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Enhancer RNAs (eRNAs) transcribed from distal active enhancers serve as key regulators in gene transcriptional regulation. The accumulation of eRNAs from multiple sequencing assays has led to an urgent need to comprehensively collect and process these data to illustrate the regulatory landscape of eRNAs. To address this need, we developed the eRNAbase (http://bio.liclab.net/eRNAbase/index.php) to store the massive available resources of human and mouse eRNAs and provide comprehensive annotation and analyses for eRNAs. The current version of eRNAbase cataloged 10 399 928 eRNAs from 1012 samples, including 858 human samples and 154 mouse samples. These eRNAs were first identified and uniformly processed from 14 eRNA-related experiment types manually collected from GEO/SRA and ENCODE. Importantly, the eRNAbase provides detailed and abundant (epi)genetic annotations in eRNA regions, such as super enhancers, enhancers, common single nucleotide polymorphisms, expression quantitative trait loci, transcription factor binding sites, CRISPR/Cas9 target sites, DNase I hypersensitivity sites, chromatin accessibility regions, methylation sites, chromatin interactions regions, topologically associating domains and RNA spatial interactions. Furthermore, the eRNAbase provides users with three novel analyses including eRNA-mediated pathway regulatory analysis, eRNA-based variation interpretation analysis and eRNA-mediated TF-target gene analysis. Hence, eRNAbase is a powerful platform to query, browse and visualize regulatory cues associated with eRNAs.
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Bases de Datos Genéticas , ARN Potenciadores , Transcripción Genética , Animales , Humanos , Ratones , Cromatina/genética , Regulación de la Expresión GénicaRESUMEN
Transcription factors (TFs), transcription co-factors (TcoFs) and their target genes perform essential functions in diseases and biological processes. KnockTF 2.0 (http://www.licpathway.net/KnockTF/index.html) aims to provide comprehensive gene expression profile datasets before/after T(co)F knockdown/knockout across multiple tissue/cell types of different species. Compared with KnockTF 1.0, KnockTF 2.0 has the following improvements: (i) Newly added T(co)F knockdown/knockout datasets in mice, Arabidopsis thaliana and Zea mays and also an expanded scale of datasets in humans. Currently, KnockTF 2.0 stores 1468 manually curated RNA-seq and microarray datasets associated with 612 TFs and 172 TcoFs disrupted by different knockdown/knockout techniques, which are 2.5 times larger than those of KnockTF 1.0. (ii) Newly added (epi)genetic annotations for T(co)F target genes in humans and mice, such as super-enhancers, common SNPs, methylation sites and chromatin interactions. (iii) Newly embedded and updated search and analysis tools, including T(co)F Enrichment (GSEA), Pathway Downstream Analysis and Search by Target Gene (BLAST). KnockTF 2.0 is a comprehensive update of KnockTF 1.0, which provides more T(co)F knockdown/knockout datasets and (epi)genetic annotations across multiple species than KnockTF 1.0. KnockTF 2.0 facilitates not only the identification of functional T(co)Fs and target genes but also the investigation of their roles in the physiological and pathological processes.
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Bases de Datos Genéticas , Factores de Transcripción , Transcriptoma , Animales , Humanos , Ratones , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Internet , Marcación de Gen , Arabidopsis , Zea maysRESUMEN
Ribosomal frameshifting refers to the process that ribosomes slip into +1 or -1 reading frame, thus produce chimeric trans-frame proteins. In viruses and bacteria, programmed ribosomal frameshifting can produce essential trans-frame proteins for viral replication or regulation of other biological processes. In humans, however, functional trans-frame protein derived from ribosomal frameshifting is scarcely documented. Combining multiple assays, we show that short codon repeats could act as cis-acting elements that stimulate ribosomal frameshifting in humans, abbreviated as CRFS hereafter. Using proteomic analyses, we identified many putative CRFS events from 32 normal human tissues supported by trans-frame peptides positioned at codon repeats. Finally, we show a CRFS-derived trans-frame protein (HDAC1-FS) functions by antagonizing the activities of HDAC1, thus affecting cell migration and apoptosis. These data suggest a novel type of translational recoding associated with codon repeats, which may expand the coding capacity of mRNA and diversify the regulation in human.
