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Fusarium head blight (FHB), caused by Fusarium graminearum is a devastating disease that affects global wheat production. F. graminearum encodes many effector proteins; however, its virulence mechanisms are poorly understood. In this study, we identify a secretory e ffector c andidate (FgEC10) that is essential for the virulence of F. graminearum . FgEC10 interacts strongly with wheat fumarylacetoacetate hydrolase (TaFAH) and accelerates its degradation via the 26S proteasome pathway. In addition, we show that TaFAH interacts with proteasome 26S subunit, non-ATPases 12 (TaPSMD12) and that FgEC10 enhances the interaction between TaFAH and TaPSMD12. RNA silencing or overexpression of TaFAH in wheat plants shows that TaFAH positively regulates wheat FHB resistance. Overexpression of TaFAH promotes the expression of genes associated with disease resistance and the heading period. Metabolomic analysis reveals that overexpression of TaFAH increases the levels of several amino acids in wheat, and exogenous application of some of these amino acids show an increase in F. graminearum resistance in the wheat spike and seedling. Collectively, our study reveals a pathogenic mechanism and provides a valuable gene resource for improving FHB resistance and promoting heading in wheat. A Fusarium graminearum effector is found to target wheat fumarylacetoacetate hydrolase for 26S proteasomal degradation. The hydrolase enhances resistance to Fusarium head blight by regulating defense genes and amino acid metabolism, offering a genetic target for wheat improvement.

Differences in copper (Cu) absorption and transport, physiological responses and structural characteristics between two types of Cu-resistant plants, Oenothera glazioviana (Cu-exclusion type) and Elsholtzia haichowensis (Cu-enrichment type), were investigated in the present study. The results indicated the following: (1) After 50 μM Cu treatment, the Cu ratio in the xylem vessels of E. haichowensis increased by 60%. A Cu adsorption experiment indicated that O. glazioviana exhibited greater resistance to Cu, and Cu absorption and the shoot/root ratio of Cu were significantly lower in O. glazioviana than in E. haichowensis. (2) An analysis of the endogenous abscisic acid (ABA) variance and exogenous ABA treatment demonstrated that the ABA levels of both plants did not differ; exogenous ABA treatment clearly reduced Cu accumulation in both plants. (3) The leaf stomatal density of O. glazioviana was significantly less than that of E. haichowensis. Guard cells in E. haichowensis plants were covered with a thick cuticle layer, the epidermal hair was more numerous and longer, and the number of xylem conduits in the root was small. (4) The transpiration rate and the stomatal conductance of O. glazioviana were both significantly lower than those of E. haichowensis, regardless of whether the plants were treated with Cu. Taken together, these results indicate that the differences in the structural characteristics between these two plant species, particularly in the characteristics related to plant transpiration, are important factors that govern whether plants acquire or exclude Cu.

Fusarium graminearum (F. graminearum) is the main pathogen of Fusarium head blight (FHB) in wheat, barley, and corn. Deoxynivalenol (DON), produced by F. graminearum, is the most prevalent toxin associated with FHB. The wheat defense compound putrescine can promote DON production during F. graminearum infection. However, the underlying mechanisms of putrescine-induced DON synthesis are not well-studied. To investigate the effect of putrescine on the global transcriptional regulation of F. graminearum, we treated F. graminearum with putrescine and performed RNA deep sequencing. We found that putrescine can largely affect the transcriptome of F. graminearum. Gene ontology (GO) and KEGG enrichment analysis revealed that having a large amount of DEGs was associated with ribosome biogenesis, carboxylic acid metabolism, glycolysis/gluconeogenesis, and amino acid metabolism pathways. Co-expression analysis showed that 327 genes had similar expression patterns to FgTRI genes and were assigned to the same module. In addition, three transcription factor genes were identified as hub genes in this module, indicating that they may play important roles in DON synthesis. These results provide important clues for further analysis of the molecular mechanisms of putrescine-induced DON synthesis and will facilitate the study of the pathogenic mechanisms of FHB.

