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BACKGROUND: Casuarina equisetifolia (C. equisetifolia) is a woody species with many excellent features. It has natural resistance against drought, salt and saline-alkali stresses. WRKY transcription factors (TFs) play significant roles in plant response to abiotic stresses, therefore, molecular characterization of WRKY gene family under abiotic stresses holds great significance for improvement of forest trees through molecular biological tools. At present, WRKY TFs from C. equisetifolia have not been thoroughly studied with respect to their role in salt and saline-alkali stresses response. The current study was conducted to bridge the same knowledge gap. RESULTS: A total of 64 WRKYs were identified in C. equisetifolia and divided into three major groups i.e. group I, II and III, consisting of 10, 42 and 12 WRKY members, respectively. The WRKY members in group II were further divided into 5 subgroups according to their homology with Arabidopsis counterparts. WRKYs belonging to the same group exhibited higher similarities in gene structure and the presence of conserved motifs. Promoter analysis data showed the presence of various response elements, especially those related to hormone signaling and abiotic stresses, such as ABRE (ABA), TGACG (MeJA), W-box ((C/T) TGAC (T/C)) and TC-rich motif. Tissue specific expression data showed that CeqWRKYs were mainly expressed in root under normal growth conditions. Furthermore, most of the CeqWRKYs were up-regulated by NaCl and NaHCO3 stresses with few of WRKYs showing early responsiveness to both stresses while few others exhibiting late response. Although the expressions of CeqWRKYs were also induced by cold stress, the response was delayed compared with other stresses. Transgenic C. equisetifolia plants overexpressing CeqWRKY11 displayed lower electrolyte leakage, higher chlorophyll content, and enhanced tolerance to both stresses. The higher expression of abiotic stress related genes, especially CeqHKT1 and CeqPOD7, in overexpression lines points to the maintenance of optimum Na+/K+ ratio, and ROS scavenging as possible key molecular mechanisms underlying salt stress tolerance. CONCLUSIONS: Our results show that CeqWRKYs might be key regulators of NaCl and NaHCO3 stresses response in C. equisetifolia. In addition, positive correlation of CeqWRKY11 expression with increased stress tolerance in C. equisetifolia encourages further research on other WRKY family members through functional genomic tools. The best candidates could be incorporated in other woody plant species for improving stress tolerance.
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Proteínas de Plantas , Factores de Transcripción , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas , Cloruro de Sodio/farmacología , Filogenia , Bicarbonato de Sodio/farmacología , Estrés Salino/genética , Estrés Fisiológico/genética , Genoma de PlantaRESUMEN
Arsenate [As(V)] is a metalloid with heavy metal properties and is widespread in many environments. Dietary intake of food derived from arsenate-contaminated plants constitutes a major fraction of the potentially health-threatening human exposure to arsenic. However, the mechanisms underlying how plants respond to arsenate stress and regulate the function of relevant transporters are poorly understood. Here, we observed that As(V) stress induces a significant Ca2+ signal in Arabidopsis (Arabidopsis thaliana) roots. We then identified a calcium-dependent protein kinase, CALCIUM-DEPENDENT PROTEIN KINASE 23 (CPK23), that interacts with the plasma membrane As(V)/Pi transporter PHOSPHATE TRANSPORTER 1;1 (PHT1;1) in vitro and in vivo. cpk23 mutants displayed a sensitive phenotype under As(V) stress, while transgenic Arabidopsis plants with constitutively active CPK23 showed a tolerant phenotype. Furthermore, CPK23 phosphorylated the C-terminal domain of PHT1;1, primarily at Ser514 and Ser520. Multiple experiments on PHT1;1 variants demonstrated that PHT1;1S514 phosphorylation is essential for PHT1;1 function and localization under As(V) stress. In summary, we revealed that plasma-membrane-associated calcium signaling regulates As(V) tolerance. These results provide insight for crop bioengineering to specifically address arsenate pollution in soils.
