Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 36
Filtrar
1.
Mol Cell ; 81(16): 3368-3385.e9, 2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-34375583

RESUMO

The mechanistic understanding of nascent RNAs in transcriptional control remains limited. Here, by a high sensitivity method methylation-inscribed nascent transcripts sequencing (MINT-seq), we characterized the landscapes of N6-methyladenosine (m6A) on nascent RNAs. We uncover heavy but selective m6A deposition on nascent RNAs produced by transcription regulatory elements, including promoter upstream antisense RNAs and enhancer RNAs (eRNAs), which positively correlates with their length, inclusion of m6A motif, and RNA abundances. m6A-eRNAs mark highly active enhancers, where they recruit nuclear m6A reader YTHDC1 to phase separate into liquid-like condensates, in a manner dependent on its C terminus intrinsically disordered region and arginine residues. The m6A-eRNA/YTHDC1 condensate co-mixes with and facilitates the formation of BRD4 coactivator condensate. Consequently, YTHDC1 depletion diminished BRD4 condensate and its recruitment to enhancers, resulting in inhibited enhancer and gene activation. We propose that chemical modifications of eRNAs together with reader proteins play broad roles in enhancer activation and gene transcriptional control.


Assuntos
Adenosina/análogos & derivados , Proteínas de Ciclo Celular/genética , Proteínas do Tecido Nervoso/genética , Fatores de Processamento de RNA/genética , RNA/genética , Fatores de Transcrição/genética , Adenosina/genética , Elementos Facilitadores Genéticos/genética , Regulação da Expressão Gênica/genética , Humanos , Metilação , Elementos Reguladores de Transcrição/genética , Ativação Transcricional/genética
2.
Nature ; 595(7869): 735-740, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34040254

RESUMO

The functional engagement between an enhancer and its target promoter ensures precise gene transcription1. Understanding the basis of promoter choice by enhancers has important implications for health and disease. Here we report that functional loss of a preferred promoter can release its partner enhancer to loop to and activate an alternative promoter (or alternative promoters) in the neighbourhood. We refer to this target-switching process as 'enhancer release and retargeting'. Genetic deletion, motif perturbation or mutation, and dCas9-mediated CTCF tethering reveal that promoter choice by an enhancer can be determined by the binding of CTCF at promoters, in a cohesin-dependent manner-consistent with a model of 'enhancer scanning' inside the contact domain. Promoter-associated CTCF shows a lower affinity than that at chromatin domain boundaries and often lacks a preferred motif orientation or a partnering CTCF at the cognate enhancer, suggesting properties distinct from boundary CTCF. Analyses of cancer mutations, data from the GTEx project and risk loci from genome-wide association studies, together with a focused CRISPR interference screen, reveal that enhancer release and retargeting represents an overlooked mechanism that underlies the activation of disease-susceptibility genes, as exemplified by a risk locus for Parkinson's disease (NUCKS1-RAB7L1) and three loci associated with cancer (CLPTM1L-TERT, ZCCHC7-PAX5 and PVT1-MYC).


Assuntos
Fator de Ligação a CCCTC/genética , Elementos Facilitadores Genéticos , Predisposição Genética para Doença , Regiões Promotoras Genéticas , Sistemas CRISPR-Cas , Proteínas de Ciclo Celular/genética , Células Cultivadas , Cromatina , Proteínas Cromossômicas não Histona/genética , Deleção de Genes , Regulação Neoplásica da Expressão Gênica , Estudo de Associação Genômica Ampla , Humanos , Células MCF-7 , Neoplasias/genética , Células-Tronco Neurais , Oncogenes , Doença de Parkinson/genética , Coesinas
3.
Cell Commun Signal ; 21(1): 242, 2023 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-37723559

