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1.
Neurobiol Dis ; 119: 149-158, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30099093

RESUMO

BACKGROUND: With the capacity to modulate gene networks in an environmentally-sensitive manner, the role of epigenetic systems in mental disorders has come under intense investigation. Dysregulation of epigenetic effectors, including microRNAs and histone-modifying enzymes, may better explain the role of environmental risk factors and the observed heritability rate that cannot be fully attributed to known genetic risk alleles. Here, we aimed to identify novel epigenetic targets of the schizophrenia-associated microRNA 132 (miR-132). METHODS: Histone modifications were quantified by immunodetection in response to viral-mediated overexpression of miR-132 while a luminescent reporter system was used to validate targets of miR-132 in vitro. Genome-wide profiling, quantitative PCR and NanoSting were used to quantify gene expression in post-mortem human brains, neuronal cultures and prefrontal cortex (PFC) of mice chronically exposed to antipsychotics. Following viral-mediated depletion of Enhancer of Zeste 1 (EZH1) in the murine PFC, behaviors including sociability and motivation were assessed using a 3-chambered apparatus and forced-swim test, respectively. RESULTS: Overexpression of miR-132 decreased global histone 3 lysine 27 tri-methylation (H3K27me3), a repressive epigenetic mark. Moreover, the polycomb-associated H3K27 methyltransferase, EZH1, is regulated by miR-132 and upregulated in the PFC of schizophrenics. Unlike its homolog EZH2, expression of EZH1 in the murine PFC decreased following chronic exposure to antipsychotics. Viral-mediated depletion of EZH1 in the mouse PFC attenuated sociability, enhanced motivational behaviors, and affected gene expression pathways related to neurotransmission and behavioral phenotypes. CONCLUSIONS: EZH1 is dysregulated in schizophrenia, sensitive to antipsychotic medications, and a brain-enriched miR-132 target that controls neurobehavioral phenotypes.


Assuntos
Antipsicóticos/uso terapêutico , Epigênese Genética/fisiologia , Motivação/fisiologia , Complexo Repressor Polycomb 2/biossíntese , Esquizofrenia/metabolismo , Comportamento Social , Adulto , Idoso , Animais , Antipsicóticos/farmacologia , Linhagem Celular Tumoral , Estudos de Coortes , Epigênese Genética/efeitos dos fármacos , Feminino , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Motivação/efeitos dos fármacos , Complexo Repressor Polycomb 2/genética , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Esquizofrenia/tratamento farmacológico , Esquizofrenia/genética
2.
Mol Cell Neurosci ; 85: 183-189, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29055697

RESUMO

Natural antisense transcripts (NATs) are an abundant class of long noncoding RNAs that have recently been shown to be key regulators of chromatin dynamics and gene expression in nervous system development and neurological disorders. However, it is currently unclear if NAT-based mechanisms also play a role in drug-induced neuroadaptations. Aberrant regulation of gene expression is one critical factor underlying the long-lasting behavioral abnormalities that characterize substance use disorder, and it is possible that some drug-induced transcriptional responses are mediated, in part, by perturbations in NAT activity. To test this hypothesis, we used an automated algorithm that mines the NCBI AceView transcriptomics database to identify NAT overlapping genes linked to addiction. We found that 22% of the genes examined contain NATs and that expression of Homer1 natural antisense transcript (Homer1-AS) was altered in the nucleus accumbens (NAc) of mice 2h and 10days following repeated cocaine administration. In in vitro studies, depletion of Homer1-AS lead to an increase in the corresponding sense gene expression, indicating a potential regulatory mechanisms of Homer1 expression by its corresponding antisense transcript. Future in vivo studies are needed to definitely determine a role for Homer1-AS in cocaine-induced behavioral and molecular adaptations.