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Proteínas de Arabidopsis , Arabidopsis , Humanos , Arabidopsis/genética , Arabidopsis/metabolismo , Arseniatos/toxicidad , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Señalización del Calcio , Proteínas de Transporte de Fosfato/metabolismo , Fosfatos/metabolismo , Plantas Modificadas Genéticamente/metabolismo , Membrana Celular/metabolismoRESUMEN
Epidemiological evidence on the impact of airborne organic pollutants on lung function among the elderly is limited, and their underlying biological mechanisms remain largely unexplored. Herein, a longitudinal panel study was conducted in Jinan, Shandong Province, China, involving 76 healthy older adults monitored over a span of five months repetitively. We systematically evaluated personal exposure to a diverse range of airborne organic pollutants using a wearable passive sampler and their effects on lung function. Participants' pulmonary function indicators were assessed, complemented by comprehensive multi-omics analyses of blood and urine samples. Leveraging the power of interaction analysis, causal inference test (CIT), and integrative pathway analysis (IPA), we explored intricate relationships between specific organic pollutants, biomolecules, and lung function deterioration, elucidating the biological mechanisms underpinning the adverse impacts of these pollutants. We observed that bis (2-chloro-1-methylethyl) ether (BCIE) was significantly associated with negative changes in the forced vital capacity (FVC), with glycerolipids mitigating this adverse effect. Additionally, 31 canonical pathways [e.g., high mobility group box 1 (HMGB1) signaling, phosphatidylinositol 3-kinase (PI3K)/AKT pathway, epithelial mesenchymal transition, and heme and nicotinamide adenine dinucleotide (NAD) biosynthesis] were identified as potential mechanisms. These findings may hold significant implications for developing effective strategies to prevent and mitigate respiratory health risks arising from exposure to such airborne pollutants. However, due to certain limitations of the study, our results should be interpreted with caution.
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Contaminantes Atmosféricos , Humanos , Anciano , Contaminantes Atmosféricos/análisis , Contaminantes Atmosféricos/toxicidad , Masculino , Femenino , China , Estudios Longitudinales , Persona de Mediana Edad , Pulmón/efectos de los fármacos , Exposición a Riesgos Ambientales/efectos adversos , Pruebas de Función Respiratoria , Capacidad Vital/efectos de los fármacosRESUMEN
High-risk neuroblastoma (HR-NB) is an aggressive childhood cancer that responds poorly to currently available therapies and is associated with only about a 50% 5-year survival rate. MYCN amplification is a critical driver of these aggressive tumors, but so far there have not been any approved treatments to effectively treat HR-NB by targeting MYCN or its downstream effectors. Thus, the identification of novel molecular targets and therapeutic strategies to treat children diagnosed with HR-NB represents an urgent unmet medical need. Here, we conducted a targeted siRNA screening and identified TATA box-binding protein-associated factor RNA polymerase I subunit D, TAF1D, as a critical regulator of the cell cycle and proliferation in HR-NB cells. Analysis of three independent primary NB cohorts determined that high TAF1D expression correlated with MYCN-amplified, high-risk disease and poor clinical outcomes. TAF1D knockdown more robustly inhibited cell proliferation in MYCN-amplified NB cells compared with MYCN-non-amplified NB cells, as well as suppressed colony formation and inhibited tumor growth in a xenograft mouse model of MYCN-amplified NB. RNA-seq analysis revealed that TAF1D knockdown downregulates the expression of genes associated with the G2/M transition, including the master cell-cycle regulator, cell-cycle-dependent kinase 1 (CDK1), resulting in cell-cycle arrest at G2/M. Our findings demonstrate that TAF1D is a key oncogenic regulator of MYCN-amplified HR-NB and suggest that therapeutic targeting of TAF1D may be a viable strategy to treat HR-NB patients by blocking cell-cycle progression and the proliferation of tumor cells.
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Neuroblastoma , Humanos , Animales , Ratones , Proteína Proto-Oncogénica N-Myc/genética , Neuroblastoma/patología , Proliferación Celular/genética , División Celular , Fase G2 , Línea Celular Tumoral , Regulación Neoplásica de la Expresión GénicaRESUMEN
Calcium (Ca2+) is a second messenger in plants growth and development, as well as in stress responses. The transient elevation in cytosolic Ca2+ concentration have been reported to be involved in plants response to abiotic and biotic stresses. In plants, Ca2+-induced transcriptional changes trigger molecular mechanisms by which plants adapt and respond to environment stresses. The mechanism for transcription regulation by Ca2+ could be either rapid in which Ca2+ signals directly cause the related response through the gene transcript and protein activities, or involved amplification of Ca2+ signals by up-regulation the expression of Ca2+ responsive genes, and then increase the transmission of Ca2+ signals. Ca2+ regulates the expression of genes by directly binding to the transcription factors (TFs), or indirectly through its sensors like calmodulin, calcium-dependent protein kinases (CDPK) and calcineurin B-like protein (CBL). In recent years, significant progress has been made in understanding the role of Ca2+-mediated transcriptional regulation in different processes in plants. In this review, we have provided a comprehensive overview of Ca2+-mediated transcriptional regulation in plants in response to abiotic stresses including nutrition deficiency, temperature stresses (like heat and cold), dehydration stress, osmotic stress, hypoxic, salt stress, acid rain, and heavy metal stress.