RESUMO

BACKGROUND: Cancer-associated fibroblasts (CAFs) are critically involved in tumor progression by maintaining extracellular mesenchyma (ECM) production and improving tumor development. Cyclooxygenase-2 (COX-2) has been proved to promote ECM formation and tumor progression. However, the mechanisms of COX-2 mediated CAFs activation have not yet been elucidated. Therefore, we conducted this study to identify the effects and mechanisms of COX-2 underlying CAFs activation by tumor-derived exosomal miRNAs in lung adenocarcinoma (LUAD) progression. METHODS: As measures of CAFs activation, the expressions of fibroblasts activated protein-1 (FAP-1) and α-smooth muscle actin (α-SMA), the main CAFs markers, were detected by Western blotting and Immunohistochemistry. And the expression of Fibronectin (FN1) was used to analyze ECM production by CAFs. The exosomes were extracted by ultracentrifugation and exo-miRNAs were detected by qRT-PCR. Herein, we further elucidated the implicated mechanisms using online prediction software, luciferase reporter assays, co-immunoprecipitation, and experimental animal models. RESULTS: In vivo, a positive correlation was observed between the COX-2 expression levels in parenchyma and α-SMA/FN1 expression levels in mesenchyma in LUAD. However, PGE2, one of major product of COX-2, did not affect CAFs activation directly. COX-2 overexpression increased exo-miR-1290 expression, which promoted CAFs activation. Furthermore, Cullin3 (CUL3), a potential target of miR-1290, was found to suppress COX-2/exo-miR-1290-mediated CAFs activation and ECM production, consequently impeding tumor progression. CUL3 is identified to induce the Nuclear Factor Erythroid 2-Related Factor 2 (NFE2L2, Nrf2) ubiquitination and degradation, while exo-miR-1290 can prevent Nrf2 ubiquitination and increase its protein stability by targeting CUL3. Additionally, we identified that Nrf2 is direcctly bound with promoters of FAP-1 and FN1, which enhanced CAFs activation by promoting FAP-1 and FN1 transcription. CONCLUSIONS: Our data identify a new CAFs activation mechanism by exosomes derived from cancer cells that overexpress COX-2. Specifically, COX-2/exo-miR-1290/CUL3 is suggested as a novel signaling pathway for mediating CAFs activation and tumor progression in LUAD. Consequently, this finding suggests a novel strategy for cancer treatment that may tackle tumor progression in the future. Video Abstract.


Assuntos
Adenocarcinoma de Pulmão , Fibroblastos Associados a Câncer , Neoplasias Pulmonares , Animais , Ciclo-Oxigenase 2 , Fator 2 Relacionado a NF-E2 , Neoplasias Pulmonares/genética
4.
Nucleic Acids Res ; 48(5): 2621-2642, 2020 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-31863590

RESUMO

Transposable elements (TEs) comprise a large proportion of long non-coding RNAs (lncRNAs). Here, we employed CRISPR to delete a short interspersed nuclear element (SINE) in Malat1, a cancer-associated lncRNA, to investigate its significance in cellular physiology. We show that Malat1 with a SINE deletion forms diffuse nuclear speckles and is frequently translocated to the cytoplasm. SINE-deleted cells exhibit an activated unfolded protein response and PKR and markedly increased DNA damage and apoptosis caused by dysregulation of TDP-43 localization and formation of cytotoxic inclusions. TDP-43 binds stronger to Malat1 without the SINE and is likely 'hijacked' by cytoplasmic Malat1 to the cytoplasm, resulting in the depletion of nuclear TDP-43 and redistribution of TDP-43 binding to repetitive element transcripts and mRNAs encoding mitotic and nuclear-cytoplasmic regulators. The SINE promotes Malat1 nuclear retention by facilitating Malat1 binding to HNRNPK, a protein that drives RNA nuclear retention, potentially through direct interactions of the SINE with KHDRBS1 and TRA2A, which bind to HNRNPK. Losing these RNA-protein interactions due to the SINE deletion likely creates more available TDP-43 binding sites on Malat1 and subsequent TDP-43 aggregation. These results highlight the significance of lncRNA TEs in TDP-43 proteostasis with potential implications in both cancer and neurodegenerative diseases.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Proteostase/genética , RNA Longo não Codificante/genética , Elementos Nucleotídeos Curtos e Dispersos/genética , Apoptose , Linhagem Celular , Citoplasma/metabolismo , Dano ao DNA , Estresse do Retículo Endoplasmático , Ativação Enzimática , Dosagem de Genes , Ribonucleoproteínas Nucleares Heterogêneas Grupo K/metabolismo , Humanos , Mitose , Modelos Biológicos , Transporte Proteico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Deleção de Sequência/genética , eIF-2 Quinase
5.
PLoS Genet ; 11(2): e1004993, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25692300

