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1.
Plant Physiol ; 192(2): 1080-1098, 2023 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-36943245

RESUMEN

The functions of sucrose transporters (SUTs) differ among family members. The physiological function of SUT1 has been studied intensively, while that of SUT4 in various plant species including tomato (Solanum lycopersicum) is less well-understood. In this study, we characterized the function of tomato SlSUT4 in the regulation of flowering using a combination of molecular and physiological analyses. SlSUT4 displayed transport activity for sucrose when expressed in yeast (Saccharomyces cerevisiae), and it localized at both the plasma membrane and tonoplast. SlSUT4 interacted with SlSUT1, causing partial internalization of the latter, the main phloem loader of sucrose in tomato. Silencing of SlSUT4 promoted SlSUT1 localization to the plasma membrane, contributing to increased sucrose export and thus increased sucrose level in the shoot apex, which promoted flowering. Both silencing of SlSUT4 and spraying with sucrose suppressed gibberellin biosynthesis through repression of ent-kaurene oxidase and gibberellin 20-oxidase-1 (2 genes encoding key enzymes in gibberellin biosynthesis) expression by SlMYB76, which directly bound to their promoters. Silencing of SlMYB76 promoted gibberellin biosynthesis. Our results suggest that SlSUT4 is a functional SUT in tomato; downregulation of SlSUT4 expression enhances sucrose transport to the shoot apex, which promotes flowering by inhibiting gibberellin biosynthesis.


Asunto(s)
Solanum lycopersicum , Solanum lycopersicum/genética , Giberelinas , Sacarosa/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Regulación de la Expresión Génica de las Plantas
2.
Ophthalmic Res ; 67(1): 76-84, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38104543

RESUMEN

BACKGROUND: High altitude (HA) is an extremely challenging environment for millions of people who either travel to HA regions or inhabit there permanently. SUMMARY: Significant progress has been made over the past decades in the understanding of physiological adaptations in HA conditions, and recently, more studies regarding its influence on metabolic disease have been published. However, the effect of HA on diabetic retinopathy (DR), the leading cause of blindness, remains unclear. KEY MESSAGES: The present article provides an overview of the changes in the principal physiology and clinical characteristics related to DR after HA exposure. Despite conflicting evidence, this review synthesizes the available studies and explores the potential mechanisms, such as genetic adaptations, glucose homeostasis, and related physiological changes, by which long-term exposure to HA may alleviate the progression of DR. By shedding light on this complex relationship, it also provides insights into the interplay between HA and DR, offering valuable implications for clinical practice and further research.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Humanos , Altitud , Homeostasis
3.
Plant Biotechnol J ; 20(8): 1622-1635, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35524453

RESUMEN

Plant genetic transformation is a crucial step for applying biotechnology such as genome editing to basic and applied plant science research. Its success primarily relies on the efficiency of gene delivery into plant cells and the ability to regenerate transgenic plants. In this study, we have examined the effect of several developmental regulators (DRs), including PLETHORA (PLT5), WOUND INDUCED DEDIFFERENTIATION 1 (WIND1), ENHANCED SHOOT REGENERATION (ESR1), WUSHEL (WUS) and a fusion of WUS and BABY-BOOM (WUS-P2A-BBM), on in planta transformation through injection of Agrobacterium tumefaciens in snapdragons (Antirrhinum majus). The results showed that PLT5, WIND1 and WUS promoted in planta transformation of snapdragons. An additional test of these three DRs on tomato (Solanum lycopersicum) further demonstrated that the highest in planta transformation efficiency was observed from PLT5. PLT5 promoted calli formation and regeneration of transformed shoots at the wound positions of aerial stems, and the transgene was stably inherited to the next generation in snapdragons. Additionally, PLT5 significantly improved the shoot regeneration and transformation in two Brassica cabbage varieties (Brassica rapa) and promoted the formation of transgenic calli and somatic embryos in sweet pepper (Capsicum annum) through in vitro tissue culture. Despite some morphological alternations, viable seeds were produced from the transgenic Bok choy and snapdragons. Our results have demonstrated that manipulation of PLT5 could be an effective approach for improving in planta and in vitro transformation efficiency, and such a transformation system could be used to facilitate the application of genome editing or other plant biotechnology application in modern agriculture.


