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The cyclopropanation of alkenes through the transition-metal-catalyzed decomposition of diazo compounds is a powerful and straightforward strategy to produce cyclopropanes. Nevertheless, the appeal of further application of this strategy is tempered by the potentially explosive nature of the diazo substrates. Therefore, it is highly desirable to develop sustainable and operationally safe surrogates for diazo compounds. In this Synpacts article, we discuss recent advances on the cyclopropane syntheses through the catalytic cyclopropanation of alkenes and metal carbenes generated in situ from nondiazo precursors as well as highlight our recent progress on the unprecedented molybdenum-catalyzed deoxygenative cyclopropanation reaction of 1,2-dicarbonyl or monocarbonyl compounds.

Many integral membrane proteins might act as indispensable coordinators in specific functional microdomains to maintain the normal operation of known receptors, such as Notch. Gm364 is a multi-pass transmembrane protein that has been screened as a potential female fertility factor. However, there have been no reports to date about its function in female fertility. Here, we found that global knockout of Gm364 decreased the numbers of primordial follicles and growing follicles, impaired oocyte quality as indicated by increased ROS and γ-H2AX, decreased mitochondrial membrane potential, decreased oocyte maturation, and increased aneuploidy. Mechanistically, Gm364 directly binds and anchors MIB2, a ubiquitin ligase, on the membrane. Subsequently, membrane MIB2 ubiquitinates and activates DLL3. Next, the activated DLL3 binds and activates Notch2, which is subsequently cleaved within the cytoplasm to produce NICD2, the intracellular active domain of Notch2. Finally, NICD2 can directly activate AKT within the cytoplasm to regulate oocyte meiosis and quality.

Various abiotic stressors, particularly drought stress, affect plant growth and yield. Zinc finger proteins play an important role in plant abiotic stress tolerance. Here, we isolated the apple MdZAT10 gene, a C2H2-type zinc finger protein, which is a homolog of Arabidopsis STZ/ZAT10. MdZAT10 was localized to the nucleus and highly expressed in leaves and fruit. Promoter analysis showed that MdZAT10 contained several response elements and the transcription level of MdZAT10 was induced by abiotic stress and hormone treatments. MdZAT10 was responsive to drought treatment both at the transcriptional and post-translational levels. MdZAT10-overexpressing apple calli decreased the expression level of MdAPX2 and increased sensitivity to PEG 6000 treatment. Moreover, ectopically expressed MdZAT10 in Arabidopsis reduced the tolerance to drought stress, and exhibited higher water loss, higher malondialdehyde (MDA) content and higher reactive oxygen species (ROS) accumulation under drought stress. In addition, MdZAT10 reduced the sensitivity to abscisic acid in apple. Ectopically expressed MdZAT10 in Arabidopsis promoted seed germination and seedling growth. These results indicate that MdZAT10 plays a negative regulator in the drought resistance, which can provide theoretical basis for further molecular mechanism research.

Designing and modulating the local structure of metal sites is the key to gain the unique selectivity and high activity of single metal site catalysts. Herein, we report strain engineering of curved single atomic iron-nitrogen sites to boost electrocatalytic activity. First, a helical carbon structure with abundant high-curvature surface is realized by carbonization of helical polypyrrole that is templated from self-assembled chiral surfactants. The high-curvature surface introduces compressive strain on the supported Fe-N4 sites. Consequently, the curved Fe-N4 sites with 1.5 % compressed Fe-N bonds exhibit downshifted d-band center than the planar sites. Such a change can weaken the bonding strength between the oxygenated intermediates and metal sites, resulting a much smaller energy barrier for oxygen reduction. Catalytic tests further demonstrate that a kinetic current density of 7.922 mA cm-2 at 0.9 V vs. RHE is obtained in alkaline media for curved Fe-N4 sites, which is 31 times higher than that for planar ones. Our findings shed light on modulating the local three-dimensional structure of single metal sites and boosting the catalytic activity via strain engineering.

Electrophilic fluorophosphonium triflates bearing pyridyl (3[OTf]) or imidazolyl (4[OTf])-substituents act as intramolecular frustrated Lewis pairs (FLPs) and reversibly form 1 : 1 adducts with CO2 (5+ and 6+ ). An unusual and labile spirocyclic tetrahedral intermediate (72+ ) is observed in CO2 -pressurized (0.5-2.0 bar) solutions of cation 4+ at low temperatures, as demonstrated by variable-temperature NMR studies, which were confirmed crystallographically. In addition, cations 3+ and 4+ actively bind carbonyls, nitriles and acetylenes by 1,3-dipolar cycloaddition, as shown by selected examples.

Titanium (Ti) is a widely used metallic biomaterial in developing orthopedic implants or devices, but it is often encountered with a poor osteogenic response. In this study, the authors report the surface modification of Ti with cobalt (Co)-containing titanium dioxide (TiO2) coatings by plasma oxidation technique in order to enhance its cellular response. The results were compared between unmodified and surface modified Ti. The scanning electron microscopy (SEM) analysis showed that the surface coating was homogenous and porous throughout the test specimen. Indeed, the energy-dispersive X-ray spectrometry (EDS) analysis showed that the cobalt was evenly distributed on the Ti surface. It was also observed from the preliminary cell culture studies that the surfacemodified Ti has excellent cell compatibility and has promoted the adhesion and proliferation of osteoblasts when compared to the unmodified Ti. The present study clearly demonstrated that the Co-containing plasma electrolytic oxidation is an efficient technique for the surface modification of Ti in order to promote its osteogenic response.

A homologous gene of strigolactones repressor protein gene SMXL7/D53, MdSMXL8.2 (GenBank accession No.: MD07G1222400), was cloned from ‘Royal Gala’ apple (Malus × domestica Borkh.) in this study. The sequence analysis revealed that the length of this gene was 3 243 bp, which encoded 1 080 amino acids, and had a protein molecular mass of ∼110 kD. The phylogenetic tree analysis indicated that the MdSMXL8.2 exhibited the highest sequence similarity with Arabidopsis AtSMXL7. The protein conserved domain analysis revealed that the MdSMXL8.2 contained two ClpA domains. The prediction of the secondary and tertiary structures of the MdSMXL8.2 indicated that it contained 34.54% α helix, 3.43% β-sheet, and 11.76% extended chain. The in-silico analysis suggested that the promoter sequence of MdSMXL8.2 contained several typical cis-acting elements, including abscisic acid (ABA), gibberellin (GA), ethylene, auxin, jasmonic acid (JA), salicylic acid (SA), drought, and heat stress-responsive elements. Quantitative real-time (qRT)-PCR analyses revealed that MdSMXL8.2 was expressed in different apple tissues, with the highest transcript level found in the stem. The expression of MdSMXL8.2 was significantly induced by exogenous ABA, PEG and mannitol, while exogenous NaCl significantly inhibited MdSMXL8.2 expression. The growing status of MdSMXL8.2-overexpressed Orin apple callus was worse than the wild type (WT) after NaCl treatment and had a higher malondialdehyde (MDA) content and relative conductance (REC). Additionally, MdSMXL8.2-overexpressed Arabidopsis exhibited shorter root length and a reduction in fresh weight under salt stress, indicating that MdSMXL8.2 negatively regulated salt tolerance in apples.

