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Applying chemical elicitors is considered a promising approach for controlling pests in the field. Our previous studies have shown that gibberellin (GA) signaling positively regulates the resistance of rice (Oryza sativa) to the brown planthopper (BPH) Nilaparvata lugens (Stal). Yet, whether the exogenous application of GAs can enhance the resistance of rice to BPH remains unknown. Here, we investigated the influence of exogenous GA3 on both defense responses in rice and BPH performance. We found that pretreating rice with GA3 decreased transcript levels of a mitogen-activated protein kinase (MAPK) and three WRKY transcription factors, as well as levels of BPH-elicited jasmonic acid (JA) and three phenolic acids but increased the release of ethylene. Moreover, GA3 treatment negatively affected the survival and development of BPH nymphs as well as the fecundity of BPH female adults. These findings suggest that GA3 promotes the resistance of rice to BPH and may, thus, be used to improve pest management in rice.

Synthetic chemical elicitors, so called plant strengtheners, can protect plants from pests and pathogens. Most plant strengtheners act by modifying defense signaling pathways, and little is known about other mechanisms by which they may increase plant resistance. Moreover, whether plant strengtheners that enhance insect resistance actually enhance crop yields is often unclear. Here, we uncover how a mechanism by which 4-fluorophenoxyacetic acid (4-FPA) protects cereals from piercing-sucking insects and thereby increases rice yield in the field. Four-FPA does not stimulate hormonal signaling, but modulates the production of peroxidases, H 2 O 2 , and flavonoids and directly triggers the formation of flavonoid polymers. The increased deposition of phenolic polymers in rice parenchyma cells of 4-FPA-treated plants is associated with a decreased capacity of the white-backed planthopper (WBPH) Sogatella furcifera to reach the plant phloem. We demonstrate that application of 4-PFA in the field enhances rice yield by reducing the abundance of, and damage caused by, insect pests. We demonstrate that 4-FPA also increases the resistance of other major cereals such as wheat and barley to piercing-sucking insect pests. This study unravels a mode of action by which plant strengtheners can suppress herbivores and increase crop yield. We postulate that this represents a conserved defense mechanism of plants against piercing-sucking insect pests, at least in cereals.

Long non-coding RNAs (lncRNAs) modulate a variety of cancerous biological processes, including the promotion of tumorigenicity in tumor parenchymal cells. However, there is a lack of studies assessing the regulation of lncRNAs in cancer-associated fibroblasts. In the present study, a novel lncRNA, TIRY, was found to act as a miRNA sponge and to downregulate miR-14 expression in oral squamous cell carcinoma (OSCC). Fluorescence in situ hybridization assay was used to evaluate TIRY expression in OSCC tissues. Survival analysis in a prospective cohort revealed a correlation between high TIRY expression and short progression-free survival. Subsequently, TIRY expression in cancer-associated fibroblasts and primary fibroblasts from adjacent normal (para-carcinoma) tissues was assessed using quantitative reverse transcription polymerase chain reaction. TIRY overexpression in cancer-associated fibroblasts isolated from OSCC tissues was induced by overexpressing the TIRY plasmid, and candidate microRNA expressions were assessed using quantitative real-time polymerase chain reaction. Moreover, the expression of proteins related to epithelial-to-mesenchymal transition (EMT) was determined; the proliferation, metastasis, and invasion of cancer cells co-cultured with TIRY-overexpressing cancer-associated fibroblasts were determined. We found significantly decreased miR-14 expression in cancer-associated fibroblast-derived exosomes and increased expression of EMT markers including transcription factors (Snail and FOXC2) and cellular scaffolding proteins (α-SMA, β-catenin, and FSP1). TIRY overexpression in cancer-associated fibroblasts activated the Wnt/β-catenin signaling pathway and promoted the invasion and metastasis of OSCC cells through miR-14 sponging based on cancer-associated exosome secretion. Our findings provide a novel molecular mechanism underlying the role of TIRY in cancer-associated fibroblasts in tumor biology; moreover, TIRY is a potential therapeutic target in OSCC. Impact statement This study demonstrated the novel lncRNA, TIRY, enhances epithelial-to-mesenchymal transition in cancer-associated fibroblasts and promotes the metastasis of tumor via miR-14 sponging in oral squamous cell carcinoma, and thus provide a novel molecular mechanism underlying the role of TIRY in CAFs in tumor biology and a potential target in OSCC. Further, the data showed that TIRY expression was negatively correlated with miR-14 transcription levels and was associated with poor prognosis in OSCC specimens. Therefore, TIRY may be a potential prognostic biomarker of overall survival and progression-free survival in OSCC. Moreover, TIRY adds to the understanding of regulatory mechanisms involved in CAFs and epithelial cancer cells in OSCC and may provide novel insights for further understanding tumor biology.