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Sistema de Lectura Ribosómico , Proteómica , Humanos , Codón/genética , Codón/metabolismo , Ribosomas/metabolismo , Proteínas Recombinantes de Fusión/metabolismo , Biosíntesis de ProteínasRESUMEN
Heritability is a fundamental concept in genetic studies, measuring the genetic contribution to complex traits and bringing insights about disease mechanisms. The advance of high-throughput technologies has provided many resources for heritability estimation. Linkage disequilibrium (LD) score regression (LDSC) estimates both heritability and confounding biases, such as cryptic relatedness and population stratification, among single-nucleotide polymorphisms (SNPs) by using only summary statistics released from genome-wide association studies. However, only partial information in the LD matrix is utilized in LDSC, leading to loss in precision. In this study, we propose LD eigenvalue regression (LDER), an extension of LDSC, by making full use of the LD information. Compared to state-of-the-art heritability estimating methods, LDER provides more accurate estimates of SNP heritability and better distinguishes the inflation caused by polygenicity and confounding effects. We demonstrate the advantages of LDER both theoretically and with extensive simulations. We applied LDER to 814 complex traits from UK Biobank, and LDER identified 363 significantly heritable phenotypes, among which 97 were not identified by LDSC.
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Estudio de Asociación del Genoma Completo , Polimorfismo de Nucleótido Simple , Estudio de Asociación del Genoma Completo/métodos , Humanos , Desequilibrio de Ligamiento , Modelos Genéticos , Herencia Multifactorial/genética , Fenotipo , Polimorfismo de Nucleótido Simple/genéticaRESUMEN
Single-cell chromatin accessibility sequencing (scCAS) technologies have enabled characterizing the epigenomic heterogeneity of individual cells. However, the identification of features of scCAS data that are relevant to underlying biological processes remains a significant gap. Here, we introduce a novel method Cofea, to fill this gap. Through comprehensive experiments on 5 simulated and 54 real datasets, Cofea demonstrates its superiority in capturing cellular heterogeneity and facilitating downstream analysis. Applying this method to identification of cell type-specific peaks and candidate enhancers, as well as pathway enrichment analysis and partitioned heritability analysis, we illustrate the potential of Cofea to uncover functional biological process.
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Cromatina , Secuencias Reguladoras de Ácidos Nucleicos , Cromatina/genéticaRESUMEN
As a histone acetyltransferase, lysine acetyltransferase 8 (KAT8) participates in diverse biological processes. However, the effect of KAT8 on oocyte maturation in mice remains unclear. In this study, we found that mouse oocytes overexpressing Kat8-OE induced maturation failure manifested reduced rates of GVBD and first polar body emission. In addition, immunostaining results revealed that Kat8 overexpressing oocytes showed inappropriate mitochondrial distribution patterns, overproduction of reactive oxygen species (ROS), accumulation of phosphorylated γH2AX, hyperacetylation of α-tubulin, and severely disrupted spindle/chromosome organization. Moreover, we revealed that Kat8 overexpression induced a decline in SOD1 proteins and KAT8's interaction with SOD1 in mouse ovaries via immunoprecipitation. Western blotting data confirmed that Kat8-OE induced downregulation of SOD1 expression, which is a key factor for the decline of oocyte quality in advanced maternal age. Also, the injection of Myc-Sod1 cRNA could partially rescue maternal age-induced meiotic defects in oocytes. In conclusion, our data demonstrated that high level of KAT8 inhibited SOD1 activity, which in turn induced defects of mitochondrial dynamics, imbalance of redox homeostasis, and spindle/chromosome disorganization during mouse oocyte maturation.