Herein, the catalytic properties and reaction mechanisms of the 3d, 4d, and 5d transition metals embedded in 2D rectangular tetracyanoquinodimethane (TM-rTCNQ) monolayers as single-atom catalysts (SACs) for the electrocatalytic N2 reduction reaction (NRR) were systematically investigated, using first-principles calculations. A series of high-throughput screenings were carried out on 30 TM-rTCNQ monolayers, and all possible NRR pathways were explored. Three TM-rTCNQ (TM = Mo, Tc, and W) SACs were selected as promising new NRR catalyst candidates because of their high structural stability and good catalytic performance (low onset potential and high selectivity). Our results show that the Mo-rTCNQ monolayer can catalyze NRR through a distal mechanism with an onset potential of -0.48 V. Surprisingly, the NH3 desorption energy on the Mo-rTCNQ monolayer is only 0.29 eV, the lowest one reported in the literature so far, which makes the Mo-rTCNQ monolayer a good NRR catalyst candidate. In-depth research studies on the structures of N2-TM-rTCNQ (TM = Mo, Tc, and W) found that strong adsorption and activation performance of TM-rTCNQ for N2 may be due to the strong charge transfer and orbital hybridization between the TM-rTCNQ catalyst and the N2 molecules. Our work provides new ideas for achieving N2 fixation under environmental conditions.

The transition-metal-catalyzed cyclopropanation of alkenes by the decomposition of diazo compounds is a powerful and straightforward strategy to produce cyclopropanes, but is tempered by the potentially explosive nature of diazo substrates. Herein we report the Mo-catalyzed regiospecific deoxygenative cyclopropanation of readily available and bench-stable 1,2-dicarbonyl compounds, in which one of the two carbonyl groups acts as a carbene equivalent upon deoxygenation and engages in the subsequent cyclopropanation process. The use of a commercially available Mo catalyst afforded an array of valuable cyclopropanes with exclusive regioselectivity in up to 90 % yield. The synthetic utility of this method was further demonstrated by gram-scale syntheses, late-stage functionalization, and the cyclopropanation of a simple monocarbonyl compound. Preliminary mechanistic studies suggest that phosphine (or silane) acts as both a mild reductant and a good oxygen acceptor that efficiently regenerates the catalytically active Mo catalyst through reduction of the Mo-oxo complexes.

MdBZR1 directly binds to the promoter of MdABI5 and suppresses its expression to mediate ABA response. The plant hormones brassinosteroids (BRs) and abscisic acid (ABA) antagonistically regulate various aspects of plant growth and development. However, the association between BR and ABA signaling is less clear. Here, we identified MdBZR1 in apple (Malus domestica) and demonstrated that it was activated by BRs and could respond to ABA treatment. Overexpression of MdBZR1 in apple calli and Arabidopsis reduced ABA-hypersensitive phenotypes, suggesting that MdBZR1 negatively regulates ABA signaling. Subsequently, we found that MdBZR1 directly bound to the promoter region of MdABI5 and suppressed its expression. MdABI5 was significantly induced by ABA treatment. And overexpression of MdABI5 in apple calli increased sensitivity to ABA. Ectopic expression of MdABI5 in Arabidopsis inhibited seed germination and seedling growth. In addition, overexpression of MdBZR1 partially attenuated MdABI5-mediated ABA sensitivity. Taken together, our data indicate that MdBZR1 directly binds to the promoter of MdABI5 and suppresses its expression to antagonistically mediate ABA response. Our work contributes to the functional studies of BZR1 and further broadens the insight into the between BR and ABA signaling.

Jasmonate (JA) induces the biosynthesis of anthocyanin and proanthocyanidin. MdMYB9 is essential for modulating the accumulation of both anthocyanin and proanthocyanidin in apple, but the molecular mechanism for induction of anthocyanin and proanthocyanidin biosynthesis by JA is unclear. In this study, we discovered an apple telomere-binding protein (MdTRB1) to be the interacting protein of MdMYB9. A series of biological assays showed that MdTRB1 acted as a positive modulator of anthocyanin and proanthocyanidin accumulation, and is dependent on MdMYB9. MdTRB1 interacted with MdMYB9 and enhanced the activation activity of MdMYB9 to its downstream genes. In addition, we found that the JA signaling repressor MdJAZ1 interacted with MdTRB1 and interfered with the interaction between MdTRB1 and MdMYB9, therefore negatively modulating MdTRB1-promoted biosynthesis of anthocyanin and proanthocyanidin. These results show that the JAZ1-TRB1-MYB9 module dynamically modulates JA-mediated accumulation of anthocyanin and proanthocyanidin. Taken together, our data further expand the functional study of TRB1 and provide insights for further studies of the modulation of anthocyanin and proanthocyanidin biosynthesis by JA.

A novel coordination polymer containing Mn(II) ions as nodes was prepared by the hydrothermal method, and its chemical formula is {[Mn2(L)(hfpd)(H2O)]·1.75H2O}n (1) (L = 4,4′-bis(imidazol-1-yl)-biphenyl and H4hfpd = 4,4′-(hexafluoroisopropylidene)diphthalic acid). It was then used for evaluation the relationship with the Endometriosis (EMs). The activation for the estrogen receptor relative expression on the surface of endometrial cell was detected through the real time RT-PCR, and the results showed that complex 1 could obviously decreased the estrogen receptor over expression on the endometrial cell surface dose dependently. The immune function of the macrophages under the endometrial cells were determined by Western blot, the data indicated that complex 1 exerts the excellent treatment activity via activating the autophagy in macrophages. Molecular docking simulations reveal that the origin of the biological activity is from the carboxyl functional groups on the complex.

Iron (Fe) is an essential element for plant growth, development, and metabolism. Due to its lack of solubility and low bioavailability in soil, Fe levels are usually far below the optimum amount for most plants' growth and development. In apple production, excessive use of nitrogen fertilizer may cause iron chlorosis symptoms in the newly growing leaves, but the regulatory mechanisms underlying this phenomenon are unclear. In this study, low nitrate (NO3 - , LN) application alleviated the symptoms of Fe deficiency and promoted lower rhizosphere pH, which was beneficial for root Fe acquisition. At the same time, LN treatment increased citrate and abscisic acid (ABA) accumulation in roots, which promoted Fe transport from root to shoot and maintained Fe homeostasis. Moreover, qRT-PCR analysis showed that nitrate application caused differential expression of genes related to Fe uptake and transport, as well as transcriptional regulators. In summary, our data reveal that low nitrate alleviated Fe deficiency through multiple pathways, demonstrating a new option for minimizing Fe deficiency by regulating the balance between nutrients. This article is protected by copyright. All rights reserved.