As the unique component of Dendrobium, dendrobine-type sesquiterpenoid alkaloids (DSAs) possess a variety of medicinal properties. It has been well documented that plant endophytes can in vitro synthesize secondary metabolites identical or similar to metabolites produced by their host plants. This study aimed to investigate the composition and distribution of endophytic bacteria of Dendrobium stems by Illumina MiSeq platform sequencing and cultivation-dependent methods and then to assess the potential for endophytic bacteria to produce DSAs. Results indicated that it was necessary to combine both cultivation-dependent and cultivation-independent methods to analyze the community structure of endophytic bacterial in plants comprehensively. The length of the Dendrobium stems influenced the endophytic bacterial community. The diversity and richness of endophytic bacteria in group J10_15cm of stems were the highest, which showed a significant difference from the other stem groups. However, there was no certain connection between the diversity and richness of endophytic bacteria and the content of dendrobine. It was most likely due to the influence of several specific endophytic bacteria genera, such as Sphingomonas and Rhodococcus. Athelia rolfsii, Myrothecium roridum, as pathogenic fungi, and Pectobacterium carotovorum subsp. actinidiae, as pathogenic bacteria of Dendrobium, were used to determine the antimicrobial activities. In these assays, six strains belonging to five genera showed antimicrobial activity against at least two phytopathogens. The strain BL-YJ10_15-29 (Paracoccus pueri THG-N2.35, 98.98%) showed the best antimicrobial activity against the three phytopathogens. In addition, 2 DSAs (6-hydroxydendrobine and nobilonine) were identified in the fermentation supernatant of the strain CM-YJ10_15-44 (Pseudomonas protegens CHA0, 99.24%), whereas the whole-genome analysis results further demonstrated that the precursors of the two DSAs [geranyl-PP and (E, E)-famesyl-PP] were synthesized mainly through the methyl-D-erythritol 4-phosphate pathway in this strain. This study provides new insight into the studies on the biosynthesis of DSAs and provides potential biocontrol bacteria.

In this work, a composite of microRNA-124-5p mimics (miR-124-5p) and gold nanoparticle (AuNP) aggregates was fabricated to combine the gene therapy and photothermal therapy for effective tumor medicine. The AuNP aggregates cross-linked by cystamine not only serve as photothermal therapeutic agents but are able to condense miR-124-5p as nanocarrier for gene delivery because of the coulomb interaction. The release of miR-124-5p could be initiated by the cleavage of cystamine when the nanocarrier enter the cytoplasm of tumor cells through endocytosis, where contains high concentration of glutathione (GSH). Moreover, the size of the AuNP aggregates did not change after the GSH-triggered miR-124-5p release because of the coinstantaneous disruption of disulfide bond and reformation of the thiol-gold bond, resulting in sustained photothermal property of the nanocarrier for tumor therapy. In vitro experiments showed that the miRNA@AuNAs (miR-124-5p) composite under near-infrared radiation performed great cytotoxicity to tumor cells, which is two and three times higher than the group of pure AuNP aggregates under near-infrared radiation and miRNA@AuNAs composite without near-infrared radiation, respectively. All experiment statistics show that the miRNA@AuNAs composite with combination of photothermal therapy and gene therapy has great potential for effective tumor treatment.

