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1.
Cell ; 166(2): 492-505, 2016 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-27419873

RESUMO

The epigenome orchestrates genome accessibility, functionality, and three-dimensional structure. Because epigenetic variation can impact transcription and thus phenotypes, it may contribute to adaptation. Here, we report 1,107 high-quality single-base resolution methylomes and 1,203 transcriptomes from the 1001 Genomes collection of Arabidopsis thaliana. Although the genetic basis of methylation variation is highly complex, geographic origin is a major predictor of genome-wide DNA methylation levels and of altered gene expression caused by epialleles. Comparison to cistrome and epicistrome datasets identifies associations between transcription factor binding sites, methylation, nucleotide variation, and co-expression modules. Physical maps for nine of the most diverse genomes reveal how transposons and other structural variants shape the epigenome, with dramatic effects on immunity genes. The 1001 Epigenomes Project provides a comprehensive resource for understanding how variation in DNA methylation contributes to molecular and non-molecular phenotypes in natural populations of the most studied model plant.


Assuntos
Arabidopsis/genética , Epigênese Genética , Metilação de DNA , Epigenômica , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Transcriptoma
2.
Nature ; 624(7991): 366-377, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38092913

RESUMO

Cytosine DNA methylation is essential in brain development and is implicated in various neurological disorders. Understanding DNA methylation diversity across the entire brain in a spatial context is fundamental for a complete molecular atlas of brain cell types and their gene regulatory landscapes. Here we used single-nucleus methylome sequencing (snmC-seq3) and multi-omic sequencing (snm3C-seq)1 technologies to generate 301,626 methylomes and 176,003 chromatin conformation-methylome joint profiles from 117 dissected regions throughout the adult mouse brain. Using iterative clustering and integrating with companion whole-brain transcriptome and chromatin accessibility datasets, we constructed a methylation-based cell taxonomy with 4,673 cell groups and 274 cross-modality-annotated subclasses. We identified 2.6 million differentially methylated regions across the genome that represent potential gene regulation elements. Notably, we observed spatial cytosine methylation patterns on both genes and regulatory elements in cell types within and across brain regions. Brain-wide spatial transcriptomics data validated the association of spatial epigenetic diversity with transcription and improved the anatomical mapping of our epigenetic datasets. Furthermore, chromatin conformation diversities occurred in important neuronal genes and were highly associated with DNA methylation and transcription changes. Brain-wide cell-type comparisons enabled the construction of regulatory networks that incorporate transcription factors, regulatory elements and their potential downstream gene targets. Finally, intragenic DNA methylation and chromatin conformation patterns predicted alternative gene isoform expression observed in a whole-brain SMART-seq2 dataset. Our study establishes a brain-wide, single-cell DNA methylome and 3D multi-omic atlas and provides a valuable resource for comprehending the cellular-spatial and regulatory genome diversity of the mouse brain.


Assuntos
Encéfalo , Metilação de DNA , Epigenoma , Multiômica , Análise de Célula Única , Animais , Camundongos , Encéfalo/citologia , Encéfalo/metabolismo , Cromatina/química , Cromatina/genética , Cromatina/metabolismo , Citosina/metabolismo , Conjuntos de Dados como Assunto , Fatores de Transcrição/metabolismo , Transcrição Gênica
3.
Cell ; 153(5): 1134-48, 2013 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-23664764

RESUMO

Epigenetic mechanisms have been proposed to play crucial roles in mammalian development, but their precise functions are only partially understood. To investigate epigenetic regulation of embryonic development, we differentiated human embryonic stem cells into mesendoderm, neural progenitor cells, trophoblast-like cells, and mesenchymal stem cells and systematically characterized DNA methylation, chromatin modifications, and the transcriptome in each lineage. We found that promoters that are active in early developmental stages tend to be CG rich and mainly engage H3K27me3 upon silencing in nonexpressing lineages. By contrast, promoters for genes expressed preferentially at later stages are often CG poor and primarily employ DNA methylation upon repression. Interestingly, the early developmental regulatory genes are often located in large genomic domains that are generally devoid of DNA methylation in most lineages, which we termed DNA methylation valleys (DMVs). Our results suggest that distinct epigenetic mechanisms regulate early and late stages of ES cell differentiation.