Abscisic acid (ABA) induces chlorophyll degradation and leaf senescence; however, the molecular mechanism remains poorly understood, especially in woody plants. In this study, we found that MdABI5 plays an essential role in the regulation of ABA-triggered leaf senescence in Malus domestica (apple). Through yeast screening, three transcription factors, MdBBX22, MdWRKY40 and MdbZIP44, were found to interact directly with MdABI5 in vitro and in vivo. Physiological and biochemical assays showed that MdBBX22 delayed leaf senescence in two pathways. First, MdBBX22 interacted with MdABI5 to inhibit the transcriptional activity of MdABI5 on the chlorophyll catabolic genes MdNYE1 and MdNYC1, thus negatively regulating chlorophyll degradation and leaf senescence. Second, MdBBX22 interacted with MdHY5 to interfere with the transcriptional activation of MdHY5 on MdABI5, thereby inhibiting the expression of MdABI5, which also contributed to the delay of leaf senescence. MdWRKY40 and MdbZIP44 were identified as positive regulators of leaf senescence. They accelerated MdABI5-promoted leaf senescence through the same regulatory pathways, i.e., interacting with MdABI5 to enhance the transcriptional activity of MdABI5 on MdNYE1 and MdNYC1. Taken together, our results suggest that MdABI5 works with its positive or negative interaction partners to regulate ABA-mediated leaf senescence in apple, in which it acts as a core regulator. The antagonistic regulation pathways ensure that plants respond to external stresses flexibly and efficiently. Our results provide a concept for further study on the regulation mechanisms of leaf senescence.

Fluorescent coatings are a kind of emerging light quality regulation material that can improve plant light utilization efficiency through easy manipulation at a low price. Compared with the scheme of fluorescent nanomaterials alone or those physically dispersed in polymeric materials for photosynthesis enhancement, fluorescent polymeric coatings (FPCs) originating from the covalent copolymerization of nanomaterial monomers can function stably and continuously, circumventing the high-cost manipulation of continuous leaf-spraying or hydroponics of the previous scheme in practical applications. Herein, we developed a kind of FPCs consisting of UV-to-blue light-converting nitrogen-doped carbon dots (N-CDs) as the fluorescent monomer to induce the copolymerization of N-CDs and tannic acid (TA). In the FPCs, N-CDs and TA are covalently cross-linked together. The fluorescent ability of N-CDs and the strong adhesion of TA are integrated organically to the whole to endow FPCs with excellent properties of prolonged fluorescence capacity, rain-erosion resistance and stability. After spraying FPCs on tomato leaves grown under the full spectrum, both the chlorophyll content of the leaves and effective photochemical efficiency were increased significantly, and the growth rate was promoted with 38.3% and 43.2% enhancement in the dry and fresh weight. We also analyzed the human cytotoxicity of the coating and the toxicological experiments showed that the coating did not affect the proliferation of human cells.

The in situ electrophilic fluorination of phosphanes with commercially available bench-stable N-fluorobenzenesulfonimide (NFSI), followed by subsequent methylation of the [N(PhSO2)2]− anion with MeOTf yields a family of electrophilic fluorophosphonium cations as triflate salts. Most of these fluorophosphonium triflate salts are remarkably Lewis acidic and form isolable adducts in stoichiometric reactions with suitable donors such as N,N-dimethylformamide (DMF). Furthermore, their catalytic capabilities were tested in the transformation of formamides into N-sulfonyl formamidines in the reaction with Na[N(SO2Ph)2] and the proposed mechanism is validated by DFT calculations.

Background: AMP-activated protein kinase (AMPK) activators can improve inflammatory pain and neuropathic pain. Inflammation translocate signal transducers and activators of transcription 3 (STAT3) to the nuclei of activated macrophages, and STAT3 phosphorylation promotes the expression of inducible nitric oxide synthetase (iNOS). In this study, we determined whether AMPK activation alleviate inflammatory pain via STAT3 nuclear translocation and phosphorylation. Methods: Immunoblotting was used to measure the expression of p-AMPK, and iNOS. Immunoblotting and immunofluorescence were used to detect the nuclear translocation of p-STAT3(Ser727) and STAT3 in macrophages of local inflammatory tissues. Flow cytometry was used to measure reactive oxygen species (ROS) accumulation and mitochondrial damage.Results: AMPK activation with AICAR significantly alleviated pain hypersensitivity and inhibited the expression of iNOS in complete Freund's adjust (CFA)-induced inflamed skin tissues. CFA caused nuclear translocation of STAT3 and p-STAT3(Ser727) in macrophages of inflamed skin tissues. AICAR inhibited nuclear translocation of STAT3 and p-STAT3(Ser727) and promoted the phosphorylation of STAT3(Ser727) in the cytoplasm of macrophages. AICAR also inhibited the expression of iNOS and nuclear translocation of STAT3 and p-STAT3(Ser727), and promoted the phosphorylation of STAT3(Ser727) in NR8383 macrophages treated with CFA. AMPK activation also inhibited the ROS generation and the mitochondrial damage of NR8383 macrophages caused by CFA. In addition, transfection of STAT3 S727D decreased ROS and alleviated mitochondrial damage.Conclusions: Activation of AMPK attenuates inflammatory pain and suppresses STAT3 nuclear translocation and phosphorylation of STAT3(Ser727) in macrophages, resulting in reduced iNOS. Activation of AMPK also promotes phosphorylation of STAT3(Ser727) in the cytoplasm of macrophages to alleviate ROS accumulation and mitochondrial damage associated with inflammation.

MYB transcription factors (TFs) participate in many biological processes. However, the molecular mechanisms by which MYB TFs affect plant resistance to apple ring rot remain poorly understood. Here, the R2R3-MYB gene MdMYB73 was cloned from "Royal Gala" apples and functionally characterized as a positive regulator of the defense response to Botryosphaeria dothidea. qRT-PCR and GUS staining demonstrated that MdMYB73 was strongly induced in apple fruits and transgenic calli after inoculation with B. dothidea. MdMYB73 overexpression improved resistance to B. dothidea in apple calli and fruits, while MdMYB73 suppression weakened. Increased resistance to B. dothidea was also observed in MdMYB73-expressing Arabidopsis thaliana. Interestingly, salicylic acid (SA) contents and the expression levels of genes related with SA synthesis and signaling were greater in MdMYB73-overexpressing plant materials compared to wild-type controls after inoculation, suggesting that MdMYB73 might enhance resistance to B. dothidea via the SA pathway. Finally, we discovered that MdMYB73 interacts with MdWRKY31, a positive regulator of B. dothidea. Together, MdWRKY31 and MdMYB73 enhanced B. dothidea resistance in apples. Our results clarify the mechanisms by which MdMYB73 improves resistance to B. dothidea and suggest that resistance may be affected by regulating the SA pathway.