As an important global crop, the potato (Solanum tuberosum L.) contains the endotoxin solanine that leads to human poisoning and major economic losses. Poisoning symptoms and even acute poisoning may occur when the content of solanine in potatoes exceeds 200 mg/kg. In addition, potatoes are susceptible to some pathogenic bacteria, including Streptomyces scabies and Erwinia carotovora subsp. atroseptica (Van Hall) dye, which can cause potato scab and potato blackleg disease, respectively. In this study, 37 culturable endophytic bacteria strains were obtained from potato tubers based on the culture-dependent method. Results indicated that nine strains showed antimicrobial activity against at least one pathogen by antimicrobial activity screening and 23 strains showed inhibitory activity on solanine in potato tubers. Among them, strain P-NA2-14 (Bacillus megaterium NBRC 15308T, 99.31%) showed not only better antimicrobial activity against both the two indicator pathogens, but also the best inhibitory activity on solanine, which was proved to be a potential biocontrol bacterium. Meanwhile, the relationship between the distribution of the endophytic bacterial community and the content of solanine in potato tubers was studied by Illumina-based analysis, indicating that the distribution of the endophytic bacterial community was obviously influenced by the content of solanine. The results showed a new insight into the relationship between plant secondary metabolites and endophytic bacteria in potato tubers and provided potential new technical support for the biological control of potato storage.

Fresh kidney beans (Phaseolus vulgaris L.) are common green vegetable that are widely cultured and consumed worldwide. The benefits of fresh kidney beans are highly substantial, but at the same time, toxicity caused by phytohemagglutinin (PHA) has raised concerns. PHA from fresh kidney beans accounted for 40% of poisoning events induced by poisonous plants in China from 2004 to 2013. However, an understanding of PHA levels in fresh kidney beans remains elusive. An analysis method for PHA based on agglutination of PHA to erythrocyte cell was established. We investigated the effect of cultivar, bean part, maturity, and cooking method on PHA content in fresh kidney beans. We demonstrated significant differences in the distribution of PHA among various predominant, fresh Chinese kidney bean cultivars and parts. One major Chinese strain, Zihuayoudou, was found to contain the highest amount of PHA, which was abundant in fresh kidney bean seeds. Moreover, PHA concentrations were found to decrease with the maturity of the fresh product. Further, cooking methods had a significant effect on PHA levels in fresh kidney beans. PHA could be effectively removed when stir-frying for more than 18 min, or braising for more than 10 min. These findings provide insight into the PHA content of fresh kidney beans in China and will be helpful to guide food safety measures.

Lignin is one of the most important components of the plant cell wall, and the expression and transcriptional regulation of lignin biosynthesis-related genes have been studied widely in Arabidopsis and other plants. Citrus fruit juice sacs often undergo lignification, particularly during fruit ripening and storage periods; however, the underlying genetic mechanisms have been little investigated. In this study, we isolated and identified CsMYB330 and CsMYB308 transcription factors, and found that their expression levels are significantly altered during the lignification of citrus fruit juice sacs. We found that CsMYB330 and CsMYB308 can recognize and bind AC elements in the Cs4CL1 promoter and finely regulate expression of the Cs4CL1 gene. In this regulatory process, CsMYB330 was identified as a transcriptional activator, whereas CsMYB308 appears to be a transcriptional repressor. In addition, using a transient assay, we demonstrated that expression of the Cs4CL1 gene is significantly altered in fruit juice sacs overexpressing these two transcription factors. These results indicate that the transcription factors CsMYB330 and CsMYB308 play important roles in the lignification of citrus fruit juice sacs and provide novel insights into the transcriptional regulation associated with fruit juice sac lignification.

Purpose: To investigate polysaccharides (PEV) extracted from the aerial part of Verbena officinalis L. and their inhibitory effects on the invasion and metastasis of colorectal cancer (CRC) cells.Methods: PEV was extracted by water and the optimization of extraction conditions was performed using a Box-Benhnken design (BBD). The cell viability was evaluated by 4,5-dimethylthiazol-2-yl)2,5-diphenyltetrazolium bromide (MTT) assay. The effects of PEV on cell adhesion and invasion were evaluated by Transwell invasion, wound healing migration and adhesion assays in vitro. The effects of PEV on the expressions of matrix metalloproteinase-9 (MMP-9), mesenchymal-epithelial transition factor (C-met), E-cadherin (E-CAD), cyclooxygenase-2 (COX-2) and E-prostanoid 2 receptor (EP2) were investigated by western blot.Results: The BBD model was established successfully for the optimization of PEV extraction (p

Forty-four pre- and post-nature drying maize kernels were collected from North China Plain and assessed for fungi infection and mycotoxins contamination. The percentage of fungi infection was significantly higher in pre-nature drying samples than post-nature drying samples except for Fusariuim graminearum, which increases from 6.06% to 24.09%. Fusarium, Aspergillus, Alternaria and Trichoderma were main genera. Fusarium verticillioides (24.77%) and F. graminearum (15.08%) were predominant species, followed by Aspergillus niger (7.51%) and Aspergillus flavus (4.93%). FB1 and DON were the major mycotoxins presented in the samples, followed by ZEN. All samples showed FB1 ranging from 16.5 to 315.9 μg/kg. All post-nature drying maize kernels showed DON ranging from 5.8 to 9843.3 μg/kg, while 7 of 22 pre-nature drying samples contaminated with DON ranging from 50.7 to 776.6 μg/kg. The samples contaminated with ZEN in pre- and post-nature drying maize were 3, with the content ranging from 60.5 to 147.6 μg/kg and from 40.7 to 1056.8 μg/kg, respectively. Only 1 sample contaminated with AFB1 of 148.4 μg/kg. The occurrence of mycotoxins is highly in accordance with the incidence of the corresponding mycotoxin-producing fungi. This is the first comprehensive comparison of fungi infection and mycotoxins contamination between pre- and post-nature drying maize kernels.

The fates of clomazone, fomesafen, and quizalofop-p-ethyl and its metabolite quizalofop (acid) in soybean samples during tofu processing were systematically assessed. Residues were determined using ultra-performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS) after each processing step, including washing, soaking, grinding and filtering, cooking, coagulating, and squeezing. The pesticide distribution at each step of the process was studied, and pesticide processing factors were calculated. Differences in the pesticide residue levels were found at each processing step. Changes in pesticide residues in the tofu products was closely related to their physicochemical properties such as octanol-water partition coefficient (Kow), water solubility, and vapor pressure. The results showed that soaking prominently decreased fomesafen residues by 72.0%, as indicated by its high water-solubility and low log Kow. Grinding and filtering reduced pesticide residues by 88.8%–94.8%, mainly due to dilution or okara separation. The processing factors were generally

The effect of food processing on the level and fate of chiral pesticide residues in apple products has rarely been investigated. In this study, we used ultra-performance convergence chromatography coupled with triple quadrupole mass spectrometry to determine the content of the novel chiral acaricide cyflumetofen. The matrix-matched calibration lines were constructed for apple slices, juice, wine and vinegar, and the determination coefficients (r2) exceeded 0.9954. Acceptable average recoveries were within 81.1% to 119.9%, and the relative standard deviations (RSDs) ranged from 0.8% to 11.0%. Processing effectiveness is represented by the processing factor (PF). The results indicated that the PFs of different procedures (washing, peeling, enzymolysis, fermentation, among others.) were generally less than 1. The reduction of cyflumetofen enantiomers during fermentation was in accordance with first-order kinetics, and stereoselective behavior was observed. This study provides reliable references for the risk assessment of cyflumetofen in the processing of apple products.

Heteropoly acids were used as catalysts for cyclodehydration of various 1, n -diols. Cyclodehydration of butane-1,4-diol, pentane-1,5-diol and hexane-1,6-diol catalysed by H 3 PW 12 O 40 gave tetrahydrofuran, tetrahydropyran and oxepane, respectively. Cyclodehydration of diethylene glycol, triethylene glycol, diethylene glycol monomethyl ether and polyethylene glycol 200 catalysed by H 3 PW 12 O 40 gave 1,4-dioxane. In particular, cyclodehydration of hexane-1,6-diol gave an excellent yield of oxepane (80%). The selectivity exhibited by the H 3 PW 12 O 40 catalyst was even better than that exhibited by other reported catalyst systems for similar cyclodehydration reactions.