Assuntos
Cocaína/farmacologia , Inibidores da Captação de Dopamina/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas de Arcabouço Homer/efeitos dos fármacos , Núcleo Accumbens/efeitos dos fármacos , RNA Antissenso/biossíntese , Animais , Regulação da Expressão Gênica/genética , Proteínas de Arcabouço Homer/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , RNA Antissenso/efeitos dos fármacos
3.
Mol Cell Neurosci ; 74: 49-57, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27001315

RESUMO

Triplet repeat expansions in the Fragile X mental retardation 1 (FMR1) gene cause either intellectual disability and autism, or adult-onset neurodegeneration, with poorly understood variability in presentation. Previous studies have identified several long noncoding RNAs (lncRNAs) at the FMR1 locus, including FMR4. Similarly to FMR1, FMR4 is silenced by large-repeat expansions that result in enrichment of DNA and histone methylation within the shared promoter and repeat sequence, suggesting a possible role for this noncoding RNA in the pathophysiology of Fragile X. We therefore assessed the functional role of FMR4 to gain further insight into the molecular processes in Fragile X-associated disorders. Previous work showed that FMR4 does not exhibit cis-regulation of FMR1. Here, we found that FMR4 is a chromatin-associated transcript and, using genome-wide chromatin immunoprecipitation experiments, showed that FMR4 alters the chromatin state and the expression of several hundred genes in trans. Among the genes regulated by FMR4, we found enrichment for those involved in neural development and cellular proliferation. S-phase marker assays further demonstrated that FMR4 may promote cellular proliferation, rather than differentiation, of human neural precursor cells (hNPCs). By establishing this novel function for FMR4 in hNPCs, we lend support to existing evidence of the epigenetic involvement of lncRNA in nervous system development, and increase our understanding of the complex pathogenesis underlying neurological disorders associated with FMR1 repeat expansions.


Assuntos
Proliferação de Células , Células-Tronco Embrionárias/metabolismo , Epigênese Genética , Regulação da Expressão Gênica no Desenvolvimento , Células-Tronco Neurais/metabolismo , RNA Longo não Codificante/genética , Células Cultivadas , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/fisiologia , Genes Controladores do Desenvolvimento , Células HEK293 , Humanos , Células-Tronco Neurais/citologia , Células-Tronco Neurais/fisiologia , Neurogênese , RNA Longo não Codificante/metabolismo
4.
BMC Genomics ; 17: 49, 2016 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-26758513

RESUMO

BACKGROUND: Next generation sequencing (NGS) technologies are indispensable for molecular biology research, but data analysis represents the bottleneck in their application. Users need to be familiar with computer terminal commands, the Linux environment, and various software tools and scripts. Analysis workflows have to be optimized and experimentally validated to extract biologically meaningful data. Moreover, as larger datasets are being generated, their analysis requires use of high-performance servers. RESULTS: To address these needs, we developed CANEapp (application for Comprehensive automated Analysis of Next-generation sequencing Experiments), a unique suite that combines a Graphical User Interface (GUI) and an automated server-side analysis pipeline that is platform-independent, making it suitable for any server architecture. The GUI runs on a PC or Mac and seamlessly connects to the server to provide full GUI control of RNA-sequencing (RNA-seq) project analysis. The server-side analysis pipeline contains a framework that is implemented on a Linux server through completely automated installation of software components and reference files. Analysis with CANEapp is also fully automated and performs differential gene expression analysis and novel noncoding RNA discovery through alternative workflows (Cuffdiff and R packages edgeR and DESeq2). We compared CANEapp to other similar tools, and it significantly improves on previous developments. We experimentally validated CANEapp's performance by applying it to data derived from different experimental paradigms and confirming the results with quantitative real-time PCR (qRT-PCR). CANEapp adapts to any server architecture by effectively using available resources and thus handles large amounts of data efficiently. CANEapp performance has been experimentally validated on various biological datasets. CANEapp is available free of charge at http://psychiatry.med.miami.edu/research/laboratory-of-translational-rna-genomics/CANE-app . CONCLUSIONS: We believe that CANEapp will serve both biologists with no computational experience and bioinformaticians as a simple, timesaving but accurate and powerful tool to analyze large RNA-seq datasets and will provide foundations for future development of integrated and automated high-throughput genomics data analysis tools. Due to its inherently standardized pipeline and combination of automated analysis and platform-independence, CANEapp is an ideal for large-scale collaborative RNA-seq projects between different institutions and research groups.