RESUMO

Systematic characterization of hybrid incompatibility (HI) between related species remains the key to understanding speciation. The genetic basis of HI has been intensively studied in Drosophila species, but remains largely unknown in other species, including nematodes, which is mainly due to the lack of a sister species with which C. elegans can mate and produce viable progeny. The recent discovery of a C. briggsae sister species, C. nigoni, has opened up the possibility of dissecting the genetic basis of HI in nematode species. However, the paucity of dominant and visible marker prevents the efficient mapping of HI loci between the two species. To elucidate the genetic basis of speciation in nematode species, we first generated 96 chromosomally integrated GFP markers in the C. briggsae genome and mapped them into the defined locations by PCR and Next-Generation Sequencing (NGS). Aided by the marker, we backcrossed the GFP-associated C. briggsae genomic fragments into C. nigoni for at least 15 generations and produced 111 independent introgressions. The introgression fragments cover most of the C. briggsae genome. We finally dissected the patterns of HI by scoring the embryonic lethality, larval arrest, sex ratio and male sterility for each introgression line, through which we identified pervasive HI loci and produced a genome-wide landscape of HI between the two nematode species, the first of its type for any non-Drosophila species. The HI data not only provided insights into the genetic basis of speciation, but also established a framework for the possible cloning of HI loci between the two nematode species. Furthermore, the data on hybrids confirmed Haldane's rule and suggested the presence of a large X effect in terms of fertility between the two species. Importantly, this work opens a new avenue for studying speciation genetics between nematode species and allows parallel comparison of the HI with that in Drosophila and other species.


Assuntos
Caenorhabditis/genética , Especiação Genética , Hibridização Genética , Isolamento Reprodutivo , Animais , Drosophila/genética , Genoma , Proteínas de Fluorescência Verde , Sequenciamento de Nucleotídeos em Larga Escala , Especificidade da Espécie , Cromossomo X
6.
Mol Syst Biol ; 11(6): 814, 2015 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-26063786

RESUMO

Coordination of cell division timing is crucial for proper cell fate specification and tissue growth. However, the differential regulation of cell division timing across or within cell types during metazoan development remains poorly understood. To elucidate the systems-level genetic architecture coordinating division timing, we performed a high-content screening for genes whose depletion produced a significant reduction in the asynchrony of division between sister cells (ADS) compared to that of wild-type during Caenorhabditis elegans embryogenesis. We quantified division timing using 3D time-lapse imaging followed by computer-aided lineage analysis. A total of 822 genes were selected for perturbation based on their conservation and known roles in development. Surprisingly, we find that cell fate determinants are not only essential for establishing fate asymmetry, but also are imperative for setting the ADS regardless of cellular context, indicating a common genetic architecture used by both cellular processes. The fate determinants demonstrate either coupled or separate regulation between the two processes. The temporal coordination appears to facilitate cell migration during fate specification or tissue growth. Our quantitative dataset with cellular resolution provides a resource for future analyses of the genetic control of spatial and temporal coordination during metazoan development.


Assuntos
Proteínas de Caenorhabditis elegans/biossíntese , Diferenciação Celular/genética , Divisão Celular/genética , Desenvolvimento Embrionário , Animais , Caenorhabditis elegans/embriologia , Caenorhabditis elegans/genética , Linhagem da Célula/genética , Movimento Celular , Regulação da Expressão Gênica no Desenvolvimento
7.
Nucleic Acids Res ; 42(Web Server issue): W130-6, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24875471

RESUMO

Interactions among transcriptional factors (TFs), cofactors and other proteins or enzymes can affect transcriptional regulatory capabilities of eukaryotic organisms. Post-translational modifications (PTMs) cooperate with TFs and epigenetic alterations to constitute a hierarchical complexity in transcriptional gene regulation. While clearly implicated in biological processes, our understanding of these complex regulatory mechanisms is still limited and incomplete. Various online software have been proposed for uncovering transcriptional and epigenetic regulatory networks, however, there is a lack of effective web-based software capable of constructing underlying interactive organizations between post-translational and transcriptional regulatory components. Here, we present an open web server, post-translational hierarchical gene regulatory network (PTHGRN) to unravel relationships among PTMs, TFs, epigenetic modifications and gene expression. PTHGRN utilizes a graphical Gaussian model with partial least squares regression-based methodology, and is able to integrate protein-protein interactions, ChIP-seq and gene expression data and to capture essential regulation features behind high-throughput data. The server provides an integrative platform for users to analyze ready-to-use public high-throughput Omics resources or upload their own data for systems biology study. Users can choose various parameters in the method, build network topologies of interests and dissect their associations with biological functions. Application of the software to stem cell and breast cancer demonstrates that it is an effective tool for understanding regulatory mechanisms in biological complex systems. PTHGRN web server is publically available at web site http://www.byanbioinfo.org/pthgrn.