Assuntos
Metilação de DNA , Células-Tronco Embrionárias/metabolismo , Epigenômica , Regulação da Expressão Gênica no Desenvolvimento , Animais , Diferenciação Celular , Cromatina/metabolismo , Ilhas de CpG , Células-Tronco Embrionárias/citologia , Histonas/metabolismo , Humanos , Metilação , Neoplasias/genética , Regiões Promotoras Genéticas , Peixe-Zebra/embriologia
4.
Nature ; 598(7879): 120-128, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34616061

RESUMO

Mammalian brain cells show remarkable diversity in gene expression, anatomy and function, yet the regulatory DNA landscape underlying this extensive heterogeneity is poorly understood. Here we carry out a comprehensive assessment of the epigenomes of mouse brain cell types by applying single-nucleus DNA methylation sequencing1,2 to profile 103,982 nuclei (including 95,815 neurons and 8,167 non-neuronal cells) from 45 regions of the mouse cortex, hippocampus, striatum, pallidum and olfactory areas. We identified 161 cell clusters with distinct spatial locations and projection targets. We constructed taxonomies of these epigenetic types, annotated with signature genes, regulatory elements and transcription factors. These features indicate the potential regulatory landscape supporting the assignment of putative cell types and reveal repetitive usage of regulators in excitatory and inhibitory cells for determining subtypes. The DNA methylation landscape of excitatory neurons in the cortex and hippocampus varied continuously along spatial gradients. Using this deep dataset, we constructed an artificial neural network model that precisely predicts single neuron cell-type identity and brain area spatial location. Integration of high-resolution DNA methylomes with single-nucleus chromatin accessibility data3 enabled prediction of high-confidence enhancer-gene interactions for all identified cell types, which were subsequently validated by cell-type-specific chromatin conformation capture experiments4. By combining multi-omic datasets (DNA methylation, chromatin contacts, and open chromatin) from single nuclei and annotating the regulatory genome of hundreds of cell types in the mouse brain, our DNA methylation atlas establishes the epigenetic basis for neuronal diversity and spatial organization throughout the mouse cerebrum.


Assuntos
Encéfalo/citologia , Metilação de DNA , Epigenoma , Epigenômica , Neurônios/classificação , Neurônios/metabolismo , Análise de Célula Única , Animais , Atlas como Assunto , Encéfalo/metabolismo , Cromatina/química , Cromatina/genética , Cromatina/metabolismo , Citosina/química , Citosina/metabolismo , Conjuntos de Dados como Assunto , Giro Denteado/citologia , Elementos Facilitadores Genéticos/genética , Perfilação da Expressão Gênica , Hipocampo/citologia , Hipocampo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Biológicos , Vias Neurais , Neurônios/citologia
5.
Brief Bioinform ; 25(4)2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38980371

RESUMO

Accurate prediction of protein-ligand binding affinity (PLA) is important for drug discovery. Recent advances in applying graph neural networks have shown great potential for PLA prediction. However, existing methods usually neglect the geometric information (i.e. bond angles), leading to difficulties in accurately distinguishing different molecular structures. In addition, these methods also pose limitations in representing the binding process of protein-ligand complexes. To address these issues, we propose a novel geometry-enhanced mid-fusion network, named GEMF, to learn comprehensive molecular geometry and interaction patterns. Specifically, the GEMF consists of a graph embedding layer, a message passing phase, and a multi-scale fusion module. GEMF can effectively represent protein-ligand complexes as graphs, with graph embeddings based on physicochemical and geometric properties. Moreover, our dual-stream message passing framework models both covalent and non-covalent interactions. In particular, the edge-update mechanism, which is based on line graphs, can fuse both distance and angle information in the covalent branch. In addition, the communication branch consisting of multiple heterogeneous interaction modules is developed to learn intricate interaction patterns. Finally, we fuse the multi-scale features from the covalent, non-covalent, and heterogeneous interaction branches. The extensive experimental results on several benchmarks demonstrate the superiority of GEMF compared with other state-of-the-art methods.