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Señalización del Calcio , Calcio , Estrés Salino , Frío , CalorRESUMEN
In the field of proton conduction, the acquisition of crystalline metal-organic frameworks (MOFs) with high stability and ultrahigh proton conductivity has been of great research value and is worth continuous exploration. Here, we greenly synthesized a three-dimensional porous MOF (MOF-801-Ce) by using [(NH4)2Ce(NO3)6 and fumaric acid as starting materials and solvothermally synthesized Hf-UiO-66-NO2 by using HfCl4 and 2-nitroterephthalic acid as starting materials. A series of measurements have shown that both MOFs exhibit good water stability, acid-base stability, and thermal stability and demonstrate outstanding proton conductivity. At 100 °C and 98% relative humidity (RH), the proton conductivities (σ) could be 2.59 × 10-3 S·cm-1 for MOF-801-Ce and 0.89 × 10-3 S·cm-1 for Hf-UiO-66-NO2. To pursue higher proton conductivity, we further adopted the evaporation approach to encapsulate imidazole molecules in the pores of the two compounds, achieving the imidazole-encapsulated MOFs, Im@MOF-801-Ce and Im@Hf-UiO-66-NO2. As expected, their σ values were significantly boosted by almost an order of magnitude up to 10-2 S·cm-1. Finally, their proton-conductive mechanisms were explored in light of the structural information, gas adsorption/desorption, and other tests. The outstanding structural stability of these MOFs and their durability of the proton conduction capability manifested that they have great promise in electrochemical fields.
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This study aimed to observe the effect of anterior gradient protein 2 (AGR2) levels on intestinal barrier function in HFD animal models. For this purpose, thirty healthy male clean-grade C57BL/6 mice were randomly separated into a normal control group and a high-fat group. The normal control group was fed a normal diet, while the high-fat group was fed an HFD for a total of 8 weeks. It collected body weight changes before and after modeling of two groups of rats and serum samples and detected fasting blood glucose, total cholesterol, triglycerides, AGR2, and diamine oxidase (DAO) concentrations. It collected the expression levels of AGR2 in the colon of rats after modeling, evaluated the permeability of the colon and small intestine barrier by Ussing chamber and Evan's blue (EB) methods, and analyzed the correlation between AGR2 levels and intestinal barrier function using Pearson correlation. Results showed that when the two groups of mice were fed for 8 weeks, their body weight, fasting blood glucose, total cholesterol, and triglycerides all met the characteristics of an HFD mouse model, and the model was successfully established. When the two groups of mice were fed for 8 weeks, the serum AGR2 concentration, relative expression of AGR2 in colon tissue, Gt, and EB content of the high-fat group mice were higher than those of the normal control group, and the difference was significant (P<0.05); Meanwhile, the serum DAO concentration and Isc of the high-fat group mice were lower than those of the normal control group, with statistically significant differences (P<0.05); The relative expression levels of serum AFR2 and colon AGR2 were negatively correlated with Isc (r=-0.503, -0.623, P<0.05), and positively correlated with Gt (r=0.461, 0.560, P<0.05). There was a homogeneous distribution characteristic between the relative expression levels of serum AFR2 and serum DAO, colon AGR2, and Isc variables. It was concluded that HFD could upregulate the expression of AGR2 in mice, downregulate the level of DAO, and damage the intestinal barrier function of mice. Both serum AGR2 concentration and colonic AGR2 relative expression can participate in the regulation of colonic intestinal barrier function and can serve as potential indicators for evaluating intestinal barrier damage.
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Dieta Alta en Grasa , Funcion de la Barrera Intestinal , Masculino , Ratas , Ratones , Animales , Dieta Alta en Grasa/efectos adversos , Glucemia , Ratones Endogámicos C57BL , Peso Corporal , Modelos Animales de Enfermedad , Triglicéridos , Colesterol/metabolismoRESUMEN
Hafnium (Hf)-based UiO-66 series metal-organic frameworks (MOFs) have been widely studied on gas storage, gas separation, reduction reaction, and other aspects since they were first prepared in 2012, but there are few studies on proton conductivity. In this work, one Hf-based MOF, Hf-UiO-66-fum showing UiO-66 structure, also known as MOF-801-Hf, was synthesized at room temperature using cheap fumaric acid as the bridging ligand, and then imidazole units were successfully introduced into MOF-801-Hf to obatin a doped product, Im@MOF-801-Hf. Note that both MOF-801-Hf and Im@MOF-801-Hf demonstrate excellent thermal, water, and acid-base stabilities. Expectedly, the maximum proton conductivity (σ) of Im@MOF-801-Hf (1.46 × 10-2 S·cm-1) is nearly 4 times greater than that of MOF-801-Hf (3.98 × 10-3 S·cm-1) under 100 °C and 98% relative humidity (RH). To explore their possible practical application value, we doped them into chitosan (CS) or Nafion membranes as fillers, namely, CS/MOF-801-Hf-X, CS/Im@MOF-801-Hf-Y, and Nafion/MOF-801-Hf-Z (X, Y, and Z are the doping percentages of MOF in the membrane, respectively). Intriguingly, it was found that CS/MOF-801-Hf-6 and CS/Im@MOF-801-Hf-4 indicated the highest σ values of 1.73 × 10-2 and 2.14 × 10-2 S·cm-1, respectively, under 100 °C and 98% RH and Nafion/MOF-801-Hf-9 also revealed a high σ value of 4.87 × 10-2 S·cm-1 under 80 °C and 98% RH, which showed varying degrees of enhancement compared to the original MOFs or pure CS and Nafion membranes. Our study illustrates that these Hf-based MOFs and related composite membranes offer great potential in electrochemical fields.