Assuntos
Imunoprecipitação da Cromatina , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Mapeamento de Interação de Proteínas , Software , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Diferenciação Celular/genética , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Internet , Células MCF-7 , Camundongos , Processamento de Proteína Pós-Traducional , Ratos , Fatores de Transcrição/metabolismo
8.
Bioinformatics ; 30(8): 1190-1192, 2014 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-24389658

RESUMO

ChIP-seq technology provides an accurate characterization of transcription or epigenetic factors binding on genomic sequences. With integration of such ChIP-based and other high-throughput information, it would be dedicated to dissecting cross-interactions among multilevel regulators, genes and biological functions. Here, we devised an integrative web server CMGRN (constructing multilevel gene regulatory networks), to unravel hierarchical interactive networks at different regulatory levels. The newly developed method used the Bayesian network modeling to infer causal interrelationships among transcription factors or epigenetic modifications by using ChIP-seq data. Moreover, it used Bayesian hierarchical model with Gibbs sampling to incorporate binding signals of these regulators and gene expression profile together for reconstructing gene regulatory networks. The example applications indicate that CMGRN provides an effective web-based framework that is able to integrate heterogeneous high-throughput data and to reveal hierarchical 'regulome' and the associated gene expression programs. AVAILABILITY: http://bioinfo.icts.hkbu.edu.hk/cmgrn; http://www.byanbioinfo.org/cmgrn CONTACT: yanbinai6017@gmail.com or junwen@hku.hk Supplementary Information: Supplementary data are available at Bioinformatics online.


Assuntos
Biologia Computacional/métodos , Redes de Comunicação de Computadores , Redes Reguladoras de Genes , Genômica/métodos , Teorema de Bayes , Imunoprecipitação da Cromatina , Epigênese Genética , Expressão Gênica , Internet , Análise de Sequência com Séries de Oligonucleotídeos , Software , Fatores de Transcrição/metabolismo
9.
J Exp Bot ; 66(5): 1477-88, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25547914

RESUMO

Cassava is one of the most drought-tolerant crops, however, the underlying mechanism for its ability to survive and produce under drought remains obscure. In this study, two cassava cultivars, SC124 and Arg7, were treated by gradually reducing the soil water content. Their responses to the drought stress were examined through their morphological and physiological traits and isobaric tags for relative and absolute quantitation (iTRAQ)-based proteomic analysis. SC124 plants adapted a 'survival' mode under mild drought stress as evidenced by early stomatal closure and a reduction in the levels of various photosynthetic proteins and photosynthetic capacity, resulting in early growth quiescence. In contrast, Arg7 plants underwent senescence of older leaves but continued to grow, although at a reduced rate, under mild drought. SC124 plants were more capable of surviving prolonged severe drought than Arg7. The iTRAQ analysis identified over 5000 cassava proteins. Among the drought-responsive proteins identified in the study were an aquaporin, myo-inositol 1-phosphate synthases, and a number of proteins involved in the antioxidant systems and secondary metabolism. Many proteins that might play a role in signalling or gene regulation were also identified as drought-responsive proteins, which included several protein kinases, two 14-3-3 proteins, several RNA-binding proteins and transcription factors, and two histone deacetylases. Our study also supports the notion that linamarin might play a role in nitrogen reallocation in cassava under drought.


Assuntos
Manihot/crescimento & desenvolvimento , Manihot/fisiologia , Secas , Regulação da Expressão Gênica de Plantas , Manihot/classificação , Manihot/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteômica , Estresse Fisiológico , Água/metabolismo
10.
Zhonghua Zhong Liu Za Zhi ; 37(10): 759-63, 2015 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-26813595

RESUMO

OBJECTIVE: To identify SNPs in the miRNA genes in colorectal cancer (CRC) patients and to investigate their association with CRC. METHODS: DNAs were isolated from 30 CRC tumor tissues and 30 tumor-adjacent tissues, and subjected to target capture using a custom miRNA chip covering 685 miRNA genes from NimbleGen. The captured DNAs were then sequenced using the Illumina's sequencing technology, and the data were analyzed. RESULTS: We identified 64 SNPs in 43 miRNA genes and most of these SNPs are novel SNPs not reported previously. Prediction of functional consequences of the SNPs using TargetScan and miRSNP showed that SNPs of hsa-mir-1273-G/A, hsa-mir-548h-3-C/U, hsa-mir-1290-A/G, and hsa-mir-1273-C/U resulted in reduction of their mature miRNA abundance. SNPs of hsa-mir-376b-C/G, hsa-mir-604-T/C, hsa-mir-1268-T/G and hsa-mir-146a-C/G resulted in changes in their targeted genes. Finally, we focused on the analysis of SNPs in mir-146a and we found that mir-146a rs1052918 C>G was predicted to promote tumorigenesis via the Wnt signaling pathway. CONCLUSIONS: SNPs in the miRNA genes are important for tumorigenesis. The changes by hsa-mir-146a rs1052918 C>G may result in loss of Wnt, constant activation of the Wnt signaling pathway, and uncontrolled cell proliferation and tumor progression.