Assuntos
Redes Neurais de Computação , Ligação Proteica , Proteínas , Proteínas/química , Proteínas/metabolismo , Ligantes , Algoritmos , Biologia Computacional/métodos , Descoberta de Drogas/métodos
6.
Nature ; 583(7818): 752-759, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32728242

RESUMO

Cytosine DNA methylation is essential for mammalian development but understanding of its spatiotemporal distribution in the developing embryo remains limited1,2. Here, as part of the mouse Encyclopedia of DNA Elements (ENCODE) project, we profiled 168 methylomes from 12 mouse tissues or organs at 9 developmental stages from embryogenesis to adulthood. We identified 1,808,810 genomic regions that showed variations in CG methylation by comparing the methylomes of different tissues or organs from different developmental stages. These DNA elements predominantly lose CG methylation during fetal development, whereas the trend is reversed after birth. During late stages of fetal development, non-CG methylation accumulated within the bodies of key developmental transcription factor genes, coinciding with their transcriptional repression. Integration of genome-wide DNA methylation, histone modification and chromatin accessibility data enabled us to predict 461,141 putative developmental tissue-specific enhancers, the human orthologues of which were enriched for disease-associated genetic variants. These spatiotemporal epigenome maps provide a resource for studies of gene regulation during tissue or organ progression, and a starting point for investigating regulatory elements that are involved in human developmental disorders.


Assuntos
Metilação de DNA , Epigenoma , Feto/embriologia , Feto/metabolismo , Animais , Animais Recém-Nascidos , Cromatina/genética , Cromatina/metabolismo , Doença/genética , Regulação para Baixo , Elementos Facilitadores Genéticos/genética , Repressão Epigenética , Feminino , Inativação Gênica , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Modelos Animais , Anotação de Sequência Molecular , Polimorfismo de Nucleotídeo Único , Análise Espaço-Temporal
7.
Brief Bioinform ; 22(3)2021 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-32459334

RESUMO

In recent years, high-throughput experimental techniques have significantly enhanced the accuracy and coverage of protein-protein interaction identification, including human-pathogen protein-protein interactions (HP-PPIs). Despite this progress, experimental methods are, in general, expensive in terms of both time and labour costs, especially considering that there are enormous amounts of potential protein-interacting partners. Developing computational methods to predict interactions between human and bacteria pathogen has thus become critical and meaningful, in both facilitating the detection of interactions and mining incomplete interaction maps. In this paper, we present a systematic evaluation of machine learning-based computational methods for human-bacterium protein-protein interactions (HB-PPIs). We first reviewed a vast number of publicly available databases of HP-PPIs and then critically evaluate the availability of these databases. Benefitting from its well-structured nature, we subsequently preprocess the data and identified six bacterium pathogens that could be used to study bacterium subjects in which a human was the host. Additionally, we thoroughly reviewed the literature on 'host-pathogen interactions' whereby existing models were summarized that we used to jointly study the impact of different feature representation algorithms and evaluate the performance of existing machine learning computational models. Owing to the abundance of sequence information and the limited scale of other protein-related information, we adopted the primary protocol from the literature and dedicated our analysis to a comprehensive assessment of sequence information and machine learning models. A systematic evaluation of machine learning models and a wide range of feature representation algorithms based on sequence information are presented as a comparison survey towards the prediction performance evaluation of HB-PPIs.


Assuntos
Interações Hospedeiro-Patógeno , Aprendizado de Máquina , Mapeamento de Interação de Proteínas/métodos , Algoritmos , Biologia Computacional/métodos , Humanos
8.
Small ; 18(44): e2203976, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36089671

RESUMO

Metallic Bi, as an alloying-type anode material, has demonstrated tremendous potential for practical application of potassium-ion batteries. However, the giant volume expansion, severe structure pulverization, and sluggish dynamics of Bi-based materials result in unsatisfied rate performance and unstable cycling stability. Here, 2D bismuth@N-doped carbon sheets with BiOC bond and internal void space (2D Bi@NOC) are successfully fabricated via a self-template strategy to address these issues, which own ultrafast electrochemical kinetics and impressive long-term cycling stability for delivering an admirable capacity of 341.7 mAh g-1 after 1000 cycles at 10 A g-1 and impressive rate capability of 220.6 mAh g-1 at 50 A g-1 . Particularly, the in situ transmission electron microscopy observations visualize the real-time alloying/dealloying process and reveal that plastic carbon shell and void space can availably relieve dramatic volume stress and powerfully maintain structural integrity. Density functional theory calculation and ultraviolet photoelectron spectroscopy test certify that the robust BiOC bond is thermodynamically and kinetically beneficial for adsorption/diffusion of K+ . This work will light on designing advanced high-performance energy materials and provide important evidence for understanding the energy storage mechanism of alloy-based materials.

