Objective:To evaluate the antibacterial activity of Cinnamomum verum(C.verum) from32 different essential oils against cariogenic bacteria,Streptococcus mutans(S.mutans)and Streptococcus sobrinus(S.sobrinus).Methods:Th...Objective:To evaluate the antibacterial activity of Cinnamomum verum(C.verum) from32 different essential oils against cariogenic bacteria,Streptococcus mutans(S.mutans)and Streptococcus sobrinus(S.sobrinus).Methods:The antibacterial activities of each essential oil were individually investigated against S.mutans and S.sobrinus.The essential oil of C.verum was selected for further evaluation against S.mutans and S.sobrinus.Gas chromatography mass spectrometry was used to determine the major constituents of C.verum essential oil.In addition,the minimum inhibitory concentration(MIC) and minimum bactericidal concentration of the most effective constituent was investigated.Results:The essential oil from C.verum exhibited the greatest antibacterial activity.Gas chromatography mass spectrometry analysis revealed that the major components of C.verum essential oil were cinnamaldehyde(56.3%),cinnamyl acetate(7.1%) and bphellandrene(6.3%).The MIC of cinnamaldehyde was measured using broth dilution assays.The MIC of cinnamaldehyde was 0.02%(v/v) against both bacterial strains tested.The minimum bactericidal concentration of cinnamaldehyde against S.mutans and S.sobrinus were 0.2% and 0.1%(v/v),respectively.Conclusions:The essential oil of C.verum and its major component cinnamaldehyde possessed considerable in vitro antibacterial activities against cariogenic bacteria,S.mutans and S.sobrinus strains.These results showed that the essential oil of C.verum and its bioactive component,cinnamaldehyde,have potential for application as natural agents for the prevention and treatment of dental caries.展开更多
Removal experiments of phenol, aniline, 2,4-dichlorophenol, nonylphenol and bisphenol A (BPA) using Spirodela polyrrhiza- bacterial associations revealed that all compounds but BPA underwent accelerated removal. The...Removal experiments of phenol, aniline, 2,4-dichlorophenol, nonylphenol and bisphenol A (BPA) using Spirodela polyrrhiza- bacterial associations revealed that all compounds but BPA underwent accelerated removal. The mechanisms differed depending on the substrates. It was found that S. polyrrhiza has a great ability to release phenolic compound-rich root exudates, and the exudates seem to stimulate bacterial degradation of a variety of aromatic compounds.展开更多
High ambient temperatures are a critical challenge in the poultry industry which is a key producer of the animal-based food.To evaluate heat stress levels,various parameters have been used,including growth rates,blood...High ambient temperatures are a critical challenge in the poultry industry which is a key producer of the animal-based food.To evaluate heat stress levels,various parameters have been used,including growth rates,blood metabolites,and hormones.The most recent advances have explored expression profiling of genes that may play vital roles under stress.A high ambient temperature adversely affects nutrient uptake and is known to modulate the expression of genes encoding for sodium-dependent glucose transporters,glucose transporters,excitatory amino acid transporters,and fatty acidbinding proteins which are responsible for the absorption of macronutrients in the intestine.Various defensive activities are stimulated to protect the cell of different tissues from the heat-generated stress,including expression of early stress response genes coding for heat shock protein(HSP),c-FOS like protein,brain-derived neurotrophic factor(BDNF),and neuronal nitric oxide synthase(nNOS);antioxidant enzyme genes such as superoxide dismutase(SOD),catalase(CAT),and nicotinamide adenine dinucleotide phosphate oxidase(NOX4);and immune-related genes such as cytokines and toll-like receptors(TLRs).The potential role of HSPs in protecting the cell from stress and their presence in several tissues make them suitable markers to be evaluated under heat stress.BDNF and c-FOS genes expressed in the hypothalamus help cells to adapt to an adverse environment.Heat causes damage to the cell by generating reactive oxygen species(ROS).The NOX4 gene is the inducer of ROS under heat stress,which is in turns controlled by antioxidant enzymes such as SOD and CAT.TLRs are responsible for protecting against pathogenic attacks arising from enhanced membrane permeability,and cytokines help in controlling the pathogen and maintaining homeostasis.Thus,the evaluation of nutrient transporters and defense mechanisms using the latest molecular biology tools has made it possible to shed light on the complex cellular mechanism of heat-stressed chickens.As the impacts of heat stress on the above-mentioned aspects are beyond the extent to which the reduced growth performance could be explained,heat stress has more specific effects on the regulation of these genes than previously thought.展开更多
Objective:To determine the effects of different cytokinins at various concentrations onin vitro shoot multiplication of an important medicinal plant.Methods:Nodal explants(1.5-2.0 cm)of Sophora tonkinensiswere used.Mu...Objective:To determine the effects of different cytokinins at various concentrations onin vitro shoot multiplication of an important medicinal plant.Methods:Nodal explants(1.5-2.0 cm)of Sophora tonkinensiswere used.Multiple shoots were induced from nodal explants cultured onthe Murashige and Skoog(MS)medium supplemented with 0.0,0.5,1.0,2.0,4.0,8.0,or 16.0μmol2-isopentyladenine(2iP),N6 benzyladenine,kinetin or thiadiazuron.Results:Among the fourinvestigated cytokinins,2iP showed the best response for shoot multiplication.Maximum shootinduction(75%)was achieved on the MS medium supplemented with 2.0μmol 2iP,with a meannumber of 5.0 shoots per explant.In comparison to other cytokinins tried,2iP showed the highestshoot elongation with a mean shoot length of 4.8 cm.Root initiation was observed within 15 dwithin the transfer of shoots onto the MS basal medium,and the rooting percentage was 100%with a mean number of 5.4 roots per shoot and root length of 6.2 cm over a period of 4 weeks.Thehealthy plants,hardened and transferred to a greenhouse for proper acclimatization,exhibited100%survival.Conclusions:It can be summarized that 2iP is the optimal plant growth regulatorforSophoramultiplication.展开更多
To evaluate the response of alfalfa to water deficit (WD) stress, WD-induced candidates were investigated through a proteomic approach. Alfalfa seedlings were exposed to WD stress for 12 and 15 days respectively, fo...To evaluate the response of alfalfa to water deficit (WD) stress, WD-induced candidates were investigated through a proteomic approach. Alfalfa seedlings were exposed to WD stress for 12 and 15 days respectively, followed by 3 days re-watering. Water deficit increased H202 content, lipid peroxidation, DPPH (1,1-diphenyl-2-picrylhydrazyl)-radical scavenging activity, and the free proline level in alfalfa roots. Root proteins were extracted and separated by two-dimentional polyacrylamide gel electrophoresis (2-DE). A total of 49 WD-responsive proteins were identified in alfalfa roots; 25 proteins were reproducibly found to be up-regulated and 24 were down-regulated. Two proteins, namely cytosolic ascorbate peroxidase (APx2) and putative F-box protein were newly detected on 2-DE maps of WD-treated plants. We identified several proteins including agamous-like 65, albumin b-32, inward rectifying potassium channel, and auxin-independent growth promoter. The identified proteins are involved in a variety of cellular functions including calcium signaling, abacisic acid (ABA) biosynthesis, reactive oxygen species (ROS) regulation, transcription/translation, antioxidant/detoxification/stress defense, energy metabolism, signal transduction, and storage. These results indicate the potential candidates were responsible for adaptive response in alfalfa roots.展开更多