Assuntos
Neoplasias Colorretais/genética , MicroRNAs/fisiologia , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , Sequência de Bases , Proliferação de Células , Neoplasias Colorretais/patologia , Humanos , Análise de Sequência com Séries de Oligonucleotídeos
11.
J Biol Chem ; 288(46): 33411-26, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24097988

RESUMO

Cell fate specification is typically initiated by a master regulator, which is relayed by tissue-specific regulatory proteins (usually transcription factors) for further enforcement of cell identities, but how the factors are coordinated among each other to "finish up" the specification remains poorly understood. Caenorhabditis elegans epidermis specification is initiated by a master regulator, ELT-1, that activates its targets, NHR-25 and ELT-3, two epidermis-specific transcription factors that are important for development but not for initial specification of epidermis, thus providing a unique paradigm for illustrating how the tissue-specific regulatory proteins work together to enforce cell fate specification. Here we addressed the question through contrasting genome-wide in vivo binding targets between NHR-25 and ELT-3. We demonstrate that the two factors bind discrete but conserved DNA motifs, most of which remain in proximity, suggesting formation of a complex between the two. In agreement with this, gene ontology analysis of putative target genes suggested differential regulation of metabolism but coordinated control of epidermal development between the two factors, which is supported by quantitative analysis of expression of their specific or common targets in the presence or absence of either protein. Functional validation of a subset of the target genes showed both activating and inhibitory roles of NHR-25 and ELT-3 in regulating their targets. We further demonstrated differential control of specification of AB and C lineage-derived epidermis. The results allow us to assemble a comprehensive gene network underlying C. elegans epidermis development that is likely to be widely used across species and provides insights into how tissue-specific transcription factors coordinate with one another to enforce cell fate specification initiated by its master regulator.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Proteínas de Ligação a DNA/metabolismo , Epiderme/metabolismo , Fatores de Transcrição GATA/metabolismo , Fatores de Transcrição/metabolismo , Animais , Caenorhabditis elegans/citologia , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Proteínas de Ligação a DNA/genética , Células Epidérmicas , Fatores de Transcrição GATA/genética , Estudo de Associação Genômica Ampla , Especificidade de Órgãos/fisiologia , Fatores de Transcrição/genética
12.
Genet Res (Camb) ; 96: e005, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25023089

RESUMO

The fundamental step of learning transcriptional regulation mechanism is to identify the target genes regulated by transcription factors (TFs). Despite numerous target genes identified by chromatin immunoprecipitation followed by high-throughput sequencing technology (ChIP-seq) assays, it is not possible to infer function from binding alone in vivo. This is equally true in one of the best model systems, the nematode Caenorhabditis elegans (C. elegans), where regulation often occurs through diverse TF binding features of transcriptional networks identified in modENCODE. Here, we integrated ten ChIP-seq datasets with genome-wide expression data derived from tiling arrays, involved in six TFs (HLH-1, ELT-3, PQM-1, SKN-1, CEH-14 and LIN-11) with tissue-specific and four TFs (CEH-30, LIN-13, LIN-15B and MEP-1) with broad expression patterns. In common, TF bindings within 3 kb upstream of or within its target gene for these ten studies showed significantly elevated level of expression as opposed to that of non-target controls, indicated that these sites may be more likely to be functional through up-regulating its target genes. Intriguingly, expression of the target genes out of 5 kb upstream of their transcription start site also showed high levels, which was consistent with the results of following network component analysis. Our study has identified similar transcriptional regulation mechanisms of tissue-specific or broad expression TFs in C. elegans using ChIP-seq and gene expression data. It may also provide a novel insight into the mechanism of transcriptional regulation not only for simple organisms but also for more complex species.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/genética , Imunoprecipitação da Cromatina/métodos , Perfilação da Expressão Gênica/métodos , Redes Reguladoras de Genes , Fatores de Transcrição/metabolismo , Animais , Sítios de Ligação , Proteínas de Caenorhabditis elegans/metabolismo , Regulação da Expressão Gênica , Análise de Sequência com Séries de Oligonucleotídeos , Ligação Proteica
13.
BMC Neurol ; 14: 207, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25366337

