Shaping Copper Oxide Layers on Gold Nanoparticle Ensembles by Controlled Electrodeposition with Single Particle Scatterometry.

Electrodeposition of copper on gold nanoelectrode ensembles result in the formation of uniform copper oxide layers on individual nanoparticles. A linear sweep of voltammetric change induces three distinct morphologies dependent upon particle density. Ex situ imaging and in situ scatterometry at a single-particle level identifies multi-step electrochemical growth sequences that deviated from classical nucleation and growth pathways. In addition, the study demonstrated the possibility of synthesizing sophisticated structures based on the symmetry of nanoelectrodes. This result guides the nanoscale morphology control of electrode ensembles with potential application in electrocatalysis and sensing.

Tomato Yellow Leaf Curl Virus Infection in a Monocotyledonous Weed (Eleusine indica).

Tomato yellow leaf curl virus (TYLCV) is one of the most important plant viruses belonging to the genus Begomovirus of the family Geminiviridae. To identify natural weed hosts that could act as reservoirs of TYLCV, 100 samples were collected at a TYLCV-affected tomato farm in Iksan from 2013 to 2014. The sample weeds were identified as belonging to 40 species from 18 families. TYLCV was detected in 57 samples belonging to 28 species through polymerase chain reaction using root samples including five species (Eleusine indica, Digitaria ciliaris, Echinochloa crus-galli, Panicum dichotomiflorum, and Setaria faberi) from the family Poaceae. Whitefly Bemisia tabaci-mediated TYLCV transmission from TYLCV-infected E. indica plants to healthy tomatoes was confirmed, and inoculated tomatoes showed typical symptoms, such as leaf curling and yellowing. In addition, TYLCV was detected in leaf and root samples of E. indica plants inoculated by both whitefly-mediated transmission using TYLCV-viruliferous whitefly and agro-inoculation using a TYLCV infectious clone. The majority of mastreviruses infect monocotyledonous plants, but there have also been reports of mastreviruses that can infect dicotyledonous plants, such as the chickpea chlorotic dwarf virus. No exception was reported among begomoviruses known as infecting dicots only. This is the first report of TYLCV as a member of the genus Begomovirus infecting monocotyledonous plants.

Structural complexity induced by {110} blocking of cysteine in electrochemical copper deposition on silver nanocubes.

Morphology evolution into intricate structures at the nanoscale is hard to understand, but we can get critical information from the combination of ex situ and in situ spectroelectrochemical techniques. In this study, we investigated the structural complexity generated during electrochemical Cu deposition on individual Ag nanocubes, which was driven by surface regulating cysteine molecules. During the deposition process, selective nucleation occurred on the Ag nanocubes by underpotential deposition, and then sequential structural evolution to a windmill morphology was observed. By adjusting the cysteine coverage, diverse structures were yielded, including face-overgrown, four-leaf clover, and octapod-like structures. Structural analysis along the crystallographic directions demonstrated that cysteine molecules exclusively blocked the growth along 110 and relatively promoted the growth along 100 and 111, respectively. Interestingly, all morphologies maintained a highly symmetric nature from the pristine cube, despite being diverse and sophisticated. These findings would be essential to design complex morphologies and achieve desirable optical and catalytic properties.

Ethanol Extract of Lilium Bulbs Plays an Anti-Inflammatory Role by Targeting the IKK[Formula: see text]/[Formula: see text]-Mediated NF-[Formula: see text]B Pathway in Macrophages.