9.
PLoS Genet ; 15(1): e1007819, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30657772

RESUMO

The bacterium Agrobacterium tumefaciens has been the workhorse in plant genome engineering. Customized replacement of native tumor-inducing (Ti) plasmid elements enabled insertion of a sequence of interest called Transfer-DNA (T-DNA) into any plant genome. Although these transfer mechanisms are well understood, detailed understanding of structure and epigenomic status of insertion events was limited by current technologies. Here we applied two single-molecule technologies and analyzed Arabidopsis thaliana lines from three widely used T-DNA insertion collections (SALK, SAIL and WISC). Optical maps for four randomly selected T-DNA lines revealed between one and seven insertions/rearrangements, and the length of individual insertions from 27 to 236 kilobases. De novo nanopore sequencing-based assemblies for two segregating lines partially resolved T-DNA structures and revealed multiple translocations and exchange of chromosome arm ends. For the current TAIR10 reference genome, nanopore contigs corrected 83% of non-centromeric misassemblies. The unprecedented contiguous nucleotide-level resolution enabled an in-depth study of the epigenome at T-DNA insertion sites. SALK_059379 line T-DNA insertions were enriched for 24nt small interfering RNAs (siRNA) and dense cytosine DNA methylation, resulting in transgene silencing via the RNA-directed DNA methylation pathway. In contrast, SAIL_232 line T-DNA insertions are predominantly targeted by 21/22nt siRNAs, with DNA methylation and silencing limited to a reporter, but not the resistance gene. Additionally, we profiled the H3K4me3, H3K27me3 and H2A.Z chromatin environments around T-DNA insertions using ChIP-seq in SALK_059379, SAIL_232 and five additional T-DNA lines. We discovered various effect s ranging from complete loss of chromatin marks to the de novo incorporation of H2A.Z and trimethylation of H3K4 and H3K27 around the T-DNA integration sites. This study provides new insights into the structural impact of inserting foreign fragments into plant genomes and demonstrates the utility of state-of-the-art long-range sequencing technologies to rapidly identify unanticipated genomic changes.


Assuntos
Metilação de DNA/genética , DNA Bacteriano/genética , DNA de Plantas/genética , Epigênese Genética/genética , Agrobacterium tumefaciens/genética , Arabidopsis/genética , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Genoma de Planta/genética , Mutagênese Insercional/genética , Plasmídeos Indutores de Tumores em Plantas/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Transformação Genética
10.
Cost Eff Resour Alloc ; 19(1): 51, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34399783

RESUMO

BACKGROUND: Rapid economic growth in China has resulted in a commensurate increase in energy consumption, which in turn has seen an increase in environmental pollution problems. Past research has tended to focus on energy and environmental efficiency analyses and has rarely examined the media influence on environmental protection efforts. Further, most studies have used static models and ignored the dynamic changes over time. METHODS: To go some way to filling this research gap, this study developed a modified undesirable Dynamic DEA model that included air quality index (AQI) and CO2 indicators to explore the relationships between energy, the environment, and media report efficiencies in 31 Chinese cities from 2013 to 2016. RESULTS: It was found that: (1) Chongqing, Guangzhou, Nanjing and Shanghai had efficiencies of 1, but Lanzhou, Shijiazhuang, Taiyuan, Xining and Yinchuan needed significant improvements; (2) Chongqing, Guangzhou, Kunming, Nanning and Shanghai had relatively high media efficiencies, but the other cities had low efficiencies and required improvements; (3) the CO2 emissions efficiencies in most cities were better than the air quality index efficiencies; and 4. the media reports in most cities were found to have a more positive impact on the CO2 emissions efficiency than on the AQI efficiency. CONCLUSIONS: Environmental awareness enhances civilian health and promotes economic growth. Therefore, as the news media should be responsible for promoting environmental protection, they need to increase their environmental pollution coverage. It was found that the environmental pollution media report quality and especially air pollution reports needed improvements, and greater media coverage on environmental pollution and awareness was needed.

