a PCoA plot grouped the tea cultivars into three groups. The partitioning of groups in the UPGMA and PCoA was similar, and much of the clustering was highly consistent with the classification of tea cultivars according to their genetic backgrounds. A unique SCoT band, SCoT4-1649, specific to the tea cultivar 'Yingshuang,' was transformed into a SCAR marker. This SCAR marker is highly useful for the identification and germplasm conservation of green tea cultivars.


Asunto(s)
Camellia sinensis/genética , Secuencia de Bases , China , Codón Iniciador , Cartilla de ADN/genética , ADN de Plantas/genética , Marcadores Genéticos , Variación Genética , Fitomejoramiento , Reacción en Cadena de la Polimerasa , Té/genética
11.
Int J Mol Sci ; 20(11)2019 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-31181825

RESUMEN

WRKY transcription factors (TFs) containing one or two WRKY domains are a class of plant TFs that respond to diverse abiotic stresses and are associated with developmental processes. However, little has been known about the function of WRKY gene in tea plant. In this study, a subgroup IId WRKY gene CsWRKY7 was isolated from Camellia sinensis, which displayed amino acid sequence homology with Arabidopsis AtWRKY7 and AtWRKY15. Subcellular localization prediction indicated that CsWRKY7 localized to nucleus. Cis-acting elements detected in the promotor region of CsWRKY7 are mainly involved in plant response to environmental stress and growth. Consistently, expression analysis showed that CsWRKY7 transcripts responded to NaCl, mannitol, PEG, and diverse hormones treatments. Additionally, CsWRKY7 exhibited a higher accumulation both in old leaves and roots compared to bud. Seed germination and root growth assay indicated that overexpressed CsWRKY7 in transgenic Arabidopsis was not sensitive to NaCl, mannitol, PEG, and low concentration of ABA treatments. CsWRKY7 overexpressing Arabidopsis showed a late-flowering phenotype under normal conditions compared to wild type. Furthermore, gene expression analysis showed that the transcription levels of the flowering time integrator gene FLOWERING LOCUS T (FT) and the floral meristem identity genes APETALA1 (AP1) and LEAFY (LFY) were lower in WRKY7-OE than in the WT. Taken together, these findings indicate that CsWRKY7 TF may participate in plant growth. This study provides a potential strategy to breed late-blooming tea cultivar.


Asunto(s)
Arabidopsis/genética , Camellia sinensis/metabolismo , Plantas Modificadas Genéticamente/crecimiento & desarrollo , Factor de Transcripción TFIID/genética , Factor de Transcripción TFIID/metabolismo , Arabidopsis/crecimiento & desarrollo , Proteínas de Arabidopsis/genética , Camellia sinensis/genética , Núcleo Celular/metabolismo , Clonación Molecular , Regulación de la Expresión Génica de las Plantas , Hojas de la Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raíces de Plantas/metabolismo , Regiones Promotoras Genéticas , Homología de Secuencia de Aminoácido , Estrés Fisiológico , Factores de Transcripción/genética
12.
Plant Mol Biol ; 94(1-2): 97-107, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28321650

RESUMEN

KEY MESSAGE: This research is the first to demonstrate that OsSAUR45 is involved in plant growth though affecting auxin synthesis and transport by repressing OsYUCCA and OsPIN gene expression in rice. Small auxin-up RNAs (SAURs) comprise a large multigene family and are rapidly activated as part of the primary auxin response in plants. However, little is known about the role of SAURs in plant growth and development, especially in monocots. Here, we report the biological function of OsSAUR45 in the model plant rice (Oryza sativa). OsSAUR45 is expressed in a tissue-specific pattern and is localized to the cytoplasm. Rice lines overexpressing OsSAUR45 displayed pleiotropic developmental defects including reduced plant height and primary root length, fewer adventitious roots, narrower leaves, and reduced seed setting. Auxin levels and transport were reduced in the OsSAUR45 overexpression lines, potentially because of decreased expression of Flavin-binding monooxygenase family proteins (OsYUCCAs) and PIN-FORMED family proteins (OsPINs). Exogenous auxin application rapidly induced OsSAUR45 expression and partially restored the phenotype of rice lines overexpressing OsSAUR45. These results demonstrate that OsSAUR45 is involved in plant growth by affecting auxin synthesis and transport through the repression of OsYUCCA and OsPIN gene expression in rice.