RESUMO

BACKGROUND: SOX4 is a transcription factor required for tissue development and differentiation in vertebrates. Overexpression of SOX4 has been reported in many cancers including glioblastoma multiforme (GBM), however, the underlying mechanism of actions has not been studied. In this study, we investigated the role of SOX4 in GBM. METHODS: Kaplan-Meier analysis was performed to assess the association between SOX4 expression levels and survival times in primary GBM samples. Cre/lox P system was used to generate gain or loss of SOX4 in GBM cells, and microarray analysis uncovered the regulation network of SOX4 in GBM cells. RESULTS: High SOX4 expression was significantly associated with good prognosis of primary GBMs. SOX4 inhibited the growth of GBM cell line LN229, A172G and U87MG, partly via the activation of p53-p21 signaling and down-regulation of phosphorylated AKT1. Gene expression profiling and subsequent gene ontology analysis showed that SOX4 influenced several key pathways including the Wnt/ beta-catenin and TGF-beta signaling pathways. CONCLUSIONS: Our study found that SOX4 acts as a tumor suppressor in GBM cells by induce cell cycle arrest and inhibiting cell growth.


Assuntos
Glioblastoma/patologia , Fatores de Transcrição SOXC/genética , Linhagem Celular Tumoral , Proliferação de Células , Regulação para Baixo , Pontos de Checagem da Fase G1 do Ciclo Celular/fisiologia , Glioblastoma/genética , Humanos , Estimativa de Kaplan-Meier , Transdução de Sinais
14.
BMC Genomics ; 14: 851, 2013 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-24304681

RESUMO

BACKGROUND: Cavendish, the most widely grown banana cultivar, is relatively resistant to Race 1 of Fusarium oxysporum f. sp. cubense (Foc1) which caused widespread Panama disease during the first half of the 20th century but is susceptible to Tropical Race 4 of Foc (Foc TR4) which is threatening world banana production. The genome of the diploid species Musa acuminata which is the ancestor of a majority of triploid banana cultivars has recently been sequenced. Availability of banana transcriptomes will be highly useful for improving banana genome annotation and for biological research. The knowledge of global gene expression patterns influenced by infection of different Foc races will help to understand the host responses to the infection. RESULTS: RNA samples from different organs of the Cavendish cultivar were pooled for deep sequencing using the Illumina technology. Analysis of the banana transcriptome led to identification of over 842 genes that were not annotated by the Musa genome project. A large number of simple nucleotide polymorphisms (SNPs) and short insertions and deletion (indels) were identified from the transcriptome data. GFP-expressing Foc1 and Foc TR4 were used to monitor the infection process. Both Foc1 and Foc TR4 were found to be able to invade banana roots and spread to root vascular tissues in the first two days following inoculation. Digital gene expression (DGE) profiling analysis reveal that the infection by Foc1 and Foc TR4 caused very similar changes in the global gene expression profiles in the banana roots during the first two days of infection. The Foc infection led to induction of many well-known defense-related genes. Two genes encoding the ethylene biosynthetic enzyme ACC oxidase and several ethylene-responsive transcription factors (ERF) were among the strongly induced genes by both Foc1 and Foc TR4. CONCLUSIONS: Both Foc1 and Foc TR4 are able to spread into the vascular system of banana roots during the early infection process and their infection led to similar gene expression profiles in banana roots. The transcriptome profiling analysis indicates that the ethylene synthetic and signalling pathways were activated in response to the Foc infection.


Assuntos
Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Musa/genética , Doenças das Plantas/genética , Raízes de Plantas/genética , Transcriptoma , Análise por Conglomerados , Etiquetas de Sequências Expressas , Fusarium , Expressão Gênica , Genes Reporter , Mutação INDEL , Dados de Sequência Molecular , Musa/microbiologia , Doenças das Plantas/microbiologia , Raízes de Plantas/microbiologia , Polimorfismo de Nucleotídeo Único
15.
Geriatr Gerontol Int ; 22(8): 635-641, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35789056

RESUMO

AIM: Nonagenarians with community-acquired pneumonia (CAP) have a high mortality rate; however, appropriate tools for reliable severity assessment in this population are lacking. The current study aimed to evaluate the risk factors and establish a nomogram to predict in-hospital mortality of nonagenarians with CAP. METHODS: In total, 304 patients aged ≥90 years who were admitted with CAP to Jiangsu Provincial People's Hospital and Jiangsu Provincial Hospital of Chinese Medicine between 2014 and 2020 were retrospectively analyzed. Clinical information, laboratory imaging results and pathogen detection were retrieved. Significant variables independently associated with CAP were identified by a logistic regression model, and a nomogram prediction model was constructed. The nomogram was compared with the widely used assessments: CURB-65, PSI and National Early Warning Score (NEWS) scores. RESULTS: Univariate and multivariate logistic regression analyses identified gender, blood urea nitrogen, C-reactive protein-to-albumin ratio, Charlson Comorbidity Index and systemic immune inflammation index as independent factors that affect the prognosis. We created a nomogram for CAP based on these risk factors. The nomogram had a bootstrapped concordance index of 0.796 and was well-calibrated in the decision analysis curve range of 0.1-0.98. The area under the curve was 0.796 (95% CI: 0.74-0.85), significantly higher than for CURB-65, PSI and NEWS scores (P < 0.05). CONCLUSIONS: Our nomogram model can predict the outcome of hospitalized nonagenarians with CAP and guide clinicians to provide better treatment, leading to improved prognosis and reduced mortality. Geriatr Gerontol Int 2022; 22: 635-641.