Little is known about metabolism rates of environmental chemicals by vegetation. A good model compound to study the variation of rates among plant species is cyanide. Vascular plants possess an enzyme system that detoxifies cyanide by converting it to the amino acid asparagine. Knowledge of the kinetic parameters, the half-saturation constant (Km) and the maximum metabolic capacity (vmax), is very useful for enzyme characterization and biochemical purposes. The goal of this study is to find the enzyme kinetics (K(M) and vmax) during cyanide metabolism in the presence of Chinese vegetation, to provide quantitative data for engineered phytoremediation, and to investigate the variation of metabolic rates of plants. Detached leaves (1.0 g fresh weight) from 12 species out of 9 families were kept in glass vessels with 100 mL of aqueous solution spiked with potassium cyanide at 23 degrees C for 28 h. Four different treatment concentrations of cyanide were used, ranging from 0.44 to 7.69 mg CN/L. The disappearance of cyanide from the aqueous solution was analyzed spectrophotometrically. Realistic values of the half-saturation constant (KM) and the maximum metabolic capacity (vmax) were estimated by a computer program using non-linear regression treatments. As a comparison, Lineweaver-Burk plots were also used to estimate the kinetic parameters. The values obtained for K(M) and vmax varied with plant species. Using non-linear regression treatments, values of vmax and K(M) were found in a range between 6.68 and 21.91 mg CN/kg/h and 0.90 to 3.15 mg CN/L, respectively. The highest vmax was by Chinese elder (Sambucus chinensis), followed by upright hedge-parsley (Torilis japonica). The lowest Vmax was demonstrated by the hybrid willow (Salix matssudana x alba). However, the highest K(M) was found in the water lily (Nymphea teragona), followed by the poplar (Populus deltoides Marsh). The lowest K(M) was demonstrated by corn (Zea mays L.). The values of vmax were normally distributed with a mean of 13 mg CN/kg/h. Significant removal of cyanide from aqueous solution was observed in the presence of plant materials without phytotoxicity, even at high doses of cyanide. This gives rise to the conclusion that the Chinese plant species used in this study are all able to efficiently metabolize cyanide, although with different maximum metabolic capacities. A second conclusion is that the variation of metabolism rates between species is small. All these plants had a similar K(M), indicating the same enzyme is active in all plants. Detoxification of cyanide with trees seems to be a feasible option for cleaning soils and water contaminated with cyanide. For phytoremediation projects, screening appropriate plant species adapted to local conditions should be seriously considered. More chemicals should be investigated to find common principles of the metabolism of environmental chemicals by plants.

Fusarium graminearum (F. graminearum) is the main pathogen of Fusarium head blight (FHB) in wheat, barley, and corn. Deoxynivalenol (DON), produced by F. graminearum, is the most prevalent toxin associated with FHB. The wheat defense compound putrescine can promote DON production during F. graminearum infection. However, the underlying mechanisms of putrescine-induced DON synthesis are not well-studied. To investigate the effect of putrescine on the global transcriptional regulation of F. graminearum, we treated F. graminearum with putrescine and performed RNA deep sequencing. We found that putrescine can largely affect the transcriptome of F. graminearum. Gene ontology (GO) and KEGG enrichment analysis revealed that having a large amount of DEGs was associated with ribosome biogenesis, carboxylic acid metabolism, glycolysis/gluconeogenesis, and amino acid metabolism pathways. Co-expression analysis showed that 327 genes had similar expression patterns to FgTRI genes and were assigned to the same module. In addition, three transcription factor genes were identified as hub genes in this module, indicating that they may play important roles in DON synthesis. These results provide important clues for further analysis of the molecular mechanisms of putrescine-induced DON synthesis and will facilitate the study of the pathogenic mechanisms of FHB.