11.
Nature ; 523(7559): 212-6, 2015 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-26030523

RESUMO

Understanding the diversity of human tissues is fundamental to disease and requires linking genetic information, which is identical in most of an individual's cells, with epigenetic mechanisms that could have tissue-specific roles. Surveys of DNA methylation in human tissues have established a complex landscape including both tissue-specific and invariant methylation patterns. Here we report high coverage methylomes that catalogue cytosine methylation in all contexts for the major human organ systems, integrated with matched transcriptomes and genomic sequence. By combining these diverse data types with each individuals' phased genome, we identified widespread tissue-specific differential CG methylation (mCG), partially methylated domains, allele-specific methylation and transcription, and the unexpected presence of non-CG methylation (mCH) in almost all human tissues. mCH correlated with tissue-specific functions, and using this mark, we made novel predictions of genes that escape X-chromosome inactivation in specific tissues. Overall, DNA methylation in several genomic contexts varies substantially among human tissues.


Assuntos
Metilação de DNA , Epigênese Genética , Fatores Etários , Alelos , Mapeamento Cromossômico , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Variação Genética , Humanos , Masculino , Especificidade de Órgãos
12.
Cancer Sci ; 110(11): 3553-3564, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31464032

RESUMO

To determine the therapeutic efficacy and safety of risk-adapted stereotactic body radiation therapy (SBRT) schedules for patients with early-stage central and ultra-central inoperable non-small cell lung cancer. From 2006 to 2015, 80 inoperable T1-2N0M0 NSCLC patients were treated with two median dose levels: 60 Gy in six fractions (range, 48-60 Gy in 4-8 fractions) prescribed to the 74% isodose line (range, 58%-79%) for central lesions (ie within 2 cm of, but not abutting, the proximal bronchial tree; n = 43), and 56 Gy in seven fractions (range, 48-60 Gy in 5-10 fractions) prescribed to the 74% isodose line (range, 60%-80%) for ultra-central lesions (ie abutting the proximal bronchial tree; n = 37) on consecutive days. Primary endpoint was overall survival (OS); secondary endpoints included progression-free survival (PFS), tumor local control rate (LC), and toxicity. Median OS and PFS were 64.47 and 32.10 months (respectively) for ultra-central patients, and not reached for central patients. Median time to local failure, regional failure, and any distant failures for central versus ultra-central lesions were: 27.37 versus 26.07 months, 20.90 versus 12.53 months, and 20.85 versus 15.53 months, respectively, all P < .05. Multivariate analyses showed that tumor categorization (ultra-central) and planning target volume ≥52.76 mL were poor prognostic factors of OS, PFS, and LC, respectively (all P < .05). There was one grade 5 toxicity; all other toxicities were grade 1-2. Our results showed that ultra-central tumors have a poor OS, PFS, and LC compared with central patients because of the use of risk-adapted SBRT schedules that allow for equal and favorable toxicity profiles.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/radioterapia , Radiocirurgia/métodos , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Fracionamento da Dose de Radiação , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Intervalo Livre de Progressão , Radiocirurgia/efeitos adversos , Estudos Retrospectivos , Fatores de Tempo , Falha de Tratamento
13.
Nature ; 495(7440): 193-8, 2013 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-23467092

RESUMO

Natural epigenetic variation provides a source for the generation of phenotypic diversity, but to understand its contribution to such diversity, its interaction with genetic variation requires further investigation. Here we report population-wide DNA sequencing of genomes, transcriptomes and methylomes of wild Arabidopsis thaliana accessions. Single cytosine methylation polymorphisms are not linked to genotype. However, the rate of linkage disequilibrium decay amongst differentially methylated regions targeted by RNA-directed DNA methylation is similar to the rate for single nucleotide polymorphisms. Association analyses of these RNA-directed DNA methylation regions with genetic variants identified thousands of methylation quantitative trait loci, which revealed the population estimate of genetically dependent methylation variation. Analysis of invariably methylated transposons and genes across this population indicates that loci targeted by RNA-directed DNA methylation are epigenetically activated in pollen and seeds, which facilitates proper development of these structures.