Assuntos
Infecções Comunitárias Adquiridas , Pneumonia , Idoso de 80 Anos ou mais , Infecções Comunitárias Adquiridas/diagnóstico , Mortalidade Hospitalar , Humanos , Nomogramas , Nonagenários , Pneumonia/diagnóstico , Prognóstico , Estudos Retrospectivos , Índice de Gravidade de Doença
16.
Cell Rep ; 41(5): 111576, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36323253

RESUMO

The nuclear pore complex (NPC) comprises more than 30 nucleoporins (NUPs) and is a hallmark of eukaryotes. NUPs have been suggested to be important in regulating gene transcription and 3D genome organization. However, evidence in support of their direct roles remains limited. Here, by Cut&Run, we find that core NUPs display broad but also cell-type-specific association with active promoters and enhancers in human cells. Auxin-mediated rapid depletion of two NUPs demonstrates that NUP93, but not NUP35, directly and specifically controls gene transcription. NUP93 directly activates genes with high levels of RNA polymerase II loading and transcriptional elongation by facilitating full BRD4 recruitment to their active enhancers. dCas9-based tethering confirms a direct and causal role of NUP93 in gene transcriptional activation. Unexpectedly, in situ Hi-C and H3K27ac or H3K4me1 HiChIP results upon acute NUP93 depletion show negligible changesS2211-1247(22)01437-1 of 3D genome organization ranging from A/B compartments and topologically associating domains (TADs) to enhancer-promoter contacts.


Assuntos
Complexo de Proteínas Formadoras de Poros Nucleares , Proteínas Nucleares , Humanos , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Proteínas Nucleares/genética , Fatores de Transcrição/genética , Poro Nuclear , Genoma , Cromatina , Proteínas de Ciclo Celular/genética
17.
Endocrine ; 75(1): 1-9, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34716852

RESUMO

Type 2 diabetes (T2D) increases the risk of coronavirus disease (COVID-19). This study investigates the association between glucose control of COVID-19 patients with T2D in first 7 days after hospital admission and prognosis. A total of 252 infected inpatients with T2D in China were included. Well-controlled blood glucose was defined as stable fasting blood glucose (FBG) levels in the range of 3.9-7.8 mmol/L during first 7 days using indicators of average (FBGA), maximum (FBGM) or first-time (FBG1) FBG levels. The primary endpoint was admission to intensive care unit or death. Hazard ratio (HR) of poorly controlled glucose level group compared with well-controlled group were 4.96 (P = 0.021) for FBGM and 5.55 (P = 0.014) for FBGA. Well-controlled blood glucose levels in first 7 days could improve the prognosis of COVID-19 inpatients with diabetes.


Assuntos
COVID-19 , Diabetes Mellitus Tipo 2 , Glicemia , Diabetes Mellitus Tipo 2/complicações , Humanos , Pacientes Internados , Prognóstico , Estudos Retrospectivos , Fatores de Risco , SARS-CoV-2
18.
BMC Genomics ; 12: 11, 2011 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-21211035