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Histona Acetiltransferasas , Meiosis , Dinámicas Mitocondriales , Oocitos , Animales , Ratones , Histona Acetiltransferasas/metabolismo , Homeostasis , Oocitos/citología , Oocitos/metabolismo , Oxidación-Reducción , Huso Acromático/metabolismo , Superóxido Dismutasa-1/genéticaRESUMEN
BACKGROUND: Drought can result in yield losses, the application of plant growth regulators is an effective measure to improve drought resistance and yield. The objective of the study was to explore the application potential of mepiquat chloride (MC) in regulating soybean yield and drought resistance. METHODS: In this study, a three-year field experiment was designed and combined with drought experiments to measure the yield of popularized varieties during 2021-2022 and drought-resistant and drought-sensitive varieties were selected, and planted in the field in 2023. RESULTS: MC increased the yield of HN84 and HN87 for two consecutive years from 2021 to 2022 and improved their physiological characteristics under field conditions. Under M200 treatment, the yield of HN84 increased by 6.93% and 9.46%, and HN87 increased by 11.11% and 15.72%. Different concentrations of MC have different effects on soybeans. The maximum increase of SOD, POD and proline in HN84 under M400 treatment reached 71.92%, 63.26% and 71.54%, respectively; the maximum increase of SOD, POD and proline in HN87 under M200 treatment reached 21.96%, 93.49% and 40.45%, respectively. In 2023, the foliar application of MC improved the physiological characteristics of HN44 and HN65 under drought-stress conditions. On the eighth day of drought treatment, compared to the drought treatment, the leaf and root dry weight of HN44 under M100 treatment increased by 17.91% and 32.76%, respectively; the dry weight of leaves and roots of HN65 increased by 20.74% and 29.29% under M200 treatment, respectively. MC also reduced malondialdehyde (MDA) content, decreased antioxidant enzyme activity and proline content. In addition, different concentrations of MC increased the chlorophyll fluorescence parameters (Fs, Fv/Fm, YII, and SPAD). In the field, the plant height of the two varieties decreased significantly, the yield increased, the number of two-grain and three-grain pods increased, and the stem length at the bottom and middle decreased with MC induction. CONCLUSIONS: The application of 100-200 mg/L MC effectively improved drought resistance and increased yield. This study provided support for the rational application of MC in soybean production.
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Resistencia a la Sequía , Glycine max , Piperidinas , Glycine max/efectos de los fármacos , Glycine max/crecimiento & desarrollo , Glycine max/fisiología , Glycine max/metabolismo , Reguladores del Crecimiento de las Plantas/farmacología , Reguladores del Crecimiento de las Plantas/metabolismo , Prolina/metabolismoRESUMEN
Herein, the design of conjugated acetylenic polymers (CAPs) featuring diverse spatial arrangements and intramolecular spacers of diacetylene moieties (âC≡CâC≡Câ) for photocatalytic hydrogen peroxide (H2 O2 ) production from water and O2 , without the need for sacrificial agents, is presented. It is shown that the linear configuration of diacetylene moieties within conjugated acetylenic polymers (CAPs) induces a pronounced polarization of electron distribution, which imparts enhanced charge-carrier mobility when compared to CAPs' networks featuring cross-linked arrangements. Moreover, optimizing the intramolecular spacer between diacetylene moieties within the linear structure leads to the exceptional modulation of the band structures, specifically resulting in a downshifted valence band (VB) and rendering the two-electron water oxidation pathway thermodynamically feasible for H2 O2 production. Consequently, the optimized CAPs with a linear configuration (LCAP-2), featuring spatially separated reduction centers (benzene rings) and oxidation centers (diacetylene moieties), exhibit a remarkable H2 O2 yield rate of 920.1 µmol g-1 h-1 , superior than that of the linear LCAP-1 (593.2 µmol g-1 h-1 ) and the cross-linked CCAP (433.4 µmol g-1 h-1 ). The apparent quantum efficiency (AQE) and solar-to-chemical energy conversion (SCC) efficiency of LCAP-2 are calculated to be 9.1% (λ = 420 nm) and 0.59%, respectively, surpassing the performance of most previously reported conjugated polymers.
