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Colorectal cancers (CRCs) arise from precursor polyps whose cellular origins, molecular heterogeneity, and immunogenic potential may reveal diagnostic and therapeutic insights when analyzed at high resolution. We present a single-cell transcriptomic and imaging atlas of the two most common human colorectal polyps, conventional adenomas and serrated polyps, and their resulting CRC counterparts. Integrative analysis of 128 datasets from 62 participants reveals adenomas arise from WNT-driven expansion of stem cells, while serrated polyps derive from differentiated cells through gastric metaplasia. Metaplasia-associated damage is coupled to a cytotoxic immune microenvironment preceding hypermutation, driven partly by antigen-presentation differences associated with tumor cell-differentiation status. Microsatellite unstable CRCs contain distinct non-metaplastic regions where tumor cells acquire stem cell properties and cytotoxic immune cells are depleted. Our multi-omic atlas provides insights into malignant progression of colorectal polyps and their microenvironment, serving as a framework for precision surveillance and prevention of CRC.
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Pólipos del Colon/patología , Neoplasias Colorrectales/patología , Microambiente Tumoral , Inmunidad Adaptativa , Adenoma/genética , Adenoma/patología , Adulto , Anciano , Animales , Carcinogénesis/genética , Carcinogénesis/patología , Muerte Celular , Diferenciación Celular , Pólipos del Colon/genética , Pólipos del Colon/inmunología , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/inmunología , Progresión de la Enfermedad , Femenino , Regulación Neoplásica de la Expresión Génica , Redes Reguladoras de Genes , Heterogeneidad Genética , Humanos , Masculino , Ratones , Persona de Mediana Edad , Mutación/genética , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , RNA-Seq , Reproducibilidad de los Resultados , Análisis de la Célula Individual , Microambiente Tumoral/inmunologíaRESUMEN
All-carbon materials based on sp2-hybridized atoms, such as fullerenes1, carbon nanotubes2 and graphene3, have been much explored due to their remarkable physicochemical properties and potential for applications. Another unusual all-carbon allotrope family are the cyclo[n]carbons (Cn) consisting of two-coordinated sp-hybridized atoms. They have been studied in the gas phase since the twentieth century4-6, but their high reactivity has meant that condensed-phase synthesis and real-space characterization have been challenging, leaving their exact molecular structure open to debate7-11. Only in 2019 was an isolated C18 generated on a surface and its polyynic structure revealed by bond-resolved atomic force microscopy12,13, followed by a recent report14 on C16. The C18 work trigged theoretical studies clarifying the structure of cyclo[n]carbons up to C100 (refs. 15-20), although the synthesis and characterization of smaller Cn allotropes remains difficult. Here we modify the earlier on-surface synthesis approach to produce cyclo[10]carbon (C10) and cyclo[14]carbon (C14) via tip-induced dehalogenation and retro-Bergman ring opening of fully chlorinated naphthalene (C10Cl8) and anthracene (C14Cl10) molecules, respectively. We use atomic force microscopy imaging and theoretical calculations to show that, in contrast to C18 and C16, C10 and C14 have a cumulenic and cumulene-like structure, respectively. Our results demonstrate an alternative strategy to generate cyclocarbons on the surface, providing an avenue for characterizing annular carbon allotropes for structure and stability.
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The most massive and shortest-lived stars dominate the chemical evolution of the pre-galactic era. On the basis of numerical simulations, it has long been speculated that the mass of such first-generation stars was up to several hundred solar masses1-4. The very massive first-generation stars with a mass range from 140 to 260 solar masses are predicted to enrich the early interstellar medium through pair-instability supernovae (PISNe)5. Decades of observational efforts, however, have not been able to uniquely identify the imprints of such very massive stars on the most metal-poor stars in the Milky Way6,7. Here we report the chemical composition of a very metal-poor (VMP) star with extremely low sodium and cobalt abundances. The sodium with respect to iron in this star is more than two orders of magnitude lower than that of the Sun. This star exhibits very large abundance variance between the odd- and even-charge-number elements, such as sodium/magnesium and cobalt/nickel. Such peculiar odd-even effect, along with deficiencies of sodium and α elements, are consistent with the prediction of primordial pair-instability supernova (PISN) from stars more massive than 140 solar masses. This provides a clear chemical signature indicating the existence of very massive stars in the early universe.