Chinese cabbage was cultivated in upland soil with the addition of biochar in order to investigate the potential for reduction of greenhouse gas emissions. Barley straw biochar(BSB) was introduced in a Wagner pot(1/50...Chinese cabbage was cultivated in upland soil with the addition of biochar in order to investigate the potential for reduction of greenhouse gas emissions. Barley straw biochar(BSB) was introduced in a Wagner pot(1/5000a) in amounts of 0(BSB0, control), 100(BSB100), 300(BSB300), and 500(BSB500) kg 10a^(-1). After the addition of BSB into the upland soil, carbon dioxide(CO_2) emission increased while methane(CH_4) and nitrous oxide(N_2O) emissions decreased. The highest CO2 flux was measured for the BSB500 sample,(84.6 g m^(-2)) followed by BSB300, BSB100, and BSB0 in decreasing order. Relative to those of control, the total CH_4 flux and N_2O flux for the BSB500 treatment were lower by 31.6% and 26.1%, respectively. The global warming potential(GWP) of the treatment without biochar was 281.4 g CO_2 m-2 and those for treatments with biochar were in the range from 194.1 to 224.9 g CO_2 m^(-2). Therefore, introducing BSB into upland soil to cultivate Chinese cabbages can reduce the global warming potential.展开更多
The antioxidative properties of phlorotannins isolated from the brown alga Eisenia bicyclis were measured using the H-ORAC (Hydrophilic Oxygen Radical Absorbance Capacity) method. The ORAC values of phloroglucinol and...The antioxidative properties of phlorotannins isolated from the brown alga Eisenia bicyclis were measured using the H-ORAC (Hydrophilic Oxygen Radical Absorbance Capacity) method. The ORAC values of phloroglucinol and it’s oligomers: eckol, fucofuroeckol A, phlorofucofuroeckol A, dieckol, 8,8’-bieckol, were 2.57 ± 0.14, 4.97 ± 0.36, 9.82 ± 0.70, 8.97 ± 0.89, 10.22 ± 0.85, 8.62 ± 0.92 μmol Trolox equivalent/μmol, respectively. With the exception of eckol, the ORAC values of tested phlorotannins were higher than those of the well-known antioxidants (epigallocatechin gallate, resveratrol and L-ascorbic acid) used as positive controls. As a result of comparing with known ORAC values, it was found that the dieckol and fucofuroeckol A had stronger antioxidant activity than representative polyphenols (e.g., kaempferol, quercetin, myricetin and chlorogenic acid) derived from terrestrial plants.展开更多
Objective: To investigate anti-quorum sensing(anti-QS) and anti-biofilm formation(antiBF) activities of the ethanol extracts of 388 plants. Methods: The anti-QS activity of the plant extracts was evaluated by disc-dif...Objective: To investigate anti-quorum sensing(anti-QS) and anti-biofilm formation(antiBF) activities of the ethanol extracts of 388 plants. Methods: The anti-QS activity of the plant extracts was evaluated by disc-diffusion assays using the bio-reporter strain, Chromobacterium violaceum CV017. Pseudomonas aeruginosa PAO1, Yersinia enterocolitica ATCC 9610, and Agrobacterium tumefaciens C58, which possess QS systems, were used to evaluate the antiBF activity of the plant extracts. Results: Among 388 plant extracts, the Cornus controversa(C. controversa) and Cynanchum wilfordii extracts exhibited the strongest anti-QS activity. The C. controversa extract exhibited anti-BF activity against Pseudomonas aeruginosa, Yersinia enterocolitica and Agrobacterium tumefaciens, whereas the Cynanchum wilfordii extract exhibited no anti-BF activity against Pseudomonas aeruginosa. In addition, the C. controversa extract suppressed soft rot of cabbage. Conclusions: The C. controversa extract inhibits bacterial QS and BF, and is capable of controlling soft rot. Therefore, this extract has potential for the prevention and treatment of bacterial infections and for the development of alternatives to antibiotics.展开更多
In commercial greenhouses, senescent flower petals or flowers of vegetables such as tomato, strawberry, hot pepper and zucchini squash were blighted to be removed from fruits within five days after spraying of Trichod...In commercial greenhouses, senescent flower petals or flowers of vegetables such as tomato, strawberry, hot pepper and zucchini squash were blighted to be removed from fruits within five days after spraying of Trichoderma harzianum YC459 (TORY, JGreen Inc.), a biocontrol agent with good and consistent efficacy as chemical fungicides for the control of gray mold rot caused by B. cinerea. The mechanism for selective colonization of senescent floral tissues by T. harzianum YC459 was elucidated using fresh and senescent (4 days and 14 days after pollination, respectively) floral tissues of zucchini squash (Cucurbita moschata Duchesne) . The spores of T. harzianum YC459 were produced much more on water agar and liquid culture media supplemented with 5% dry powder of senescent floral tissues than with fresh tissues during 15 days incubation. Mycelial growth was also much better in the media with senescent tissues than with fresh tissues. Enzyme activities of carboxymethyl cellulase, amylase and polygalacturonase in the liquid media, which might be involved in the colonization and degradation of tissues by T. harzianum YC459 were compared. The activities of three enzymes were significantly higher in the media with senescent floral tissues than with fresh floral tissues reaching to the maximum during 9 to 12 days of incubation. Especially, the activities of carboxymethyl cellulase and polygalacturonase of T. harzianum YC459 were much higher than those of other Trichoderma species, T. asperellum, T. viride and T. koningii in the liquid media with senescent floral tissues. Based on the results, the selective colonization and degradation of senescent floral tissues, an important habitat for B. cinerea, may be another mechanism for the biocontrol of gray mold rot of vegetables by T. harzianum YC459.展开更多
For some locally bounded function f measurable on the interval [0,∞) we have estimated the rate of convergence of the modified Szasz-Mirakyan operators Mnf at those points x∈[0,∞) at which one sided limits f(±...For some locally bounded function f measurable on the interval [0,∞) we have estimated the rate of convergence of the modified Szasz-Mirakyan operators Mnf at those points x∈[0,∞) at which one sided limits f(±) exist. We have used the Chanturiya's modulus of variation. Our result improves the estimate of [1], [3], [4], [5], [6] and [9].展开更多