Modulating the surface coordination environment of Pt based nanocrystals at the atomic level is of great importance to obtain good electrocatalytic performance. Given the fundamental understandings of surface structure degeneration of Pt based nanocrystals, introducing a weak electronegative element to the surface of Pt-based catalysts is beneficial for suppressing surface passivation and improving hydrogen evolution reaction performance of Pt. Density functional theory results reveal that the energy barrier of water dissociation process can be greatly reduced by using Se element as the surface modifier to replace the O. This hypothesis is further validated by experiments that ultralong Pt 85 Mo 15 -Se nanowires were fabricated to suppress the excessive passivation behavior of transition metals of Pt based alloy. The Pt 85 Mo 15 -Se nanowires exhibit higher activity with 4.98 times the specific activity and 4.87 times the mass activity of commercial Pt/C, as well as a better stability towards alkaline hydrogen evolution reaction. The deep exploration of X-ray photoelectron spectroscopy and theoretical calculations disclose that Se element could maintain the electron-rich state around the electronic orbit of Pt. This study provides a new insight to advance the fundamental understanding on electrocatalytic materials, which exhibits a promising approach to protect the surface chemical environment of Pt based nanocrystals.

A highly dispersed bimetallic catalyst, AuRu/ZIF-67, and monometallic catalysts, Au/ZIF-67 and Ru/ZIF-67, were successfully prepared herein via co-impregnation/impregnation and hydrogen reduction methods. The catalytic performances of the bimetallic Au–Ru and monometallic Au and Ru catalysts for benzyl alcohol oxidation were compared under an O 2 atmosphere. Results revealed that the addition of Ru to the Au catalyst reduced the oxidation activity of benzyl alcohol while considerably improving the yield of benzaldehyde. The reaction solvent, temperature, pressure and time exerted crucial effects on the catalytic performance of AuRu/ZIF-67. The optimal reaction conditions when using AuRu/ZIF-67 for benzyl alcohol oxidation were 70℃, 5 bar O 2 and 4 h with tetrahydrofuran as the solvent. The benzyl alcohol conversion and benzaldehyde yield were 82.9% and 47.5%, respectively, under the optimal reaction conditions. AuRu/ZIF-67 exhibited excellent applicability towards alcohols; particularly for aromatic and aliphatic alcohols, where good conversions and acceptable yields of aldehydes were obtained. Moreover, the AuRu/ZIF-67 catalyst demonstrated good stability for benzyl alcohol oxidation, and it could be recycled four times without any changes in the benzaldehyde yield.

Selective hydrogenation of 1,3-butadiene is a crucial industrial process for the removing of 1,3-butadiene, a byproduct of butene production. Developing catalysts with high catalytic performance for the hydrogenation of 1,3-butadiene at low temperatures has become a research hotspot. In this study, bimetallic Pd–Co catalysts supported on Al 2 O 3 derived from MIL-53(Al) at various calcination temperatures were synthesised via the co-impregnation method. These catalysts were structurally characterised using powder X-ray diffraction, thermogravimetric analysis, N 2 adsorption–desorption, X-ray photoelectron spectroscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, and inductively coupled plasma optical emission spectroscopy techniques. The characterisations revealed that Pd–Co nanoparticles, averaging 8.5–12.4 nm, were highly dispersed on Al 2 O 3 derived from MIL-53(Al). The effects of reaction temperature, Pd and Co contents, space velocity, and calcination temperature on the catalytic performance for the hydrogenation of 1,3-butadiene were thoroughly investigated. The PdCo/MIL-53(Al)-A700 catalyst exhibited the highest catalytic activity for the hydrogenation of 1,3-butadiene at 40 °C and a space velocity of 900 L/(h·g cat ). This catalyst demonstrated a strong synergistic interaction between Pd and Co nanoparticles, resulting in considerably better catalytic performance than the monometallic Pd catalyst under the same conditions. The PdCo/MIL-53(Al)-A700 catalyst achieved superior 1,3-butadiene conversion and total butene selectivity compared to the Pd/MIL-53(Al)-A700 catalyst. In addition, the PdCo/MIL-53(Al)-A700 catalyst maintained its catalytic activity and total butene selectivity after three regenerations in a flow of N 2 at 200 °C. This work proposed a new pathway to design efficient and sustainable catalysts for 1,3-butadiene hydrogenation.