Asunto(s)
Brassica , Capsicum , Solanum lycopersicum , Agrobacterium tumefaciens/genética , Brassica/genética , Capsicum/genética , Solanum lycopersicum/genética , Plantas Modificadas Genéticamente/genética , Transformación Genética , Transgenes
4.
Int Ophthalmol ; 42(6): 1927-1938, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35147832

RESUMEN

PURPOSE: To explore the profile of gut microbiota and central carbon-related metabolites in patients with primary angle-closure glaucoma (PACG). METHODS: The fecal microbiotas of 30 PACG patients and 30 healthy participants were detected via 16S rRNA sequencing. Targeted liquid chromatography-mass spectrometry was used to examine serum central carbon-related metabolites. The correlations among metabolites, microbiotas and clinical presentations were also explored. RESULTS: Although the α and ß diversity between the PACG and control groups did not show a significant difference, the distribution of Blautia and Fusicatenibacter decreased significantly in the PACG group. Functional annotations of microbiota enrichment showed that the most dominant pathway was related to host metabolism. In the PACG patients, seven central carbon metabolites, namely adenosine 5'-diphosphate, dGDP, phosphoenolpyruvic acid, d-ribulose 5-phosphate, d-xylulose 5-phosphate, glucuronic acid, and malonic acid, decreased significantly, whereas two metabolites, citric acid and isocitrate, increased obviously. The mean RNFL thickness was positively correlated with phosphoenolpyruvic acid, the VF-MD was positively correlated with glucuronic acid, and the abundance of Blautia was negatively associated with citric acid. CONCLUSION: Few species of gut microbiota were altered in the PACG patients compared to the healthy subjects. A distinct difference in the phenotype of the central carbon-related metabolites of PACG and their correlation with clinical presentations and microbiota suggests potential mechanisms of RGC impairment and novel intervention targets.


Asunto(s)
Microbioma Gastrointestinal , Glaucoma de Ángulo Cerrado , Glaucoma de Ángulo Abierto , Carbono , Ácido Cítrico , Ácido Glucurónico , Humanos , Presión Intraocular , ARN Ribosómico 16S/genética
5.
Int J Mol Sci ; 22(9)2021 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-33946733

RESUMEN

Sucrose phosphate synthase (SPS), sucrose synthase (SUS) and invertase (INV) are all encoded by multigene families. In tomato (Solanum lycopersicum), a comprehensive analysis of structure characteristics of these family genes is still lacking, and the functions of individual isoforms of these families are mostly unclear under stress. Here, the structure characteristics of the three families in tomato were analyzed; moreover, as a first step toward understanding the functions of isoforms of these proteins under stress, the tissue expression pattern and stress response of these genes were also investigated. The results showed that four SPS genes, six SUS genes and nineteen INV genes were identified in tomato. The subfamily differentiation of SlSPS and SlSUS might have completed before the split of monocotyledons and dicotyledons. The conserved motifs were mostly consistent within each protein family/subfamily. These genes demonstrated differential expressions among family members and tissues, and in response to polyethylene glycerol, NaCl, H2O2, abscisic acid or salicylic acid treatment. Our results suggest that each isoform of these families may have different functions in different tissues and under environmental stimuli. SlSPS1, SlSPS3, SlSUS1, SlSUS3, SlSUS4, SlINVAN5 and SlINVAN7 demonstrated consistent expression responses and may be the major genes responding to exogenous stimuli.


Asunto(s)
Genes de Plantas , Glucosiltransferasas/genética , Proteínas de Plantas/genética , Solanum lycopersicum/enzimología , Solanum lycopersicum/genética , beta-Fructofuranosidasa/genética , Mapeo Cromosómico , Cromosomas de las Plantas/genética , Evolución Molecular , Regulación Enzimológica de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Genoma de Planta , Familia de Multigenes , Filogenia , Estrés Fisiológico/genética , Sintenía
6.
Plant Physiol ; 179(2): 616-629, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30498025

RESUMEN

Cation/H+ (NHX-type) antiporters are important regulators of intracellular ion homeostasis and are critical for cell expansion and plant stress acclimation. In Arabidopsis (Arabidopsis thaliana), four distinct NHX isoforms, named AtNHX1 to AtNHX4, locate to the tonoplast. To determine the concerted roles of all tonoplast NHXs on vacuolar ion and pH homeostasis, we examined multiple knockout mutants lacking all but one of the four vacuolar isoforms and quadruple knockout plants lacking any vacuolar NHX activity. The nhx triple and quadruple knockouts displayed reduced growth phenotypes. Exposure to sodium chloride improved growth while potassium chloride was deleterious to some knockouts. Kinetic analysis of K+ and Na+ transport indicated that AtNHX1 and AtNHX2 are the main contributors to both vacuolar pH and K+ and Na+ uptake, while AtNHX3 and AtNHX4 differ in Na+/K+ selectivity. The lack of any vacuolar NHX activity resulted in no K+ uptake, highly acidic vacuoles, and reduced but not abolished vacuolar Na+ uptake. Additional K+/H+ and Na+/H+ exchange activity assays in the quadruple knockout indicated Na+ uptake that was not H+ coupled, suggesting the existence of an alternative, cation/H+-independent, Na+ conductive pathway in vacuoles. These results highlight the importance of NHX-type cation/H+ antiporters in the maintenance of cellular cation homeostasis and in growth and development.