Cheonggukjang is a soybean paste made by fermenting whole cooked soybeans with Bacillus subtilis. Cheonggukjang contains a fibrinolytic enzyme that could provide clinical applications for removing blood clots. In the ...Cheonggukjang is a soybean paste made by fermenting whole cooked soybeans with Bacillus subtilis. Cheonggukjang contains a fibrinolytic enzyme that could provide clinical applications for removing blood clots. In the present study, the term "cheonggukjang kinase" (CGK) was used to refer to this fibrinolytic enzyme. The thrombolytic effects of CGK were analyzed in a rat model of cerebral embolic stroke produced by middle cerebral artery occlusion (MCAO). Results from fibrin and platelet-rich clot lysis assays demonstrated that thrombolytic activity was greatest in CGKs, which were cultured for 40 hours. In addition, T50, the time needed to decompose 50% of the clot, did not change with plasminogen treatment, indicating that CGK was not a plasminogen activator, but was rather presumed to act as a plasmin-like protein. An intravenous infusion of CGK (1 U plasmin-like activity/100 μg CGK/kg) at 1 hour after MCAO resulted in removal of clots in a rat model of cerebral embolic stroke. CGK-treated groups exhibited a significant dose-dependent reduction in infarct volume. CGK treatment also improved functional recovery, as assessed by neurological deficit scores. Decreased infarct volume and improved functional recovery following CGK treatment was greater compared with recombinant tissue plasminogen activator (10 mg/kg). These results suggested that CGK effectively reduced infarct volume and improved functional recovery following ischemic brain injury. CGK exhibits a number of potential clinical applications ir the treatment of cerebral embolic stroke.展开更多
Rice plant and soil are playing vital role for produce of methane (CH4) emission from flooded rice soil. Contribution of rice plants and cover crop biomass amended soil on methane emission has not been yet studied und...Rice plant and soil are playing vital role for produce of methane (CH4) emission from flooded rice soil. Contribution of rice plants and cover crop biomass amended soil on methane emission has not been yet studied under different cover crop biomass incorporated in paddy fields. Closed-chamber method was used to estimate CH4 emission rates during rice cultivation under soil plus rice plants and soil alone condition. Soil plus rice plants chambers 62 × 62 × 112 cm3 and soil alone chambers 20 × 20 cm2 were placed at the same time during rice cultivation (0 days after rice transplanting). Therefore, to evaluate the contribution of soil plus rice plants and soil alone on methane (CH4) emission under different rates of cover crop biomass incorporated soil during rice cultivation. Methane emission from soil plus rice plants increased up to 53 days after transplanting (DAT) and then it’s decreased and continued till harvesting. It was found that ca. 47% - 52% CH4 was mediated by rice plants and ca. 48% - 53% through rice soil alone under 12 Mg·ha-1 cover crop biomass incorporated treated plots. Whereas, only ca. 9% - 10% CH4 emission was mediated by rice plants and ca. 90% - 91% by rice soil alone when 0 and 3 Mg·ha-1 cover crop biomass was incorporated. Therefore, it could be concluded that rice soil alone was more influenced for CH4 emission than rice plants in paddy fields.展开更多
Introduction: In developed countries, HIV care is mostly provided by trained specialist healthcare professionals. Due to the increasing demand for HIV care, pressure on healthcare providers to reduce cost and the curr...Introduction: In developed countries, HIV care is mostly provided by trained specialist healthcare professionals. Due to the increasing demand for HIV care, pressure on healthcare providers to reduce cost and the current global economic constraints, many developed countries are searching for alternative HIV care models. This review aims to consider whether HIV treatment and care can be provided as effectively and safely by doctors and nurses with no HIV-specialist training compared to those with HIV-specialist training. Methods: Three electronic bibliographic databases MEDLINE, EMBASE and the Cochrane Library were searched for studies conducted between January 1996 and March 2015. Manual searches of reference lists of all relevant reports retrieved from the electronic databases were conducted. All comparative studies examining the quality of HIV care provided by different types of healthcare providers in developed countries were included. Results: Nine observational studies involving 27,015 patients were included in the review. Eight studies were conducted in the USA and one study in Switzerland. Healthcare providers with HIV-related expertise and or training and those without HIV-related expertise or training who collaborated with providers with HIV-related expertise and or training outperformed other healthcare providers in many virological, immunological and ART-related outcomes. Conclusion: This review found moderate quality evidence that HIV care can be provided effectively by non-HIV specialists if they have access to HIV specialists or experts for advice and support.展开更多
Monolayer barriers called evapotranspiration (ET) covers were developed as alternative final cover systems in waste landfills but high-quality soil remains a limiting factor in these cover systems. Coal bottom ash was...Monolayer barriers called evapotranspiration (ET) covers were developed as alternative final cover systems in waste landfills but high-quality soil remains a limiting factor in these cover systems. Coal bottom ash was evaluated to be a very good alternative to soil in previous tests and a combination of soil (65% wt.wt-1) and coal bottom ash (35% wt.wt-1) was evaluated to be the most feasible materials for ET cover systems. In our pot test, selected manure compost as soil amendment for the composite ET cover system, which was made of soil and bottom ash at ca. 40 Mg.ha-1 application level was very effective to promote vegetation growth of three plants;namely, garden cosmos (Cosmosbipinnatus), Chinese bushclover (Lespedezacuneata), and leafy lespedeza (Lespedeza cyrtobotrya). To evaluate the effect of compost application on plant growth in an ET vegetative cover system, two couples of lysimeters, packed with soil and a mixture of soil and bottom ash, were installed in a pilot landfill cover system in 2007. Manure composts were applied at the rates of 0 and ?40 Mg.ha-11before sowing the five plant species, i.e.indigo-bush (Amorphafruticosa), Japanese mugwort (Artemisia princeps, Arundinella hirta, Lespedezacuneata, and Lespedezacyrtobotrya). Unseeded native plant (green foxtail,Setaria viridis) was dominant in all treatments in the 1st year after installation while the growth of the sown plants significantly improved over the years. Total biomass productivity significantly increased with manure compost application, and more significantly increased in the composite ET cover made of soil and bottom ash treatment compared to the single soil ET cover, mainly due to more improved soil nutrient levels promoting vegetation growth and maintaining the vegetation system. The use of bottom ash as a mixing material in ET cover systems has a strong potential as an alternative to fine-grained soils, and manure compost addition can effectively enhance vegetative propagation in ET cover systems.展开更多