Assuntos
Perfilação da Expressão Gênica/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , RNA/genética , Software , Genômica , Internet , Interface Usuário-Computador
5.
Eur J Neurosci ; 44(10): 2858-2870, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27564458

RESUMO

Astrocytes are a morphologically and functionally heterogeneous population of cells that play critical roles in neurodevelopment and in the regulation of central nervous system homeostasis. Studies of human astrocytes have been hampered by the lack of specific molecular markers and by the difficulties associated with purifying and culturing astrocytes from adult human brains. Human neural progenitor cells (NPCs) with self-renewal and multipotent properties represent an appealing model system to gain insight into the developmental genetics and function of human astrocytes, but a comprehensive molecular characterization that confirms the validity of this cellular system is still missing. Here we used an unbiased transcriptomic analysis to characterize in vitro culture of human NPCs and to define the gene expression programs activated during the differentiation of these cells into astrocytes using FBS or the combination of CNTF and BMP4. Our results demonstrate that in vitro cultures of human NPCs isolated during the gliogenic phase of neurodevelopment mainly consist of radial glial cells (RGCs) and glia-restricted progenitor cells. In these cells the combination of CNTF and BMP4 activates the JAK/STAT and SMAD signaling cascades, leading to the inhibition of oligodendrocytes lineage commitment and activation of astrocytes differentiation. On the other hand, FBS-derived astrocytes have properties of reactive astrocytes. Our work suggests that in vitro culture of human NPCs represents a valuable cellular system to study human disorders characterized by impairment of astrocytes development and function. Our datasets represent an important resource for researchers studying human astrocytes development and might set the basis for the discovery of novel human-specific astrocyte markers.


Assuntos
Astrócitos/metabolismo , Células-Tronco Embrionárias/metabolismo , Células-Tronco Neurais/metabolismo , Transcriptoma , Astrócitos/citologia , Proteína Morfogenética Óssea 4/genética , Proteína Morfogenética Óssea 4/metabolismo , Células Cultivadas , Fator Neurotrófico Ciliar/genética , Fator Neurotrófico Ciliar/metabolismo , Células-Tronco Embrionárias/citologia , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Janus Quinases/genética , Janus Quinases/metabolismo , Células-Tronco Neurais/citologia , Neurogênese , Fatores de Transcrição STAT/genética , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais , Proteínas Smad/genética , Proteínas Smad/metabolismo
6.
Trends Genet ; 28(8): 389-96, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22541732

RESUMO

In the decade following the publication of the Human Genome, noncoding RNAs (ncRNAs) have reshaped our understanding of the broad landscape of genome regulation. During this period, natural antisense transcripts (NATs), which are transcribed from the opposite strand of either protein or non-protein coding genes, have vaulted to prominence. Recent findings have shown that NATs can exert their regulatory functions by acting as epigenetic regulators of gene expression and chromatin remodeling. Here, we review recent work on the mechanisms of epigenetic modifications by NATs and their emerging role as master regulators of chromatin states. Unlike other long ncRNAs, antisense RNAs usually regulate their counterpart sense mRNA in cis by bridging epigenetic effectors and regulatory complexes at specific genomic loci. Understanding the broad range of effects of NATs will shed light on the complex mechanisms that regulate chromatin remodeling and gene expression in development and disease.


Assuntos
Cromatina/genética , RNA Antissenso/genética , RNA não Traduzido/genética , Transcrição Gênica , Animais , Epigênese Genética , Humanos
7.
J Vasc Res ; 52(2): 71-80, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26088024