Post-translational modification of proteins mediated by SIZ1, a small ubiquitin-like modifier (SUMO) E3 ligase, regulates multiple biological processes in plants. However, its role in the regulation of lateral root formation remains unclear. Here, we demonstrate that the apple SUMO E3 ligase MdSIZ1 promotes lateral root formation. Using a yeast-two-hybrid (Y2H) system, the auxin response factor MdARF8 was screened out as a protein-protein interaction partner of the SUMO-conjugating E2 enzyme MdSCE1, indicating that MdARF8 may be a substrate for MdSIZ1. The interaction between MdARF8 and MdSCE1 was confirmed by pull-down, Y2H and Co-immunoprecipitation assays. MdSIZ1 enhanced the conjugating enzyme activity of MdSCE1 to form a MdSCE1-MdSIZ1-MdARF8 complex, thereby facilitating SUMO modification. We identified two arginine substitution mutations at K342 and K380 in MdARF8 that blocked MdSIZ1-mediated SUMOylation, indicating that K342 and K380 are the principal SUMOylation sites of the MdARF8 protein. Moreover, MdARF8 promoted lateral root formation in transgenic apple plants, and the phenotype of reduced lateral roots in the Arabidopsis siz1-2 mutant was restored in siz1-2/MdARF8 complementary plants. Our findings reveal an important role for sumoylation in the regulation of lateral root formation in plants.

Mammalian female meiosis must be tightly regulated to produce high-quality mature oocytes for subsequent regular fertilization and healthy live birth of the next generation. GTPases control many important signal pathways involved in diverse cellular activities. ADP-ribosylation factor family members (Arfs) in mice possess GTPase activities, and some members have been found to function in meiosis. However, whether other Arfs play a role in meiosis is unknown. In this study, we found that Arl2 and Arf5 are the richest among Arfs in mouse oocytes, and they are more abundant in oocytes than in granular cells. Furthermore, Arl2 and Arf5 depletion both impeded meiotic progression, but by affecting spindles and microfilaments, respectively. Moreover, Arl2 and Arf5 depletion both significantly increased regular reactive oxygen species levels and decreased mitochondrial membrane potential and autophagy, indicating that oocyte quality was damaged by Arl2 and Arf5 depletion. These results suggest that Arl2 and Arf5 are two novel essential GTPases required for oocyte meiosis and quality control.

Phosphorus is an essential nutrient during plant growth and development. It is involved in the formation of important compounds in plants, such as phospholipids, ATP, and nucleic acids. However, phosphorus is distributed unevenly in most soils, and exists primarily in the form of organophosphorus, which plants cannot use. In this study, the AtPHR1 homolog MdPHR1 was identified in apple. Our results showed that MdPHR1 contained a MYB domain and a coiled-coil domain, which were conserved in AtPHR1. The MdPHR1 transgenic lines had higher acid phosphatase activity and phosphorus content than the wild-type under phosphorus limited conditions. Overexpression of MdPHR1 enhanced tolerance to phosphorus deficiency in apple calli and Arabidopsis seedlings, and MdPHR1 could bind to the P1BS cis-element of MdPAP10 and activated its transcription. Collectively, our experimental evidence suggests that MdPHR1 may be the central regulator of the system controlling transcriptional responses to Pi starvation in apple.

Auxin response factors (ARFs) mediate auxin response gene transcription by directly binding with AuxREs. However, whether ARF family genes involved in anthocyanin accumulation in apple is largely u...

Two new lathyrane-type diterpenoids, jatropodagins A and B (1 and 2), and five known analogues (3–7), were isolated from the stems of Jatropha podagrica. Their structures and absolute configurations were elucidated by spectroscopic data and calculated ECD analyses. The cytotoxicities of all the lathyrane-type diterpenoids (1–7) were evaluated against two human osteosarcoma cell lines (Saos-2 and MG-63). Compound 1 exhibited significant cytotoxic effects against Saos-2 and MG-63 with IC50 values of 8.08 and 14.64 μM, respectively. The IC50 values for the positive control 5-FU against the Saos-2 and MG-63 cell lines were 19.01 and 25.00 μM, respectively. Morphological features of apoptosis activities were evaluated in 1-treated Saos-2 cells and the results confirmed apoptosis in a dose-dependent manner.

Bacteria-induced mineralization is a new technique to produce calcium carbonate in steel slag for the preparation of building materials. Calcium carbonate nanoparticles were precipitated as a result of the enzymatic activity of Bacillus mucilaginous subtilis in steel slag. The crystal structure and morphology of the calcium carbonate precipitate were studied by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), atomic force microscopy (AFM), while thermal properties were studied by thermogravimetric-differential scanning calorimetry (TG-DSC) analysis. The experimental results showed that the microstructure of calcium carbonate precipitate induced by the reproductive enzymes of Bacillus mucilaginous differs from the chemical precipitation in simulated pore solution of steel slag. Powder XRD patterns confirmed the formation of Bacillus mucilaginous subtilis-induced calcium carbonate with an average particle size of 42.1 nm, while the average particle size of the chemically synthesized calcium carbonate was 59.3 nm. Compared with the chemical synthesis, we found that the decomposition temperature of calcite by bacterial precipitation was higher than that for the chemically-precipitated calcite. The compressive strength improved with the amount of bacterial content. Bacterial mineralization could accelerate the rate of carbon sequestration in the mineralization process. The content of calcium carbonate in microbial mineralized steel slag increased obviously. The compressive strength of steel slag mortar with 1.5% bacterial reached up to 51.5 MPa, the compressive strength increased over 50% compared with the carbonized steel slag mortar. The micron-size calcite by bacterial mineralization resulted in a more compact structure. Our study suggests that microbial mineralization technology is a good method to utilize steel slag for building materials.

Excessive application of nitrate, an essential macronutrient and a signal regulating diverse physiological processes, decreases malate accumulation in apple (Malus domestica) fruit, but the underlying mechanism remains poorly understood. Here, we show that an apple BTB/TAZ protein, MdBT2, is involved in regulating malate accumulation and vacuolar pH in response to nitrate. In vitro and in vivo assays indicate that MdBT2 interacts directly with and ubiquitinates a bHLH transcription factor, MdCIbHLH1, via the ubiquitin/26S proteasome pathway in response to nitrate. This ubiquitination results in the degradation of MdCIbHLH1 protein and reduces the transcription of MdCIbHLH1-targeted genes involved in malate accumulation and vacuolar acidification, including MdVHA-A, which encodes a vacuolar H+-ATPase, and MdVHP1, which encodes a vacuolar H+-pyrophosphatase, as well as MdALMT9, which encodes an aluminum-activated malate transporter. A series of transgenic analyses in apple materials including fruits, plantlets, and calli demonstrate that MdBT2 controls nitrate-mediated malate accumulation and vacuolar pH at least partially, if not completely, via regulating the MdCIbHLH1 protein level. Taken together, these findings reveal that MdBT2 regulates the stability of MdCIbHLH1 via ubiquitination in response to nitrate, which in succession transcriptionally reduces the expression of malate-associated genes, thereby controlling malate accumulation and vacuolar acidification in apples under high nitrate supply.