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Quitosano , Estructuras Metalorgánicas , Polímeros de Fluorocarbono , Hafnio , Estructuras Metalorgánicas/química , Ácidos Ftálicos , ProtonesRESUMEN
BACKGROUND: As global warming becomes increasingly severe, it is urgent that we enhance the heat tolerance of crops. We previously reported that Arabidopsis thaliana PHOSPHOINOSITIDE-SPECIFIC PHOSPHOLIPASE C9 (AtPLC9) promotes heat tolerance. RESULTS: In this study, we ectopically expressed AtPLC9 in rice to examine its potential to improve heat tolerance in this important crop. Whereas AtPLC9 did not improve rice tolerance to salt, drought or cold, transgenic rice did exhibit greater heat tolerance than the wild type. High-throughput RNA-seq revealed extensive and dynamic transcriptome reprofiling in transgenic plants after heat stress. Moreover, the expression of some transcription factors and calcium ion-related genes showed specific upregulation in transgenic rice after heat stress, which might contribute to the enhanced heat tolerance. CONCLUSIONS: This study provides preliminary guidance for using AtPLC9 to improve heat tolerance in cereal crops and, more broadly, highlights that heterologous transformation can assist with molecular breeding.
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Grano Comestible/genética , Respuesta al Choque Térmico/genética , Respuesta al Choque Térmico/fisiología , Oryza/genética , Estrés Fisiológico/genética , Termotolerancia/genética , Termotolerancia/fisiología , Arabidopsis , Grano Comestible/fisiología , Regulación de la Expresión Génica de las Plantas , Técnicas de Transferencia de Gen , Genes de Plantas , Oryza/fisiología , Proteínas de Plantas/genética , Plantas Modificadas GenéticamenteRESUMEN
Carbonic anhydrase III (CAIII) is selectively expressed in slow-twitch myofibers in skeletal muscle. The fast-twitch to slow-twitch transformation of myofibers following denervation is accompanied by increased CAIII expression, suggesting that the effects of nerve impulses on skeletal-muscle remodeling influence CAIII expression. Here, we determined the molecular mechanisms underlying the effects of nerve conduction on CAIII expression. The results indicated that changes in skeletal-muscle [Ca2+]i altered CAIII expression. Moreover, results from the RNA-interference and over-expression experiments identified myocyte enhancer factor 2C (MEF2C) as the key transcription factor regulating [Ca2+]i-mediated changes in CAIII transcription. Additionally, chromatin immunoprecipitation experiments and luciferase assays confirmed MEF2C interaction and direct binding of the CAIII promoter between -416 and -200 base pair. Investigations of upstream cytoplasmic signaling pathways responsible for MEF2C activation revealed Ca2+/calmodulin-dependent protein kinase II (CaMKII) as the key factor involved in MEF2C-mediated regulation of CAIII expression. This study demonstrates that the Ca2+-CaMKII-MEF2C signaling pathway is the key factor involved in regulating CAIII expression in skeletal muscle. These results provide a theoretical basis supporting further investigations of changes in CAIII levels under different pathophysiological conditions and will facilitate a broader understanding of the biological functions of CAIII.