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Leveraging iterative alignment search through genomic and metagenome sequence databases, we report the DeepMSA2 pipeline for uniform protein single- and multichain multiple-sequence alignment (MSA) construction. Large-scale benchmarks show that DeepMSA2 MSAs can remarkably increase the accuracy of protein tertiary and quaternary structure predictions compared with current state-of-the-art methods. An integrated pipeline with DeepMSA2 participated in the most recent CASP15 experiment and created complex structural models with considerably higher quality than the AlphaFold2-Multimer server (v.2.2.0). Detailed data analyses show that the major advantage of DeepMSA2 lies in its balanced alignment search and effective model selection, and in the power of integrating huge metagenomics databases. These results demonstrate a new avenue to improve deep learning protein structure prediction through advanced MSA construction and provide additional evidence that optimization of input information to deep learning-based structure prediction methods must be considered with as much care as the design of the predictor itself.
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Aprendizaje Profundo , Biología Computacional/métodos , Proteínas/genética , Proteínas/química , Alineación de Secuencia , Genómica , AlgoritmosRESUMEN
Transcriptome-wide association studies (TWAS) have identified many putative susceptibility genes for colorectal cancer (CRC) risk. However, susceptibility miRNAs, critical dysregulators of gene expression, remain unexplored. We genotyped DNA samples from 313 CRC East Asian patients and performed small RNA sequencing in their normal colon tissues distant from tumors to build genetic models for predicting miRNA expression. We applied these models and data from genome-wide association studies (GWAS) including 23 942 cases and 217 267 controls of East Asian ancestry to investigate associations of predicted miRNA expression with CRC risk. Perturbation experiments separately by promoting and inhibiting miRNAs expressions and further in vitro assays in both SW480 and HCT116 cells were conducted. At a Bonferroni-corrected threshold of P < 4.5 × 10-4, we identified two putative susceptibility miRNAs, miR-1307-5p and miR-192-3p, located in regions more than 500 kb away from any GWAS-identified risk variants in CRC. We observed that a high predicted expression of miR-1307-5p was associated with increased CRC risk, while a low predicted expression of miR-192-3p was associated with increased CRC risk. Our experimental results further provide strong evidence of their susceptible roles by showing that miR-1307-5p and miR-192-3p play a regulatory role, respectively, in promoting and inhibiting CRC cell proliferation, migration, and invasion, which was consistently observed in both SW480 and HCT116 cells. Our study provides additional insights into the biological mechanisms underlying CRC development.
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Neoplasias Colorrectales , MicroARNs , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Transcriptoma/genética , Estudio de Asociación del Genoma Completo , Neoplasias Colorrectales/metabolismo , Células HCT116 , Regulación Neoplásica de la Expresión Génica/genética , Proliferación Celular/genéticaRESUMEN
The breakthrough in cryo-electron microscopy (cryo-EM) technology has led to an increasing number of density maps of biological macromolecules. However, constructing accurate protein complex atomic structures from cryo-EM maps remains a challenge. In this study, we extend our previously developed DEMO-EM to present DEMO-EM2, an automated method for constructing protein complex models from cryo-EM maps through an iterative assembly procedure intertwining chain- and domain-level matching and fitting for predicted chain models. The method was carefully evaluated on 27 cryo-electron tomography (cryo-ET) maps and 16 single-particle EM maps, where DEMO-EM2 models achieved an average TM-score of 0.92, outperforming those of state-of-the-art methods. The results demonstrate an efficient method that enables the rapid and reliable solution of challenging cryo-EM structure modeling problems.