Drought can activate many stress responses in plant growth and development, including the synthesis of epidermal wax and the induction of abscisic acid (ABA), and increased wax accumulation will improve plant drought resistance. Therefore, an examination of wax biosynthesis genes could help to better understand the molecular mechanism of environmental factors regulating wax biosynthesis and the wax associated stress response. Here, we identified the MdCER2 gene from the 'Gala' (Malus× domestica Borkh.) variety of domestic apple, which is a homolog of Arabidopsis AtCER2. It possesses a transferase domain and the protein localizes on the cell membrane. The MdCER2 gene was constitutively expressed in apple tissues and was induced by drought treatment. Finally, we transformed the MdCER2 gene into Arabidopsis to identify its function, and found ectopic expression of MdCER2 promoted accumulation of cuticular wax in both leaves and stems, decreased water loss and permeability in leaves, increased lateral root number, changed plant ABA sensitivity, and increased drought resistance.

Isochorismate synthase (ICS) plays an essential role in the accumulation of salicylic acid (SA) and plant disease resistance. Diseases caused by Botryosphaeria dothidea affect apple yields. Thus, it is important to understand the role of ICS1 in disease resistance to B. dothidea in apple. In this study, SA treatment enhanced the resistance to B. dothidea. MdICS1 was induced by B. dothidea and enhanced the resistance to B. dothidea. MdICS1 promoter analysis indicated that the W-box was vital for the response to B. dothidea treatment. MdWRKY15 was found to interact with the W-box using yeast one-hybrid screening. Subsequently, the interaction was confirmed by EMSA, yeast one-hybrid, ChIP-PCR, and quantitative PCR assays. Moreover, luciferase and GUS analysis further indicated that MdICS1 was transcriptionally activated by MdWRKY15. Finally, we found the function of MdWRKY15 in the resistance to B. dothidea was partially dependent on MdICS1 from the phenotype of transgenic apples and calli. In summary, we revealed that MdWRKY15 activated the transcription of MdICS1 by directly binding to its promoter to increase the accumulation of SA and the expression of disease-related genes, thereby resulting in the enhanced resistance to B. dothidea in the SA biosynthesis pathway.

Protein kinase SOS2L1 phosphorylates the malate transporter ALMT14, resulting in malate excretion from root to rhizosphere to improve cadmium tolerance in apple., Heavy metal contamination is a major environmental and human health hazard in many areas of the world. Organic acids sequester heavy metals and protect plant roots from the effects of toxicity; however, it is largely unknown how these acids are regulated in response to heavy metal stress. Here, protein kinase SOS2L1 from apple was functionally characterized. MdSOS2L1 was found to be involved in the regulation of malate excretion, and to inhibit cadmium uptake into roots. Using the DUAL membrane system in a screen of an apple cDNA library with MdSOS2L1 as bait, a malate transporter, MdALMT14, was identified as an interactor. Bimolecular fluorescence complementation, pull-down, and co-immunoprecipitation assays further indicated the interaction of the two proteins. Transgenic analyses showed that MdSOS2L1 is required for cadmium-induced phosphorylation at the Ser358 site of MdALMT14, a modification that enhanced the stability of the MdALMT14 protein. MdSOS2L1 was also shown to enhance cadmium tolerance in an MdALMT14-dependent manner. This study sheds light on the roles of the MdSOS2L1–MdALMT14 complex in physiological responses to cadmium toxicity.

An organic crystal of 4,4'-bis(N-carbazolyl)-1,1'-biphenyl (pCBP) exhibits time-dependent afterglow color from blue to orange over 1 s. Both experimental and computational data confirm that the color evolution results from well-separated, long-persistent thermally activated delayed fluorescence (TADF) and room-temperature phosphorescence (RTP) with different but comparable decay rates. TADF is enabled by a small S1 -T1 energy gap of 0.7 kcal mol-1 . The good separation of TADF and RTP is due to a 11.8 kcal mol-1 difference in the S0 energies of the S1 and T1 structures, indicating that apart from the excited-state properties, tuning the ground state is also important for luminescence properties. This afterglow color evolution of pCBP allows its applications in anticounterfeiting and data encryption with high security levels.

A bright difluoroboron β-diketonate derivative 1 showing four emission colors (green, yellow, orange and red) with high quantum yields (41–74%) in four polymorphs and one amorphous state is reported. Green-emissive crystals (1-G and 1-G′) exhibit dimeric aggregation structures due to the strong molecular π–π interaction but exhibit hypsochromic emission compared to yellow-emissive crystals (1-Y) with monomeric aggregation because of lacking such π–π interactions. These novel emission phenomena are rationalized by theoretical calculations. High fluorescence sensitivity of compound 1 to its molecular packing modes results in excellent responsive behavior to multiple external stimuli thereby showing reversible change of emission colors under mechanical grinding, heating, solvent fuming and hydrostatic pressure.

Zinc finger proteins are widely involved and play an important role in plant growth and abiotic stress. In this research, MdZAT5, a gene encoding C2H2-type zinc finger protein, was cloned and investigated. The MdZAT5 was highly expressed in flower tissues by qRT-PCR analyses and GUS staining. Promoter analysis showed that MdZAT5 contained multiple response elements, and the expression levels of MdZAT5 were induced by various abiotic stress treatments. Overexpression of MdZAT5 in apple calli positively regulated anthocyanin accumulation by activating the expressions of anthocyanin biosynthesis-related genes. Overexpression of MdZAT5 in Arabidopsis also enhanced the accumulation of anthocyanin. In addition, MdZAT5 increased the sensitivity to salt stress in apple calli. Ectopic expression of MdZAT5 in Arabidopsis reduced the expression of salt-stress-related genes (AtNHX1 and AtABI1) and improved the sensitivity to salt stress. In conclusion, these results suggest that MdZAT5 plays a positive regulatory role in anthocyanin accumulation and negatively regulates salt resistance.