Eucalypts are important forest resources in southwestern China,and may be tolerant to elevated ground-level ozone(O3)concentrations that can negatively affect plant growth.High CO2 may offset O3-induced effects by pro...Eucalypts are important forest resources in southwestern China,and may be tolerant to elevated ground-level ozone(O3)concentrations that can negatively affect plant growth.High CO2 may offset O3-induced effects by providing excess carbon to produce secondary metabolites or by inducing stomatal closure.Here,the effects of elevated CO2 and O3 on leaf secondary metabolites and other defense chemicals were studied by exposing seedlings of Eucalyptus globulus,E.grandis,and E.camaldulensis×E.deglupta to a factorial combination of two levels of O3(<10 nmol mol^(−1)and 60 nmol mol^(−1))and CO2(ambient:370μmol mol^(−1)and 600μmol mol^(−1))in open-top field chambers.GC-profiles of leaf extracts illustrated the effect of elevated O3 and the countering effect of high CO2 on compounds in leaf epicuticular wax and essential oils,i.e.,n-icosane,geranyl acetate and elixene,compounds known as a first-line defense against insect herbivores.n-Icosane may be involved in tolerance mechanisms of E.grandis and the hybrid,while geranyl acetate and elixene in the tolerance of E.globulus.Elevated O3 and CO2,singly or in combination,affected only leaf physiology but not biomass of various organs.Elevated CO2 impacted several leaf traits,including stomatal conductance,leaf mass per area,carbon,lignin,n-icosane,geranyl acetate and elixene.Limited effects of elevated O3 on leaf physiology(nitrogen,n-icosane,geranyl acetate,elixene)were commonly offset by elevated CO2.We conclude that E.globulus,E.grandis and the hybrid were tolerant to these O3 and CO2 treatments,and n-icosane,geranyl acetate and elixene may be major players in tolerance mechanisms of the tested species.展开更多
Research on the occurrence of perfluorochemicals (PFCs) such as perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) in the agricultural environment is lacking, in spite of their potential risk ...Research on the occurrence of perfluorochemicals (PFCs) such as perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) in the agricultural environment is lacking, in spite of their potential risk via food chain transfer from aquatic and soil-plant systems to animals and/or humans. In the present study, for the first time, soil and water samples collected from 243 different agricultural sites adjacent to waste water treatment plants (WWTPs) belonging to 81 cities and 5 provinces with different levels of industrialization in South Korea were monitored for concentrations of PFOS and PFOA by use of solid phase extraction and liquid chromatography-tandem mass spectroscopy (LC-MS/MS). Significant mean concentrations of PFOA (0.001-0.007 tJg L-1 water and 〈0.05-1.573 tJg kg-1 soil) and PFOS (0.001-0.22 tJg L-1 water and 〈0.05-0.741 pg kg-1 soil) were found in all samples. Concentrations of PFCs in soils were high, highlighting that soil is an important sink for PFCs in the agricultural environment. Samples from near WWTPs in Gyeongsang Province contained the highest concentrations of PFOS and PFOA, reflecting the concentration of heavy industry in the province. The concentrations of PFCs in agricultural water (most samples 〈0.05 pg L-~) and soils (most samples 〈1 IJg kg-~) from South Korea were less than acceptable guideline values, indicating that South Korea is not a hotspot of PFOS and PFOA contamination and that there is negligible risk to human and ecological health from these chemicals. However, further studies investigating the seasonal variation in PFOA, PFOS and other perfluorochemical concentrations in the agricultural environment are needed.展开更多
New methods to improve the bone response to metallic implants are still emerging, ranging from surface modifications of the metal to coatings and drug delivery. One further development of coatings on implants is to in...New methods to improve the bone response to metallic implants are still emerging, ranging from surface modifications of the metal to coatings and drug delivery. One further development of coatings on implants is to incorporate bioactive ions in order to stimulate the bone response without the need of drug delivery. The aim of the current study is to prepare apatite coatings containing Sr and Si using a solution method, for the purpose of further optimising the bone response to metal implants. Titanium substrates were activated to induce the formation of coatings in modified PBS solutions. Soaking in PBS solutions with different concentrations of strontium and silicate at 37℃ or 60℃ produced coatings with different morphologies, thicknesses and compositions. Ion release experiments showed simultaneous release of Sr and Si from the coatings both in PBS and Tris-HCl. Analysis of the results using the Korsmeyer-Peppas model indicate that the release of ions from the coatings was a combination of Fickian diffusion and degradation of the coatings. This study shows that it is possible to coat Ti substrates with modified apatite with ion release functionality and thereby increase the possibilities for a tailored bone response in vivo.展开更多
Sessile plants have developed a very delicate system to sense diverse kinds of endogenous developmental cues and exogenous environmental stimuli by using a simple Ca^2+ ion. Calmodulin (CAM) is the predominant Ca^2...Sessile plants have developed a very delicate system to sense diverse kinds of endogenous developmental cues and exogenous environmental stimuli by using a simple Ca^2+ ion. Calmodulin (CAM) is the predominant Ca^2+ sensor and plays a crucial role in decoding the Ca^2+ signatures into proper cellular responses in various cellular compartments in eukaryotes. A growing body of evidence points to the importance of Ca^2+ and CaM in the regulation of the transcriptional process during plant responses to endogenous and exogenous stimuli. Here, we review recent progress in the identification of transcriptional regulators modulated by Ca^2+ and CaM and in the assessment of their functional significance during plant signal transduction in response to biotic and abiotic stresses and developmental cues.展开更多
The dehydration-responsive element-binding factor 2C (DREB2C) is a member of the CBF/DREB subfamily of proteins, which contains a single APETALA2/Ethylene responsive element-binding factor (AP2/ERF) domain. To ide...The dehydration-responsive element-binding factor 2C (DREB2C) is a member of the CBF/DREB subfamily of proteins, which contains a single APETALA2/Ethylene responsive element-binding factor (AP2/ERF) domain. To identify the expression pattern of the DREB2C gene, which contains multiple transcription cis-regulatory elements in its promoter, an approximately 1.4 kb upstream DREB2C sequence was fused to the β-glucuronidase reporter gene (GUS) and the recombinant p1244 construct was transformed into Arabidopsis thaliana (L.) Heynh. The promoter of the gene directed prominent GUS activity in the vasculature in diverse young dividing tissues. Upon applying heat stress (HS), GUS staining was also enhanced in the vasculature of the growing tissues. Analysis of a series of 5'-deletions of the DREB2C promoter revealed that a proximal upstream sequence sufficient for the tissue-specific spatial and temporal induction of GUS expression by HS is localized in the promoter region between -204 and -34 bps relative to the transcriptional start site. Furthermore, electrophoretic mobility shift assay (EMSA) demonstrated that nuclear protein binding activities specific to a -120 to -32 bp promoter fragment increased after HS. These results indicate that the TATA-proximal region and some latent trans-acting factors may cooperate in HS-induced activation of the Arabidopsis DREB2C promoter.展开更多