Asunto(s)
Antiportadores/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiología , Proteínas de Transporte de Catión/metabolismo , Intercambiadores de Sodio-Hidrógeno/metabolismo , Vacuolas/metabolismo , Antiportadores/genética , Arabidopsis/efectos de los fármacos , Proteínas de Arabidopsis/genética , Proteínas de Transporte de Catión/genética , Cationes Monovalentes , Etiolado/genética , Técnicas de Inactivación de Genes , Concentración de Iones de Hidrógeno , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Plantas Modificadas Genéticamente , Potasio/metabolismo , Potasio/farmacología , Sodio/metabolismo , Sodio/farmacología , Intercambiadores de Sodio-Hidrógeno/genética
7.
Plant Cell Environ ; 43(3): 732-744, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31724184

RESUMEN

Silicon (Si) accumulation in shoots differs greatly with plant species, but the molecular mechanisms for this interspecific difference are unknown. Here, we isolated homologous genes of rice Si influx (SlLsi1) and efflux (SlLsi2) transporter genes in tomato (Solanum lycopersicum L.) and functionally characterized these genes. SlLsi1 showed transport activity for Si when expressed in both rice lsi1 mutant and Xenopus laevis oocytes. SlLsi1 was constitutively expressed in the roots. Immunostaining showed that SlLsi1 was localized at the plasma membrane of both root tip and basal region without polarity. Furthermore, overexpression of SlLsi1 in tomato increased Si concentration in the roots and root cell sap but did not alter the Si concentration in the shoots. By contrast, two Lsi2-like proteins did not show efflux transport activity for Si in Xenopus oocytes. However, when functional CsLsi2 from cucumber was expressed in tomato, the Si uptake was significantly increased, resulting in higher Si accumulation in the leaves and enhanced tolerance of the leaves to water deficit and high temperature. Our results suggest that the low Si accumulation in tomato is attributed to the lack of functional Si efflux transporter Lsi2 required for active Si uptake although SlLsi1 is functional.


Asunto(s)
Proteínas de Transporte de Membrana/metabolismo , Proteínas de Plantas/metabolismo , Raíces de Plantas/metabolismo , Silicio/metabolismo , Solanum lycopersicum/metabolismo , Adaptación Fisiológica , Clonación Molecular , Deshidratación , Electrólitos/metabolismo , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Prueba de Complementación Genética , Respuesta al Choque Térmico , Solanum lycopersicum/genética , Proteínas de Transporte de Membrana/genética , Mutación/genética , Oryza/genética , Proteínas de Plantas/genética , Raíces de Plantas/genética , Plantas Modificadas Genéticamente , Transporte de Proteínas , Fracciones Subcelulares/metabolismo
8.
Exp Eye Res ; 191: 107921, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31917963

RESUMEN

The gut microbiota (GM) and its influence on host metabolism are considered to be an environmental factor that contributes to the progression of many immune and neurodegenerative diseases. However, the features of the GM and serum metabolites in Primary open-angle glaucoma (POAG) patients have not been clearly elucidated. The purpose of this research is to explore the gut microbial composition and serum metabolic phenotype in POAG patients. 16S rRNA V4 genes of bacteria from the fecal samples of 30 POAG patients and 30 healthy subjects were sequenced by the Illumina MiSeq platform and then analyzed by QIIME. Their serum samples were analyzed by gas chromatography/mass spectrometry (GC-MS)-based metabolomics. The association between gut microbial species and host circulating metabolites and clinical phenotypes was also analyzed. Compared with controls, f Prevotellaceae, g unidentified Enterobacteriaceae, and s Escherichia coli increased the most in POAG patients, whereas g Megamonas and s Bacteroides plebeius significantly decreased in POAG patients. The alteration of the endogenous metabolomic profile in POAG patients included five amino acids or dipeptides, two hormone derivates, one purine derivative, one bile acid derivative and one organic acid. It also showed that citric acid was positively correlated with Megamonas, whereas L-γ-Glutamyl-L-alanine, MHPG, cholic acid glucuronide and hypoxanthine were negatively correlated with Megamonas. Mean visual acuity was negatively correlated with Blautia, mean VF-MD was negatively correlated with Faecalibacterium, and average RNFL thickness was positively correlated with Streptococcus. Our results revealed that there was a distinct difference in GM composition and serum metabolic phenotype between POAG patients and healthy individuals. This finding suggests the potential correlations between the GM and serum metabolites in the pathogenesis of glaucoma and thus provides new insight into the GM-targeted interventions of this disease.