Asunto(s)
Regulación de la Expresión Génica de las Plantas/fisiología , Ácidos Indolacéticos/metabolismo , Oryza/metabolismo , ARN de Planta/metabolismo , Transporte Biológico , Oryza/genética , Plantas Modificadas Genéticamente , ARN de Planta/genética
13.
Pestic Biochem Physiol ; 137: 81-90, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28364808

RESUMEN

Trehalase (TRE) is a key enzyme in trehalose degradation and has important functions in insect growth and chitin synthesis. Though validamycin has the potential for pest control by suppressing TRE activities, it is not known whether validamycin acts on both trehalose and chitin metabolism. TRE1 and TRE2 activities and glucose and glycogen contents decreased significantly after the injection of different doses of validamycin solution compared with the control group, while the trehalose content increased significantly. Overall, it showed that about 13 to 38% insects was appeared abnormal phenotypes, and 10 to 57% of insects died 48h after injection of solutions with different concentrations of validamycin; the chitin content also decreased significantly. Validamycin altered the relative expression levels of trehalose, glycogen and chitin metabolism-related genes by suppressing the activities of two TREs. We showed that the expression levels of three TRE and two trehalose-6-phosphate synthase (TPS) genes increased, while the expression levels of GP; CHS1 and its two transcripts, CHS1a, CHS1b; six chitinases, including Cht3, Cht4, Cht5, Cht6, Cht7, Cht9; and the HK, G6PI2, GFAT, GNPNA, PAGM1, UAP, VVL, CI and AP genes decreased significantly 48h after the injection of any validamycin concentration compared with the control group. These results demonstrate that by inhibiting the activities of two TREs, validamycin alters N. lugens chitin synthesis and degradation and affects trehalose and chitin metabolism-related gene expression. The development of TRE inhibitors may provide effective pest control in the future.


Asunto(s)
Quitina/biosíntesis , Hemípteros/metabolismo , Inositol/análogos & derivados , Insecticidas , Trehalasa/metabolismo , Trehalosa/metabolismo , Animales , China , Expresión Génica/efectos de los fármacos , Oryza/crecimiento & desarrollo , Trehalasa/genética
14.
BMC Plant Biol ; 16(1): 195, 2016 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-27609021

RESUMEN

BACKGROUND: The new shoots of the albino tea cultivar 'Anji Baicha' are yellow or white at low temperatures and turn green as the environmental temperatures increase during the early spring. 'Anji Baicha' metabolite profiles exhibit considerable variability over three color and developmental stages, especially regarding the carotenoid, chlorophyll, and theanine concentrations. Previous studies focused on physiological characteristics, gene expression differences, and variations in metabolite abundances in albino tea plant leaves at specific growth stages. However, the molecular mechanisms regulating metabolite biosynthesis in various color and developmental stages in albino tea leaves have not been fully characterized. RESULTS: We used RNA-sequencing to analyze 'Anji Baicha' leaves at the yellow-green, albescent, and re-greening stages. The leaf transcriptomes differed considerably among the three stages. Functional classifications based on Gene Ontology enrichment and Kyoto Encyclopedia of Genes and Genomes enrichment analyses revealed that differentially expressed unigenes were mainly related to metabolic pathways, biosynthesis of secondary metabolites, phenylpropanoid biosynthesis, and carbon fixation in photosynthetic organisms. Chemical analyses revealed higher ß-carotene and theanine levels, but lower chlorophyll a levels, in the albescent stage than in the green stage. Furthermore, unigenes involved in carotenoid, chlorophyll, and theanine biosyntheses were identified, and the expression patterns of the differentially expressed unigenes in these biosynthesis pathways were characterized. Through co-expression analyses, we identified the key genes in these pathways. These genes may be responsible for the metabolite biosynthesis differences among the different leaf color and developmental stages of 'Anji Baicha' tea plants. CONCLUSIONS: Our study presents the results of transcriptomic and biochemical analyses of 'Anji Baicha' tea plants at various stages. The distinct transcriptome profiles for each color and developmental stage enabled us to identify changes to biosynthesis pathways and revealed the contributions of such variations to the albino phenotype of tea plants. Furthermore, comparisons of the transcriptomes and related metabolites helped clarify the molecular regulatory mechanisms underlying the secondary metabolic pathways in different stages.