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The active structural change of actin cytoskeleton is a general host response upon pathogen attack. This study characterized the function of the cotton (Gossypium hirsutum) actin-binding protein VILLIN2 (GhVLN2) in host defense against the soilborne fungus Verticillium dahliae. Biochemical analysis demonstrated that GhVLN2 possessed actin-binding, -bundling, and -severing activities. A low concentration of GhVLN2 could shift its activity from actin bundling to actin severing in the presence of Ca2+. Knockdown of GhVLN2 expression by virus-induced gene silencing reduced the extent of actin filament bundling and interfered with the growth of cotton plants, resulting in the formation of twisted organs and brittle stems with a decreased cellulose content of the cell wall. Upon V. dahliae infection, the expression of GhVLN2 was downregulated in root cells, and silencing of GhVLN2 enhanced the disease tolerance of cotton plants. The actin bundles were less abundant in root cells of GhVLN2-silenced plants than in control plants. However, upon infection by V. dahliae, the number of actin filaments and bundles in the cells of GhVLN2-silenced plants was raised to a comparable level as those in control plants, with the dynamic remodeling of the actin cytoskeleton appearing several hours in advance. GhVLN2-silenced plants exhibited a higher incidence of actin filament cleavage in the presence of Ca2+, suggesting that pathogen-responsive downregulation of GhVLN2 could activate its actin-severing activity. These data indicate that the regulated expression and functional shift of GhVLN2 contribute to modulating the dynamic remodeling of the actin cytoskeleton in host immune responses against V. dahliae.
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Ascomicetos , Verticillium , Gossypium/metabolismo , Resistencia a la Enfermedad/genética , Actinas/metabolismo , Calcio/metabolismo , Verticillium/fisiología , Ascomicetos/metabolismo , Citoesqueleto de Actina/metabolismo , Enfermedades de las Plantas/microbiología , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/metabolismoRESUMEN
PURPOSE: Radiopharmaceutical therapies targeting fibroblast activation protein (FAP) have shown promising efficacy against many tumor types. But radiopharmaceuticals alone in most cases are insufficient to completely eradicate tumor cells, which can partially be attributed to the protective interplay between tumor cells and cancer-associated fibroblasts (CAFs). The C-X-C chemokine receptor type 4/C-X-C motif chemokine 12 (CXCR4/CXCL12) interaction plays an important role in orchestrating tumor cells and CAFs. We hereby investigated the feasibility and efficacy of [177Lu]Lu-DOTAGA.(SA.FAPi)2, a FAP-targeting radiopharmaceutical, in combination with AMD3100, a CXCR4 antagonist, in a preclinical murine model of triple-negative breast cancer (TNBC). METHODS: Public database was first interrogated to reveal the correlation between CAFs' scores and the prognosis of TNBC patients, as well as the expression levels of FAP and CXCR4 in normal tissues and tumors. In vitro therapeutic efficacy regarding cell proliferation, migration, and colony formation was assessed in BALB/3T3 fibroblasts and 4T1 murine breast cancer cells. In vivo therapeutic efficacy was longitudinally monitored using serial 18F-FDG, [18F]AlF-NOTA-FAPI-04, and [68Ga]Ga-DOTA-Pentixafor PET/CT scans and validated using tumor sections through immunohistochemical staining of Ki-67, α-SMA, CXCR4, and CXCL12. Intratumoral abundance of myeloid-derived suppressive cells (MDSCs) was analyzed using flow cytometry in accordance with the PET/CT schedules. Treatment toxicity was evaluated by examining major organs including heart, lung, liver, kidney, and spleen. RESULTS: CAFs' scores negatively correlated with the survival of TNBC patients (p < 0.05). The expression of CXCR4 and FAP was both significantly higher in tumors than in normal tissues. The combination of [177Lu]Lu-DOTAGA.(SA.FAPi)2 and AMD3100 significantly suppressed cell proliferation, migration, and colony formation in cell culture, and exhibited synergistic effects in 4T1 tumor models along with a decreased number of MDSCs. PET/CT imaging revealed lowest tumor accumulation of 18F-FDG and [18F]AlF-NOTA-FAPI-04 on day 13 and day 14 after treatment started, both of which gradually increased at later time points. A similar trend was observed in the IHC staining of Ki-67, α-SMA, and CXCL12. CONCLUSION: The combination of [177Lu]Lu-DOTAGA.(SA.FAPi)2 and AMD3100 is a feasible treatment against TNBC with minimal toxicity in main organs.