Lilium bulbs have long been used as Chinese traditional medicines to alleviate the symptoms of various human inflammatory diseases. However, mechanisms of Lilium bulb-mediated anti-inflammatory activity and the bioactive components in Lilium bulbs remain unknown. In the present study, the anti-inflammatory activity of Lilium bulbs and the underlying mechanism of action were investigated in macrophages using Lilium bulb ethanol extracts (Lb-EE). In a dose-dependent manner, Lb-EE inhibited nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW264.7 cells and bone marrow-derived macrophages (BMDMs) without causing significant cytotoxicity. Lb-EE also down-regulated mRNA expression of inflammatory genes in LPS-stimulated RAW264.7 cells, which included inducuble nitric oxide synthase (iNOS), cyclooxygenase-2 (COX2), and tumor necrosis factor-[Formula: see text] (TNF-[Formula: see text]). Furthermore, Lb-EE markedly restored LPS-induced morphological changes in RAW264.7 cells to a normal morphology. HPLC analysis identified quercetin, luteolin, and kaempferol as bioactive components contained in Lb-EE. Mechanistic studies in LPS-stimulated RAW264.7 cells revealed that Lb-EE suppressed MyD88- and TRIF-induced NF-[Formula: see text]B transcriptional activation and the nuclear translocation of NF-[Formula: see text]B transcription factors. Moreover, Lb-EE inhibited IKK[Formula: see text]/[Formula: see text]-induced activation of the NF-[Formula: see text]B signaling pathway and IKK inhibition significantly reduced NO production in LPS-stimulated RAW264.7 cells. Taken together, these results suggest that Lb-EE plays an anti-inflammatory role by targeting IKK[Formula: see text]/[Formula: see text]-mediated activation of the NF-[Formula: see text]B signaling pathway during macrophage-mediated inflammatory responses.

Cytoprotective Effect of Epigallocatechin Gallate (EGCG)-5'-O-α-Glucopyranoside, a Novel EGCG Derivative.

Epigallocatechin gallate (EGCG) is a well-studied polyphenol with antioxidant effects. Since EGCG has low solubility and stability, many researchers have modified EGCG residues to ameliorate these problems. A novel EGCG derivative, EGCG-5'-O-α-glucopyranoside (EGCG-5'Glu), was synthesized, and its characteristics were investigated. EGCG-5'Glu showed antioxidant effects in cell and cell-free systems. Under SNP-derived radical exposure, EGCG-5'Glu decreased nitric oxide (NO) production, and recovered ROS-mediated cell viability. Moreover, EGCG-5'Glu regulated apoptotic pathways (caspases) and cell survival molecules (phosphoinositide 3-kinase (PI3K) and phosphoinositide-dependent kinase 1 (PDK1)). In another radical-induced condition, ultraviolet B (UVB) irradiation, EGCG-5'Glu protected cells from UVB and regulated the PI3K/PDK1/AKT pathway. Next, the proliferative effect of EGCG-5'Glu was examined. EGCG-5'Glu increased cell proliferation by modulating nuclear factor (NF)-κB activity. EGCG-5'Glu protects and repairs cells from external damage via its antioxidant effects. These results suggest that EGCG-5'Glu could be used as a cosmetics ingredient or dietary supplement.

A Dominant Negative OsKAT2 Mutant Delays Light-Induced Stomatal Opening and Improves Drought Tolerance without Yield Penalty in Rice.

Stomata are the main gateways for water and air transport between leaves and the environment. Inward-rectifying potassium channels regulate photo-induced stomatal opening. Rice contains three inward rectifying shaker-like potassium channel proteins, OsKAT1, OsKAT2, and OsKAT3. Among these, only OsKAT2 is specifically expressed in guard cells. Here, we investigated the functions of OsKAT2 in stomatal regulation using three dominant negative mutant proteins, OsKAT2(T235R), OsKAT2(T285A) and OsKAT2(T285D), which are altered in amino acids in the channel pore and at a phosphorylation site. Yeast complementation and patch clamp assays showed that all three mutant proteins lost channel activity. However, among plants overexpressing these mutant proteins, only plants overexpressing OsKAT2(T235R) showed significantly less water loss than the control. Moreover, overexpression of this mutant protein led to delayed photo-induced stomatal opening and increased drought tolerance. Our results indicate that OsKAT2 is an inward- rectifying shaker-like potassium channel that mainly functions in stomatal opening. Interestingly, overexpression of OsKAT2(T235R) did not cause serious defects in growth or yield in rice, suggesting that OsKAT2 is a potential target for engineering plants with improved drought tolerance without yield penalty.

Morphology-controlled ZnO nanowire arrays for tailored hybrid composites with high damping.