Asunto(s)
Camellia sinensis/genética , Carotenoides/genética , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Vías Biosintéticas , Camellia sinensis/crecimiento & desarrollo , Camellia sinensis/metabolismo , Carotenoides/biosíntesis , Clorofila/metabolismo , Perfilación de la Expresión Génica , Glutamatos/metabolismo , Hojas de la Planta/genética , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Proteínas de Plantas/metabolismo
15.
Physiol Plant ; 158(4): 435-451, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27282332

RESUMEN

Tea (Camellia sinensis) is a popular beverage worldwide. Drought stress (DS) is a major constraint on the growth, yield and quality of tea plants. MicroRNAs (miRNAs) play important roles in plant responses to DS. We constructed eight small RNA libraries from the drought-tolerant 'Ningzhou 2' (NZ2) and drought-susceptible 'Zhuyeqi' (ZYQ) cultivars during four stages [control (CK), the fourth day of DS, the eighth day of DS and after recovery (RC)]. A total of 268 conserved and 62 novel miRNAs were identified using small RNA sequencing. In total, 139 (52.9%) and 96 (36.0%) conserved miRNAs were differentially expressed during the four stages (P ≤ 0.05) in NZ2 and ZYQ, respectively. A total of 814 predicted target genes were identified as differentially regulated by 199 miRNAs through degradome sequencing. Among them, 201 and 218 genes were specific to the NZ2 and ZYQ cultivars, respectively, and 395 were common to both cultivars. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses revealed the biological roles of these targets and showed that some of the targets responded to DS in a stress- and cultivar-dependent manner. Correlated expression patterns between miRNA and their targets showed that specific miRNAs target the miRNA effector Argonaute 1 (AGO1), drought signaling-related receptors and enzymes, transcription factors, and other structural and functional proteins. The predicted regulatory networks provide insights into a potential miRNA-mediated regulatory mechanism. These results will contribute to the breeding of drought-tolerant tea plants and to elucidating miRNA regulation in response to drought.


Asunto(s)
Camellia sinensis/fisiología , MicroARNs/fisiología , ARN de Planta/fisiología , Camellia sinensis/genética , Deshidratación/metabolismo , Deshidratación/fisiopatología , Regulación de la Expresión Génica de las Plantas/genética , Regulación de la Expresión Génica de las Plantas/fisiología , MicroARNs/genética , ARN de Planta/genética , Análisis de Secuencia de ARN
16.
Plant J ; 78(4): 632-645, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24597623

RESUMEN

N-glycosylation is a major modification of glycoproteins in eukaryotic cells. In Arabidopsis, great progress has been made in functional analysis of N-glycan production, however there are few studies in monocotyledons. Here, we characterized a rice (Oryza sativa L.) osmogs mutant with shortened roots and isolated a gene that coded a putative mannosyl-oligosaccharide glucosidase (OsMOGS), an ortholog of α-glucosidase I in Arabidopsis, which trims the terminal glucosyl residue of the oligosaccharide chain of nascent peptides in the endoplasmic reticulum (ER). OsMOGS is strongly expressed in rapidly cell-dividing tissues and OsMOGS protein is localized in the ER. Mutation of OsMOGS entirely blocked N-glycan maturation and inhibited high-mannose N-glycan formation. The osmogs mutant exhibited severe defects in root cell division and elongation, resulting in a short-root phenotype. In addition, osmogs plants had impaired root hair formation and elongation, and reduced root epidemic cell wall thickness due to decreased cellulose synthesis. Further analysis showed that auxin content and polar transport in osmogs roots were reduced due to incomplete N-glycosylation of the B subfamily of ATP-binding cassette transporter proteins (ABCBs). Our results demonstrate that involvement of OsMOGS in N-glycan formation is required for auxin-mediated root development in rice.