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Quimiocina CXCL12 , Receptores CXCR4 , Neoplasias de la Mama Triple Negativas , Receptores CXCR4/metabolismo , Receptores CXCR4/antagonistas & inhibidores , Neoplasias de la Mama Triple Negativas/diagnóstico por imagen , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/radioterapia , Animales , Ratones , Quimiocina CXCL12/metabolismo , Humanos , Línea Celular Tumoral , Femenino , Ciclamas/farmacología , Ciclamas/uso terapéutico , Lutecio , Bencilaminas/farmacología , Compuestos Heterocíclicos/farmacología , Compuestos Heterocíclicos/química , Radiofármacos/uso terapéutico , Radiofármacos/farmacología , Endopeptidasas , Proliferación Celular/efectos de los fármacos , Gelatinasas/metabolismo , Proteínas de la Membrana/metabolismo , Serina Endopeptidasas/metabolismoRESUMEN
BACKGROUND: Neuroepithelial transforming gene 1 (NET1) is a RhoA subfamily guanine nucleotide exchange factor that governs a wide array of biological processes. However, its roles in meiotic oocyte remain unclear. We herein demonstrated that the NET1-HACE1-RAC1 pathway mediates meiotic defects in the progression of oocyte maturation. METHODS: NET1 was reduced using a specific small interfering RNA in mouse oocytes. Spindle assembly, chromosomal alignment, the actin cap, and chromosomal spreads were visualized by immunostaining and analyzed under confocal microscopy. We also applied mass spectroscopy, and western blot analysis for this investigation. RESULTS: Our results revealed that NET1 was localized to the nucleus at the GV stage, and that after GVBD, NET1 was localized to the cytoplasm and predominantly distributed around the chromosomes, commensurate with meiotic progression. NET1 resided in the cytoplasm and significantly accumulated on the spindle at the MI and MII stages. Mouse oocytes depleted of Net1 exhibited aberrant first polar body extrusion and asymmetric division defects. We also determined that Net1 depletion resulted in reduced RAC1 protein expression in mouse oocytes, and that NET1 protected RAC1 from degradation by HACE1, and it was essential for actin dynamics and meiotic spindle formation. Importantly, exogenous RAC1 expression in Net1-depleted oocytes significantly rescued these defects. CONCLUSIONS: Our results suggest that NET1 exhibits multiple roles in spindle stability and actin dynamics during mouse oocyte meiosis.
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Actinas , Huso Acromático , Animales , Ratones , Actinas/metabolismo , Meiosis , Oncogenes , Oocitos/metabolismo , Huso Acromático/metabolismoRESUMEN
As an E3 ubiquitin ligase, F-box and leucine-rich repeat protein 5 (FBXL5) participates in diverse biologic processes. However, the role of Fbxl5 in mouse oocyte meiotic maturation has not yet been fully elucidated. The present study revealed that mouse oocytes depleted of Fbxl5 were unable to complete meiosis, as Fbxl5 silencing led to oocyte meiotic failure with reduced rates of GVBD and polar body extrusion. In addition, Fbxl5 depletion induced aberrant mitochondrial dynamics as we noted the overproduction of reactive oxygen species (ROS) and the accumulation of phosphorylated γH2AX with Fbxl5 knockdown. We also found that Fbxl5-KD led to the abnormal accumulation of CITED2 proteins in mouse oocytes. Our in vitro ubiquitination assay showed that FBXL5 interacted with CITED2 and that it mediated the degradation of CITED2 protein through the ubiquitination-proteasome pathway. Collectively, our data revealed critical functions of FBXL5 in redox hemostasis and spindle assembly during mouse oocyte maturation.