基金Supported by Basic Science Research Program through the National Research Foundation of Korea funded by the Ministry of Education(2015R1A6A1A03031413)
文摘Objective:To evaluate the antibacterial activity of Cinnamomum verum(C.verum) from32 different essential oils against cariogenic bacteria,Streptococcus mutans(S.mutans)and Streptococcus sobrinus(S.sobrinus).Methods:The antibacterial activities of each essential oil were individually investigated against S.mutans and S.sobrinus.The essential oil of C.verum was selected for further evaluation against S.mutans and S.sobrinus.Gas chromatography mass spectrometry was used to determine the major constituents of C.verum essential oil.In addition,the minimum inhibitory concentration(MIC) and minimum bactericidal concentration of the most effective constituent was investigated.Results:The essential oil from C.verum exhibited the greatest antibacterial activity.Gas chromatography mass spectrometry analysis revealed that the major components of C.verum essential oil were cinnamaldehyde(56.3%),cinnamyl acetate(7.1%) and bphellandrene(6.3%).The MIC of cinnamaldehyde was measured using broth dilution assays.The MIC of cinnamaldehyde was 0.02%(v/v) against both bacterial strains tested.The minimum bactericidal concentration of cinnamaldehyde against S.mutans and S.sobrinus were 0.2% and 0.1%(v/v),respectively.Conclusions:The essential oil of C.verum and its major component cinnamaldehyde possessed considerable in vitro antibacterial activities against cariogenic bacteria,S.mutans and S.sobrinus strains.These results showed that the essential oil of C.verum and its bioactive component,cinnamaldehyde,have potential for application as natural agents for the prevention and treatment of dental caries.
基金supported in part by a Grant-in-Aid for Encouragement of Young Scientists A (No.21681010) from the Ministry of Education,Culture,Sports,Science and Technology of Japansupported in part by a Grant-in-Aid for Encouragement of Young Scientists B (No.19710060) from the Ministry of Education,Culture,Sports,Science and Technology of Japan
文摘Removal experiments of phenol, aniline, 2,4-dichlorophenol, nonylphenol and bisphenol A (BPA) using Spirodela polyrrhiza- bacterial associations revealed that all compounds but BPA underwent accelerated removal. The mechanisms differed depending on the substrates. It was found that S. polyrrhiza has a great ability to release phenolic compound-rich root exudates, and the exudates seem to stimulate bacterial degradation of a variety of aromatic compounds.
基金supported in part by the Korea Research Fellowship Program(2019H1D3A1A01071142)through the National Research Foundation of Korea(NRF)and by the Forest Science Technology R&D Program(2020193C10-2022-BA01)provided by Korea Forest Service(Korea Forestry Promotion Institute).
文摘High ambient temperatures are a critical challenge in the poultry industry which is a key producer of the animal-based food.To evaluate heat stress levels,various parameters have been used,including growth rates,blood metabolites,and hormones.The most recent advances have explored expression profiling of genes that may play vital roles under stress.A high ambient temperature adversely affects nutrient uptake and is known to modulate the expression of genes encoding for sodium-dependent glucose transporters,glucose transporters,excitatory amino acid transporters,and fatty acidbinding proteins which are responsible for the absorption of macronutrients in the intestine.Various defensive activities are stimulated to protect the cell of different tissues from the heat-generated stress,including expression of early stress response genes coding for heat shock protein(HSP),c-FOS like protein,brain-derived neurotrophic factor(BDNF),and neuronal nitric oxide synthase(nNOS);antioxidant enzyme genes such as superoxide dismutase(SOD),catalase(CAT),and nicotinamide adenine dinucleotide phosphate oxidase(NOX4);and immune-related genes such as cytokines and toll-like receptors(TLRs).The potential role of HSPs in protecting the cell from stress and their presence in several tissues make them suitable markers to be evaluated under heat stress.BDNF and c-FOS genes expressed in the hypothalamus help cells to adapt to an adverse environment.Heat causes damage to the cell by generating reactive oxygen species(ROS).The NOX4 gene is the inducer of ROS under heat stress,which is in turns controlled by antioxidant enzymes such as SOD and CAT.TLRs are responsible for protecting against pathogenic attacks arising from enhanced membrane permeability,and cytokines help in controlling the pathogen and maintaining homeostasis.Thus,the evaluation of nutrient transporters and defense mechanisms using the latest molecular biology tools has made it possible to shed light on the complex cellular mechanism of heat-stressed chickens.As the impacts of heat stress on the above-mentioned aspects are beyond the extent to which the reduced growth performance could be explained,heat stress has more specific effects on the regulation of these genes than previously thought.
基金This study was carried out with the support of"On-Site Cooperative Agriculture Research Project(Grant No.006330)",RDA,Republic of Korea
文摘Objective:To determine the effects of different cytokinins at various concentrations onin vitro shoot multiplication of an important medicinal plant.Methods:Nodal explants(1.5-2.0 cm)of Sophora tonkinensiswere used.Multiple shoots were induced from nodal explants cultured onthe Murashige and Skoog(MS)medium supplemented with 0.0,0.5,1.0,2.0,4.0,8.0,or 16.0μmol2-isopentyladenine(2iP),N6 benzyladenine,kinetin or thiadiazuron.Results:Among the fourinvestigated cytokinins,2iP showed the best response for shoot multiplication.Maximum shootinduction(75%)was achieved on the MS medium supplemented with 2.0μmol 2iP,with a meannumber of 5.0 shoots per explant.In comparison to other cytokinins tried,2iP showed the highestshoot elongation with a mean shoot length of 4.8 cm.Root initiation was observed within 15 dwithin the transfer of shoots onto the MS basal medium,and the rooting percentage was 100%with a mean number of 5.4 roots per shoot and root length of 6.2 cm over a period of 4 weeks.Thehealthy plants,hardened and transferred to a greenhouse for proper acclimatization,exhibited100%survival.Conclusions:It can be summarized that 2iP is the optimal plant growth regulatorforSophoramultiplication.