RESUMO

Adenosine and uridine triphosphate (ATP and UTP) can act as extracellular signalling molecules, playing important roles in vascular biology and disease. ATP and UTP acting via the P2Y2-receptor have, for example, been shown to regulate endothelial dilatation, inflammation and angiogenesis. MicroRNAs (miRNAs), a class of regulatory, short, non-coding RNAs, have been shown to be important regulators of these biological processes. In this study, we used RNA deep-sequencing to explore changes in miRNA expression in the human microvascular endothelial cell line HMEC-1 upon UTP treatment. The expression of miR-22, which we have previously shown to target ICAM-1 mRNA in HMEC-1, increased significantly after stimulation. Up-regulation of miR-22 and down-regulation of cell surface ICAM-1 were confirmed with qRT-PCR and flow cytometry, respectively. siRNA-mediated knockdown of the P2Y2-receptor abolished the effect of UTP on miR-22 transcription. Leukocyte adhesion was significantly inhibited in HMEC-1 following miR-22 overexpression and treatment with UTP/ATP. In conclusion, extracellular UTP and ATP can attenuate ICAM-1 expression and leukocyte adhesion in endothelial cells through miR-22.


Assuntos
Trifosfato de Adenosina/farmacologia , Anti-Inflamatórios/farmacologia , Células Endoteliais/efeitos dos fármacos , Inflamação/prevenção & controle , Molécula 1 de Adesão Intercelular/metabolismo , MicroRNAs/metabolismo , Agonistas do Receptor Purinérgico P2Y/farmacologia , Uridina Trifosfato/farmacologia , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Técnicas de Cocultura , Relação Dose-Resposta a Droga , Células Endoteliais/imunologia , Células Endoteliais/metabolismo , Citometria de Fluxo , Regulação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Inflamação/genética , Inflamação/imunologia , Inflamação/metabolismo , Molécula 1 de Adesão Intercelular/imunologia , Leucócitos/efeitos dos fármacos , Leucócitos/imunologia , Leucócitos/metabolismo , MicroRNAs/genética , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas , Interferência de RNA , Receptores Purinérgicos P2Y2/efeitos dos fármacos , Receptores Purinérgicos P2Y2/genética , Receptores Purinérgicos P2Y2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Transfecção
8.
EMBO J ; 28(12): 1708-19, 2009 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-19461583

RESUMO

Small interfering RNAs (siRNAs) directed to gene promoters can silence genes at the transcriptional level. siRNA-directed transcriptional silencing (RdTS) was first described in plants and yeasts and more recently in mammalian cells. RdTS has been associated with the induction of epigenetic changes and the formation of complexes containing RNA interference and chromatin-remodelling factors. Here, we show that a promoter-targeted siRNA inhibits transcription of the c-myc gene. Transcriptional silencing of c-myc did not involve changes of known epigenetic marks. Instead, the c-myc promoter-targeted siRNA interfered with transcription initiation blocking the assembly of the pre-initiation complex. Transcriptional interference depended on Argonaute 2 and a noncoding promoter-associated RNA initiated upstream and overlapping the transcription start site. Silencing of c-myc led to growth arrest, reduced clonogenic potential and senescence of c-myc over-expressing prostate cancer cells with minimal effect on normal cells. RNA-directed transcriptional interference may be a natural mechanism of transcriptional control and siRNAs targeting noncoding RNAs participating in this regulatory pathway could be valuable tools to control expression of deregulated genes in human diseases.


Assuntos
Regiões Promotoras Genéticas/genética , Proteínas Proto-Oncogênicas c-myc/genética , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Transcrição Gênica , Proteínas Argonautas , Linhagem Celular Tumoral , Proliferação de Células , Senescência Celular , Fator de Iniciação 2 em Eucariotos/metabolismo , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Neoplásico/metabolismo , RNA não Traduzido/genética , Ensaio Tumoral de Célula-Tronco
10.
Cancer Res Commun ; 1(1): 1-16, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-35528192

RESUMO

A comprehensive constellation of somatic non-silent mutations and copy number (CN) variations in ocular adnexa marginal zone lymphoma (OAMZL) is unknown. By utilizing whole-exome sequencing in 69 tumors we define the genetic landscape of OAMZL. Mutations and CN changes in CABIN1 (30%), RHOA (26%), TBL1XR1 (22%), and CREBBP (17%) and inactivation of TNFAIP3 (26%) were among the most common aberrations. Candidate cancer driver genes cluster in the B-cell receptor (BCR), NFkB, NOTCH and NFAT signaling pathways. One of the most commonly altered genes is CABIN1, a calcineurin inhibitor acting as a negative regulator of the NFAT and MEF2B transcriptional activity. CABIN1 deletions enhance BCR-stimulated NFAT and MEF2B transcriptional activity, while CABIN1 mutations enhance only MEF2B transcriptional activity by impairing binding of mSin3a to CABIN1. Our data provide an unbiased identification of genetically altered genes that may play a role in the molecular pathogenesis of OAMZL and serve as therapeutic targets.