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Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/genética , Anhidrasa Carbónica III/genética , Músculo Esquelético/metabolismo , Transducción de Señal/genética , Animales , Calcio/metabolismo , Línea Celular , Citoplasma/genética , Regulación de la Expresión Génica/genética , Factores de Transcripción MEF2/genética , Ratones , Regiones Promotoras Genéticas/genética , Interferencia de ARN/fisiología , Factores de Transcripción/genética , Transcripción Genética/genéticaRESUMEN
OBJECTIVES: Inflammation as well as oxygen metabolite play important roles in renal injury during pathogenesis of rhabdomyolysis induced myoglobinuric acute renal failure (ARF). The aim of this study was to investigate the protective effects of donepezil on immune responses in rats with glycerol-induced ARF. METHODS: Sixty male rats were randomly divided into six groups, the rats were given normal saline (10 ml/kg, i.m.), glycerol (50%, 10 ml/kg, i.m.), glycerol plus dexamethasone (0.1 mg/kg, i.g.), and glycerol plus donepezil (1, 5 and 10 mg/kg, i.g.) respectively. After two weeks of glycerol injections, the kidney tissues and blood samples were harvested for future biochemical and pathology analysis. The levels of creatinine (Cr) and urea nitrogen (BUN) in plasma, the content of malondialdehyde (MDA), glutathione (GSH), and superoxide dismutase (SOD) activity, total nitric oxide synthase (TNOS), inducible nitric oxide synthase (iNOS), endothelial NO synthase (eNOS) were evaluated in renal tissues. In addition, interleukin-6 (IL-6), tumor necrosis factors-α (TNF-α) in renal tissues were also determined. RESULTS: Donepezil treatment protected rats from renal dysfunction in a dose-dependent manner and through the cholinergic anti-inflammatory pathway. Additionally, donepezil significantly reduced tubular damages, prevented neutrophil infiltration and decreased productions of the IL-6, TNF-α, nitric oxide content and oxidative damage. CONCLUSIONS: These data indicate that donepezil exerts a protective anti-inflammatory effect during ARF through the cholinergic pathway and Nitric oxide pathway. In addition, this study could provide an opportunity to overcome the effect of surgical cholinergic denervation during kidney transplantation and other injury.
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Lesión Renal Aguda/prevención & control , Antiinflamatorios/farmacología , Inhibidores de la Colinesterasa/farmacología , Donepezilo/farmacología , Mediadores de Inflamación/metabolismo , Riñón/efectos de los fármacos , Óxido Nítrico/metabolismo , Lesión Renal Aguda/metabolismo , Lesión Renal Aguda/patología , Animales , Modelos Animales de Enfermedad , Glicerol , Interleucina-6/metabolismo , Riñón/metabolismo , Riñón/patología , Masculino , Óxido Nítrico Sintasa de Tipo II/metabolismo , Óxido Nítrico Sintasa de Tipo III/metabolismo , Estrés Oxidativo/efectos de los fármacos , Ratas Sprague-Dawley , Transducción de Señal , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
Drought stress induces stomatal closure and inhibits stomatal opening simultaneously. However, the underlying molecular mechanism is still largely unknown. Here we show that S-type anion channels SLAC1 and SLAH3 mainly inhibit inward K+ (K+in) channel KAT1 by protein-protein interaction, and consequently prevent stomatal opening in Arabidopsis. Voltage-clamp results demonstrated that SLAC1 inhibited KAT1 dramatically, but did not inhibit KAT2. SLAH3 inhibited KAT1 to a weaker degree relative to SLAC1. Both the N terminus and the C terminuses of SLAC1 inhibited KAT1, but the inhibition by the N terminus was stronger. The C terminus was essential for the inhibition of KAT1 by SLAC1. Furthermore, drought stress strongly up-regulated the expression of SLAC1 and SLAH3 in Arabidopsis guard cells, and the over-expression of wild type and truncated SLAC1 dramatically impaired K+in currents of guard cells and light-induced stomatal opening. Additionally, the inhibition of KAT1 by SLAC1 and KC1 only partially overlapped, suggesting that SLAC1 and KC1 inhibited K+in channels using different molecular mechanisms. Taken together, we discovered a novel regulatory mechanism for stomatal movement, in which singling pathways for stomatal closure and opening are directly coupled together by protein-protein interaction between SLAC1/SLAH3 and KAT1 in Arabidopsis.
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BACKGROUND/AIMS: Obesity is associated with chronic inflammation and cognitive decline, and is considered a major risk factor for neurodegeneration. Meanwhile, neuroinflammation is important in the pathogenesis and progression of neurodegenerative diseases. METHODS: In this study, we tested the hypothesis that donepezil would attenuate central inflammation and oxidative damage and improve memory deficit in high-fat diet (HFD)-fed mice. After 16 weeks on a HFD, C57BL/6J mice were given either donepezil (3 mg/kg, i.p.) or saline for 4 weeks in parallel to a control diet (CD) group. Thereafter, the step-through test was used to assess learning and memory function. RESULTS: In the brain of HFD-fed mice, levels of the proinflammatory cytokines interleukin 16 and tumor necrosis factor α were reduced by donepezil treatment. Similarly, HFD-induced protein levels of advanced glycation end-products and oxidative stress in the brain were significantly decreased by donepezil treatment. CONCLUSION: Our results indicate that donepezil may reverse obesity-related central inflammation and oxidative damage and improve memory deficit in HFD-fed mice.