基金supported by the National Research Foundation of Korea (NRF) Grant (NRF-2011-616-F00013)supported by post-doctoral grantsupported by the scholarship from BK21Plus program, Ministry of Education, Republic of Korea
文摘To evaluate the response of alfalfa to water deficit (WD) stress, WD-induced candidates were investigated through a proteomic approach. Alfalfa seedlings were exposed to WD stress for 12 and 15 days respectively, followed by 3 days re-watering. Water deficit increased H202 content, lipid peroxidation, DPPH (1,1-diphenyl-2-picrylhydrazyl)-radical scavenging activity, and the free proline level in alfalfa roots. Root proteins were extracted and separated by two-dimentional polyacrylamide gel electrophoresis (2-DE). A total of 49 WD-responsive proteins were identified in alfalfa roots; 25 proteins were reproducibly found to be up-regulated and 24 were down-regulated. Two proteins, namely cytosolic ascorbate peroxidase (APx2) and putative F-box protein were newly detected on 2-DE maps of WD-treated plants. We identified several proteins including agamous-like 65, albumin b-32, inward rectifying potassium channel, and auxin-independent growth promoter. The identified proteins are involved in a variety of cellular functions including calcium signaling, abacisic acid (ABA) biosynthesis, reactive oxygen species (ROS) regulation, transcription/translation, antioxidant/detoxification/stress defense, energy metabolism, signal transduction, and storage. These results indicate the potential candidates were responsible for adaptive response in alfalfa roots.
基金supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF)funded by the Ministry of Education,Science and Technology (2012R1A2A2A01015706)the support of "Cooperative Research Program for Agriculture Science & Technology Development (Project No. PJ011227042016)" Rural Development Administration, Republic of Korea
文摘Chinese cabbage was cultivated in upland soil with the addition of biochar in order to investigate the potential for reduction of greenhouse gas emissions. Barley straw biochar(BSB) was introduced in a Wagner pot(1/5000a) in amounts of 0(BSB0, control), 100(BSB100), 300(BSB300), and 500(BSB500) kg 10a^(-1). After the addition of BSB into the upland soil, carbon dioxide(CO_2) emission increased while methane(CH_4) and nitrous oxide(N_2O) emissions decreased. The highest CO2 flux was measured for the BSB500 sample,(84.6 g m^(-2)) followed by BSB300, BSB100, and BSB0 in decreasing order. Relative to those of control, the total CH_4 flux and N_2O flux for the BSB500 treatment were lower by 31.6% and 26.1%, respectively. The global warming potential(GWP) of the treatment without biochar was 281.4 g CO_2 m-2 and those for treatments with biochar were in the range from 194.1 to 224.9 g CO_2 m^(-2). Therefore, introducing BSB into upland soil to cultivate Chinese cabbages can reduce the global warming potential.
文摘The antioxidative properties of phlorotannins isolated from the brown alga Eisenia bicyclis were measured using the H-ORAC (Hydrophilic Oxygen Radical Absorbance Capacity) method. The ORAC values of phloroglucinol and it’s oligomers: eckol, fucofuroeckol A, phlorofucofuroeckol A, dieckol, 8,8’-bieckol, were 2.57 ± 0.14, 4.97 ± 0.36, 9.82 ± 0.70, 8.97 ± 0.89, 10.22 ± 0.85, 8.62 ± 0.92 μmol Trolox equivalent/μmol, respectively. With the exception of eckol, the ORAC values of tested phlorotannins were higher than those of the well-known antioxidants (epigallocatechin gallate, resveratrol and L-ascorbic acid) used as positive controls. As a result of comparing with known ORAC values, it was found that the dieckol and fucofuroeckol A had stronger antioxidant activity than representative polyphenols (e.g., kaempferol, quercetin, myricetin and chlorogenic acid) derived from terrestrial plants.
基金supported by Basic Science Research Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Education(2015R1A6A1A03031413)Rural Development Administration,Republic of Korea(PJ00743703)
文摘Objective: To investigate anti-quorum sensing(anti-QS) and anti-biofilm formation(antiBF) activities of the ethanol extracts of 388 plants. Methods: The anti-QS activity of the plant extracts was evaluated by disc-diffusion assays using the bio-reporter strain, Chromobacterium violaceum CV017. Pseudomonas aeruginosa PAO1, Yersinia enterocolitica ATCC 9610, and Agrobacterium tumefaciens C58, which possess QS systems, were used to evaluate the antiBF activity of the plant extracts. Results: Among 388 plant extracts, the Cornus controversa(C. controversa) and Cynanchum wilfordii extracts exhibited the strongest anti-QS activity. The C. controversa extract exhibited anti-BF activity against Pseudomonas aeruginosa, Yersinia enterocolitica and Agrobacterium tumefaciens, whereas the Cynanchum wilfordii extract exhibited no anti-BF activity against Pseudomonas aeruginosa. In addition, the C. controversa extract suppressed soft rot of cabbage. Conclusions: The C. controversa extract inhibits bacterial QS and BF, and is capable of controlling soft rot. Therefore, this extract has potential for the prevention and treatment of bacterial infections and for the development of alternatives to antibiotics.
文摘In commercial greenhouses, senescent flower petals or flowers of vegetables such as tomato, strawberry, hot pepper and zucchini squash were blighted to be removed from fruits within five days after spraying of Trichoderma harzianum YC459 (TORY, JGreen Inc.), a biocontrol agent with good and consistent efficacy as chemical fungicides for the control of gray mold rot caused by B. cinerea. The mechanism for selective colonization of senescent floral tissues by T. harzianum YC459 was elucidated using fresh and senescent (4 days and 14 days after pollination, respectively) floral tissues of zucchini squash (Cucurbita moschata Duchesne) . The spores of T. harzianum YC459 were produced much more on water agar and liquid culture media supplemented with 5% dry powder of senescent floral tissues than with fresh tissues during 15 days incubation. Mycelial growth was also much better in the media with senescent tissues than with fresh tissues. Enzyme activities of carboxymethyl cellulase, amylase and polygalacturonase in the liquid media, which might be involved in the colonization and degradation of tissues by T. harzianum YC459 were compared. The activities of three enzymes were significantly higher in the media with senescent floral tissues than with fresh floral tissues reaching to the maximum during 9 to 12 days of incubation. Especially, the activities of carboxymethyl cellulase and polygalacturonase of T. harzianum YC459 were much higher than those of other Trichoderma species, T. asperellum, T. viride and T. koningii in the liquid media with senescent floral tissues. Based on the results, the selective colonization and degradation of senescent floral tissues, an important habitat for B. cinerea, may be another mechanism for the biocontrol of gray mold rot of vegetables by T. harzianum YC459.