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Microscopía por Crioelectrón , Microscopía por Crioelectrón/métodos , Modelos Moleculares , Conformación ProteicaRESUMEN
High salinity, an adverse environmental factor affecting about 20% of irrigated arable land worldwide, inhibits plant growth and development by causing oxidative stress, damaging cellular components, and disturbing global metabolism. However, whether and how reactive oxygen species disturb the metabolism of salt-stressed plants remain elusive. Here, we report that salt-induced hydrogen peroxide (H2O2) inhibits the activity of plastid triose phosphate isomerase (pdTPI) to promote methylglyoxal (MG) accumulation and stimulates the sulfenylation of pdTPI at cysteine 74. We also show that MG is a key factor limiting the plant growth, as a decrease in MG levels completely rescued the stunted growth and repressed salt stress tolerance of the pdtpi mutant. Furthermore, targeting CATALASE 2 into chloroplasts to prevent salt-induced overaccumulation of H2O2 conferred salt stress tolerance, revealing a role for chloroplastic H2O2 in salt-caused plant damage. In addition, we demonstrate that the H2O2-mediated accumulation of MG in turn induces H2O2 production, thus forming a regulatory loop that further inhibits the pdTPI activity in salt-stressed plants. Our findings, therefore, illustrate how salt stress induces MG production to inhibit the plant growth.
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Peróxido de Hidrógeno , Piruvaldehído , Peróxido de Hidrógeno/metabolismo , Piruvaldehído/metabolismo , Estrés Salino , Estrés Oxidativo , Plantas/metabolismo , Cloroplastos/metabolismo , Estrés FisiológicoRESUMEN
Compact Cas9 nucleases hold great promise for therapeutic applications. Although several compact Cas9 nucleases have been developed, many genomic loci still could not be edited due to a lack of protospacer adjacent motifs (PAMs). We previously developed a compact SlugCas9 recognizing an NNGG PAM. Here we demonstrate that SlugCas9 displays comparable activity to SpCas9. We developed a simple phage-assisted evolution to engineer SlugCas9 for unique PAM requirements. Interestingly, we generated a SlugCas9 variant (SlugCas9-NNG) that could recognize an NNG PAM, expanding the targeting scope. We further developed a SlugCas9-NNG-based adenine base editor and demonstrated that it could be delivered by a single adeno-associated virus to disrupt PCSK9 splice donor and splice acceptor. These genome editors greatly enhance our ability for in vivo genome editing.
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Bacteriófagos , Sistemas CRISPR-Cas , Sistemas CRISPR-Cas/genética , Proproteína Convertasa 9 , Adenina , Endonucleasas/genéticaRESUMEN
Teleost IgM+ B cells can phagocytose, like mammalian B1 cells, and secrete Ag-specific IgM, like mammalian B2 cells. Therefore, teleost IgM+ B cells may have the functions of both mammalian B1 and B2 cells. To support this view, we initially found that grass carp (Ctenopharyngodon idella) IgM+ plasma cells (PCs) exhibit robust phagocytic ability, akin to IgM+ naive B cells. Subsequently, we sorted grass carp IgM+ PCs into two subpopulations: nonphagocytic (Pha-IgM+ PCs) and phagocytic IgM+ PCs (Pha+IgM+ PCs), both of which demonstrated the capacity to secrete natural IgM with LPS and peptidoglycan binding capacity. Remarkably, following immunization of grass carp with an Ag, we observed that both Pha-IgM+ PCs and Pha+IgM+ PCs could secrete Ag-specific IgM. Furthermore, in vitro concatenated phagocytosis experiments in which Pha-IgM+ PCs from an initial phagocytosis experiment were sorted and exposed again to beads confirmed that these cells also have phagocytic capabilities, thereby suggesting that all teleost IgM+ B cells have phagocytic potential. Additionally, we found that grass carp IgM+ PCs display classical phenotypic features of macrophages, providing support for the hypothesis that vertebrate B cells evolved from ancient phagocytes. These findings together reveal that teleost B cells are a primitive B cell type with functions reminiscent of both mammalian B1 and B2 cells, providing insights into the origin and evolution of B cells in vertebrates.