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Donepezilo/uso terapéutico , Inflamación/tratamiento farmacológico , Trastornos de la Memoria/etiología , Trastornos de la Memoria/psicología , Nootrópicos/uso terapéutico , Obesidad/tratamiento farmacológico , Estrés Oxidativo/efectos de los fármacos , Animales , Dieta Alta en Grasa , Productos Finales de Glicación Avanzada/sangre , Inflamación/metabolismo , Resistencia a la Insulina , Interleucina-16/sangre , Aprendizaje , Masculino , Memoria , Ratones , Ratones Endogámicos C57BL , Obesidad/metabolismo , Factor de Necrosis Tumoral alfa/sangreRESUMEN
Diverse stimuli induce stomatal closure by triggering the efflux of osmotic anions, which is mainly mediated by the main anion channel SLAC1 in plants, and the anion permeability and selectivity of SLAC1 channels from several plant species have been reported to be variable. However, the genetic identity as well as the anion permeability and selectivity of the main S-type anion channel ZmSLAC1 in maize are still unknown. In this study, we identified GRMZM2G106921 as the gene encoding ZmSLAC1 in maize, and the maize mutants zmslac1-1 and zmslac1-2 harboring a mutator (Mu) transposon in ZmSLAC1 exhibited strong insensitive phenotypes of stomatal closure in response to diverse stimuli. We further found that ZmSLAC1 functions as a nitrate-selective anion channel without obvious permeability to chloride, sulfate and malate, clearly different from SLAC1 channels of Arabidopsis thaliana, Brassica rapa ssp. chinensis and Solanum lycopersicum L. Further experimental data show that the expression of ZmSLAC1 successfully rescued the stomatal movement phenotypes of the Arabidopsis double mutant atslac1-3atslah3-2 by mainly restoring nitrate-carried anion channel currents of guard cells. Together, these findings demonstrate that ZmSLAC1 is involved in stomatal closure mainly by mediating the efflux of nitrate in maize.
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Canales Iónicos/metabolismo , Nitratos/metabolismo , Proteínas de Plantas/metabolismo , Estomas de Plantas/fisiología , Zea mays/fisiología , Aniones , Arabidopsis/genética , Permeabilidad de la Membrana Celular , Canales de Cloruro/metabolismo , Cloruros/metabolismo , Genes de Plantas , Fenotipo , Plantas Modificadas Genéticamente , Zea mays/genética , Zea mays/metabolismoRESUMEN
The increased prevalence of high temperatures (HTs) around the world is a major global concern, as they dramatically affect agronomic productivity. Upon HT exposure, plants sense the temperature change and initiate cellular and metabolic responses that enable them to adapt to their new environmental conditions. Decoding the mechanisms by which plants cope with HT will facilitate the development of molecular markers to enable the production of plants with improved thermotolerance. In recent decades, genetic, physiological, molecular, and biochemical studies have revealed a number of vital cellular components and processes involved in thermoresponsive growth and the acquisition of thermotolerance in plants. This review summarizes the major mechanisms involved in plant HT responses, with a special focus on recent discoveries related to plant thermosensing, heat stress signaling, and HT-regulated gene expression networks that promote plant adaptation to elevated environmental temperatures.
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Plantas/metabolismo , Adaptación Fisiológica/genética , Adaptación Fisiológica/fisiología , Regulación de la Expresión Génica de las Plantas/genética , Regulación de la Expresión Génica de las Plantas/fisiología , Calor , Plantas/genéticaRESUMEN
Potassium (Kâº) is an essential macronutrient for plant growth and development. Previous studies have demonstrated that Calcineurin B-Like Protein1 (CBL1) or CBL9 and CBL-Interacting Protein Kinase23 (CIPK23) regulate K⺠uptake in Arabidopsis (Arabidopsis thaliana) roots by modulating K⺠channel Arabidopsis K⺠Transporter1. In this study, we show that the protein kinase CIPK9 interacts with the calcium sensor CBL3 and plays crucial roles in K⺠homeostasis under low-K⺠stress in Arabidopsis. Arabidopsis wild-type plants showed leaf chlorotic symptoms when grown for 10 d on low-K⺠(100 µM) medium. Here, we show that plants lacking CIPK9 displayed a tolerant phenotype to low-K⺠stress, which still maintained green leaves when the wild-type plants showed typical Kâº-deficient symptoms. Overexpressing lines of CIPK9 resulted in a low-Kâº-sensitive phenotype compared with wild-type plants. Furthermore, CBL2 and CBL3 were identified as upstream regulators of CIPK9. Both CBL2- and CBL3-overexpressing lines displayed similar low-Kâº-sensitive phenotypes and K⺠contents to CIPK9-overexpressing lines. However, only cbl3 mutant plants, but not cbl2 mutant plants, showed the low-Kâº-tolerant phenotype similar to cipk9 mutants. Taken together, these results demonstrate that CIPK9 and CBL3 work together and function in K⺠homeostasis under low-K⺠stress in Arabidopsis.