Asunto(s)
Microbioma Gastrointestinal/fisiología , Tracto Gastrointestinal/microbiología , Glaucoma de Ángulo Abierto/sangre , Metaboloma/fisiología , Anciano , Bacterias/genética , Bacterias/aislamiento & purificación , Heces/microbiología , Femenino , Cromatografía de Gases y Espectrometría de Masas , Voluntarios Sanos , Humanos , Masculino , Metabolómica/métodos , Persona de Mediana Edad , Fenotipo , ARN Ribosómico 16S/genética
9.
BMC Plant Biol ; 19(1): 345, 2019 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-31390991

RESUMEN

BACKGROUND: Aquaporin (AQP) proteins comprise a group of membrane intrinsic proteins (MIPs) that are responsible for transporting water and other small molecules, which is crucial for plant survival under stress conditions including salt stress. Despite the vital role of AQPs, little is known about them in cucumber (Cucumis sativus L.). RESULTS: In this study, we identified 39 aquaporin-encoding genes in cucumber that were separated by phylogenetic analysis into five sub-families (PIP, TIP, NIP, SIP, and XIP). Their substrate specificity was then assessed based on key amino acid residues such as the aromatic/Arginine (ar/R) selectivity filter, Froger's positions, and specificity-determining positions. The putative cis-regulatory motifs available in the promoter region of each AQP gene were analyzed and results revealed that their promoter regions contain many abiotic related cis-regulatory elements. Furthermore, analysis of previously released RNA-seq data revealed tissue- and treatment-specific expression patterns of cucumber AQP genes (CsAQPs). Three aquaporins (CsTIP1;1, CsPIP2;4, and CsPIP1;2) were the most transcript abundance genes, with CsTIP1;1 showing the highest expression levels among all aquaporins. Subcellular localization analysis in Nicotiana benthamiana epidermal cells revealed the diverse and broad array of sub-cellular localizations of CsAQPs. We then performed RNA-seq to identify the expression pattern of CsAQPs under salt stress and found a general decreased expression level of root CsAQPs. Moreover, qRT-PCR revealed rapid changes in the expression levels of CsAQPs in response to diverse abiotic stresses including salt, polyethylene glycol (PEG)-6000, heat, and chilling stresses. Additionally, transient expression of AQPs in N. benthamiana increased leaf water loss rate, suggesting their potential roles in the regulation of plant water status under stress conditions. CONCLUSIONS: Our results indicated that CsAQPs play important roles in response to salt stress. The genome-wide identification and primary function characterization of cucumber aquaporins provides insight to elucidate the complexity of the AQP gene family and their biological functions in cucumber.


Asunto(s)
Acuaporinas/fisiología , Cucumis sativus/genética , Proteínas de Plantas/fisiología , Acuaporinas/genética , Acuaporinas/metabolismo , Cucumis sativus/metabolismo , Expresión Génica , Regulación de la Expresión Génica de las Plantas , Genoma de Planta , Peróxido de Hidrógeno/metabolismo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estrés Fisiológico/genética , Transcriptoma , Agua/metabolismo
10.
Bioinformatics ; 34(13): i422-i428, 2018 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-29950021

RESUMEN

Motivation: Reprogramming somatic cells into neurons holds great promise to model neuronal development and disease. The efficiency and success rate of neuronal reprogramming, however, may vary between different conversion platforms and cell types, thereby necessitating an unbiased, systematic approach to estimate neuronal identity of converted cells. Recent studies have demonstrated that long genes (>100 kb from transcription start to end) are highly enriched in neurons, which provides an opportunity to identify neurons based on the expression of these long genes. Results: We have developed a versatile R package, LONGO, to analyze gene expression based on gene length. We propose a systematic analysis of long gene expression (LGE) with a metric termed the long gene quotient (LQ) that quantifies LGE in RNA-seq or microarray data to validate neuronal identity at the single-cell and population levels. This unique feature of neurons provides an opportunity to utilize measurements of LGE in transcriptome data to quickly and easily distinguish neurons from non-neuronal cells. By combining this conceptual advancement and statistical tool in a user-friendly and interactive software package, we intend to encourage and simplify further investigation into LGE, particularly as it applies to validating and improving neuronal differentiation and reprogramming methodologies. Availability and implementation: LONGO is freely available for download at https://github.com/biohpc/longo. Supplementary information: Supplementary data are available at Bioinformatics online.


Asunto(s)
Reprogramación Celular , Perfilación de la Expresión Génica/métodos , Neuronas/metabolismo , Programas Informáticos , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neuronas/fisiología , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Análisis de Secuencia de ARN/métodos , Transcriptoma
11.
Doc Ophthalmol ; 138(2): 137-145, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30739234

RESUMEN

OBJECTIVE: To assess the role of multifocal electroretinograms (mfERGs) and optical coherence tomography (OCT) for detecting early changes in macular functions of patients with nasopharyngeal carcinoma (NPC) after radiotherapy. METHODS: mfERGs and OCT were used to examine a NPC group (36 NPC patients after radiotherapy without clinically visible radiation retinopathy, 36 eyes) and a normal control group (25 healthy individuals, 25 eyes) with the same procedure and parameters. The two groups of mfERG were summarized by calculating ring averages, response density, N1 amplitude and P1 and N1 latencies were analysed. OCT scan thickness was summarized into ETDRS regions for comparison. RESULTS: Compared with controls, the NPC group had significantly decreased P1 response densities in 1-4 ring regions and N1 amplitudes in 1-3 rings (P < 0.01). P1 latencies were obviously prolonged in rings 1 (P < 0.01). In four quadrants (inferonasal, superonasal, inferotemporal and superotemporal) of the mfERG response waveforms, the NPC group had significantly decreased P1 response densities and N1 amplitudes mainly in the inferonasal and inferotemporal quadrants, showing statistically significant differences from the control group (P < 0.0125). But for the OCT results, there is no statistically significant difference between the NPC group and the control group. CONCLUSIONS: In NPC patients after radiotherapy, there may be changes in the mfERGs before any visible fundus lesions appeared as radiation macular oedema. Since the global OCT macular thickness analysis cannot reveal early changes, the mfERGs can objectively and quantitatively assess the earlier changes in macular function in NPC patients.