Background Esophageal squamous cell carcinoma (ESCC) is a highly aggressive and treatment‐resistant tumor. The biological implications and molecular mechanism of cancer stem‐like cells (CSCs) in ESCC, which contribute to therapeutic resistance such as radioresistance, remain elusive. Methods Quantitative real‐time polymerase chain reaction, western blotting, immunohistochemistry, and in situ hybridization assays were used to detect methyltransferase‐like 14 miR‐99a‐5p tribble 2 (METTL14/miR‐99a‐5p/TRIB2) expression in ESCC. The biological functions of METTL14/miR‐99a‐5p/TRIB2 were demonstrated in vitro and in vivo. Mass spectrum analysis was used to identify the downstream proteins regulated by TRIB2. Chromatin immunoprecipitation (IP), IP, N6‐methyladenosine (m6A)‐RNA IP, luciferase reporter, and ubiquitination assays were employed to explore the molecular mechanisms underlying this feedback circuit and its downstream pathways. Results We found that miR‐99a‐5p was significantly decreased in ESCC. miR‐99a‐5p inhibited CSCs persistence and the radioresistance of ESCC cells, and miR‐99a‐5p downregulation predicted an unfavorable prognosis of ESCC patients. Mechanically, we unveiled a METTL14‐miR‐99a‐5p‐TRIB2 positive feedback loop that enhances CSC properties and radioresistance of ESCC cells. METTL14, an m6A RNA methyltransferase downregulated in ESCC, suppresses TRIB2 expression via miR‐99a‐5p‐mediated degradation of TRIB2 mRNA by targeting its 3′ untranslated region, whereas TRIB2 induces ubiquitin‐mediated proteasomal degradation of METTL14 in a COP1‐dependent manner. METTL14 upregulates miR‐99a‐5p by modulating m6A‐mediated, DiGeorge critical region 8‐dependent pri‐mir‐99a processing. Hyperactivation of TRIB2 resulting from this positive circuit was closely correlated with radioresistance and CSC characteristics. Furthermore, TRIB2 activates HDAC2 and subsequently induces p21 epigenetic repression through Akt/mTOR/S6K1 signaling pathway activation. Pharmacologic inhibition of HDAC2 effectively attenuates the TRIB2‐mediated effect both in vitro and in patient‐derived xenograft models. Conclusion Our data highlight the presence of the METTL14/miR‐99a‐5p/TRIB2 axis and show that it is positively associated with CSC characteristics and radioresistance of ESCC, suggesting potential therapeutic targets for ESCC treatment. 1. METTL14 upregulates miR‐99a‐5p by promoting m6A‐mediated, DGCR8‐dependent pri‐mir‐99a processing. 2. miR‐99a‐5p induces degradation of TRIB2 mRNA by targeting its 3′ UTR. 3. TRIB2 induces ubiquitin‐mediated proteasomal degradation of METTL14 in a COP1‐dependent manner. 4. METTL14/miR‐99a‐5p/TRIB2 constitutes a positive feedback loop that enhances CSC properties and radioresistance of ESCC cells through inducing HDAC2‐mediated p21 epigenetic repression dependent on Akt/mTOR/S6K1 pathway.

Postsynthetic modification of metal-organic framework is a general and practical approach to access MOF-based catalysts bearing multiple active sites. The isoreticular metal–organic framework-3 (IRMOF-3) was modified with lactic acid through condensation reaction of the carboxyl group of lactic acid and amino group present in IRMOF-3 frameworks. Au 3+ was subsequently anchored onto the metal–organic framework IRMOF-3 using postsynthetic modification. The synthezized IRMOF-3-LA-Au (LA = lactic acid) was characterized by powder X-ray diffraction, N 2 adsorption-desorption, infrared spectroscopy, liquid-state nuclear magnetic resonance, thermogravimetric analysis, H 2 -temperature programmed reduction, transmission electro microscopy, and inductively coupled plasma–optical emission spectrometry. IRMOF-3-LA-Au acted as an efficient heterogeneous catalyst in the synthesis of propargylamines by three-component coupling reaction of aldehyde, alkyne, and amine. Moreover, the catalyst is applicable to various substituted substrates, including aromatic and aliphatic aldehydes, alkyl- and aryl-substituted terminal alkynes, and alicyclic amines. In addition, the catalyst can be easily separated from the mixture and can be reused for four consecutive cycles.