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Proteínas F-Box , Ubiquitina-Proteína Ligasas , Animales , Ratones , Ubiquitina-Proteína Ligasas/metabolismo , Meiosis , Proteínas/metabolismo , Oocitos/metabolismo , Homeostasis , Huso Acromático/metabolismo , Proteínas F-Box/genética , Proteínas F-Box/metabolismoRESUMEN
Idiopathic pulmonary fibrosis (IPF) is a fatal disease characterized by unpredictable progression and limited therapeutic options. Current diagnosis relies on high resolution computed tomography (HRCT), which may not adequately capture early signs of deterioration. The enzyme autotaxin (ATX) emerges as a prominently expressed extracellular secretory enzyme in the lungs of IPF patients. The objective of this study was to evaluate the effectiveness of 18F-labeled ATX-targeted tracer [18F]ATX-1905, in comparison with [18F]FDG, for early fibrosis diagnosis, disease evolution monitoring, and treatment efficacy assessment in bleomycin-induced pulmonary fibrosis (BPF) models. To assess treatment efficacy, mice were treated with two commonly used drugs for IPF, pirfenidone or nintedanib, from Day 9 to Day 23 postbleomycin administration. Lung tissue assessments encompassed inflammation severity via H&E staining, and Ashcroft scoring via Masson staining, alongside quantification of ATX expression through ELISA. Positron emission tomography (PET) imaging employing [18F]FDG and [18F]ATX-1905 tracked disease progression pre- and post-treatment. The extent of pulmonary fibrosis corresponded to changes in ATX expression levels in the BPF mouse model. Notably, [18F]ATX-1905 exhibited elevated uptake in BPF lungs during the progression of the disease, particularly evident at the early stage (Day 9). This uptake was inhibited by an ATX inhibitor, PF-8380, underscoring the specificity of the radiotracer. Conversely, [18F]FDG uptake, peaking at Day 15, decreased subsequently, likely reflective of diminished inflammation. A 2-week treatment regimen using either pirfenidone or nintedanib resulted in notable reductions of ATX expression levels and fibrosis degrees within lung tissues, based on ELISA and Masson staining, as evidenced by PET imaging with [18F]ATX-1905. [18F]FDG uptake also decreased following the treatment period. Additionally, PET/CT imaging extended to a nonhuman primate (NHP) BPF model. The uptake of [18F]ATX-1905 (SUVmax = 2.2) was significantly higher than that of [18F]FDG (SUVmax = 0.7) in fibrotic lung tissue. Using our novel ATX-specific radiotracer [18F]ATX-1905 and PET/CT imaging, we demonstrated excellent ability in early fibrosis detection, disease monitoring, and treatment assessment within lungs of the BPF mouse models. [18F]ATX-1905 displayed remarkable specificity for ATX expression and high sensitivity for ATX alterations, suggesting its potential for monitoring varying ATX expression in lungs of IPF patients.
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Magnetic polymer microspheres have been extensively utilized as separable and highly efficient adsorbents in wastewater treatment. In this study, a series of novel magnetic spongy porous carbon skeleton materials (Mag-SPCS) have been designed and synthesized by acetonitrile suspension precipitation polymerization, which combines the advantages of the acetonitrile precipitation method and the suspension polymerization method. It was demonstrated that the transformation of the material morphology from microspheres to a porous sponge was achieved by a gradual decrease in the usage amount of ethylene glycol. After N,N-dimethyloctadecylamine (C18) was grafted onto the Mag-SPCS materials, the C18-Mag-SPCS materials with a superhigh saturation adsorption capacity and superfast adsorption efficiency were used for the removal of BTEX (toluene, benzene, and para-xylene) in wastewater. Subsequently, the adsorption properties of the composites with different morphologies were evaluated, and the effect of the usage amount of C18 on the adsorption properties of the C18-Mag-SPCS was further investigated. The maximum adsorption capacities of C18-Mag-SPCS for benzene, toluene, and para-xylene were 714.84, 564.32, and 394.48 mg/g, respectively. The adsorption process was conducted in accordance with the proposed secondary and Langmuir models. Finally, the FTIR, XPS, and XRD characterization results before and after adsorption demonstrated that the adsorption mechanism of toluene onto C18-Mag-SPCS was primarily hydrogen bonding, π-π stacking, and van der Waals forces. These findings of the study indicate that the composite material exhibits an ultrahigh saturation adsorption capacity and ultrafast adsorption efficiency, thereby confirming its considerable potential for application in wastewater treatment.