Asunto(s)
Electrorretinografía/métodos , Carcinoma Nasofaríngeo/radioterapia , Traumatismos por Radiación/fisiopatología , Radioterapia/efectos adversos , Retina/efectos de la radiación , Adulto , Anciano , Femenino , Fondo de Ojo , Humanos , Edema Macular/fisiopatología , Masculino , Persona de Mediana Edad , Retina/diagnóstico por imagen , Retina/fisiopatología , Tomografía de Coherencia Óptica/métodos , Agudeza Visual/fisiología
12.
Ecotoxicol Environ Saf ; 174: 245-254, 2019 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-30831473

RESUMEN

Salinity decreases the yield and quality of crops. Silicon (Si) has been widely reported to have beneficial effects on plant growth and development under salt stress. However, the mechanism is still poorly understood. In an attempt to identify genes or gene networks that may be orchestrated to improve salt tolerance of cucumber plants, we sequenced the transcriptomes of both control and salt-stressed cucumber leaves in the presence or absence of added Si. Seedlings of cucumber 'JinYou 1' were subjected to salt stress (75 mM NaCl) without or with addition of 0.3 mM Si. Plant growth, photosynthetic gas exchange and transcriptomic dynamics were investigated. The results showed that Si addition improved the growth and photosynthetic performance of cucumber seedlings under salt stress. The comparative transcriptome analysis revealed that Si played an important role in shaping the transcriptome of cucumber: the expressions of 1469 genes were altered in response to Si treatment in the control conditions, and these genes were mainly involved in ion transport, hormone and signal transduction, biosynthetic and metabolic processes, and stress and defense responses. Under salt stress alone, 1482 genes with putative functions associated with metabolic processes and responses to environmental stimuli have changed their expression levels. Si treatment shifted the transcriptome of salt-stressed cucumber back to that of the control, as evidenced that among the 708 and 774 genes that were up- or down-regulated under salt stress, a large majority of them (609 and 595, respectively) were reverted to the normal expression levels. These results suggest that Si may act as an elicitor to precondition cucumber plants and induce salt tolerance. The study may help us understand the mechanism for silicon-mediated salt tolerance and provide a theoretical basis for silicon application in crop production in saline soils.


Asunto(s)
Cucumis sativus/efectos de los fármacos , Estrés Salino/efectos de los fármacos , Silicatos/farmacología , Transcriptoma/efectos de los fármacos , Cucumis sativus/genética , Cucumis sativus/crecimiento & desarrollo , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Modelos Teóricos , Fotosíntesis/efectos de los fármacos , Fotosíntesis/genética , Desarrollo de la Planta/efectos de los fármacos , Desarrollo de la Planta/genética , Salinidad , Estrés Salino/genética , Tolerancia a la Sal/efectos de los fármacos , Tolerancia a la Sal/genética , Cloruro de Sodio/administración & dosificación
13.
Ecotoxicol Environ Saf ; 169: 8-17, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30412897

RESUMEN

Silicon can increase salt tolerance, but the underlying mechanism has remained unclear. Here, we investigated the effect of silicon on polyamine metabolism and the role of polyamine accumulation in silicon-mediated salt tolerance in cucumber. Seedlings of cucumber 'JinYou 1' were subjected to salt stress (75 mM NaCl) in the presence or absence of added 0.3 mM silicon. Plant growth, polyamine metabolism and effects of exogenous polyamines and polyamine synthesis inhibitor dicyclohexylammonium sulphate on oxidative damage were investigated. The results showed that salt stress inhibited plant growth and decreased leaf chlorophyll levels and the maximum quantum yield of PSII, and added silicon ameliorated these negative effects. Salt stress increased polyamine accumulation in the leaves and roots. Compared with salt stress alone, overall, silicon addition decreased free putrescine concentrations, but increased spermidine and spermine concentrations in both leaves and roots under salt stress. Silicon application resulted in increased polyamine levels under salt stress by promoting the activities of S-adenosylmethionine decarboxylase and arginine decarboxylase while inhibiting the activity of diamine oxidase. Exogenous application of spermidine and spermine alleviated salt-stress-induced oxidative damage, whereas polyamine synthesis inhibitor eliminated the silicon-mediated decrease in oxidative damage. The results suggest that silicon-enhanced polyamine accumulation in cucumber under salt stress may play a role in decreasing oxidative damage and therefore increase the salt tolerance.