Hybrid fiber reinforced composites using a nanoscale reinforcement of the interface have not reached their optimal performance in practical applications due to their complex design and the challenging assembly of their multiscale components. One promising approach to the fabrication of hybrid composites is the growth of zinc oxide (ZnO) nanowire arrays on the surface of carbon fibers to provide improved interfacial strength and out of plane reinforcement. However, this approach has been demonstrated mainly on fibers and thus still requires complex processing conditions. Here we demonstrate a simple approach to the fabrication of such composites through the growth of the nanowires on the fabric. The fabricated composites with nanostructured graded interphase not only exhibit remarkable damping enhancement but also stiffness improvement. It is demonstrated that these two extremely important properties of the composite can be controlled by tuning the morphology of the ZnO nanowires at the interface. Higher damping and flexural rigidity of these composites over traditional ones offer practical high-performance composites.

ATF-2/CREB/IRF-3-targeted anti-inflammatory activity of Korean red ginseng water extract.

ETHNOPHARMACOLOGICAL RELEVANCE: Korean Red Ginseng (KRG) is one of the representative traditional herbal medicines prepared from Panax ginseng Meyer (Araliaceae) in Korea. It has been reported that KRG exhibits a lot of different biological actions such as anti-aging, anti-fatigue, anti-stress, anti-atherosclerosis, anti-diabetic, anti-cancer, and anti-inflammatory activities. Although systematic studies have investigated how KRG is able to ameliorate various inflammatory diseases, its molecular inhibitory mechanisms had not been carried out prior to this study. MATERIALS AND METHODS: In order to investigate these mechanisms, we evaluated the effects of a water extract of Korean Red Ginseng (KRG-WE) on the in vitro inflammatory responses of activated RAW264.7 cells, and on in vivo gastritis and peritonitis models by analyzing the activation events of inflammation-inducing transcription factors and their upstream kinases. RESULTS: KRG-WE reduced the production of nitric oxide (NO), protected cells against NO-induced apoptosis, suppressed mRNA levels of inducible NO synthase (iNOS), cyclooxygenase (COX)-2, and interferon (IFN)-ß, ameliorated EtOH/HCl-induced gastritis, and downregulated peritoneal exudate-derived NO production from lipopolysaccharide (LPS)-injected mice. The inhibition of these inflammatory responses by KRG-WE was regulated through the suppression of p38, c-Jun N-terminal kinase (JNK), and TANK-binding kinase 1 (TBK1) and by subsequent inhibition of activating transcription factor (ATF)-2, cAMP response element-binding protein (CREB), and IRF-3 activation. Of ginsensides included in this extract, interestingly, G-Rc showed the highest inhibitory potency on IRF-3-mediated luciferase activity. CONCLUSION: These results strongly suggest that the anti-inflammatory activities of KRG-WE could be due to its inhibition of the p38/JNK/TBK1 activation pathway.

Overexpression of PYL5 in rice enhances drought tolerance, inhibits growth, and modulates gene expression.

Abscisic acid (ABA) is a phytohormone that plays important roles in the regulation of seed dormancy and adaptation to abiotic stresses. Previous work identified OsPYL/RCARs as functional ABA receptors regulating ABA-dependent gene expression in Oryza sativa. OsPYL/RCARs thus are considered to be good candidate genes for improvement of abiotic stress tolerance in crops. This work demonstrates that the cytosolic ABA receptor OsPYL/RCAR5 in O. sativa functions as a positive regulator of abiotic stress-responsive gene expression. The constitutive expression of OsPYL/RCAR5 in rice driven by the Zea mays ubiquitin promoter induced the expression of many stress-responsive genes even under normal growth conditions and resulted in improved drought and salt stress tolerance in rice. However, it slightly reduced plant height under paddy field conditions and severely reduced total seed yield. This suggests that, although exogenous expression of OsPYL/RCAR5 is able to improve abiotic stress tolerance in rice, fine regulation of its expression will be required to avoid deleterious effects on agricultural traits.

OsKAT2 is the prevailing functional inward rectifier potassium channels in rice guard cell.