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Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimología , Proteínas de Unión al Calcio/metabolismo , Homeostasis , Potasio/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Estrés Fisiológico , Adaptación Fisiológica , Agrobacterium tumefaciens/genética , Agrobacterium tumefaciens/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Transporte Biológico , Proteínas de Unión al Calcio/genética , Clonación Molecular , Medios de Cultivo/metabolismo , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Prueba de Complementación Genética , Fenotipo , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Raíces de Plantas/genética , Raíces de Plantas/metabolismo , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Canales de Potasio/genética , Canales de Potasio/metabolismo , Mapeo de Interacción de Proteínas , Proteínas Serina-Treonina Quinasas/genética , Protoplastos/metabolismo , Transcriptoma , Técnicas del Sistema de Dos HíbridosRESUMEN
Cytosolic Ca(2+) in guard cells plays an important role in stomatal movement responses to environmental stimuli. These cytosolic Ca(2+) increases result from Ca(2+) influx through Ca(2+)-permeable channels in the plasma membrane and Ca(2+) release from intracellular organelles in guard cells. However, the genes encoding defined plasma membrane Ca(2+)-permeable channel activity remain unknown in guard cells and, with some exceptions, largely unknown in higher plant cells. Here, we report the identification of two Arabidopsis (Arabidopsis thaliana) cation channel genes, CNGC5 and CNGC6, that are highly expressed in guard cells. Cytosolic application of cyclic GMP (cGMP) and extracellularly applied membrane-permeable 8-Bromoguanosine 3',5'-cyclic monophosphate-cGMP both activated hyperpolarization-induced inward-conducting currents in wild-type guard cells using Mg(2+) as the main charge carrier. The cGMP-activated currents were strongly blocked by lanthanum and gadolinium and also conducted Ba(2+), Ca(2+), and Na(+) ions. cngc5 cngc6 double mutant guard cells exhibited dramatically impaired cGMP-activated currents. In contrast, mutations in CNGC1, CNGC2, and CNGC20 did not disrupt these cGMP-activated currents. The yellow fluorescent protein-CNGC5 and yellow fluorescent protein-CNGC6 proteins localize in the cell periphery. Cyclic AMP activated modest inward currents in both wild-type and cngc5cngc6 mutant guard cells. Moreover, cngc5 cngc6 double mutant guard cells exhibited functional abscisic acid (ABA)-activated hyperpolarization-dependent Ca(2+)-permeable cation channel currents, intact ABA-induced stomatal closing responses, and whole-plant stomatal conductance responses to darkness and changes in CO2 concentration. Furthermore, cGMP-activated currents remained intact in the growth controlled by abscisic acid2 and abscisic acid insensitive1 mutants. This research demonstrates that the CNGC5 and CNGC6 genes encode unique cGMP-activated nonselective Ca(2+)-permeable cation channels in the plasma membrane of Arabidopsis guard cells.
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Proteínas de Arabidopsis/genética , Arabidopsis/genética , Canales de Calcio/metabolismo , Calcio/metabolismo , Permeabilidad de la Membrana Celular/efectos de los fármacos , GMP Cíclico/farmacología , Canales Catiónicos Regulados por Nucleótidos Cíclicos/genética , Estomas de Plantas/citología , Ácido Abscísico/farmacología , Arabidopsis/citología , Arabidopsis/efectos de los fármacos , Arabidopsis/efectos de la radiación , Proteínas de Arabidopsis/metabolismo , Bloqueadores de los Canales de Calcio/farmacología , Dióxido de Carbono/farmacología , Cationes , GMP Cíclico/análogos & derivados , Canales Catiónicos Regulados por Nucleótidos Cíclicos/metabolismo , Ecotipo , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Genes de Plantas/genética , Activación del Canal Iónico/efectos de los fármacos , Activación del Canal Iónico/genética , Activación del Canal Iónico/efectos de la radiación , Luz , Mutación/genética , Estomas de Plantas/efectos de los fármacos , Estomas de Plantas/genética , Estomas de Plantas/efectos de la radiación , Protoplastos/efectos de los fármacos , Protoplastos/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Proteínas Recombinantes de Fusión/metabolismo , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Transducción de Señal/efectos de la radiación , Fracciones Subcelulares/efectos de los fármacos , Fracciones Subcelulares/metabolismo , Fracciones Subcelulares/efectos de la radiación , Factores de Tiempo , Nicotiana/efectos de los fármacos , Nicotiana/metabolismoRESUMEN