Assuntos
Arabidopsis/genética , Epigênese Genética/genética , Variação Genética/genética , Genoma de Planta/genética , Metilação de DNA/genética , Elementos de DNA Transponíveis/genética , Epigenômica , Desequilíbrio de Ligação/genética , Pólen/genética , Polimorfismo Genético/genética , Locos de Características Quantitativas , RNA Mensageiro/análise , RNA Mensageiro/genética , RNA de Plantas/genética , Sementes/genética
14.
Proc Natl Acad Sci U S A ; 113(29): E4238-47, 2016 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-27357687

RESUMO

Protein microarrays enable investigation of diverse biochemical properties for thousands of proteins in a single experiment, an unparalleled capacity. Using a high-density system called HaloTag nucleic acid programmable protein array (HaloTag-NAPPA), we created high-density protein arrays comprising 12,000 Arabidopsis ORFs. We used these arrays to query protein-protein interactions for a set of 38 transcription factors and transcriptional regulators (TFs) that function in diverse plant hormone regulatory pathways. The resulting transcription factor interactome network, TF-NAPPA, contains thousands of novel interactions. Validation in a benchmarked in vitro pull-down assay revealed that a random subset of TF-NAPPA validated at the same rate of 64% as a positive reference set of literature-curated interactions. Moreover, using a bimolecular fluorescence complementation (BiFC) assay, we confirmed in planta several interactions of biological interest and determined the interaction localizations for seven pairs. The application of HaloTag-NAPPA technology to plant hormone signaling pathways allowed the identification of many novel transcription factor-protein interactions and led to the development of a proteome-wide plant hormone TF interactome network.


Assuntos
Proteínas de Arabidopsis/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Arabidopsis/metabolismo , Análise Serial de Proteínas , Mapeamento de Interação de Proteínas
16.
Heliyon ; 10(7): e28256, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38596030

RESUMO

Glioma is the leading cancer of the central nervous system (CNS). The efficacy of glioma treatment is significantly hindered by the presence of the blood-brain barrier (BBB) and blood-brain tumour barrier (BBTB), which prevent most drugs from entering the brain and tumours. Hence, we established a novel drug delivery nanosystem of brain tumour-targeting that could self-assemble the method using an amphiphilic Zein protein isolated from corn. Zein's amphiphilicity prompted it to self-assembled into NPs, efficiently containing TMZ. This allowed us to investigate temozolomide (TMZ) for glioblastoma (GBM) treatment. To construct TMZ-encapsulated NPs (TMZ@RVG-Zein NPs), the NPs' Zein was clocked to rabies virus glycoprotein 29 (RVG29). To verify that the NPs could penetrate the BBB and precisely target and kill the GBM cancer cell line, in vitro studies were performed. The process of NPs penetrating cancer cell membranes was investigated using enzyme-linked immunosorbent assays (ELISAs) to measure the expressions of nicotinic acetylcholine receptors (nAChRs) on the U87 cell line. Therefore, effective targeted brain cancer treatment is possible by forming NP clocks, a cell-penetrating natural Zein protein with an RVG29. These NPs can penetrate the blood-brain barrier (BBB) and enter the glioblastoma (U87) cell line to release TMZ. These NPs have a distinct cocktail of biocompatibility and brain-targeting abilities, making them ideal for involving brain diseases.

17.
ACS Appl Mater Interfaces ; 15(10): 12976-12985, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36862658

RESUMO

As the most promising candidate for lithium-ion batteries (LIBs), the electrochemical performance of sodium-ion batteries (SIBs) is highly dependent on the electrode materials. Copper selenides have established themselves as potential anode materials for SIBs due to their high theoretical capacity and good conductivity. However, the poor rate performance and fast capacity fading are the major challenges to their practical application in SIBs. Herein, single-crystalline CuSe2 nanocubes (CuSe2 NCs) are successfully synthesized via a solvothermal method. As an anode of SIBs, the CuSe2 NCs render an almost 100% initial Coulombic efficiency, an outstanding long cycle life, e.g., 380 mA h g-1 after 1700 cycles at 10 A g-1, and an unprecedented rate performance of 344 mA h g-1 at 50 A g-1. Ex situ X-ray diffraction (XRD) patterns reveal the crystalline transformation of energy-storage materials, and the density functional theory (DFT) conclusion suggests that fast and stable ion diffusion kinetics enhances their electrochemical performance upon sodiation/desodiaton. The investigation into the mechanism provides a theoretical basis for subsequent practical applications.