Asunto(s)
Ácidos Indolacéticos/metabolismo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Raíces de Plantas/metabolismo , Polisacáridos/metabolismo , alfa-Glucosidasas/metabolismo , Transportadoras de Casetes de Unión a ATP/genética , Transportadoras de Casetes de Unión a ATP/metabolismo , Secuencia de Bases , Transporte Biológico , División Celular , Tamaño de la Célula , Pared Celular/genética , Pared Celular/metabolismo , Pared Celular/ultraestructura , Retículo Endoplásmico/metabolismo , Regulación del Desarrollo de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Glicosilación , Microscopía Confocal , Microscopía Electrónica , Datos de Secuencia Molecular , Mutación , Oryza/genética , Oryza/crecimiento & desarrollo , Filogenia , Epidermis de la Planta/citología , Epidermis de la Planta/genética , Epidermis de la Planta/metabolismo , Proteínas de Plantas/clasificación , Proteínas de Plantas/genética , Raíces de Plantas/genética , Raíces de Plantas/crecimiento & desarrollo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , alfa-Glucosidasas/clasificación , alfa-Glucosidasas/genética
17.
Plant J ; 79(1): 106-17, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24798203

RESUMEN

Members of the ATP Binding Cassette B/Multidrug-Resistance/P-glyco-protein (ABCB/MDR/PGP) subfamily were shown to function primarily in Oryza sativa (rice) auxin transport; however, none of the rice ABCB transporters have been functionally characterized. Here, we describe that a knock-down of OsABCB14 confers decreased auxin concentrations and polar auxin transport rates, conferring insensitivity to 2,4-dichlorophenoxyacetic acid (2,4-D) and indole-3-acetic acid (IAA). OsABCB14 displays enhanced specific auxin influx activity in yeast and protoplasts prepared from rice knock-down alleles. OsABCB14 is localized at the plasma membrane, pointing to an important directionality under physiological conditions. osabcb14 mutants were surprisingly found to be insensitive to iron deficiency treatment (-Fe). Their Fe concentration is higher and upregulation of Fe deficiency-responsive genes is lower in osabcb14 mutants than in wild-type rice (Nipponbare, NIP). Taken together, our results strongly support the role of OsABCB14 as an auxin influx transporter involved in Fe homeostasis. The functional characterization of OsABCB14 provides insights in monocot auxin transport and its relationship to Fe nutrition.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Ácidos Indolacéticos/metabolismo , Hierro/metabolismo , Proteínas de Transporte de Membrana/metabolismo , Oryza/genética , Reguladores del Crecimiento de las Plantas/metabolismo , Transporte Biológico , Genes Reporteros , Homeostasis , Proteínas de Transporte de Membrana/genética , Mutagénesis Insercional , Oryza/citología , Oryza/fisiología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raíces de Plantas/citología , Raíces de Plantas/genética , Raíces de Plantas/fisiología , Brotes de la Planta/citología , Brotes de la Planta/genética , Brotes de la Planta/fisiología , Plantas Modificadas Genéticamente , Protoplastos
18.
Plant Cell Environ ; 38(4): 638-54, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24995795

RESUMEN

Auxin and brassinosteroid (BR) are important phytohormones for controlling lamina inclination implicated in plant architecture and grain yield. But the molecular mechanism of auxin and BR crosstalk for regulating lamina inclination remains unknown. Auxin response factors (ARFs) control various aspects of plant growth and development. We here report that OsARF19-overexpression rice lines show an enlarged lamina inclination due to increase of its adaxial cell division. OsARF19 is expressed in various organs including lamina joint and strongly induced by auxin and BR. Chromatin immunoprecipitation (ChIP) and yeast one-hybrid assays demonstrate that OsARF19 binds to the promoter of OsGH3-5 and brassinosteroid insensitive 1 (OsBRI1) directing their expression. OsGH3-5-overexpression lines show a similar phenotype as OsARF19-O1. Free auxin contents in the lamina joint of OsGH3-5-O1 or OsARF19-O1 are reduced. OsGH3-5 is localized at the endoplasmic retieulum (ER) matching reduction of the free auxin contents in OsGH3-5-O1. osarf19-TDNA and osgh3-5-Tos17 mutants without erected leaves show a function redundancy with other members of their gene family. OsARF19-overexpression lines are sensitive to exogenous BR treatment and alter the expressions of genes related to BR signalling. These findings provide novel insights into auxin and BR signalling, and might have significant implications for improving plant architecture of monocot crops.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Ácidos Indolacéticos/metabolismo , Oryza/genética , Reguladores del Crecimiento de las Plantas/metabolismo , Hojas de la Planta/genética , Proteínas de Plantas/metabolismo , Secuencia de Bases , Expresión Génica , Genes Reporteros , Datos de Secuencia Molecular , Mutación , Oryza/anatomía & histología , Oryza/fisiología , Fenotipo , Hojas de la Planta/anatomía & histología , Hojas de la Planta/fisiología , Proteínas de Plantas/genética , Raíces de Plantas , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas/genética , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Plantones
19.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 35(7): 787-91, 2015 Jul.
Artículo en Zh | MEDLINE | ID: mdl-26380439