Asunto(s)
Cucumis sativus/efectos de los fármacos , Poliaminas/metabolismo , Plantas Tolerantes a la Sal/efectos de los fármacos , Silicio/farmacología , Clorofila/metabolismo , Cucumis sativus/crecimiento & desarrollo , Cucumis sativus/metabolismo , Estrés Oxidativo/efectos de los fármacos , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/metabolismo , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/metabolismo , Putrescina/metabolismo , Tolerancia a la Sal , Plantas Tolerantes a la Sal/crecimiento & desarrollo , Plantas Tolerantes a la Sal/metabolismo , Espermidina/metabolismo , Espermina/metabolismo
14.
Ann Bot ; 122(4): 641-648, 2018 09 24.
Artículo en Inglés | MEDLINE | ID: mdl-29905780

RESUMEN

Background and Aims: Silicon has been proven to exert beneficial effects on plant growth and stress tolerance, and silicon accumulation varies among different plant species. Cucumber (Cucumis sativus) is a widely used dicot model for silicon accumulation, but little is known about the molecular mechanism of its silicon uptake. Previously, we isolated and characterized CsLsi1, a silicon influx transporter gene from cucumber. In this study, we cloned a putative silicon efflux transporter gene, CsLsi2, from cucumber and investigated its role in silicon uptake. Methods: The expression pattern, transport activity, and subcellular and cellular localizations of CsLsi2 were investigated. The transport activity of CsLsi2 was determined in Xenopus laevis oocytes. The subcelluar and cellular localizations were conducted by transient expression of fused 35S::CsLsi2-eGFP in onion epidermal cells and expression of ProCsLsi2::CsLsi2-mGFP in cucumber, respectively. Key Results: CsLsi2 was mainly expressed in the roots. Expression of CsLsi2-eGFP fusion sequence in onion epidermis cells showed that CsLsi2 was localized at the plasma membrane. Transient expression in Xenopus laevis oocytes showed that CsLsi2 demonstrated efflux but no influx transport activity for silicon, and the transport was energy-dependent. Expression of CsLsi2-mGFP under its own promoter revealed that CsLsi2 was mainly expressed on endodermal cells, showing no polar distribution. In combination with our previous work on CsLsi1, a model for silicon uptake in cucumber roots is proposed. Conclusion: The results suggest that CsLsi2 is a silicon efflux transporter gene in cucumber. The coordination of CsLsi1 and CsLsi2 mediates silicon uptake in cucumber roots. This study may help us understand the molecular mechanism for silicon uptake in cucumber, one of the few dicots with a relatively high capacity for silicon accumulation.


Asunto(s)
Cucumis sativus/genética , Proteínas de Transporte de Membrana/metabolismo , Silicio/metabolismo , Transporte Biológico , Membrana Celular/metabolismo , Cucumis sativus/fisiología , Genes Reporteros , Proteínas de Transporte de Membrana/genética , Especificidad de Órganos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estrés Fisiológico
15.
Physiol Plant ; 159(2): 201-214, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27701737

RESUMEN

Cucumber (Cucumis sativus) is a widely grown cucurbitaceous vegetable that exhibits a relatively high capacity for silicon (Si) accumulation, but the molecular mechanism for silicon uptake remains to be clarified. Here we isolated and characterized CsLsi1, a gene encoding a silicon transporter in cucumber (cv. Mch-4). CsLsi1 shares 55.70 and 90.63% homology with the Lsi1s of a monocot and dicot, rice (Oryza sativa) and pumpkin (Cucurbita moschata), respectively. CsLsi1 was predominantly expressed in the roots, and application of exogenous silicon suppressed its expression. Transient expression in cucumber protoplasts showed that CsLsi1 was localized in the plasma membrane. Heterologous expression in Xenopus laevis oocytes showed that CsLsi1 evidenced influx transport activity for silicon but not urea or glycerol. Expression of cucumber CsLsi1-mGFP under its own promoter showed that CsLsi1 was localized at the distal side of the endodermis and the cortical cells in the root tips as well as in the root hairs near the root tips. Heterologous expression of CsLsi1 in a rice mutant defective in silicon uptake and the over-expression of this gene in cucumber further confirmed the role of CsLsi1 in silicon uptake. Our results suggest that CsLsi1 is a silicon influx transporter in cucumber. The cellular localization of CsLsi1 in cucumber roots is different from that in other plants, implying the possible effect of transporter localization on silicon uptake capability.