文摘For some locally bounded function f measurable on the interval [0,∞) we have estimated the rate of convergence of the modified Szasz-Mirakyan operators Mnf at those points x∈[0,∞) at which one sided limits f(±) exist. We have used the Chanturiya's modulus of variation. Our result improves the estimate of [1], [3], [4], [5], [6] and [9].
基金the National Research Foundation of Korea,funded by the Korean Ministry of Education,Sci-ence and Technology,No.2007-0055330Inje Univer-sity Research Grant (2008)
文摘Cheonggukjang is a soybean paste made by fermenting whole cooked soybeans with Bacillus subtilis. Cheonggukjang contains a fibrinolytic enzyme that could provide clinical applications for removing blood clots. In the present study, the term "cheonggukjang kinase" (CGK) was used to refer to this fibrinolytic enzyme. The thrombolytic effects of CGK were analyzed in a rat model of cerebral embolic stroke produced by middle cerebral artery occlusion (MCAO). Results from fibrin and platelet-rich clot lysis assays demonstrated that thrombolytic activity was greatest in CGKs, which were cultured for 40 hours. In addition, T50, the time needed to decompose 50% of the clot, did not change with plasminogen treatment, indicating that CGK was not a plasminogen activator, but was rather presumed to act as a plasmin-like protein. An intravenous infusion of CGK (1 U plasmin-like activity/100 μg CGK/kg) at 1 hour after MCAO resulted in removal of clots in a rat model of cerebral embolic stroke. CGK-treated groups exhibited a significant dose-dependent reduction in infarct volume. CGK treatment also improved functional recovery, as assessed by neurological deficit scores. Decreased infarct volume and improved functional recovery following CGK treatment was greater compared with recombinant tissue plasminogen activator (10 mg/kg). These results suggested that CGK effectively reduced infarct volume and improved functional recovery following ischemic brain injury. CGK exhibits a number of potential clinical applications ir the treatment of cerebral embolic stroke.
文摘Rice plant and soil are playing vital role for produce of methane (CH4) emission from flooded rice soil. Contribution of rice plants and cover crop biomass amended soil on methane emission has not been yet studied under different cover crop biomass incorporated in paddy fields. Closed-chamber method was used to estimate CH4 emission rates during rice cultivation under soil plus rice plants and soil alone condition. Soil plus rice plants chambers 62 × 62 × 112 cm3 and soil alone chambers 20 × 20 cm2 were placed at the same time during rice cultivation (0 days after rice transplanting). Therefore, to evaluate the contribution of soil plus rice plants and soil alone on methane (CH4) emission under different rates of cover crop biomass incorporated soil during rice cultivation. Methane emission from soil plus rice plants increased up to 53 days after transplanting (DAT) and then it’s decreased and continued till harvesting. It was found that ca. 47% - 52% CH4 was mediated by rice plants and ca. 48% - 53% through rice soil alone under 12 Mg·ha-1 cover crop biomass incorporated treated plots. Whereas, only ca. 9% - 10% CH4 emission was mediated by rice plants and ca. 90% - 91% by rice soil alone when 0 and 3 Mg·ha-1 cover crop biomass was incorporated. Therefore, it could be concluded that rice soil alone was more influenced for CH4 emission than rice plants in paddy fields.
文摘Introduction: In developed countries, HIV care is mostly provided by trained specialist healthcare professionals. Due to the increasing demand for HIV care, pressure on healthcare providers to reduce cost and the current global economic constraints, many developed countries are searching for alternative HIV care models. This review aims to consider whether HIV treatment and care can be provided as effectively and safely by doctors and nurses with no HIV-specialist training compared to those with HIV-specialist training. Methods: Three electronic bibliographic databases MEDLINE, EMBASE and the Cochrane Library were searched for studies conducted between January 1996 and March 2015. Manual searches of reference lists of all relevant reports retrieved from the electronic databases were conducted. All comparative studies examining the quality of HIV care provided by different types of healthcare providers in developed countries were included. Results: Nine observational studies involving 27,015 patients were included in the review. Eight studies were conducted in the USA and one study in Switzerland. Healthcare providers with HIV-related expertise and or training and those without HIV-related expertise or training who collaborated with providers with HIV-related expertise and or training outperformed other healthcare providers in many virological, immunological and ART-related outcomes. Conclusion: This review found moderate quality evidence that HIV care can be provided effectively by non-HIV specialists if they have access to HIV specialists or experts for advice and support.
文摘Monolayer barriers called evapotranspiration (ET) covers were developed as alternative final cover systems in waste landfills but high-quality soil remains a limiting factor in these cover systems. Coal bottom ash was evaluated to be a very good alternative to soil in previous tests and a combination of soil (65% wt.wt-1) and coal bottom ash (35% wt.wt-1) was evaluated to be the most feasible materials for ET cover systems. In our pot test, selected manure compost as soil amendment for the composite ET cover system, which was made of soil and bottom ash at ca. 40 Mg.ha-1 application level was very effective to promote vegetation growth of three plants;namely, garden cosmos (Cosmosbipinnatus), Chinese bushclover (Lespedezacuneata), and leafy lespedeza (Lespedeza cyrtobotrya). To evaluate the effect of compost application on plant growth in an ET vegetative cover system, two couples of lysimeters, packed with soil and a mixture of soil and bottom ash, were installed in a pilot landfill cover system in 2007. Manure composts were applied at the rates of 0 and ?40 Mg.ha-11before sowing the five plant species, i.e.indigo-bush (Amorphafruticosa), Japanese mugwort (Artemisia princeps, Arundinella hirta, Lespedezacuneata, and Lespedezacyrtobotrya). Unseeded native plant (green foxtail,Setaria viridis) was dominant in all treatments in the 1st year after installation while the growth of the sown plants significantly improved over the years. Total biomass productivity significantly increased with manure compost application, and more significantly increased in the composite ET cover made of soil and bottom ash treatment compared to the single soil ET cover, mainly due to more improved soil nutrient levels promoting vegetation growth and maintaining the vegetation system. The use of bottom ash as a mixing material in ET cover systems has a strong potential as an alternative to fine-grained soils, and manure compost addition can effectively enhance vegetative propagation in ET cover systems.
基金supported by a Grant-in-Aid for Scientific Researches(Nos.21114008,23380078)JST Grant(No.JPMJSC18HB)the RA-GCOE project.