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Investigating the fate of persistent organic pollutants in water distribution systems (WDSs) is of great significance for preventing human health risks. The role of iron corrosion scales in the migration and transformation of organics in such systems remains unclear. Herein, we determined that hydroxyl (â¢OH), chlorine, and chlorine oxide radicals are generated by Fenton-like reactions due to the coexistence of oxygen vacancy-related Fe(II) on goethite (a major constituent of iron corrosion scales) and hypochlorous acid (HClO, the main reactive chlorine species of residual chlorine at pH â¼ 7.0). â¢OH contributed mostly to the decomposition of atrazine (ATZ, model compound) more than other radicals, producing a series of relatively low-toxicity small molecular intermediates. A simplified kinetic model consisting of mass transfer of ATZ and HClO, â¢OH generation, and ATZ oxidation by â¢OH on the goethite surface was developed to simulate iron corrosion scale-triggered residual chlorine oxidation of organic compounds in a WDS. The model was validated by comparing the fitting results to the experimental data. Moreover, the model was comprehensively applicable to cases in which various inorganic ions (Ca2+, Na+, HCO3-, and SO42-) and natural organic matter were present. With further optimization, the model may be employed to predict the migration and accumulation of persistent organic pollutants under real environmental conditions in the WDSs.
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Contaminantes Químicos del Agua , Cinética , Radicales Libres/química , Contaminantes Químicos del Agua/química , Oxidación-Reducción , Hierro/química , Compuestos de Hierro/química , Minerales/químicaRESUMEN
Herein, we propose preferential dissolution paired with Cu-doping as an effective method for synergistically modulating the A- and B-sites of LaMnO3 perovskite. Through Cu-doping into the B-sites of LaMnO3, specifically modifying the B-sites, the double perovskite La2CuMnO6 was created. Subsequently, partial La from the A-sites of La2CuMnO6 was etched using HNO3, forming novel La2CuMnO6/MnO2 (LCMO/MnO2) catalysts. The optimized catalyst, featuring an ideal Mn:Cu ratio of 4.5:1 (LCMO/MnO2-4.5), exhibited exceptional catalytic ozonation performance. It achieved approximately 90% toluene degradation with 56% selectivity toward CO2, even under ambient temperature (35 °C) and a relatively humid environment (45%). Modulation of A-sites induced the elongation of Mn-O bonds and decrease in the coordination number of Mn-O (from 6 to 4.3) in LCMO/MnO2-4.5, resulting in the creation of abundant multivalent Mn and oxygen vacancies. Doping Cu into B-sites led to the preferential chemisorption of toluene on multivalent Cu (Cu(I)/Cu(II)), consistent with theoretical predictions. Effective electronic supplementary interactions enabled the cycling of multiple oxidation states of Mn for ozone decomposition, facilitating the production of reactive oxygen species and the regeneration of oxygen vacancies. This study establishes high-performance perovskites for the synergistic regulation of O3 and toluene, contributing to cleaner and safer industrial activities.
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Ozono , Tolueno , Catálisis , Ozono/química , Tolueno/química , Titanio/química , Óxidos/química , Compuestos de Calcio/químicaRESUMEN
Designing heat-resistant thermosets with excellent comprehensive performance has been a long-standing challenge. Co-curing of various high-performance thermosets is an effective strategy, however, the traditional trial-and-error experiments have long research cycles for discovering new materials. Herein, a two-step machine learning (ML) assisted approach is proposed to design heat-resistant co-cured resins composed of polyimide (PI) and silicon-containing arylacetylene (PSA), that is, poly(silicon-alkyne imide) (PSI). First, two ML prediction models are established to evaluate the processability of PIs and their compatibility with PSA. Then, another two ML models are developed to predict the thermal decomposition temperature and flexural strength of the co-cured PSI resins. The optimal molecular structures and compositions of PSI resins are high-throughput screened. The screened PSI resins are experimentally verified to exhibit enhanced heat resistance, toughness, and processability. The research framework established in this work can be generalized to the rational design of other advanced multi-component polymeric materials.