AtKAT1 plays roles as a major channel to uptake K(+) in guard cell when stomata open in dicot model plant Arabidopsis. In a recent publication, we isolated 3 KAT-like potassium channels in rice. We expressed them in CHO cell to identify electrophysiological characteristics of the channels. OsKAT2 showed much bigger inwardly rectifying potassium channel activities among them. The histochemical X-glu staining of transgenic rice leaf blades expressing ß-glucuronidase fused with OsKAT2 promoter showed that the OsKAT2 is dominantly expressed in rice guard cell. These findings indicate that OsKAT2 may be a functional ortholog of AtKAT1 in rice. Thus this gene will be the prime target for engineering the guard cell movement to improve drought tolerance in monocot plants, including most major crops.

Unique features of two potassium channels, OsKAT2 and OsKAT3, expressed in rice guard cells.

Potassium is the most abundant cation and a myriad of transporters regulate K(+) homeostasis in plant. Potassium plays a role as a major osmolyte to regulate stomatal movements that control water utility of land plants. Here we report the characterization of two inward rectifying shaker-like potassium channels, OsKAT2 and OsKAT3, expressed in guard cell of rice plants. While OsKAT2 showed typical potassium channel activity, like that of Arabidopsis KAT1, OsKAT3 did not despite high sequence similarity between the two channel proteins. Interestingly, the two potassium channels physically interacted with each other and such interaction negatively regulated the OsKAT2 channel activity in CHO cell system. Furthermore, deletion of the C-terminal domain recovered the channel activity of OsKAT3, suggesting that the C-terminal region was regulatory domain that inhibited channel activity. Two homologous channels with antagonistic interaction has not been previously reported and presents new information for potassium channel regulation in plants, especially in stomatal regulation.

Methanol extract of Evodia lepta displays Syk/Src-targeted anti-inflammatory activity.

ETHNOPHARMACOLOGICAL RELEVANCE: Evodia lepta (Spreng.) Merr., in the Rutaceae family, is a medicinal plant traditionally used to treat inflammatory symptoms such as in meningitis and hepatitis. However, no study has systematically investigated its anti-inflammatory activities including its molecular mechanism. MATERIALS AND METHODS: The effects of a methanol extract from the roots Evodia lepta (El-ME) were evaluated using lipopolysaccharide (LPS)-treated RAW264.7 cells producing nitric oxide (NO) and prostaglandin E2 (PGE2), and an HCl/ethanol-induced mouse gastritis model. Target molecules were identified by analyzing the activation of transcription factors and their upstream kinases. RESULTS: El-ME reduced the production of NO and PGE2 from LPS-activated RAW264.7 cells in a dose-dependent manner. El-ME also ameliorated the gastritis symptoms of EtOH/HCl-treated mice. The extract suppressed production of mRNA for the inducible NO synthase (iNOS) and cyclooxygenase (COX)-2; the nuclear translocation of nuclear factor (NF)-κB; the phosphorylation of upstream kinases that activate NF-κB; and the kinase activities of Syk and Src. CONCLUSION: The anti-inflammatory effects of El-ME might be due to its suppression of Syk/Src and NF-κB. Considering the in vitro and in vivo efficacy of El-ME, Evodia lepta could be developed into an anti-inflammatory herbal remedy.

AP-1 pathway-targeted inhibition of inflammatory responses in LPS-treated macrophages and EtOH/HCl-treated stomach by Archidendron clypearia methanol extract.

ETHNOPHARMACOLOGICAL RELEVANCE: Archidendron clypearia Jack. (Fabaceae) is a representative ethnomedicinal herbal plant prescribed for various inflammatory diseases such as pharyngolaryngitis and tonsillitis. However, the pharmacology behind this plant's anti-inflammatory properties has not been fully understood. Therefore, in this study, the anti-inflammatory mechanism of a 95% methanol extract (Ac-ME) was explored. MATERIALS AND METHODS: The anti-inflammatory mechanism of Ac-ME on the AP-1 activation pathway, which plays a critical role in the production of prostaglandin (PG)E2 in RAW264.7 cells and peritoneal macrophages and in induction of acute gastritis caused by HCl/EtOH, was investigated using immunoblotting, immunoprecipitation analyses, and reporter gene activity assays. In particular, enzyme assays and HPLC analysis were employed to identify direct target enzymes of Ac-ME and to detect active chemical components from the plant extract. RESULTS: Ac-ME clearly reduced the nuclear levels of total and phospho-forms of c-Jun, FRA-1, and ATF-2. Consequently, this extract suppressed both the production of PGE2 in lipopolysaccharide (LPS)-activated RAW264.7 and peritoneal macrophage cells and PGE2-dependent induction of gastritis lesion in stomach under EtOH/HCl exposure. Analysis of AP-1 upstream signalling revealed that the AP-1 activation pathway consisting of IRAK1, TRAF6, TAK1, MKK3/6, and p38 was predominantly inhibited by Ac-ME. Similarly, this extract directly blocked the enzyme activity of IRAK1, indicating that this enzyme is an inhibitory target of Ac-ME and is involved in the suppression of the AP-1 pathway. HPLC analysis showed that quercetin, which inhibits PGE2 production, is an active component in Ac-ME. CONCLUSION: Ac-ME is an ethnomedicinal remedy with an IRAK1/p38/AP-1-targeted inhibitory property. Since AP-1 is a major inflammation-inducing transcription factor, the therapeutic potential of Ac-ME in other AP-1-mediated inflammatory symptoms will be further tested.