Sugars are essential regulatory molecules involved in plant growth and development and defense response. Although the relationship between sugars and disease resistance has been widely discussed, the underlying molecular mechanisms remain unexplored. Ring rot caused by Botryosphaeria dothidea (B. dothidea), which severely affects fruit quality and yield, is a destructive disease of apples (Malus domestica Borkh.). The present study found that the degree of disease resistance in apple fruit was closely related to glucose content. Therefore, the gene encoding a hexokinase, MdHXK1, was isolated from the apple cultivar 'Gala', and characterized during the defense response. Overexpression of MdHXK1 enhanced disease resistance in apple calli, leaves and fruits by increasing the expression levels of genes related to salicylate (SA) synthesis (PHYTOALEXIN DEFICIENT 4, PAD4; PHENYLALANINE AMMONIA-LYASE, PAL; and ENHANCED DISEASE SUSCEPTIBILITY 1, EDS1) and signaling (PR1; PR5; and NONEXPRESSER OF PR GENES 1, NPR1) as well as increasing the superoxide (O2- ) production rate and the hydrogen peroxide (H2 O2 ) content. Overall, the study provides new insights into the MdHXK1-mediated molecular mechanisms by which glucose signaling regulates apple ring rot resistance.

Nitrate is a major nitrogen resource for plant growth and development and acts as both a crucial nutrient and a signaling molecule for plants; hence, understanding nitrate signaling is important for crop production. Abscisic acid (ABA) has been demonstrated to be involved in nitrate signaling, but the underlying mechanism is largely unknown in apple. In this study, we found that exogenous ABA inhibited the transport of nitrate from roots to shoots in apple, and the transcription of the nitrate transporter MdNRT1.5/MdNPF7.3 was noticeably reduced at the transcriptional level by ABA, which inhibited the transport of nitrate from roots to shoots. Then, it was found that the ABA-responsive transcription factor MdABI5 bound directly to the ABRE recognition site of the MdNRT1.5 promoter and suppressed its expression. Overexpression of MdABI5 inhibited ABA-mediated transport of nitrate from roots to shoots. Overall, these results demonstrate that MdABI5 regulates the transport of nitrate from roots to shoots partially by mediating the expression of MdNRT1.5, illuminating the molecular mechanism by which ABA regulates nitrate transport in apple.

Of all malignant brain tumors, glioma is the deadliest and most common, with a poor prognosis. Drug therapy is considered as a promising way to stop the progression of disease and even cure tumors. However, the presence of blood brain barrier (BBB) and blood tumor barrier (BTB) limits the delivery of these therapeutic genes. In this work, an intelligent cell imaging and cancer therapy drug delivery system targeting the blood-brain barrier and the highly expressed transferrin receptors (TfR) in gliomas has been successfully constructed, and an amphiphilic polymer (PLA-PEG-T7/TPE) with aggregation-induced emission (AIE) properties has been designed and successfully synthesized. PLA-PEG-T7/TPE self-assembled polymer micelles showed significant AIE effect in aqueous solution with good biocompatibility. Therefore, it can be used for potential biological imaging applications. In addition, drug-carrying micelles showed typical behavior of regulating drug release. Inhibition of cell proliferation in vitro showed that the drug-loaded micelles had dose-dependent cytotoxicity to LN229 cells. In the in vivo anti-tumor experiment, PLA-PEG-T7/TPE/TMZ had the best therapeutic effect. These results indicated that T7 functionalized PLA-PEG was a promising platform for nasopharyngeal cancer drug combination therapy.

A superhydrophobic macroporous material composed of hollow hemispherical MXene (HSMX) was synthesized by the thermal annealing of MXene-wrapped cationic polystyrene spheres (CPS@MXene). Notably, the spherical MXene shells exhibited highly efficient catalysis of the carbonization of CPS into carbon nanoparticles. Their insertion into the interlayer of MXene increased the d-spacing and created hollow hemispheres. The as-prepared HSMX with nanoscale walls had a lower packing density than MXene, but higher porosity, total pore volume, and total pore area. Moreover, the stacking of hollow hemispheres promoted the formation of a highly undulating macroporous surface and significantly improved the surface roughness of the HSMX-based 3D membrane, resulting in superhydrophobicity with a water contact angle of 156.4° and a rolling angle of 6°. As a result, the membrane exhibited good separation efficiency and Flux for emulsifier-stabilized water-in-paraffin liquid emulsions, which was dependent on its superhydrophobic performance and strong demulsification ability derived from the razor effect originating from the ultrathin walls of HSMX. This work provides a facile approach for the transformation of highly hydrophilic 2D MXene into superhydrophobic 3D HSMX, and opens a new pathway for the development of advanced MXene-based materials for environmental remediation applications.

Recycling waste tires through pyrolysis technology generates refractory wastewater, which is harmful to the environment if not disposed properly. In this study, a combined process of coagulation detoxification and biodegradation was used to treat tire pyrolysis wastewater. Organics removal characteristics at the molecular level were investigated using electrospray ionization (ESI) coupled with Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). The results showed that nearly 90% of the organic matter from the wastewater was removed through the process. Preference of the two coagulants for different classes of organics in tire pyrolysis wastewater was observed. The covalently bound inorganic-organic hybrid coagulant (CBHyC) used in this work had a complementary relationship with biodegradation for the organics removal: this coagulant reduced toxicity and enhanced the biodegradation by preferentially removing refractory substances such as lignin with a high degree of oxidation (O/C > 0.3). This study provides molecular insight into the organics of tire pyrolysis wastewater removed by a combined treatment process, supporting the advancement and application of waste rubber recycling technology. It also contributes to the possible development of an effective treatment process for refractory wastewater.

Abscisic acid is involved in the regulation of cold stress response, but its molecular mechanism remains to be elucidated. In this study, we demonstrated that the APETALA2/ethylene responsive factor (AP2/ERF) family protein MdABI4 positively regulates abscisic acid-mediated cold tolerance in apple. We found that MdABI4 interacts with MdICE1, a key regulatory protein involved in the cold stress response, and enhances the transcriptional regulatory function of MdICE1 on its downstream target gene MdCBF1, thus improving abscisic acid-mediated cold tolerance. The jasmonate-ZIM domain (JAZ) proteins MdJAZ1 and MdJAZ2 negatively modulate MdABI4-improved cold tolerance in apple by interacting with the MdABI4 protein. Further investigation showed that MdJAZ1 and MdJAZ2 interfere with the interaction between the MdABI4 and MdICE1 proteins. Together, our data revealed that MdABI4 integrates jasmonic acid and abscisic acid signals to precisely modulate cold tolerance in apple through the JAZ-ABI4-ICE1-CBF regulatory cascade. These findings provide insights into the crosstalk between jasmonic acid and abscisic acid signals in response to cold stress.

The purpose of this study was to investigate how pre-hypoxia exposure affected the mitochondrial structure and bioenergetic function of large yellow croaker in responding to Cu stress. Fish were acclimated to normoxia and 3.0 mg DO L−1 for 48 h, then subjected to 0 and 120 μg Cu L−1 for another 48 h. Hypoxic acclimation did not affect mitochondrial ultrastructure and reactive oxygen species (ROS), but reduced oxidative phosphorylation (OXPHOS) efficiency. Cu exposure impaired mitochondrial ultrastructure, increased ROS generation and inhibited OXPHOS efficiency. Compared with Cu exposure alone, hypoxic acclimation plus Cu exposure reduced ROS production and improved OXPHOS efficiency by enhancing mitochondrial respiratory control ratio, mitochondrial membrane potential, and activities and gene expressions of electron transport chain enzymes. In conclusion, hypoxic acclimation improved the mitochondrial energy metabolism of large yellow croaker under Cu stress, facilitating our understanding of the molecular mechanisms regarding adaptive responses of hypoxia-acclimated fish under Cu stress.