Asunto(s)
Cucumis sativus/genética , Proteínas de Transporte de Membrana/metabolismo , Silicio/metabolismo , Secuencia de Aminoácidos , Transporte Biológico , Membrana Celular/metabolismo , Clorofila/metabolismo , Cucumis sativus/citología , Cucumis sativus/metabolismo , Flores/citología , Flores/genética , Flores/metabolismo , Genes Reporteros , Proteínas de Transporte de Membrana/genética , Mutación , Especificidad de Órganos , Oryza/citología , Oryza/genética , Oryza/metabolismo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raíces de Plantas/citología , Raíces de Plantas/genética , Tallos de la Planta/citología , Tallos de la Planta/genética , Tallos de la Planta/metabolismo , Plantones/citología , Plantones/genética , Plantones/metabolismo , Alineación de Secuencia
16.
BMC Ophthalmol ; 16: 106, 2016 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-27406120

RESUMEN

BACKGROUND: The ocular presentation of Castleman's disease (CD)-associated paraneoplastic pemphigus (PNP) has rarely been reported. In this report, we describe a young patient with CD-associated PNP who had recurrent corneal ulceration in addition to cicatrizing conjunctivitis. CASE PRESENTATION: We describe a case of 23-year-old male with mucocutaneous erosion and conjunctival injection and erosion who was found to have PNP. Pelvic hyaline-vascular CD was detected and completely excised. The mucocutaneous lesions improved postoperatively. Two years after pelvic surgery, the patient gradually developed conjunctival symblepharon in both eyes and pterygium in the right eye. The patient then underwent a successful exclusion of the symblepharon, an excision of the pterygium and an amniotic membrane transplantation in the right eye. However, after 6 months, he experienced an aseptic corneal ulcer and recurrent pterygiumin the right eye. After treatment with systemic and local immunosuppressive medications, the corneal ulcer gradually healed and remained stable. CONCLUSION: Corneal ulceration and melting, in addition to conjunctivitis, as a complication of CD-associated PNP, can be successfully managed with systemic and local immunosuppressants.


Asunto(s)
Enfermedad de Castleman/complicaciones , Úlcera de la Córnea/etiología , Síndromes Paraneoplásicos/complicaciones , Pénfigo/complicaciones , Conjuntivitis/etiología , Humanos , Masculino , Pterigion/etiología , Adulto Joven
17.
BMC Bioinformatics ; 16 Suppl 7: S7, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25952938

RESUMEN

BACKGROUND: The reconstruction of gene regulatory network from time course microarray data can help us comprehensively understand the biological system and discover the pathogenesis of cancer and other diseases. But how to correctly and efficiently decifer the gene regulatory network from high-throughput gene expression data is a big challenge due to the relatively small amount of observations and curse of dimensionality. Computational biologists have developed many statistical inference and machine learning algorithms to analyze the microarray data. In the previous studies, the correctness of an inferred regulatory network is manually checked through comparing with public database or an existing model. RESULTS: In this work, we present a novel procedure to automatically infer and verify gene regulatory networks from time series expression data. The dynamic Bayesian network, a statistical inference algorithm, is at first implemented to infer an optimal network from time series microarray data of S. cerevisiae, then, a weighted symbolic model checker is applied to automatically verify or falsify the inferred network through checking some desired temporal logic formulas abstracted from experiments or public database. CONCLUSIONS: Our studies show that the marriage of statistical inference algorithm with model checking technique provides a more efficient way to automatically infer and verify the gene regulatory network from time series expression data than previous studies.


Asunto(s)
Algoritmos , Biología Computacional/métodos , Interpretación Estadística de Datos , Perfilación de la Expresión Génica , Regulación Fúngica de la Expresión Génica/genética , Redes Reguladoras de Genes , Saccharomyces cerevisiae/genética , Genoma Fúngico , Humanos , Análisis de Secuencia por Matrices de Oligonucleótidos , Programas Informáticos , Factores de Tiempo
18.
Plant Cell Rep ; 34(9): 1629-46, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26021845

RESUMEN

KEY MESSAGE: Silicon enhances root water uptake in salt-stressed cucumber plants through up-regulating aquaporin gene expression. Osmotic adjustment is a genotype-dependent mechanism for silicon-enhanced water uptake in plants. Silicon can alleviate salt stress in plants. However, the mechanism is still not fully understood, and the possible role of silicon in alleviating salt-induced osmotic stress and the underlying mechanism still remain to be investigated. In this study, the effects of silicon (0.3 mM) on Na accumulation, water uptake, and transport were investigated in two cucumber (Cucumis sativus L.) cultivars ('JinYou 1' and 'JinChun 5') under salt stress (75 mM NaCl). Salt stress inhibited the plant growth and photosynthesis and decreased leaf transpiration and water content, while added silicon ameliorated these negative effects. Silicon addition only slightly decreased the shoot Na levels per dry weight in 'JinYou 1' but not in 'JinChun 5' after 10 days of stress. Silicon addition reduced stress-induced decreases in root hydraulic conductivity and/or leaf-specific conductivity. Expressions of main plasma membrane aquaporin genes in roots were increased by added silicon, and the involvement of aquaporins in water uptake was supported by application of aquaporin inhibitor and restorative. Besides, silicon application decreased the root xylem osmotic potential and increased root soluble sugar levels in 'JinYou 1.' Our results suggest that silicon can improve salt tolerance of cucumber plants through enhancing root water uptake, and silicon-mediated up-regulation of aquaporin gene expression may in part contribute to the increase in water uptake. In addition, osmotic adjustment may be a genotype-dependent mechanism for silicon-enhanced water uptake in plants.