18.
Science ; 382(6667): eadf5357, 2023 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-37824674

RESUMO

Delineating the gene-regulatory programs underlying complex cell types is fundamental for understanding brain function in health and disease. Here, we comprehensively examined human brain cell epigenomes by probing DNA methylation and chromatin conformation at single-cell resolution in 517 thousand cells (399 thousand neurons and 118 thousand non-neurons) from 46 regions of three adult male brains. We identified 188 cell types and characterized their molecular signatures. Integrative analyses revealed concordant changes in DNA methylation, chromatin accessibility, chromatin organization, and gene expression across cell types, cortical areas, and basal ganglia structures. We further developed single-cell methylation barcodes that reliably predict brain cell types using the methylation status of select genomic sites. This multimodal epigenomic brain cell atlas provides new insights into the complexity of cell-type-specific gene regulation in adult human brains.


Assuntos
Encéfalo , Metilação de DNA , Epigênese Genética , Adulto , Humanos , Masculino , Encéfalo/citologia , Encéfalo/metabolismo , Cromatina/metabolismo , Genoma Humano , Análise de Célula Única , Imageamento Tridimensional , Atlas como Assunto
19.
bioRxiv ; 2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37131654

RESUMO

Cytosine DNA methylation is essential in brain development and has been implicated in various neurological disorders. A comprehensive understanding of DNA methylation diversity across the entire brain in the context of the brain's 3D spatial organization is essential for building a complete molecular atlas of brain cell types and understanding their gene regulatory landscapes. To this end, we employed optimized single-nucleus methylome (snmC-seq3) and multi-omic (snm3C-seq1) sequencing technologies to generate 301,626 methylomes and 176,003 chromatin conformation/methylome joint profiles from 117 dissected regions throughout the adult mouse brain. Using iterative clustering and integrating with companion whole-brain transcriptome and chromatin accessibility datasets, we constructed a methylation-based cell type taxonomy that contains 4,673 cell groups and 261 cross-modality-annotated subclasses. We identified millions of differentially methylated regions (DMRs) across the genome, representing potential gene regulation elements. Notably, we observed spatial cytosine methylation patterns on both genes and regulatory elements in cell types within and across brain regions. Brain-wide multiplexed error-robust fluorescence in situ hybridization (MERFISH2) data validated the association of this spatial epigenetic diversity with transcription and allowed the mapping of the DNA methylation and topology information into anatomical structures more precisely than our dissections. Furthermore, multi-scale chromatin conformation diversities occur in important neuronal genes, highly associated with DNA methylation and transcription changes. Brain-wide cell type comparison allowed us to build a regulatory model for each gene, linking transcription factors, DMRs, chromatin contacts, and downstream genes to establish regulatory networks. Finally, intragenic DNA methylation and chromatin conformation patterns predicted alternative gene isoform expression observed in a companion whole-brain SMART-seq3 dataset. Our study establishes the first brain-wide, single-cell resolution DNA methylome and 3D multi-omic atlas, providing an unparalleled resource for comprehending the mouse brain's cellular-spatial and regulatory genome diversity.

20.
bioRxiv ; 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37425926

RESUMO

Variations in DNA methylation patterns in human tissues have been linked to various environmental exposures and infections. Here, we identified the DNA methylation signatures associated with multiple exposures in nine major immune cell types derived from peripheral blood mononuclear cells (PBMCs) at single-cell resolution. We performed methylome sequencing on 111,180 immune cells obtained from 112 individuals who were exposed to different viruses, bacteria, or chemicals. Our analysis revealed 790,662 differentially methylated regions (DMRs) associated with these exposures, which are mostly individual CpG sites. Additionally, we integrated methylation and ATAC-seq data from same samples and found strong correlations between the two modalities. However, the epigenomic remodeling in these two modalities are complementary. Finally, we identified the minimum set of DMRs that can predict exposures. Overall, our study provides the first comprehensive dataset of single immune cell methylation profiles, along with unique methylation biomarkers for various biological and chemical exposures.

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