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The high-valent cobalt-oxo species (Co(IV)=O) is being increasingly investigated for water purification because of its high redox potential, long half-life, and antiinterference properties. However, generation of Co(IV)=O is inefficient and unsustainable. Here, a cobalt-single-atom catalyst with N/O dual coordination was synthesized by O-doping engineering. The O-doped catalyst (Co-OCN) greatly activated peroxymonosulfate (PMS) and achieved a pollutant degradation kinetic constant of 73.12 min-1 g-2, which was 4.9 times higher than that of Co-CN (catalyst without O-doping) and higher than those of most reported single-atom catalytic PMS systems. Co-OCN/PMS realized Co(IV)=O dominant oxidation of pollutants by increasing the steady-state concentration of Co(IV)=O (1.03 × 10-10 M) by 5.9 times compared with Co-CN/PMS. A competitive kinetics calculation showed that the oxidation contribution of Co(IV)=O to micropollutant degradation was 97.5% during the Co-OCN/PMS process. Density functional theory calculations showed that O-doping influenced the charge density (increased the Bader charge transfer from 0.68 to 0.85 e), optimized the electron distribution of the Co center (increased the d-band center from -1.14 to -1.06 eV), enhanced the PMS adsorption energy from -2.46 to -3.03 eV, and lowered the energy barrier for generation of the key reaction intermediate (*O*H2O) during Co(IV)=O formation from 1.12 to 0.98 eV. The Co-OCN catalyst was fabricated on carbon felt for a flow-through device, which achieved continuous and efficient removal of micropollutants (degradation efficiency of >85% after 36 h operation). This study provides a new protocol for PMS activation and pollutant elimination through single-atom catalyst heteroatom-doping and high-valent metal-oxo formation during water purification.
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piRNA and PIWI proteins have been confirmed for disease diagnosis and treatment as novel biomarkers due to its abnormal expression in various cancers. However, the current research is not strong enough to further clarify the functions of piRNA in cancer and its underlying mechanism. Therefore, how to provide large-scale and serious piRNA candidates for biological research has grown up to be a pressing issue. In this study, a novel computational model based on the structural perturbation method is proposed to predict potential disease-associated piRNAs, called SPRDA. Notably, SPRDA belongs to positive-unlabeled learning, which is unaffected by negative examples in contrast to previous approaches. In the 5-fold cross-validation, SPRDA shows high performance on the benchmark dataset piRDisease, with an AUC of 0.9529. Furthermore, the predictive performance of SPRDA for 10 diseases shows the robustness of the proposed method. Overall, the proposed approach can provide unique insights into the pathogenesis of the disease and will advance the field of oncology diagnosis and treatment.
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Neoplasias , ARN de Interacción con Piwi , Humanos , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Neoplasias/genética , Neoplasias/metabolismoRESUMEN
Flowering is an essential process in fruit trees. Flower number and timing have a substantial impact on the yield and maturity of fruit. Ethylene and gibberellin (GA) play vital roles in flowering, but the mechanism of coordinated regulation of flowering in woody plants by GA and ethylene is still unclear. In this study, a lemon (Citrus limon L. Burm) 1-aminocyclopropane-1-carboxylic acid synthase gene (CiACS4) was overexpressed in Nicotiana tabacum and resulted in late flowering and increased flower number. Further transformation of citrus revealed that ethylene and starch content increased, and soluble sugar content decreased in 35S:CiACS4 lemon. Inhibition of CiACS4 in lemon resulted in effects opposite to that of 35S:CiACS4 in transgenic plants. Overexpression of the CiACS4-interacting protein ETHYLENE RESPONSE FACTOR3 (CiERF3) in N. tabacum resulted in delayed flowering and more flowers. Further experiments revealed that the CiACS4-CiERF3 complex can bind the promoters of FLOWERING LOCUS T (CiFT) and GOLDEN2-LIKE (CiFE) and suppress their expression. Moreover, overexpression of CiFE in N. tabacum led to early flowering and decreased flowers, and ethylene, starch, and soluble sugar contents were opposite to those in 35S:CiACS4 transgenic plants. Interestingly, CiFE also bound the promoter of CiFT. Additionally, GA3 and 1-aminocyclopropanecarboxylic acid (ACC) treatments delayed flowering in adult citrus, and treatment with GA and ethylene inhibitors increased flower number. ACC treatment also inhibited the expression of CiFT and CiFE. This study provides a theoretical basis for the application of ethylene to regulate flower number and mitigate the impacts of extreme weather on citrus yield due to delayed flowering.