RESUMEN

OBJECTIVE: To explore the effect of Compound Tongtu Granule (CTG) on intestinal permeability in elderly sepsis patients. METHODS: Eighty elderly sepsis patients were randomly assigned to the experimental group and the control group by randomized double blinded method, 40 in each group. On the basis of conventional antiseptic treatment program, patients in the experimental group took CTG, while those in the control group took placebos. The dosage for CTG or placebos was 14.3 g each package, one package each time, twice daily for 14 successive days. Patients' abdominal symptoms and signs, levels of serum inflammatory factors (high-sensitivity C-reactive protein and procalcitonin), levels of plasma endotoxin, and the intestinal permeability (IP, represented by urinary lactulose/mannitol excretion rate) were compared between the two groups before and after treatment. RESULTS: After 14-day treatment, patients in the experimental group had improved abdominal symptoms, increased frequency of defecation, significantly decreased levels of plasma endotoxin and IP, when compared with the control group (P < 0.05). CONCLUSION: CTG could improve the intestinal barrier function in elderly sepsis patients.


Asunto(s)
Medicamentos Herbarios Chinos/farmacología , Mucosa Intestinal/metabolismo , Sepsis/tratamiento farmacológico , Anciano , Proteína C-Reactiva/metabolismo , Calcitonina/metabolismo , Péptido Relacionado con Gen de Calcitonina , Defecación , Medicamentos Herbarios Chinos/uso terapéutico , Endotoxinas/metabolismo , Humanos , Permeabilidad , Precursores de Proteínas/metabolismo , Sepsis/fisiopatología
20.
New Phytol ; 201(1): 91-103, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24111723

RESUMEN

Phosphorus (P) is crucial nutrient element for crop growth and development. However, the network pathway regulating homeostasis of phosphate (Pi) in crops has many molecular breeding unknowns. Here, we report that an auxin response factor, OsARF12, functions in Pi homeostasis. Measurement of element content, quantitative reverse transcription polymerase chain reaction analysis and acid phosphatases (APases) activity assay showed that the osarf12 mutant and osarf12/25 double mutant with P-intoxicated phenotypes had higher P concentrations, up-regulation of the Pi transporter encoding genes and increased APase activity under Pi-sufficient/-deficient (+Pi/-Pi, 0.32/0 mM NaH2 PO4) conditions. Transcript analysis revealed that Pi-responsive genes--Phosphate starvation (OsIPS)1 and OsIPS2, SYG1/Pho81/XPR1(OsSPX1), Sulfoquinovosyldiacylglycerol 2 (OsSQD2), R2R3 MYB transcription factor (OsMYB2P-1) and Transport Inhibitor Response1 (OsTIR1)--were more abundant in the osarf12 and osarf12/25 mutants under +Pi/-Pi conditions. Knockout of OsARF12 also influenced the transcript abundances of the OsPHR2 gene and its downstream components, such as OsMiR399j, OsPHO2, OsMiR827, OsSPX-MFS1 and OsSPX-MFS2. Results from -Pi/1-naphthylphthalamic acid (NPA) treatments, and auxin reporter DR5::GUS staining suggest that root system alteration and Pi-induced auxin response were at least partially controlled by OsARF12. These findings enrich our understanding of the biological functions of OsARF12, which also acts in regulating Pi homeostasis.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Ácidos Indolacéticos/metabolismo , Oryza/genética , Fosfatos/metabolismo , Fósforo/metabolismo , Factores de Transcripción/genética , Homeostasis , MicroARNs , Mutación , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raíces de Plantas/metabolismo , Plantas Modificadas Genéticamente , Factores de Transcripción/metabolismo , Activación Transcripcional
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