Jasmonic acid (JA) plays an important role in regulating leaf senescence. However, the molecular mechanisms of leaf senescence in apple (Malus domestica) remain elusive. In this study, we found that MdZAT10, a C2H2-type zinc finger transcription factor (TF) in apple, markedly accelerates leaf senescence and increases the expression of senescence-related genes. To explore how MdZAT10 promotes leaf senescence, we carried out liquid chromatography/mass spectrometry screening. We found that MdABI5 physically interacts with MdZAT10. MdABI5, an important positive regulator of leaf senescence, significantly accelerated leaf senescence in apple. MdZAT10 was found to enhance the transcriptional activity of MdABI5 for MdNYC1 and MdNYE1, thus accelerating leaf senescence. In addition, we found that MdZAT10 expression was induced by methyl jasmonate (MeJA), which accelerated JA-induced leaf senescence. We also found that the JA-responsive protein MdBT2 directly interacts with MdZAT10 and reduces its protein stability through ubiquitination and degradation, thereby delaying MdZAT10-mediated leaf senescence. Taken together, our results provide new insight into the mechanisms by which MdZAT10 positively regulates JA-induced leaf senescence in apple.

A new terbium (III) luminescent compound {[Tb2(PDC)2(ox)(H2O)4](H2O)2}n was synthesized by the self-assembly of Tb3+ ions with 3,5-pyridinedicarboxylate (PDC) and oxalate (ox) ligands and characterized by fluorescence spectroscopy and single-crystal X-ray diffraction. The density functional theory (DFT) and high-level correlated abinitio wave function methods with Spin-Orbit Coupling correction (CASSCF/SO and CAS-NEVPT2/SOC) were successfully applied to predict the absorption and emission spectra of this strongly correlated lanthanide system in excellent agreement with the experimental results.

Salicylic acid (SA) is closely related to disease resistance of plants. WRKY transcription factors have been linked to the growth and development of plants, especially under stress conditions. However, the regulatory mechanism of WRKY proteins involved in SA production and disease resistance in apple is not clear. In this study, MdPBS3.1 responded to Botryosphaeria dothidea and enhanced resistance to B. dothidea. Electrophoretic mobility shift assays, yeast one-hybrid assays, and chromatin immunoprecipitation and quantitative PCR demonstrated that MdWRKY46 can directly bind to a W-box motif in the promoter of MdPBS3.1. Glucuronidase transactivation and luciferase analysis further showed that MdWRKY46 can activate the expression of MdPBS3.1. Finally, B. dothidea inoculation in transgenic apple calli and fruits revealed that MdWRKY46 improved resistance to B. dothidea by the transcriptional activation of MdPBS3.1. Viral vector-based transformation assays indicated that MdWRKY46 elevates SA content and transcription of SA-related genes, including MdPR1, MdPR5, and MdNPR1 in an MdPBS3.1-dependent way. These findings provide new insights into how MdWRKY46 regulates plant resistance to B. dothidea through the SA signaling pathway.

Sugars are important energy source and signaling molecule in plant, and sugar transporters such as SWEET (sugars will eventually be exported transporters) play important roles in plant growth and development as well as biotic and abiotic stresses. In this study, a gene named MdSWEET17 was isolated from apple (Malus×domestic). Expression analysis suggested that MdSWEET17 expressed in all tested tissues (root, stem, leaf, flower and fruit) and the transcript levels were different. Furthermore, MdSWEET17 transgenic tomatoes and wild type were treated with drought. The results showed transgenic lines had higher drought tolerance and accumulated more fructose. Taken together, these findings indicated that MdSWEET17 take part in drought stress response and the regulation of fructose.

Background The MYB transcription factor family is one of the largest transcriptional factor families in plants and plays a multifaceted role in plant growth and development. However, MYB transcription factors involved in pathogen resistance in apple remain poorly understood. Results We identified a new MYB family member from apple, and named it MdMYB30. MdMYB30 was localized to the nucleus, and was highly expressed in young apple leaves. Transcription of MdMYB30 was induced by abiotic stressors, such as polyethylene glycol and abscisic acid. Scanning electron microscopy and gas chromatograph–mass spectrometry analyses demonstrated that ectopically expressing MdMYB30 in Arabidopsis changed the wax content, the number of wax crystals, and the transcription of wax-related genes. MdMYB30 bound to the MdKCS1 promoter to activate its expression and regulate wax biosynthesis. MdMYB30 also contributed to plant surface properties and increased resistance to the bacterial strain Pst DC3000. Furthermore, a virus-based transformation in apple fruits and transgenic apple calli demonstrated that MdMYB30 increased resistance to Botryosphaeria dothidea. Our findings suggest that MdMYB30 plays a vital role in the accumulation of cuticular wax and enhances disease resistance in apple. Conclusions MdMYB30 bound to the MdKCS1 gene promoter to activate its transcription and regulate cuticular wax content and composition, which influenced the surface properties and expression of pathogenesis-related genes to resistance against pathogens. MdMYB30 appears to be a crucial element in the formation of the plant cuticle and confers apple with a tolerance to pathogens. Electronic supplementary material The online version of this article (10.1186/s12870-019-1918-4) contains supplementary material, which is available to authorized users.

Summary MYB transcription factors (TFs) have been demonstrated to play diverse roles in plant growth and development through interaction with basic helix‐loop‐helix (bHLH) TFs. MdbHLH33, an apple bHLH TF, has been identified as a positive regulator in cold tolerance and anthocyanin accumulation by activating the expressions of MdCBF2 and MdDFR. In the present study, a MYB TF MdMYB308L was found to also positively regulate cold tolerance and anthocyanin accumulation in apple. We found that MdMYB308L interacted with MdbHLH33 and enhanced its binding to the promoters of MdCBF2 and MdDFR. In addition, an apple RING E3 ubiquitin ligase MYB30‐INTERACTING E3 LIGASE 1 (MdMIEL1) was identified to be an MdMYB308L‐interacting protein and promoted the ubiquitination degradation of MdMYB308L, thus negatively regulated cold tolerance and anthocyanin accumulation in apple. These results suggest that MdMYB308L acts as a positive regulator in cold tolerance and anthocyanin accumulation in apple by interacting with MdbHLH33 and undergoes MdMIEL1‐mediated protein degradation. The dynamic change in MYB‐bHLH protein complex seems to play a key role in the regulation of plant growth and development.