RESUMO

BACKGROUND: SOX2 is a key gene implicated in maintaining the stemness of embryonic and adult stem cells. SOX2 appears to re-activate in several human cancers including glioblastoma multiforme (GBM), however, the detailed response program of SOX2 in GBM has not yet been defined. RESULTS: We show that knockdown of the SOX2 gene in LN229 GBM cells reduces cell proliferation and colony formation. We then comprehensively characterize the SOX2 response program by an integrated analysis using several advanced genomic technologies including ChIP-seq, microarray profiling, and microRNA sequencing. Using ChIP-seq technology, we identified 4883 SOX2 binding regions in the GBM cancer genome. SOX2 binding regions contain the consensus sequence wwTGnwTw that occurred 3931 instances in 2312 SOX2 binding regions. Microarray analysis identified 489 genes whose expression altered in response to SOX2 knockdown. Interesting findings include that SOX2 regulates the expression of SOX family proteins SOX1 and SOX18, and that SOX2 down regulates BEX1 (brain expressed X-linked 1) and BEX2 (brain expressed X-linked 2), two genes with tumor suppressor activity in GBM. Using next generation sequencing, we identified 105 precursor microRNAs (corresponding to 95 mature miRNAs) regulated by SOX2, including down regulation of miR-143, -145, -253-5p and miR-452. We also show that miR-145 and SOX2 form a double negative feedback loop in GBM cells, potentially creating a bistable system in GBM cells. CONCLUSIONS: We present an integrated dataset of ChIP-seq, expression microarrays and microRNA sequencing representing the SOX2 response program in LN229 GBM cells. The insights gained from our integrated analysis further our understanding of the potential actions of SOX2 in carcinogenesis and serves as a useful resource for the research community.


Assuntos
Glioblastoma/genética , MicroRNAs/genética , Fatores de Transcrição SOXB1/metabolismo , Imunoprecipitação da Cromatina , Humanos , MicroRNAs/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Análise de Sequência de DNA
19.
Hepatol Int ; 15(1): 202-212, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33548030

RESUMO

BACKGROUND: Infection with SARS-CoV-2 has been associated with liver dysfunction, aggravation of liver burden, and liver injury. This study aimed to assess the effects of liver injuries on the clinical outcomes of patients with COVID-19. METHODS: A total of 1520 patients with severe or critical COVID-19 from Huoshenshan Hospital, Wuhan, were enrolled. Chronic liver disease (CLD) was confirmed by consensus diagnostic criteria. Laboratory test results were compared between different groups. scRNA-seq data and bulk gene expression profiles were used to identify cell types associated with liver injury. RESULTS: A total of 10.98% of patients with severe or critical COVID-19 developed liver injury after admission that was associated with significantly higher rates of mortality (21.74%, p < 0.001) and intensive care unit admission (26.71%, p < 0.001). Pre-existing CLDs were not associated with a higher risk. However, fatty liver disease and cirrhosis were associated with higher risks, supported by evidences from single cell and bulk transcriptome analysis that showed more TMPRSS2+ cells in these tissues. By generating a model, we were able to predict the risk and severity of liver injury during hospitalization. CONCLUSION: We demonstrate that liver injury occurring during therapy as well as pre-existing CLDs like fatty liver disease and cirrhosis in patients with COVID-19 is significantly associated with the severity of disease and mortality, but the presence of other CLD is not associated. We provide a risk-score model that can predict whether patients with COVID-19 will develop liver injury or proceed to higher-risk stages during subsequent hospitalizations.


Assuntos
COVID-19/complicações , COVID-19/terapia , Hepatopatias/diagnóstico , Hepatopatias/virologia , Adulto , Idoso , COVID-19/mortalidade , China , Cuidados Críticos , Oxigenação por Membrana Extracorpórea , Feminino , Hospitalização , Humanos , Hepatopatias/mortalidade , Masculino , Pessoa de Meia-Idade , Oxigenoterapia , Respiração Artificial , Fatores de Risco , Índice de Gravidade de Doença , Taxa de Sobrevida
20.
Appl Microbiol Biotechnol ; 85(4): 1105-14, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19820924

RESUMO

Using a deep serial analysis of gene expression (DeepSAGE) sequencing approach, we profiled the transcriptional response of Fusarium graminearum to tebuconazole, a most widely used azole fungicide. By comparing the expression of genes in F. graminearum treated and untreated with tebuconazole, we identified 324 and 155 genes showing more than a 5-fold increase and decrease, respectively, in expression upon tebuconazole treatment. These genes are involved in a variety of cell functions including egrosterol biosynthesis, transcription, and cellular metabolism. The validity of DeepSAGE results were confirmed by real-time PCR analysis of expression of 20 genes with different expression levels in the DeepSAGE analysis. The results from this study provide useful information in understanding the mechanisms for the responses of F. graminearum to azole fungicides.


Assuntos
Fungicidas Industriais/farmacologia , Fusarium/efeitos dos fármacos , Fusarium/genética , Perfilação da Expressão Gênica , Triazóis/farmacologia , Fusarium/metabolismo , Expressão Gênica/efeitos dos fármacos , Perfilação da Expressão Gênica/métodos , Genes Fúngicos , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Biossíntese de Peptídeos Independentes de Ácido Nucleico/genética , Reação em Cadeia da Polimerase , Proteoma/genética , Proteoma/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Esteróis/metabolismo
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa