Molecular mechanism of somatic embryogenesis in paeonia ostii 'Fengdan' based on transcriptome analysis combined histomorphological observation and metabolite determination.

BACKGROUND: Tree peony (Paeonia sect. Moutan DC.) is a famous flower native to China with high ornamental, medicinal, and oil value. However, the low regeneration rate of callus is one of the main constraints for the establishment of a genetic transformation system in tree peony. By histomorphological observation, transcriptomic analysis and metabolite determination, we investigated the molecular mechanism of somatic embryogenesis after the establishment of a culture system and the induction of somatic embryo(SE) formation. RESULTS: We found that SE formation was successfully induced when cotyledons were used as explants. A total of 3185 differentially expressed genes were screened by comparative transcriptomic analysis of embryogenic callus (EC), SE, and non-embryogenic callus (NEC). Compared to NEC, the auxin synthesis-related genes GH3.6 and PCO2 were up-regulated, whereas cytokinin dehydrogenase (CKX6) and CYP450 family genes were down-regulated in somatic embryogenesis. In SE, the auxin content was significantly higher than the cytokinin content. The methyltransferase-related gene S-adenosylmethionine synthase (SAMS) and the flavonoid biosynthesis-related gene (ANS and F3'5'H) were down-regulated in somatic embryogenesis. The determination of flavonoids showed that rhoifolin and hyperoside had the highest content in SE. The results of transcriptome analysis were consistent with the relative expression of 8 candidate genes by quantitative polymerase chain reaction analysis. CONCLUSION: The results revealed that auxin and cytokinin may play a key role in 'Fengdan' somatic embryogenesis. The genes related to somatic embryogenesis were revealed, which has partly elucidated the molecular mechanism of somatic embryogenesis in 'Fengdan'.

Physiological and molecular response and tolerance of Macleaya cordata to lead toxicity.

BACKGROUND: Macleaya cordata is a traditional medicinal herb, and it has high tolerance and accumulation ability to heavy metals, which make it a good candidate species for studying phytoremediation. The objectives of this study were to investigate response and tolerance of M. cordata to lead (Pb) toxicity based on comparative analysis of transcriptome and proteome. RESULTS: In this study, the seedlings of M. cordata cultured in Hoagland solution were treated with 100 µmol·L- 1 Pb for 1 day (Pb 1d) or 7 days (Pb 7d), subsequently leaves of M. cordata were taken for the determination of Pb accumulation and hydrogen peroxide production (H2O2), meanwhile a total number of 223 significantly differentially expressed genes (DEGs) and 296 differentially expressed proteins (DEPs) were screened between control and Pb treatments. The results showed leaves of M. cordata had a special mechanism to maintain Pb at an appropriate level. Firstly, some DEGs were iron (Fe) deficiency-induced transporters, for example, genes of vacuolar iron transporter and three ABC transporter I family numbers were upregulated by Pb, which can maintain Fe homeostasis in cytoplasm or chloroplast. In addition, five genes of calcium (Ca2+) binding proteins were downregulated in Pb 1d, which may regulate cytoplasmic Ca2+ concentration and H2O2 signaling pathway. On the other hand, the cysteine synthase upregulated, glutathione S-transferase downregulated and glutathione reductase downregulated in Pb 7d can cause reduced glutathione accumulation and decrease Pb detoxification in leaves. Furthermore, DEPs of eight chlorophyll a/b binding proteins, five ATPases and eight ribosomal proteins can play a pivotal role on chloroplast turnover and ATP metabolism. CONCLUSIONS: Our results suggest that the proteins involved in Fe homeostasis and chloroplast turnover in mesophyll cells may play key roles in tolerance of M. cordata to Pb. This study offers some novel insights into Pb tolerance mechanism of plants, and the potential valuable for environmental remediation of this important medicinal plant.

Radiomics of Spinal Metastases Originating From Primary Nonsmall Cell Lung Cancer or Breast Cancer and Ability to Predict Epidermal Growth Factor Receptor Mutation/Ki-67 Levels.

OBJECTIVES: The aims of the study are to explore spinal magnetic resonance imaging (MRI)-based radiomics to differentiate spinal metastases from primary nonsmall cell lung cancer (NSCLC) or breast cancer (BC) and to further predict the epidermal growth factor receptor (EGFR) mutation and Ki-67 expression level. METHODS: In total, 268 patients with spinal metastases from primary NSCLC (n = 148) and BC (n = 120) were enrolled between January 2016 and December 2021. All patients underwent spinal contrast-enhanced T1-weighted MRI before treatment. Two- and 3-dimensional radiomics features were extracted from the spinal MRI images of each patient. The least absolute shrinkage and selection operator regression were applied to identify the most important features related to the origin of the metastasis and the EGFR mutation and Ki-67 level. Radiomics signatures (RSs) were established using the selected features and evaluated using receiver operating characteristic curve analysis. RESULTS: We identified 6, 5, and 4 features from spinal MRI to develop Ori-RS, EGFR-RS, and Ki-67-RS for predicting the metastatic origin, EGFR mutation, and Ki-67 level, respectively. The 3 RSs performed well in the training (area under the receiver operating characteristic curves: Ori-RS vs EGFR-RS vs Ki-67-RS, 0.890 vs 0.793 vs 0.798) and validation (area under the receiver operating characteristic curves: Ori-RS vs EGFR-RS vs Ki-67-RS, 0.881 vs 0.744 vs 0.738) cohorts. CONCLUSIONS: Our study demonstrated the value of spinal MRI-based radiomics for identifying the metastatic origin and evaluating the EGFR mutation status and Ki-67 level in patients with NSCLC and BC, respectively, which may have the potential to guide subsequent individual treatment planning.

Environmental effects of rural e-commerce: A case study of chemical fertilizer reduction in China.

The economic effects of rural e-commerce have been fully discussed by scholars, but few studies focus on the environmental effects of rural e-commerce. This study takes the reduced application of chemical fertilizer in China as an example. On the basis of constructing the corresponding theoretical framework, we take the promotion of Rural E-Commerce Demonstration County (REDC) policy as a quasi-natural experiment, using the county panel data from 2000 to 2020 and the multi-period difference-in-difference method to excavate the influence of rural e-commerce on the fertilizer reduction. Our results show that REDC policy reduces the amount of chemical fertilizer applied in the county by 21%, which is unexpected. Our findings passed a series of robustness tests, including dealing with selective bias, eliminating other policy interference in the same period and placebo test. Based on the heterogeneity analysis of grain production and marketing regions and informatization level, it is found that the effect of fertilizer reduction by rural e-commerce is more impressive in the major grain production areas and counties with low informatization level. According to the theoretical framework, we use the mediating effect model to verify the transmission mechanism of marginal income improvement, mechanization and labor transfer. Therefore, we believe that policy designers can use e-commerce to promote farmers to adopt the production strategies of reducing fertilizer application. The findings and recommendations of this study may be relevant to other countries with free trading markets and e-commerce platforms.

Anthocyanins accumulation analysis of correlated genes by metabolome and transcriptome in green and purple peppers (Capsicum annuum).

BACKGROUND: In order to clarify the the molecular mechanism of anthocyanin accumulation in green and purple fruits of pepper using metabolomics and transcriptomics,to identify different anthocyanin metabolites,and to analyze the differentially expressed genes involved in anthocyanin biosynthesis.. RESULTS: We analyzed the anthocyanin metabolome and transcriptome data of the fruits of 2 purple pepper and 1 green pepper. A total of 5 anthocyanin metabolites and 2224 differentially expressed genes were identified between the green and purple fruits of pepper. Among the 5 anthocyanin metabolites,delphin chloride was unique to purple pepper fruits,which is the mainly responsible for the purple fruit color of pepper. A total of 59 unigenes encoding 7 enzymes were identified as candidate genes involved in anthocyanin biosynthesis in pepper fruit. The six enzymes (PAL,C4H,CHI,DFR,ANS,UFGT) had higher expression levels except the F3H gene in purple compared with green fruits. In addition,seven transcription factors were also found in this study. These transcription factors may contribute to anthocyanin metabolite biosynthesis in the fruits of pepper. One of differentially expressed gene novel.2098 was founded. It was not annotated in NCBI. Though blast analysis we preliminarily considered that this gene related to MYB transcription factor and was involved in anthocyanin biosynthesis in pepper fruit. CONCLUSIONS: Overall, the results of this study provide useful information for understanding anthocyanin accumulation and the molecular mechanism of anthocyanin biosynthesis in peppers.

In Silico Prediction of Chemicals Binding to Aromatase with Machine Learning Methods.

Environmental chemicals may affect endocrine systems through multiple mechanisms, one of which is via effects on aromatase (also known as CYP19A1), an enzyme critical for maintaining the normal balance of estrogens and androgens in the body. Therefore, rapid and efficient identification of aromatase-related endocrine disrupting chemicals (EDCs) is important for toxicology and environment risk assessment. In this study, on the basis of the Tox21 10K compound library, in silico classification models for predicting aromatase binders/nonbinders were constructed by machine learning methods. To improve the prediction ability of the models, a combined classifier (CC) strategy that combines different independent machine learning methods was adopted. Performances of the models were measured by test and external validation sets containing 1336 and 216 chemicals, respectively. The best model was obtained with the MACCS (Molecular Access System) fingerprint and CC method, which exhibited an accuracy of 0.84 for the test set and 0.91 for the external validation set. Additionally, several representative substructures for characterizing aromatase binders, such as ketone, lactone, and nitrogen-containing derivatives, were identified using information gain and substructure frequency analysis. Our study provided a systematic assessment of chemicals binding to aromatase. The built models can be helpful to rapidly identify potential EDCs targeting aromatase.

Computational Investigation of Ligand Binding to the Peripheral Site in CYP3A4: Conformational Dynamics and Inhibitor Discovery.

Human cytochrome P450 3A4 (CYP3A4) is a major drug-metabolizing enzyme responsible for the metabolism of ∼50% of clinically used drugs and is often involved in drug-drug interactions. It exhibits atypical binding and kinetic behavior toward many ligands. Binding of ligands to CYP3A4 is a complex process. Recent studies from both crystallography and biochemistry suggested the existence of a peripheral ligand-binding site at the enzyme surface. However, the stability of the ligand bound at this peripheral site and the possibility of discovering new CYP3A4 ligands based on this site remain unclear. In this study, we employed a combination of molecular docking, multiparalleled molecular dynamics (MD) simulations, virtual screening, and experimental bioassay to investigate these issues. Our results revealed that the binding mode of progesterone (PGS), a substrate of CYP3A4, in the crystal structure was not stable and underwent a significant conformational change. Through Glide docking and MD refinement, it was found that PGS was able to stably bind at the peripheral site via contacts with Phe215, Phe219, Phe220, and Asp214. On the basis of the refined peripheral site, virtual screening was then performed against the Enamine database. A total of three compounds were finally found to have inhibitory activity against CYP3A4 in both human liver microsome and recombinant human CYP3A4 enzyme assays, one of which showed potent inhibitory activity with IC50 lower than 1 µM and two of which exhibited moderate inhibitory activity with IC50 values lower than 10 µM. The findings not only presented the dynamic behavior of PGS at the peripheral site but also demonstrated the first indication of discovering CYP3A4 inhibitors based on the peripheral site.

H2O2 Is Involved in the Metallothionein-Mediated Rice Tolerance to Copper and Cadmium Toxicity.

Cadmium (Cd) and excess copper (Cu) are toxic to plants, causing a wide range of deleterious effects including the formation of reactive oxygen species. Metallothioneins (MTs) may protect plant cells from heavy metal toxicity by chelating heavy metals via cysteine thiol groups. They may also function as antioxidants. The study investigated the relationship of H2O2 production and ricMT expression in rice radicles and rice suspension cells under Cu or Cd stress. The results showed that H2O2 production in the rice radicles increased before Cu-induced ricMT expression, and after Cd-induced ricMT expression. Rice suspension cells of sense- and antisense-ricMT transgenic lines were obtained by an Agrobacterium-mediated transformation. Overexpression of ricMT significantly decreased the death rate of rice cells, which was accompanied by blocked H2O2 accumulation in rice suspension cells subject to Cu and Cd stress. Our findings confirm that H2O2 is involved in the MT-mediated tolerance of Cu and Cd toxicity in rice.

Proteomic analysis of copper-binding proteins in excess copper-stressed rice roots by immobilized metal affinity chromatography and two-dimensional electrophoresis.

Copper (Cu) is an essential micronutrient required for plant growth and development. However, excess Cu can inactivate and disturb protein structure as a result of unavoidable binding to proteins. To understand better the mechanisms involved in Cu toxicity and tolerance in plants, we developed a new immobilized metal affinity chromatography (IMAC) method for the separation and isolation of Cu-binding proteins extracted from roots of rice seedling exposed to excess Cu. In our method, IDA-Sepharose or EDDS-Sepharose column (referred as pre-chromatography) and Cu-IDA-Sepharose column (referred as Cu-IMAC) were connected in tandem. Namely, protein samples were pre-chromatographed with IDA-Sepharose column to removal metal ions, then protein solution was flowed into Cu-IMAC column for enriching Cu-binding proteins in vitro. Compared with the control (Cu-IMAC without any pre-chromatography), IDA-Sepharose pre-chromatography method markedly increased yield of the Cu-IMAC-binding proteins, and number of protein spots and the abundance of 40 protein spots on two-dimensional electrophoresis (2-DE) gels. Thirteen protein spots randomly selected from 2-DE gel and 11 proteins were identified using MALDI-TOF-TOF MS. These putative Cu-binding proteins included those involved in antioxidant defense, carbohydrate metabolism, nucleic acid metabolism, protein folding and stabilization, protein transport and cell wall synthesis. Ten proteins contained one or more of nine putative metal-binding motifs reported by Smith et al. (J Proteome Res 3:834-840, 2004) and seven proteins contained one or two of top six motifs reported by Kung et al. (Proteomics 6:2746-2758, 2006). Results demonstrated that more proteins specifically bound with Cu-IMAC could be enriched through removal of metal ions from samples by IDA-Sepharose pre-chromatography. Further studies are needed on metal-binding characteristics of these proteins in vivo and the relationship between Cu ions and protein biological activities to fully understand the mechanisms of Cu tolerance and toxicity in plants.

iTRAQ proteome analysis reveals the underling mechanisms of foliage zinc-spraying to improve photosynthetic capacity and seed yields of Peaonia ostii 'Fengdan'.

Zinc (Zn) deficiency is a significant nutritional limitation to crop yield globally, particularly in calcareous soil environments. Tree peony of Peaonia ostii 'Fengdan' is regarded as an oil crop due to its seeds rich in alpha-linolenic acid, a beneficial compound for health promotion. However, low seed yield remains a primary challenge in attaining sufficient seed oil from tree peony. In this study, Zn fertilization was applied to soil or foliage of P. ostii 'Fengdan' in the growth period before fruit development. Our findings reveal that foliar Zn-spraying, as opposed to soil application, proves to be a more effective method for augmenting seed yield, Zn accumulation and photosynthetic capacity in 'Fengdan'. Comparative analyses of the leaf proteome of 'Fengdan' using iTRAQ profiling under foliar Zn-spraying identified 115 differentially expressed proteins (DEPs), including 36 upregulated proteins, which likely contribute to the observed increase in seed yields of 'Fengdan' caused by foliage Zn-spraying. Specifically, Zn2+ stimulation of phosphatidylinositol signaling initiates a cascade of metabolic regulations. Firstly, ATP synthesis promotes leaf photosynthetic capacity, facilitated by improved sucrose metabolism through upregulated pullulanase and 1,4-alpha-glucan-branching enzyme. Furthermore, lipid synthesis and transport are facilitated by upregulated lipoyl synthase and plastid lipid-associated proteins. Additionally, DEPs involved in secondary metabolism are upregulated in the production of various metabolites conducive to 'Fengdan' growth. Overall, our results demonstrate that foliage Zn-spraying enhances seed yield in P. ostii 'Fengdan' by elevating Zn content and secondary metabolite synthesis in leaves, thereby augmenting leaf photosynthetic capacity and lipid synthesis. This study provides an effective way to increase seed yield of tree peony by exogenous Zn application.

Acupressure: a possible therapeutic strategy for anxiety related to COVID-19: a meta-analysis of randomized controlled trials.

Background: From the end of 2019 to December 2023, the world grappled with the COVID-19 pandemic. The scope and ultimate repercussions of the pandemic on global health and well-being remained uncertain, ushering in a wave of fear, anxiety, and worry. This resulted in many individuals succumbing to fear and despair. Acupoint massage emerged as a safe and effective alternative therapy for anxiety relief. However, its efficacy was yet to be extensively backed by evidence-based medicine. This study aimed to enhance the clinical effectiveness of acupoint massage and extend its benefits to a wider population. It undertakes a systematic review of the existing randomized controlled trials (RCTs) assessing the impact of acupoint massage on anxiety treatment, discussing its potential benefits and implications. This research aims to furnish robust evidence supporting anxiety treatment strategies for patients afflicted with COVID-19 disease and spark new approaches to anxiety management. Objectives: This study evaluates the evidence derived from randomised controlled trials (RCTs), quantifies the impact of acupressure on anxiety manifestations within the general population, and proposes viable supplementary intervention strategies for managing COVID-19 related anxiety. Materials and methods: This review included RCTs published between February 2014 and July 2023, that compared the effects of acupressure with sham control in alleviating anxiety symptomatology as the outcome measure. The studies were sourced from the multiple databases, including CINAHL, EBM Reviews, Embase, Medline, PsycINFO, Scopus and Web of Science. A meta-analysis was performed on the eligible studies, and an overall effect size was computed specifically for the anxiety outcome. The Cochrane Collaboration Bias Risk Assessment Tool (RevMan V5.4) was employed to assess bias risk, data integration, meta-analysis, and subgroup analysis. The mean difference, standard mean deviation, and binary data were used to represent continuous outcomes. Results: Of 1,110 studies of potential relevance, 39 met the criteria for inclusion in the meta-analysis. The majority of the studies reported a positive effect of acupressure in assuaging anticipatory anxiety about treatment. Eighteen studies were evaluated using the STAI scale. The acupressure procedures were thoroughly documented, and studies exhibited a low risk of bias. The cumulative results of the 18 trials showcased a more substantial reduction in anxiety in the acupressure group compared to controls (SMD = -5.39, 95% CI -5.61 to -5.17, p < 0.01). A subsequent subgroup analysis, based on different interventions in the control group, demonstrated improvement in anxiety levels with sham acupressure in improving changes in anxiety levels (SMD -1.61, 95% CI: -2.34 to -0.87, p < 0.0001), and blank controls (SMD -0.92, 95% CI: -2.37 to 0.53, p = 0.22). Conclusion: In the clinical research of traditional Chinese medicine treatment of anxiety, acupressure demonstrated effectiveness in providing instant relief from anxiety related to multiple diseases with a medium effect size. Considering the increasing incidence of anxiety caused by long COVID, the widespread application of acupressure appears feasible. However, the results were inconsistent regarding improvements on physiological indicators, calling for more stringent reporting procedures, including allocation concealment, to solidify the findings.

Cloning and Expression Analysis of Key Enzyme Gene CoGPPS Involved in Iridoid Glycoside Synthesis in Cornus officinalis.

Cornus iridoid glycosides (CIGs), including loganin and morroniside, are the main active components of Cornus officinalis. As one of the key enzymes in the biosynthesis of CIGs, geranyl pyrophosphate synthase (GPPS) catalyzes the formation of geranyl pyrophosphate, which is the direct precursor of CIGs. In this study, the C. officinalis geranyl pyrophosphate synthase (CoGPPS) sequence was cloned from C. officinalis and analyzed. The cDNA sequence of the CoGPPS gene was 915 bp (GenBank No. OR725699). Phylogenetic analysis showed that CoGPPS was closely related to the GPPS sequence of Actinidia chinensis and Camellia sinensis, but relatively distantly related to Paeonia lactiflora and Tripterygium wilfordii. Results from the quantitative real-time PCR showed the spatiotemporal expression pattern of CoGPPS; that is, CoGPPS was specifically expressed in the fruits. Subcellular localization assay proved that CoGPPS was specifically found in chloroplasts. Loganin and morroniside contents in the tissues were detected by high-performance liquid chromatography, and both compounds were found to be at higher levels in the fruits than in leaves. Thus, this study laid the foundation for further studies on the synthetic pathway of CIGs.

Zinc Enhances Cadmium Accumulation in Shoots of Hyperaccumulator Solanum nigrum by Improving ATP-Dependent Transport and Alleviating Toxicity.

Solanum nigrum is a cadmium (Cd) and zinc (Zn) accumulator with potential for phytoextraction of soil contaminated with heavy metals. However, how Zn affects Cd accumulation in S. nigrum remains unclear. In this study, S. nigrum seedlings were treated with 100 µmol·L-1 Zn (Zn100), 100 µmol·L-1 Cd (Cd100), and the Zn and Cd combination (Zn100+Cd100) for 10 days under hydroponic culture. Compared with Cd100, the Cd content in stems, leaves, and xylem saps was 1.8, 1.6, and 1.3 times more than that in Zn100+Cd100, respectively. In addition, the production of reactive oxygen species in leaves was significantly upregulated in Cd100 compared with the control, and it was downregulated in Zn100. Comparative analyses of transcriptomes and proteomes were conducted with S. nigrum leaves. Differentially expressed genes (DEGs) were involved in Cd uptake, transport, and sequestration, and the upregulation of some transporter genes of Zn transporters (ZIPs), a natural resistance associated macrophage protein (Nramp1), a metal-nicotianamine transporter (YSL2), ATP-binding cassette transporters (ABCs), oligopeptide transporters (OPTs), and metallothionein (MTs) and glutathione S-transferase (GSTs) genes was higher in Zn100+Cd100 than in Cd100. In addition, differentially expressed proteins (DEPs) involved in electron transport chain, ATP, and chlorophyll biosynthesis, such as malate dehydrogenases (MDHs), ATPases, and chlorophyll a/b binding proteins, were mostly upregulated in Zn100. The results indicate that Zn supplement increases Cd accumulation and tolerance in S. nigrum by upregulating ATP-dependent Cd transport and sequestration pathways.

Characterization of the nuclear localization signal of the mouse TET3 protein.

DNA demethylation is associated with gene activation and is mediated by a family of ten-eleven translocation (TET) dioxygenase. The TET3 protein is a 1668-amino-acid DNA demethylase that is predicted to possess five nuclear localization signals (NLSs). In this paper, we used a series of green fluorescent protein-tagged and mutation constructs to identify a conserved NLS (KKRK) embedded between amino acid 1615 and 1618 of mouse TET3. The KKRK sequence facilitates the cytoplasmic protein's translocation into the nucleus. Additionally TET3 may be imported into the nucleus by importin-α and importin-ß.

Targeted editing of goat genome with modular-assembly zinc finger nucleases based on activity prediction by computational molecular modeling.

Zinc finger nuclease (ZFN) technology can mediate targeted genome modification to produce transgenic animals in a high-efficient and biological-safe way. Modular assembly is a rapid, convenient and open-source method for the synthesis of ZFNs. However, this biotechnology is hampered by multistep construction, low-efficiency editing and off-target cleavage. Here we synthesized and tested six pairs of three- or four-finger ZFNs to target one site in goat beta-lactoglobulin (BLG, a dominant allergen in goat milk) gene. Homology modeling was applied to build the structure model of ZFNs to predict their editing activities targeting at goat BLG gene. Goat fibroblast cells were transfected with plasmids that encoded ZFN pairs, and genomic DNA was isolated 72 h later for genome editing efficiency assay. The results of editing efficiency assay demonstrated that ZFNs with optimal interaction modes can edit goat BLG gene more efficiently, whereas ZFNs with unexpected interaction modes showed lower activities in editing BLG gene. We concluded that modular-assembly ZFNs can provide a rapid, public-available, and easy-to-practice platform for transgenic animal research and molecular modeling would help as a useful tool for ZFNs activity prediction.

Food security and overuse of agrochemicals: evidence from China's major grain-producing areas policy.

China's major grain-producing areas (MGPA) policy is the core policy to ensure national food security. While achieving long-term stable growth of grain production, assessing the impact of MGPA policy on agrochemical application has important practical significance in sustainable agricultural development and environmental protection. Based on panel data of 31 provinces in China from 1997 to 2020 and taking the MGPA policy introduced in 2004 as a quasi-natural experiment, we construct a difference-in-difference (DID) model to evaluate the overall impact and dynamic effect of MGPA policy. It is found that the MGPA policy do not exacerbate chemical overuse as a whole, but significantly reduce the fertilizer use by 11% and the pesticide use by 6%. Using the event study to decompose the policy effect year by year, we find that the MGPA policy significantly increased the fertilizer and pesticide use in a short period of time. Its influence on the application amount of two chemicals began to turn negative until the fourth and sixth years of the policy implementation and became more and more obvious. We conclude the intermediate paths of MGPA policy to change planting structure, deepen agricultural division of labor, and reduce the use of agrochemicals, which were verified by the intermediary effect model. From the perspective of provincial differences, MGPA policy reduced chemical use more in provinces with large output contribution and northern provinces. In addition, the MGPA policy has reduced the amount of fertilizer application in major rice-growing provinces, but not the amount of pesticide application. Our research can provide implications for other developing countries and emerging economies where agricultural production is highly dependent on chemicals and has green agricultural transition plans.

Response and Tolerance of Macleaya cordata to Excess Zinc Based on Transcriptome and Proteome Patterns.

Macleaya cordata is a dominant plant of mine tailings and a zinc (Zn) accumulator with high Zn tolerance. In this study, M. cordata seedlings cultured in Hoagland solution were treated with 200 µmol·L-1 of Zn for 1 day or 7 days, and then, their leaves were taken for a comparative analysis of the transcriptomes and proteomes between the leaves of the control and Zn treatments. Differentially expressed genes included those that were iron (Fe)-deficiency-induced, such as vacuolar iron transporter VIT, ABC transporter ABCI17 and ferric reduction oxidase FRO. Those genes were significantly upregulated by Zn and could be responsible for Zn transport in the leaves of M. cordata. Differentially expressed proteins, such as chlorophyll a/b-binding proteins, ATP-dependent protease, and vacuolar-type ATPase located on the tonoplast, were significantly upregulated by Zn and, thus, could be important in chlorophyll biosynthesis and cytoplasm pH stabilization. Moreover, the changes in Zn accumulation, the production of hydrogen peroxide, and the numbers of mesophyll cells in the leaves of M. cordata were consistent with the expression of the genes and proteins. Thus, the proteins involved in the homeostasis of Zn and Fe are hypothesized to be the keys to the tolerance and accumulation of Zn in M. cordata. Such mechanisms in M. cordata can suggest novel approaches to genetically engineering and biofortifying crops.

Gene Expression and Interaction Analysis of FsWRKY4 and FsMAPK3 in Forsythia suspensa.

Forsythia suspensa is a deciduous shrub that belongs to the family Myrtaceae, and its dried fruits are used as medicine. F. suspensa contains several secondary metabolites, which exert pharmacological effects. One of the main active components is forsythin, which exhibits free radical scavenging, antioxidant, anti-inflammatory, and anti-cancer effects. Mitogen-activated protein kinase (MAPKs) can increase the activity of WRKY family transcription factors in a phosphorylated manner, thereby increasing the content of secondary metabolites. However, the mechanism of interaction between MAPKs and WRKYs in F. suspensa remains unclear. In this study, we cloned the genes of FsWRKY4 and FsMAPK3, and performed a bioinformatics analysis. The expression patterns of FsWRKY4 and FsMAPK3 were analyzed in the different developmental stages of leaf and fruit from F. suspensa using real-time fluorescence quantitative PCR (qRT-PCR). Subcellular localization analysis of FsWRKY4 and FsMAPK3 proteins was performed using a laser scanning confocal microscope. The existence of interactions between FsWRKY4 and FsMPAK3 in vitro was verified by yeast two-hybridization. Results showed that the cDNA of FsWRKY4 (GenBank number: OR566682) and FsMAPK3 (GenBank number: OR566683) were 1587 and 522 bp, respectively. The expression of FsWRKY4 was higher in the leaves than in fruits, and the expression of FsMAPK3 was higher in fruits but lower in leaves. The subcellular localization results indicated that FsWRKY4 was localized in the nucleus and FsMAPK3 in the cytoplasm and nucleus. The prey vector pGADT7-FsWRKY4 and bait vector pGBKT7-FsMAPK3 were constructed and co-transferred into Y2H Glod yeast receptor cells. The results indicated that FsWRKY4 and FsMAPK3 proteins interact with each other in vitro. The preliminary study may provide a basis for more precise elucidation of the synthesis of secondary metabolites in F. suspensa.

Expression Analysis of CoHMGS in Cornus officinalis and Subcellular Localization of the Enzyme It Encodes.

Cornus officinalis is a perennial deciduous tree or shrub. Its mature fruits are extracted and used in Traditional Chinese Medicine, called Shanzhuyu. The characteristic active components of C. officinalis include loganin and morroniside, which belong to iridoid glycosides. 3-Hydroxy-3-methylglutaryl-CoA synthase (HMGS) is a key enzyme in the cytoplasmic mevalonate pathway providing the precursor molecules isopentenyl pyrophosphate and dimethylallyl pyrophosphate for isoprenoid biosynthesis such as sterols, triterpenes, and their derivatives such as iridoid glycosides. Different concentrations of methyl jasmonate (MeJA) and ethephon (ETH) solutions were sprayed on C. officinalis seedlings, and the effect of hormones on CoHMGS gene expression was detected by real-time fluorescence quantitative PCR. The quantitative real-time PCR results showed that 750 mg/L ETH treatment had the most significant induction effect on CoHMGS gene expression. The HPLC analysis of extracts revealed that the treatment could also significantly increase the content of morroniside and loganin in the leaves of C. officinalis. By use of a CoHMGS-green fluorescent protein (GFP) fusion construct for heterologous expression in tobacco, laser scanning confocal microscopy revealed a cytoplasmic localization. This preliminary study of the CoHMGS gene could prepare the ground for more precisely elucidating the synthesis of secondary metabolite in C. officinalis.

Oxidative Stress Response and Metal Transport in Roots of Macleaya cordata Exposed to Lead and Zinc.

Heavy metal pollution possesses potential hazards to plant, animal and human health, which has become the focus of recent attention. Hence, phytoremediation has been regarded as one of the most important remediation technologies for heavy-metal-contaminated soils. In this research, a dominant mine tailing plant, Macleaya cordata, was used as the experimental material to compare the metal transport and oxidative stress response in its roots under lead (Pb) and zinc (Zn) treatments. The result showed that Pb was mainly accumulated in the roots of M. cordata under the Pb treatment; less than 1% Pb was transported to the parts above. An analysis of the Zn content demonstrated a 39% accumulation in the shoots. The production of reactive oxygen species was detected using the in situ histological staining of roots, which showed that hydrogen peroxide in the root tips was observed to increase with the increase in both Pb and Zn concentrations. No significant superoxide anion changes were noted in the root tips under the Pb treatment. An analysis of the root enzyme activity showed that increase in NADPH oxidase activity can be responsible for the production of superoxide anions, subsequent the inhibition of root growth and decrease in antioxidant enzyme activities in the roots of M. cordata exposed to excess Zn. In total, this research provides evidence that the root of M. cordata has a high antioxidant capacity for Pb stress, so it can accumulate more Pb without oxidative damage. On the other hand, the Zn accumulated in the roots of M. cordata causes oxidative damage to the root tips, which can stimulate more Zn transport to the shoots to reduce the damage to the roots. This result will provide a basis for the application of M. cordata in the phytoremediation of soil polluted by Pb-Zn compounds.