To investigate the involvement of peripheral adenosine receptors in the effect of electroacupuncture (EA) on visceral pain in mice with inflammatory bowel disease (IBD). 2,4,6-Trinitrobenzene sulfonic acid (TNBS) was used to induce the visceral pain model. EA (1 mA, 2 Hz, 30 min) treatment was applied to bilateral acupoints “Dachangshu” (BL25) 1 day after TNBS injection once daily for 7 consecutive days. Von Frey filaments were used to measure the mechanical pain threshold. Western blot was used to detect the protein expression levels of adenosine 1 receptor (A1R), adenosine 2a receptor (A2aR), adenosine 2b receptor (A2bR), adenosine 3 receptor (A3R), substance P (SP), and interleukin 1 beta (IL-1β) in colon tissue. EA significantly ameliorated the disease-related indices and reduced the expression of SP and IL-1β in the colon tissues of mice with IBD. EA increased the expression of A1R, A2aR, and A3R and decreased the expression of A2bR in the colon tissue. Furthermore, the administration of adenosine receptor antagonists influenced the effect of EA. EA can inhibit the expression of the inflammatory factors SP and IL-1β by regulating peripheral A1, A2a, A2b, and A3 receptors, thus inhibiting visceral pain in IBD mice. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s11302-019-09655-4) contains supplementary material, which is available to authorized users.

Purpose: We determined whether electroacupuncture (EA) reduces Netrin-1-induced myelinated primary afferent nerve fiber sprouting in the spinal cord and pain hypersensitivity associated with postherpetic neuralgia (PHN) through activation of μ-opioid receptors. Methods: PHN was induced by systemic injection of resiniferatoxin (RTX) in rats. Thirty-six days after RTX injection, a μ-opioid receptor antagonist, beta-funaltrexamine (β-FNA) or a κ-opioid receptor antagonist, nor Binaltorphimine (nor-BNI), was injected intrathecally 30 mins before EA, once every other day for 4 times. Mechanical allodynia was tested with von Frey filaments. The protein expression level of Netrin-1 and its receptors (DCC and UNC5H2) were quantified by using western blotting. The myelinated primary afferent nerve fiber sprouting was mapped with the transganglionic tracer cholera toxin B-subunit (CTB). Results: Treatment with 2 Hz EA at “Huantiao” (GB30) and “Yanglingquan” (GB34) decreased the mechanical allodynia at 22 days and the myelinated primary afferent nerve fiber preternatural sprouting into the lamina II of the spinal dorsal horn at 42 days after RTX injection. Also, treatment with 2 Hz EA reduced the protein levels of DCC and Netrin-1 and promoted the expression of UNC5H2 in the spinal dorsal horn 42 days after RTX injection. Furthermore, the μ-opioid receptor antagonist β-FNA, but not the κ-opioid receptor antagonist nor-BNI, reversed the effect of EA on neuropathic pain caused by RTX. In addition, morphine inhibited the Netrin-1 protein level induced by RTX in SH-SY5Y cells. Conclusions: Through activation of μ-opioid receptors, treatment with EA reduces the expression level of DCC and Netrin-1 and changes a growth-permissive environment in spinal dorsal horn into an inhibitory environment by increasing UNC5H2, thus decreasing RTX-caused primary afferent nerve sprouting in the spinal dorsal horn and neuropathic pain.

The salinity of soil severely restricts the rate of land use and crop productivity. Plants have developed complex mechanisms, including osmotic adjustment, to resist salt stress. Here, we report that the MdALMT14 gene in the apple is a homolog of the Arabidopsis malate acid transporter gene AtALMT14. The expression of MdALMT14 was induced by salt treatment. The ectopic expression of MdALMT14 in Arabidopsis decreased the malondialdehyde (MDA) content and the relative electronic conductivity under salt conditions. In addition, our results showed that MdALMT14 impacted salt tolerance by promoting the accumulation of malic acid in Arabidopsis. The overexpression of MdALMT14 increased salt tolerance in apple calli. Taken together, these findings provide evidence that the apple Aluminum-activated Malate Transporter MdALMT14 is involved in salt stress tolerance and the regulation of malic acid content. These data provide new ideas for further attempts to improve stress tolerance and fruit quality through cultivation and breeding methods.

A 56 day feeding trial was conducted to examine the effects of different levels of dietary histamine on growth performance, immune response, and intestinal health of grouper (Epinephelus coioides). Seven isonitrogenous (46%), isolipidic (10%) diets were prepared with histamine supplement levels of 0 (T0), 0.05% (T1), 0.1% (T2), 0.15% (T3), 0.2% (T4), 0.25% (T5), and 0.3% (T6), respectively. The results showed that histamine supplementation had no significant effects on weight gain rate (WGR), specific growth rate (SGR), feed conversion rate (FCR), hepatosomatic index (HSI), and survival rate (SR) at the initial feeding period (day 0–28), but WGR and SGR had negative linear responses to the dietary histamine level at the whole feeding period (day 0–56), and a significant decrease was observed in groups T5 and T6 compared with T0 (P < 0.05). Supplementation of histamine decreased antioxidant capacity, immune response, the contents of serum interleukin-1 beta (IL-1β), intestinal-type fatty acid-binding protein (FABP2) and intestinal trefoil factor (ITF), and caused serious damage of intestine with significantly decreased VH and MFH of grouper, especially in fish fed with diets supplemented with high doses of histamine (0.25 and 0.3%). The intestinal microbial communities in treatments were different clearly with the control (T0), in terms of beta (β)-diversity boxplots and UPGMA phylogenetic tree based on unweighted unifrac distance. At the phylum level, the relative abundance of Fusobacteria was lower in group T0, while the abundance of Firmicutes was significantly lower in groups T5 and T6 (P < 0.05). At the genus level, the relative abundance of uncultured_bacterium_f_Bacteroidales_S24-7_group, uncultured_bacterium_f_Lachnospiraceae, and Ruminiclostridium were significantly higher in the control, while the abundance of Cetobacterium was significantly higher in groups T5 and T6 (P < 0.05). In conclusion, the present study suggested that up to 0.2% of dietary histamine did not result in a remarkable reduction in growth, immune response, and intestinal health; however, 0.25% or more dietary histamine could cause significant negative effects on growth performance, immune response, and intestinal health in E. coioides.

Fruit coloration is an appearance trait that directly affects the commercial value and market competitiveness of apples. The red color of apple fruit is mainly affected by anthocyanin accumulation, and the synthesis of anthocyanin is affected by various factors. The critical roles of hormones and environmental factors during apple anthocyanin biosynthesis are described. This review also elaborates the specific mechanisms of the responses of internal genes to stress and changes in anthocyanin when apples are exposed to different environmental stressors. This study provides direction for future research on apple anthocyanin and is a reference for anthocyanin studies in other species.