OBJECTIVE: To observe the co-variation of acetylated histone H3 levels of peripheral blood mononuclear cells (PBMCs) and onset time of acute ischemic stroke and examine the histone H3 acetylation levels in PBMCs of acute cerebral infarction patients with different stroke subtypes and injury degrees. METHODS: The peripheral blood samples 2 ml from patients at different timepoints (1, 3, 5, 7, 14 d) from April 2013 to July 2013 and normal controls were collected to observe the dynamic change of Ac-H3 levels of PBMCs in cerebral infarction patients. Also between April 2013 and October 2013, blood samples from 103 patients within 7 d after acute ischemic stroke were collected. Global histone was extracted by assay kit and differential histone H3 acetylation levels were determined by Western blot. All patients were measured by the Oxfordshire Community Stroke Project (OCSP) classification and National Institutes of Health Stroke Scale (NIHSS) score. RESULTS: The levels of acetylated histone H3 in PBMCs of acute cerebral infarction patients started to decrease as early as 1 d and remained below those normal controls for at least 7 d after stroke. It fulfilled the minimum at 3 d after infarction (P < 0.001). Acetylated histone H3 levels of PBMCs differed in OCSP classification (P < 0.05) and reached a nadir in TACI group. Histone H3 acetylation levels of PBMCs were major affecting factors of neurological injury severity and negatively correlated with it through multiple regressive analysis (ß = -0.297, P = 0.001). CONCLUSION: Histone H3 acetylation level in PBMCs of acute cerebral infarction patients is lower than healthy persons. And it decreases markedly in TACI group and patients with severe neurological dysfunction.
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Infarto Cerebral/sangre , Histonas/sangre , Leucocitos Mononucleares/química , Acetilación , Enfermedad Aguda , HumanosRESUMEN
HYPOTHESIS: Elucidation of the micro-mechanisms of sol-gel transition of gelling glucans with different glycosidic linkages is crucial for understanding their structure-property relationship and for various applications. Glucans with distinct molecular chain structures exhibit unique gelation behaviors. The disparate gelation phenomena observed in two methylated glucans, methylated (1,3)-ß-d-glucan of curdlan (MECD) and methylated (1,4)-ß-d-glucan of cellulose (MC), notwithstanding their equivalent degrees of substitution, are intricately linked to their unique molecular architectures and interactions between glucan and water. EXPERIMENTS: Density functional theory and molecular dynamics simulations focused on the electronic property distinctions between MECD and MC, alongside conformational variations during thermal gelation. Inline attenuated total reflection Fourier transform infrared spectroscopy tracked secondary structure alterations in MECD and MC. To corroborate the simulation results, additional analyses including circular dichroism, rheology, and micro-differential scanning calorimetry were performed. FINDINGS: Despite having similar thermally induced gel networks, MECD and MC display distinct physical gelation patterns and molecular-level conformational changes during gelation. The network of MC gel was formed via a "coil-to-ring" transition, followed by ring stacking. In contrast, the MECD gel comprised compact irregular helices accompanied by notable volume shrinkage. These variations in gelation behavior are ascribed to heightened hydrophobic interactions and diminished hydrogen bonding in both systems upon heating, resulting in gelation. These findings provide valuable insights into the microstructural changes during gelation and the thermo-gelation mechanisms of structurally similar polysaccharides.
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Geles , Simulación de Dinámica Molecular , Geles/química , Metilación , Temperatura , beta-Glucanos/química , Glicósidos/química , Teoría Funcional de la Densidad , Glucanos/química , Celulosa/químicaRESUMEN
Fritillaria unibracteata (FRU) belongs to the genus Fritillaria of the Liliaceae family. It is one of the original plants of the Chinese medicinal material "Chuanbeimu" and also a biological resource featured in the Tibetan Plateau of China. The dried bulbs of FRU are used in traditional Chinese medicine. The chemical constituents of FRU that have been isolated and identified include alkaloids, sterols, organic acids and their esters, nucleosides and volatile oils. FRU has antitussive, expectorant, anti-asthmatic, anti-inflammatory, antibacterial, acute lung injury-reducing, antifibrosis, antitumor, and other pharmacological effects. This valuable plant has an extremely high market demand, and over the years, due to over-exploitation, FRU has now been listed as a key species that is endangered and scarcely cultivated in China as a traditional Chinese medicinal herb. However, research on FRU is rare, and its effective components, resource control, and mechanisms of action need further study. This review systematically discusses the herbal characteristics, resource distribution, chemical composition, biosynthesis, pharmacological effects, clinical application, and breeding techniques of FRU, hoping to provide a reference for further research and the use of FRU.