文摘Eucalypts are important forest resources in southwestern China,and may be tolerant to elevated ground-level ozone(O3)concentrations that can negatively affect plant growth.High CO2 may offset O3-induced effects by providing excess carbon to produce secondary metabolites or by inducing stomatal closure.Here,the effects of elevated CO2 and O3 on leaf secondary metabolites and other defense chemicals were studied by exposing seedlings of Eucalyptus globulus,E.grandis,and E.camaldulensis×E.deglupta to a factorial combination of two levels of O3(<10 nmol mol^(−1)and 60 nmol mol^(−1))and CO2(ambient:370μmol mol^(−1)and 600μmol mol^(−1))in open-top field chambers.GC-profiles of leaf extracts illustrated the effect of elevated O3 and the countering effect of high CO2 on compounds in leaf epicuticular wax and essential oils,i.e.,n-icosane,geranyl acetate and elixene,compounds known as a first-line defense against insect herbivores.n-Icosane may be involved in tolerance mechanisms of E.grandis and the hybrid,while geranyl acetate and elixene in the tolerance of E.globulus.Elevated O3 and CO2,singly or in combination,affected only leaf physiology but not biomass of various organs.Elevated CO2 impacted several leaf traits,including stomatal conductance,leaf mass per area,carbon,lignin,n-icosane,geranyl acetate and elixene.Limited effects of elevated O3 on leaf physiology(nitrogen,n-icosane,geranyl acetate,elixene)were commonly offset by elevated CO2.We conclude that E.globulus,E.grandis and the hybrid were tolerant to these O3 and CO2 treatments,and n-icosane,geranyl acetate and elixene may be major players in tolerance mechanisms of the tested species.
基金the support of the Research Program for Agricultural Science & Technology Development (PJ010896)the National Academy of Agricultural Science, Rural Development Administration, Republic of Korea
文摘Research on the occurrence of perfluorochemicals (PFCs) such as perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) in the agricultural environment is lacking, in spite of their potential risk via food chain transfer from aquatic and soil-plant systems to animals and/or humans. In the present study, for the first time, soil and water samples collected from 243 different agricultural sites adjacent to waste water treatment plants (WWTPs) belonging to 81 cities and 5 provinces with different levels of industrialization in South Korea were monitored for concentrations of PFOS and PFOA by use of solid phase extraction and liquid chromatography-tandem mass spectroscopy (LC-MS/MS). Significant mean concentrations of PFOA (0.001-0.007 tJg L-1 water and 〈0.05-1.573 tJg kg-1 soil) and PFOS (0.001-0.22 tJg L-1 water and 〈0.05-0.741 pg kg-1 soil) were found in all samples. Concentrations of PFCs in soils were high, highlighting that soil is an important sink for PFCs in the agricultural environment. Samples from near WWTPs in Gyeongsang Province contained the highest concentrations of PFOS and PFOA, reflecting the concentration of heavy industry in the province. The concentrations of PFCs in agricultural water (most samples 〈0.05 pg L-~) and soils (most samples 〈1 IJg kg-~) from South Korea were less than acceptable guideline values, indicating that South Korea is not a hotspot of PFOS and PFOA contamination and that there is negligible risk to human and ecological health from these chemicals. However, further studies investigating the seasonal variation in PFOA, PFOS and other perfluorochemical concentrations in the agricultural environment are needed.
基金This work was supported by BIOMATCELL,VINN Ex-cellence Center of Biomaterials and Cell Therapy
文摘New methods to improve the bone response to metallic implants are still emerging, ranging from surface modifications of the metal to coatings and drug delivery. One further development of coatings on implants is to incorporate bioactive ions in order to stimulate the bone response without the need of drug delivery. The aim of the current study is to prepare apatite coatings containing Sr and Si using a solution method, for the purpose of further optimising the bone response to metal implants. Titanium substrates were activated to induce the formation of coatings in modified PBS solutions. Soaking in PBS solutions with different concentrations of strontium and silicate at 37℃ or 60℃ produced coatings with different morphologies, thicknesses and compositions. Ion release experiments showed simultaneous release of Sr and Si from the coatings both in PBS and Tris-HCl. Analysis of the results using the Korsmeyer-Peppas model indicate that the release of ions from the coatings was a combination of Fickian diffusion and degradation of the coatings. This study shows that it is possible to coat Ti substrates with modified apatite with ion release functionality and thereby increase the possibilities for a tailored bone response in vivo.
文摘Sessile plants have developed a very delicate system to sense diverse kinds of endogenous developmental cues and exogenous environmental stimuli by using a simple Ca^2+ ion. Calmodulin (CAM) is the predominant Ca^2+ sensor and plays a crucial role in decoding the Ca^2+ signatures into proper cellular responses in various cellular compartments in eukaryotes. A growing body of evidence points to the importance of Ca^2+ and CaM in the regulation of the transcriptional process during plant responses to endogenous and exogenous stimuli. Here, we review recent progress in the identification of transcriptional regulators modulated by Ca^2+ and CaM and in the assessment of their functional significance during plant signal transduction in response to biotic and abiotic stresses and developmental cues.
基金supported by the Next-Generation BioGreen 21 Program (SSAC, PJ008173, Rural Development Administration,Republic of Korea)the Basic Science Research Program(20120002903, through the NRF funded by the Ministry of Education, Science and Technology, Republic of Korea)
文摘The dehydration-responsive element-binding factor 2C (DREB2C) is a member of the CBF/DREB subfamily of proteins, which contains a single APETALA2/Ethylene responsive element-binding factor (AP2/ERF) domain. To identify the expression pattern of the DREB2C gene, which contains multiple transcription cis-regulatory elements in its promoter, an approximately 1.4 kb upstream DREB2C sequence was fused to the β-glucuronidase reporter gene (GUS) and the recombinant p1244 construct was transformed into Arabidopsis thaliana (L.) Heynh. The promoter of the gene directed prominent GUS activity in the vasculature in diverse young dividing tissues. Upon applying heat stress (HS), GUS staining was also enhanced in the vasculature of the growing tissues. Analysis of a series of 5'-deletions of the DREB2C promoter revealed that a proximal upstream sequence sufficient for the tissue-specific spatial and temporal induction of GUS expression by HS is localized in the promoter region between -204 and -34 bps relative to the transcriptional start site. Furthermore, electrophoretic mobility shift assay (EMSA) demonstrated that nuclear protein binding activities specific to a -120 to -32 bp promoter fragment increased after HS. These results indicate that the TATA-proximal region and some latent trans-acting factors may cooperate in HS-induced activation of the Arabidopsis DREB2C promoter.