A rice orthologue of the ABA receptor, OsPYL/RCAR5, is a positive regulator of the ABA signal transduction pathway in seed germination and early seedling growth.

Abscisic acid (ABA) is a phytohormone that positively regulates seed dormancy and stress tolerance. PYL/RCARs were identified an intracellular ABA receptors regulating ABA-dependent gene expression in Arabidopsis thaliana. However, their function in monocot species has not been characterized yet. Herein, it is demonstrated that PYL/RCAR orthologues in Oryza sativa function as a positive regulator of the ABA signal transduction pathway. Transgenic rice plants expressing OsPYL/RCAR5, a PYL/RCAR orthologue of rice, were found to be hypersensitive to ABA during seed germination and early seedling growth. A rice ABA signalling unit composed of OsPYL/RCAR5, OsPP2C30, SAPK2, and OREB1 for ABA-dependent gene regulation was further identified, via interaction assays and a transient gene expression assay. Thus, a core signalling unit for ABA-responsive gene expression modulating seed germination and early seedling growth in rice has been unravelled. This study provides substantial contributions toward understanding the ABA signal transduction pathway in rice.

Classification of rice (Oryza sativa L. Japonica nipponbare) immunophilins (FKBPs, CYPs) and expression patterns under water stress.

BACKGROUND: FK506 binding proteins (FKBPs) and cyclophilins (CYPs) are abundant and ubiquitous proteins belonging to the peptidyl-prolyl cis/trans isomerase (PPIase) superfamily, which regulate much of metabolism through a chaperone or an isomerization of proline residues during protein folding. They are collectively referred to as immunophilin (IMM), being present in almost all cellular organs. In particular, a number of IMMs relate to environmental stresses. RESULTS: FKBP and CYP proteins in rice (Oryza sativa cv. Japonica) were identified and classified, and given the appropriate name for each IMM, considering the ortholog-relation with Arabidopsis and Chlamydomonas or molecular weight of the proteins. 29 FKBP and 27 CYP genes can putatively be identified in rice; among them, a number of genes can be putatively classified as orthologs of Arabidopsis IMMs. However, some genes were novel, did not match with those of Arabidopsis and Chlamydomonas, and several genes were paralogs by genetic duplication. Among 56 IMMs in rice, a significant number are regulated by salt and/or desiccation stress. In addition, their expression levels responding to the water-stress have been analyzed in different tissues, and some subcellular IMMs located by means of tagging with GFP protein. CONCLUSION: Like other green photosynthetic organisms such as Arabidopsis (23 FKBPs and 29 CYPs) and Chlamydomonas (23 FKBs and 26 CYNs), rice has the highest number of IMM genes among organisms reported so far, suggesting that the numbers relate closely to photosynthesis. Classification of the putative FKBPs and CYPs in rice provides the information about their evolutional/functional significance when comparisons are drawn with the relatively well studied genera, Arabidopsis and Chlamydomonas. In addition, many of the genes upregulated by water stress offer the possibility of manipulating the stress responses in rice.

C4 protein of Beet severe curly top virus is a pathomorphogenetic factor in Arabidopsis.