Asunto(s)
Cucumis sativus/fisiología , Raíces de Plantas/metabolismo , Tolerancia a la Sal/efectos de los fármacos , Silicio/farmacología , Agua/metabolismo , Acuaporinas/genética , Acuaporinas/metabolismo , Transporte Biológico , Biomasa , Carbohidratos/análisis , Cucumis sativus/efectos de los fármacos , Cucumis sativus/genética , Cucumis sativus/crecimiento & desarrollo , Ditiotreitol/farmacología , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Genes de Plantas , Cloruro de Mercurio/farmacología , Ósmosis/efectos de los fármacos , Fotosíntesis/efectos de los fármacos , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/genética , Estomas de Plantas/efectos de los fármacos , Estomas de Plantas/fisiología , Transpiración de Plantas/efectos de los fármacos , Carácter Cuantitativo Heredable , Tolerancia a la Sal/genética , Plantones/efectos de los fármacos , Plantones/fisiología , Sodio/metabolismo , Solubilidad , Xilema/efectos de los fármacos , Xilema/fisiología
19.
Eur J Ophthalmol ; : 11206721241236918, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38425295

RESUMEN

PURPOSE: To analyze posttraumatic glaucoma regarding its demographics, presentations, different causes, surgical modalities, and hospitalization burden among patients in southern China. METHODS: This retrospective study investigated all individuals with posttraumatic glaucoma admitted to the Zhongshan Ophthalmic Center of Sun Yat-Sen University from January 2012 through December 2021. RESULTS: Out of 2211 cases, 64.82% had closed globe injury (CGI), 28.22% had open globe injury (OGI), and 6.96% had chemical injury (CI). The mean age of all patients was 44.45 ± 19.45 years old. Males (83.36%), rural patients (56.17%), and farmers (27.14%) predominantly had posttraumatic glaucoma. The most common external injury mechanism was blunt objects (37.82%). Compared with the other two groups, the majority of surgical modalities were cataract extraction (27.12%) in the CGI group, combined anterior-posterior surgery (34.79%) in the OGI group, and cyclocryotherapy/cyclophotoagulation (49.1%) in the CI group. The CI group had higher times of hospitalization (3.542 ± 0.242) and hospitalization duration (8.373 ± 0.743 days), whereas the OGI group had more operation expense ($ 1476.729 ± 11.047) and medical consumables expense per head ($ 962.578 ± 25.801). CONCLUSION: Blunt injury, males, adults, farmers, and rural patients were high-risk factors for posttraumatic glaucoma. Chemical-induced glaucoma management requires a longer hospitalization period, while OGI requires more medical expenditure. This knowledge provides a new reference for clinicians to accurately diagnose and intervene in posttraumatic glaucoma. It also suggests that more education and long-term surveillance are needed regarding the presence of glaucoma after ocular trauma.

20.
Acta Diabetol ; 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38853179

RESUMEN

AIMS: To evaluate the association between subfoveal choroidal thickness (SFCT) and diabetic macular edema (DME). DESIGN: A systematic review and meta-analysis. METHODS: A retrospective or prospective study comparing SFCT in diabetic retinopathy (DR) patients with and without DME was included. The data were collected from published studies retrieved from PubMed, Web of Science, Embase, Ovid Medline, and Cochrane Library. The final search was conducted on July 2, 2023. Heterogeneity was assessed using I2 statistics, and a random-effects model was used for the meta analysis. This study calculated the weighted mean difference (WMD) and 95% confidence interval (CI) for SFCT. RESULTS: A total of 26 relevant studies were identified, involving a combined sample size of 3201 eyes (1302 DR-DME eyes and 1899 DR-no DME eyes). The results showed no significance between DR-DME and DR-no DME (WMD = - 3.57 µm; 95% CI -26.54 to 19.41 µm; P = 0.76). Sub-analysis based on nonproliferative diabetic retinopathy (NPDR) and proliferative diabetic retinopathy (PDR) subgroups showed that the SFCT of NPDR-DME was significantly thinner than that of NPDR-no DME eyes (WMD = - 19.80 µm; 95% CI - 34.55 to - 5.04 µm; P = 0.009), while there was no significance in SFCT between PDR-DME and PDR-no DME (WMD = - 26.45 µm; 95% CI - 104.00 to 51.11 µm; P = 0.50). CONCLUSION: The SFCT was thinner in NPDR-DME eyes compared to NPDR-no DME eyes. Thinning SFCT might cause retinal hypoxia, and play an important role in DME occurrence. Additionally, this study highlights the importance of considering DR grades and treatment history when evaluating SFCT between DME and no DME.

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