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Citrus , Etilenos , Flores , Regulación de la Expresión Génica de las Plantas , Giberelinas , Proteínas de Plantas , Plantas Modificadas Genéticamente , Giberelinas/metabolismo , Citrus/genética , Citrus/fisiología , Citrus/crecimiento & desarrollo , Flores/genética , Flores/fisiología , Flores/crecimiento & desarrollo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Etilenos/metabolismo , Nicotiana/genética , Nicotiana/fisiología , Nicotiana/crecimiento & desarrollo , Liasas/metabolismo , Liasas/genéticaRESUMEN
Remote memory usually decreases over time, whereas remote drug-cue associated memory exhibits enhancement, increasing the risk of relapse during abstinence. Memory system consolidation is a prerequisite for remote memory formation, but neurobiological underpinnings of the role of consolidation in the enhancement of remote drug memory are unclear. Here, we found that remote cocaine-cue associated memory was enhanced in rats that underwent self-administration training, together with a progressive increase in the response of prelimbic cortex (PrL) CaMKII neurons to cues. System consolidation was required for the enhancement of remote cocaine memory through PrL CaMKII neurons during the early period post-training. Furthermore, dendritic spine maturation in the PrL relied on the basolateral amygdala (BLA) input during the early period of consolidation, contributing to remote memory enhancement. These findings indicate that memory consolidation drives the enhancement of remote cocaine memory through a time-dependent increase in activity and maturation of PrL CaMKII neurons receiving a sustained BLA input.
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Complejo Nuclear Basolateral , Cocaína , Consolidación de la Memoria , Neuronas , Corteza Prefrontal , Animales , Consolidación de la Memoria/efectos de los fármacos , Consolidación de la Memoria/fisiología , Cocaína/farmacología , Masculino , Ratas , Corteza Prefrontal/efectos de los fármacos , Corteza Prefrontal/metabolismo , Corteza Prefrontal/fisiología , Complejo Nuclear Basolateral/efectos de los fármacos , Complejo Nuclear Basolateral/metabolismo , Neuronas/metabolismo , Neuronas/efectos de los fármacos , Memoria a Largo Plazo/efectos de los fármacos , Memoria a Largo Plazo/fisiología , Señales (Psicología) , Ratas Sprague-Dawley , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Autoadministración , Espinas Dendríticas/efectos de los fármacos , Espinas Dendríticas/metabolismo , Espinas Dendríticas/fisiología , Trastornos Relacionados con Cocaína/metabolismo , Trastornos Relacionados con Cocaína/fisiopatología , Memoria/efectos de los fármacos , Memoria/fisiologíaRESUMEN
The plant hormone auxin has crucial roles in almost all aspects of plant growth and development. Concentrations of auxin vary across different tissues, mediating distinct developmental outcomes and contributing to the functional diversity of auxin. However, the mechanisms that underlie these activities are poorly understood. Here we identify an auxin signalling mechanism, which acts in parallel to the canonical auxin pathway based on the transport inhibitor response1 (TIR1) and other auxin receptor F-box (AFB) family proteins (TIR1/AFB receptors)1,2, that translates levels of cellular auxin to mediate differential growth during apical-hook development. This signalling mechanism operates at the concave side of the apical hook, and involves auxin-mediated C-terminal cleavage of transmembrane kinase 1 (TMK1). The cytosolic and nucleus-translocated C terminus of TMK1 specifically interacts with and phosphorylates two non-canonical transcriptional repressors of the auxin or indole-3-acetic acid (Aux/IAA) family (IAA32 and IAA34), thereby regulating ARF transcription factors. In contrast to the degradation of Aux/IAA transcriptional repressors in the canonical pathway, the newly identified mechanism stabilizes the non-canonical IAA32 and IAA34 transcriptional repressors to regulate gene expression and ultimately inhibit growth. The auxin-TMK1 signalling pathway originates at the cell surface, is triggered by high levels of auxin and shares a partially overlapping set of transcription factors with the TIR1/AFB signalling pathway. This allows distinct interpretations of different concentrations of cellular auxin, and thus enables this versatile signalling molecule to mediate complex developmental outcomes.