The Curtovirus C4 protein is required for symptom development during infection of Arabidopsis. Transgenic Arabidopsis plants expressing C4 from either Beet curly top virus or Beet severe curly top virus produced phenotypes that were similar to symptoms seen during infection with wild-type viruses. The pseudosymptoms caused by C4 protein alone were novel to transgenic Arabidopsis and included bumpy trichomes, severe enations, disorientation of vascular bundles and stomata, swelling, callus-like structure formation, and twisted siliques. C4 induced abnormal cell division and altered cell fate in a variety of tissues depending on the C4 expression level. C4 protein expression increased the expression levels of cell-cycle-related genes CYCs, CDKs and PCNA, and suppressed ICK1 and the retinoblastoma-related gene RBR1, resulting in activation of host cell division. These results suggest that the Curtovirus C4 proteins are involved actively in host cell-cycle regulation to recruit host factors for virus replication and symptom development.

Hydrophobically recovered and contact printed siloxane oligomers for general-purpose surface patterning.

Hydrophobic recovery of elastomeric polydimethylsiloxane (PDMS) has been well-known in various fields, such as microcontact printing (microCP), microfluidics, and electric insulation, etc., which has been believed to be due to the transfer of out-diffused siloxane oligomers in PDMS. The recovery phenomenon has been used to control surface energy of a substrate, due partly to its nanoscale thickness. In this work, we extend the use of recovered oligomers to a general-purpose surface patterning process, in combination with both dry and wet pattern transfer processes. The out-diffused and transfer-printed oligomers play exactly the same role of "ink" in the conventional microCP; thus, the present method can be termed as "inkless" microcontact printing (ImicroCP). Also, the detailed nature of recovered oligomers has been investigated, and they are found to have a molecular weight approximately 10 times larger than that of pristine, uncured PDMS oligomers. And the molecular weight distribution is very broad with a polydispersity index of approximately 15. Then, we present and discuss various aspects of the ImicroCP process, such as pattern transfer onto substrate via wet or dry etching, effect of process variables on printing results, minimum feature size achieved by the technique, repeated printing with the same stamp, and the generation of more complex patterns from simpler ones by applying multiple ImicroCP.

Overexpression of the downward leaf curling (DLC) gene from melon changes leaf morphology by controlling cell size and shape in Arabidopsis leaves.

A plant-specific gene was cloned from melon fruit. This gene was named downward leaf curling (CmDLC) based on the phenotype of transgenic Arabidopsis plants overexpressing the gene. This expression level of this gene was especially upregulated during melon fruit enlargement. Overexpression of CmDLC in Arabidopsis resulted in dwarfism and narrow, epinastically curled leaves. These phenotypes were found to be caused by a reduction in cell number and cell size on the adaxial and abaxial sides of the epidermis, with a greater reduction on the abaxial side of the leaves. These phenotypic characteristics, combined with the more wavy morphology of epidermal cells in overexpression lines, indicate that CmDLC overexpression affects cell elongation and cell morphology. To investigate intracellular protein localization, a CmDLC-GFP fusion protein was made and expressed in onion epidermal cells. This protein was observed to be preferentially localized close to the cell membrane. Thus, we report here a new plant-specific gene that is localized to the cell membrane and that controls leaf cell number, size and morphology.

Altered cell shapes, hyperplasia, and secondary growth in Arabidopsis caused by beet curly top geminivirus infection.

Arabidopsis Sei-O ecotype was found to be hypersusceptible to the BCTV-Logan strain in that it developed very severe symptoms, including severely deformed inflorescences with the callus-like structure, and accumulated high level of viral DNA. Microscopic studies of the BCTV-induced cell divisions demonstrated that the activation of cell divisions was preceded by the phloem disruption and the callus-like structure seemed to be originated from the cortex nearby disrupted phloem. We have further defined the callus-like structure formed by BCTV infection using molecular and histochemical analyses. Results indicate that BCTV infection causes the phloem disruption, following by cell enlargement and elongation in cortex and even epidermis. Finally, BCTV induced symptomatic secondary growth in cortex by de novo anticlinal and periclinal cell divisions. Expression of cdc2 and saur from BCTV-infected Arabidopsis correlates with symptom development. These results suggest a critical role of auxin in symptom development in the interactions between Arabidopsis and BCTV.