Ultra-performance convergence chromatography is an environmentally-friendly analytical method that uses dramatically reduced amounts of organic solvents. In addition, a robust and highly sensitive chiral separation method was developed for the novel chiral acaricide cyflumetofen by using ultra-performance convergence chromatography coupled with tandem mass spectrometry, which shows that stereoisomer recoveries determined for various apple parts ranged from 78.3% to 119.9%, with the relative standard deviations being lower than 14.0%. The half-lives of (−)-cyflumetofen and (+)-cyflumetofen obtained under 5-fold applied dosage equal to 22.13 and 22.23 days, respectively. For 1.5-fold applied dosage, the respective values were determined as 22.42 and 23.64 days, i.e., the degradation of (−)-cyflumetofen was insignificantly favored over that of its enantiomer. Importantly, cyflumetofen was unevenly distributed in apples, with its relative contents in apple peel, peduncle, and pomace equal to 50%, 22%, and 16%, respectively. The proposed method can be used to efficiently separate and quantify chiral pesticide with advantages of a shorter analysis time, greater sensitivity, and better environmental compatibility. Additionally, the consumption of apples with residue of cyflumetofen did not pose a health risk to the population if the cyflumetofen applied under satisfactory agricultural practices after the long-term dietary risk assessment.

Genetically modified (GM) rice KMD1, TT51-1, and KF6 are three of the most well known transgenic Bt rice lines in China. A rapid and sensitive molecular assay for risk assessment of GM rice is needed. Polymerase chain reaction (PCR), currently the most common method for detecting genetically modified organisms, requires temperature cycling and relatively complex procedures. Here we developed a visual and rapid loop-mediated isothermal amplification (LAMP) method to amplify three GM rice event-specific junction sequences. Target DNA was amplified and visualized by two indicators (SYBR green or hydroxy naphthol blue [HNB]) within 60 min at an isothermal temperature of 63 °C. Different kinds of plants were selected to ensure the specificity of detection and the results of the non-target samples were negative, indicating that the primer sets for the three GM rice varieties had good levels of specificity. The sensitivity of LAMP, with detection limits at low concentration levels (0.01%–0.005% GM), was 10- to 100-fold greater than that of conventional PCR. Additionally, the LAMP assay coupled with an indicator (SYBR green or HNB) facilitated analysis. These findings revealed that the rapid detection method was suitable as a simple field-based test to determine the status of GM crops.

An enantioselective method is presented for the determination of isocarbophos in soil by liquid chromatography coupled with tandem mass spectrometry. The pesticide residues in soil samples were extracted with acetonitrile, and complete enantioseparation was obtained on an amylose tris(3,5-dimethylphenylcarbamate) chiral column using acetonitrile/2 mM ammonium acetate solution containing 0.1% formic acid (60:40, v/v) as the mobile phase. The absolute configuration of isocarbophos enantiomers was determined by the combination of experimental and calculated electronic circular dichroism spectra. The method was utilized to investigate the degradation of isocarbophos in soils (Changchun, Hangzhou, and Zhengzhou) under sterilized or native conditions. Isocarbophos enantiomers were configurationally stable in the selected soils, and the pesticide degradation was not enantioselective in the sterilized condition. The degradation behavior of rac-isocarbophos was different under native conditions, with no enantioselectivity in the Changchun soil and with the S-(+)-isocarbophos enriched in the Hangzhou and Zhengzhou soils.

A sensitive gas chromatographic–triple quadrupole mass spectrometric (GC–QqQ MS) analytical method, for the determination of zearalenone and its five derivatives in edible vegetable oil, was developed. After the vegetable oil samples were prepared using gel permeation chromatography, the eluent was collected, evaporated and dried with nitrogen gas. The residue was silylated with N,O-bis-trimethylsilyltrifluoroacetamide, containing 1% trimethylchlorosilane. GC–QqQ MS was performed in the reaction-monitoring mode to confirm and quantify mycotoxins in vegetable oil. The limits of quantitation were 0.03–0.2 μg kg−1 for the six mycotoxins. The average recoveries, measured at 2, 20 and 200 μg kg−1, were in the range 80.3–96.5%. Zearalenone was detected in the range 5.2–184.6 μg kg−1 in nine maize oils and at 40.7 μg kg−1 in a rapeseed oil from the local market.