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Crucial mechanisms are required to restrict self-propagating heterochromatin spreading within defined boundaries and prevent euchromatic gene silencing. In the filamentous fungus Neurospora crassa, the JmjC domain protein DNA METHYLATION MODULATOR-1 (DMM-1) prevents aberrant spreading of heterochromatin, but the molecular details remain unknown. Here, we revealed that DMM-1 is highly enriched in a well-defined 5-kb heterochromatin domain upstream of the cat-3 gene, hereby called 5H-cat-3 domain, to constrain aberrant heterochromatin spreading. Interestingly, aberrant spreading of the 5H-cat-3 domain observed in the dmm-1KO strain is accompanied by robust deposition of histone variant H2A.Z, and deletion of H2A.Z abolishes aberrant spreading of the 5H-cat-3 domain into adjacent euchromatin. Furthermore, lysine 56 of histone H3 is deacetylated at the expanded heterochromatin regions, and mimicking H3K56 acetylation with an H3K56Q mutation effectively blocks H2A.Z-mediated aberrant spreading of the 5H-cat-3 domain. Importantly, genome-wide analyses demonstrated the general roles of H3K56 deacetylation and H2A.Z deposition in aberrant spreading of heterochromatin. Together, our results illustrate a previously unappreciated regulatory process that mediates aberrant heterochromatin spreading.
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Heterocromatina , Histonas , Neurospora crassa/metabolismo , Metilación de ADN , Eucromatina/genética , Estudio de Asociación del Genoma Completo , Heterocromatina/genética , Histonas/genética , Histonas/metabolismoRESUMEN
Megacities face significant pollution challenges, particularly the elevated levels of heavy metals (HMs) in particulate matter (PM). Despite the advent of interdisciplinary and advanced methods for HM source analysis, integrating and applying these approaches to identify HM sources in PM remains a hurdle. This study employs a year-long daily sampling dataset for PM1 and PM1-10 to examine the patterns of HM concentrations under hazy, clean, and rainy conditions in Hangzhou City, aiming to pinpoint the primary sources of HMs in PM. Contrary to other HMs that remained within acceptable limits, the annual average concentrations of Cd and Ni were found to be 20.6 ± 13.6 and 46.9 ± 34.8 ng/m³, respectively, surpassing the World Health Organization's limits by 4.1 and 1.9 times. Remarkably, Cd levels decreased on hazy days, whereas Ni levels were observed to rise on rainy days. Using principal component analysis (PCA), enrichment factor (EF), and backward trajectory analysis, Fe, Mn, Cu, and Zn were determined to be primarily derived from traffic emissions, and there was an interaction between remote migration and local emissions in haze weather. Isotope analysis reveals that Pb concentrations in the Hangzhou region were primarily influenced by emissions from unleaded gasoline, coal combustion, and municipal solid waste incineration, with additional impact from long-range transport; it also highlights nuanced differences between PM1 and PM1-10. Pb isotope and PCA analyses indicate that Ni primarily stemmed from waste incineration emissions. This explanation accounts for the observed higher Ni concentrations on rainy days. Backward trajectory cluster analysis revealed that southern airflows were the primary source of high Cd concentrations on clean days in Hangzhou City. This study employs a multifaceted approach and cross-validation to successfully delineate the sources of HMs in Hangzhou's PM. It offers a methodology for the precise and reliable analysis of complex HM sources in megacity PM.
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Contaminantes Atmosféricos , Monitoreo del Ambiente , Metales Pesados , Material Particulado , Material Particulado/análisis , Metales Pesados/análisis , Contaminantes Atmosféricos/análisis , China , Emisiones de Vehículos/análisisRESUMEN
The removal of various pollutants from water is necessary due to the increasing requirements for the removal of various pollutants from wastewater and the quality of drinking water. Polymer microspheres are regarded as exemplary adsorbent materials due to their high adsorption efficiency, excellent adsorption performance, and ease of handling. Herein, the advantages and disadvantages of different preparation methods, modifications, applications and the current research status of polymer microspheres are summarized at large. Furthermore, the enhanced performance of modified composite microspheres is emphasized, including adsorption efficiency, thermal stability, and significant improvements in physical and chemical properties. Subsequently, the current applications and potential of polymeric microspheres for wastewater treatment, including the removal of inorganic and organic pollutants, heavy metal ions, and other contaminants are summarized. Finally, future research directions for polymer microspheres are proposed, outlining the challenges and solutions associated with the application of polymer microspheres in wastewater treatment.