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Proteínas de Arabidopsis/metabolismo , Arabidopsis/crecimiento & desarrollo , Arabidopsis/metabolismo , Ácidos Indolacéticos/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de Señal , Secuencia de Aminoácidos , Arabidopsis/citología , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas F-Box/metabolismo , Ácidos Indolacéticos/antagonistas & inhibidores , Mutación , Reguladores del Crecimiento de las Plantas/antagonistas & inhibidores , Unión Proteica , Proteínas Serina-Treonina Quinasas/genética , Receptores de Superficie Celular/metabolismo , Proteínas Represoras/genética , Proteínas Represoras/metabolismoRESUMEN
In search of redox mechanisms in breast cancer, we uncovered a striking role for glutathione peroxidase 2 (GPx2) in oncogenic signaling and patient survival. GPx2 loss stimulates malignant progression due to reactive oxygen species/hypoxia inducible factor-α (HIF1α)/VEGFA (vascular endothelial growth factor A) signaling, causing poor perfusion and hypoxia, which were reversed by GPx2 reexpression or HIF1α inhibition. Ingenuity Pathway Analysis revealed a link between GPx2 loss, tumor angiogenesis, metabolic modulation, and HIF1α signaling. Single-cell RNA analysis and bioenergetic profiling revealed that GPx2 loss stimulated the Warburg effect in most tumor cell subpopulations, except for one cluster, which was capable of oxidative phosphorylation and glycolysis, as confirmed by coexpression of phosphorylated-AMPK and GLUT1. These findings underscore a unique role for redox signaling by GPx2 dysregulation in breast cancer, underlying tumor heterogeneity, leading to metabolic plasticity and malignant progression.
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Neoplasias de la Mama/metabolismo , Plasticidad de la Célula/fisiología , Glutatión Peroxidasa/metabolismo , Animales , Línea Celular Tumoral , Femenino , Glutatión Peroxidasa/genética , Glutatión Peroxidasa/fisiología , Glucólisis , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Metabolismo/fisiología , Ratones , Ratones Desnudos , Neovascularización Patológica/genética , Oxidación-Reducción , Fosforilación Oxidativa , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Electroreduction of nitrate/nitrite to high-value-added products, including NH2OH, is an important way to achieve sustainable production of green energy. However, this electrosynthesis of NH2OH still suffers from poor selectivity due to the various competing reactions. Here, we screen out Ni-N4 and Cu-N4 catalysts for highly efficient nitrite electroreduction to NH2OH by adopting density functional theory (DFT) calculations. DFT calculations reveal that the high selectivity of Ni-N4 and Cu-N4 is ascribed to their weak adsorption of *NH2OH and *NH intermediates, thereby preventing the further reduction of NH2OH. Moreover, using *NO as a model intermediate, we studied the relationship between the 3d orbital occupancy and adsorption strength of the intermediate. It is found that Ni-N4 and Cu-N4 with fully occupied dxz, dyz, and dz2 orbitals have poor adsorption of *NO intermediate. This work provides a new route for NH2OH synthesis and offers perspectives on the crucial factors in determining the catalytic selectivity.
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Quantum-dot light-emitting diodes (QLEDs), a kind of promising optoelectronic device, demonstrate potential superiority in next-generation display technology. Thermal cross-linked hole transport materials (HTMs) have been employed in solution-processed QLEDs due to their excellent thermal stability and solvent resistance, whereas the unbalanced charge injection and high cross-linking temperature of cross-linked HTMs can inhibit the efficiency of QLEDs and limit their application. Herein, a low-temperature cross-linked HTM of 4,4'-bis(3-(((4-vinylbenzyl)oxy)methyl)-9H-carbazol-9-yl)-1,1'-biphenyl (DV-CBP) with a flexible styrene side chain is introduced, which reduces the cross-linking temperature to 150 °C and enhances the hole mobility up to 1.01 × 10-3 cm2 V-1 s-1. More importantly, the maximum external quantum efficiency of 21.35% is successfully obtained on the basis of the DV-CBP as a cross-linked hole transport layer (HTL) for blue QLEDs. The low-temperature cross-linked high-mobility HTL using flexible side chains could be an excellent alternative for future HTL development.
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Circular RNA (CircRNA)-microRNA (miRNA) interaction (CMI) is an important model for the regulation of biological processes by non-coding RNA (ncRNA), which provides a new perspective for the study of human complex diseases. However, the existing CMI prediction models mainly rely on the nearest neighbor structure in the biological network, ignoring the molecular network topology, so it is difficult to improve the prediction performance. In this paper, we proposed a new CMI prediction method, BEROLECMI, which uses molecular sequence attributes, molecular self-similarity, and biological network topology to define the specific role feature representation for molecules to infer the new CMI. BEROLECMI effectively makes up for the lack of network topology in the CMI prediction model and achieves the highest prediction performance in three commonly used data sets. In the case study, 14 of the 15 pairs of unknown CMIs were correctly predicted.
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Biología Computacional , MicroARNs , ARN Circular , MicroARNs/genética , MicroARNs/metabolismo , MicroARNs/química , ARN Circular/genética , ARN Circular/metabolismo , Humanos , Biología Computacional/métodos , ARN/química , ARN/genética , ARN/metabolismo , Algoritmos , Redes Reguladoras de GenesRESUMEN
The N6-methyladenosine (m6A) modification possesses new and essential roles in tumor initiation and progression by regulating mRNA biology. However, the role of aberrant m6A regulation in nasopharyngeal carcinoma (NPC) remains unclear. Here, through comprehensive analyses of NPC cohorts from the GEO database and our internal cohort, we identified that VIRMA, an m6A writer, is significantly upregulated in NPC and plays an essential role in tumorigenesis and metastasis of NPC, both in vitro and in vivo. High VIRMA expression served as a prognostic biomarker and was associated with poor outcomes in patients with NPC. Mechanistically, VIRMA mediated the m6A methylation of E2F7 3'-UTR, then IGF2BP2 bound, and maintained the stability of E2F7 mRNA. An integrative high-throughput sequencing approach revealed that E2F7 drives a unique transcriptome distinct from the classical E2F family in NPC, which functioned as an oncogenic transcriptional activator. E2F7 cooperated with CBFB-recruited RUNX1 in a non-canonical manner to transactivate ITGA2, ITGA5, and NTRK1, strengthening Akt signaling-induced tumor-promoting effect.
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Carcinogénesis , Factor de Transcripción E2F7 , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Proteínas de Unión al ARN , Humanos , Carcinogénesis/genética , Transformación Celular Neoplásica , Factor de Transcripción E2F7/genética , Factor de Transcripción E2F7/metabolismo , Carcinoma Nasofaríngeo/metabolismo , Carcinoma Nasofaríngeo/patología , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/patología , ARN Mensajero/genética , Proteínas de Unión al ARN/metabolismo , Regulación hacia ArribaRESUMEN
Dysregulation of long noncoding RNAs (lncRNAs) contributes to tumorigenesis by modulating specific cancer-related pathways, but the roles of N6-methyladenosine (m6A)-enriched lncRNAs and underlying mechanisms remain elusive in nasopharyngeal carcinoma (NPC). Here, we reanalyzed the previous genome-wide analysis of lncRNA profiles in 18 pairs of NPC and normal tissues as well as in ten paired samples from NPC with or without post-treatment metastases. We discerned that an oncogenic m6A-enriched lncRNA, LINC00839, which was substantially upregulated in NPC and correlated with poor clinical prognosis, promoted NPC growth and metastasis both in vitro and in vivo. Mechanistically, by using RNA pull-down assay combined with mass spectrometry, we found that LINC00839 interacted directly with the transcription factor, TATA-box binding protein associated factor (TAF15). Besides, chromatin immunoprecipitation and dual-luciferase report assays demonstrated that LINC00839 coordinated the recruitment of TAF15 to the promoter region of amine oxidase copper-containing 1 (AOC1), which encodes a secreted glycoprotein playing vital roles in various cancers, thereby activating AOC1 transcription in trans. In this study, potential effects of AOC1 in NPC progression were first proposed. Moreover, ectopic expression of AOC1 partially rescued the inhibitory effect of downregulation of LINC00839 in NPC. Furthermore, we showed that silencing vir-like m6A methyltransferase-associated (VIRMA) and insulin-like growth factor 2 mRNA-binding proteins 1 (IGF2BP1) attenuated the expression level and RNA stability of LINC00839 in an m6A-dependent manner. Taken together, our study unveils a novel oncogenic VIRMA/IGF2BP1-LINC00839-TAF15-AOC1 axis and highlights the significance and prognostic value of LINC00839 expression in NPC carcinogenesis.