Assuntos
Neoplasias Oculares , Linfoma de Zona Marginal Tipo Células B , Humanos , Linfoma de Zona Marginal Tipo Células B/genética , Neoplasias Oculares/genética , Mutação/genética , Transdução de Sinais/genética , NF-kappa B/genética , Fatores de Transcrição MEF2/genética
11.
Heliyon ; 7(7): e07570, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34377851

RESUMO

Brain-derived neurotrophic factor (Bdnf) expression is tightly controlled at the transcriptional and post-transcriptional levels. Previously, we showed that inhibition of noncoding Bdnf antisense (Bdnf-AS) RNA upregulates Bdnf protein. Here, we generated a Bdnf-antisense knockout (Bdnf-AS KO) mouse model by deleting 6 kilobases upstream of Bdnf-AS. After verifying suppression of Bdnf-AS, baseline behavioral tests indicated no significant difference in knockout and wild type mice, except for enhanced cognitive function in the knockout mice in the Y-maze. Following acute involuntary exercise, Bdnf-AS KO mice were re-assessed and a significant increase in Bdnf mRNA and protein were observed. Following long-term involuntary exercise, we observed a significant increase in nonspatial and spatial memory in novel object recognition and Barnes maze tests in young and aged Bdnf-AS KO mice. Our data provides evidence for the beneficial effects of endogenous Bdnf upregulation and the synergistic effect of Bdnf-AS knockout on exercise and memory retention.

12.
Mol Neurobiol ; 57(5): 2279-2289, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32008165

RESUMO

Despite its heterogeneity, autism is characterized by a defined behavioral phenotype, suggesting that the molecular pathology affects specific neural substrates to cause behavioral dysfunction. Previous studies identified genes dysregulated in autism cortex but did not address their cell-type specificity. Moreover, it is unknown whether there is a core of genes dysregulated across multiple neocortical regions. We applied RNA sequencing to postmortem brain tissue samples from autism patients and neurologically normal controls and combined our data with previously published datasets. We then identified genes, pathways, and alternative splicing events which are dysregulated in five neocortical regions in autism. To gain information about cell-type specificity of the dysregulated genes, we analyzed single-nuclei RNA sequencing data of adult human cortex and intersected cell-type-specific gene signatures with genes dysregulated in autism in specific cortical regions. We found that autism-associated gene expression changes across 4 frontal and temporal cortex regions converge on 27 genes related to immune response and enriched in human astrocytes, microglia, and brain endothelium. Shared splicing changes, however, are found in genes predominantly associated with synaptic function and adult interneurons and projection neurons. Finally, we demonstrate that regions of DNA differentially methylated in autism overlap genes associated with development and enriched in human cortical oligodendrocytes. Our study identifies signatures of autism molecular pathology shared across neocortical regions, as well as neural cell types enriched for common dysregulated genes, thus paving way for assessing cell-type-specific mechanisms of autism pathology.


Assuntos
Transtorno do Espectro Autista/genética , Neocórtex/metabolismo , RNA Mensageiro/análise , Processamento Alternativo , Transtorno do Espectro Autista/patologia , Metilação de DNA , Regulação da Expressão Gênica , Ontologia Genética , Humanos , Imunidade/genética , Redes e Vias Metabólicas/genética , Neocórtex/patologia , Neuroglia/metabolismo , Neurônios/metabolismo , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/patologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de RNA , Análise de Célula Única , Sinapses/metabolismo , Lobo Temporal/metabolismo , Lobo Temporal/patologia , Transcriptoma
13.
Leukemia ; 34(2): 553-566, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31570756

RESUMO

Regulating B-cell receptor (BCR) signaling after antigenic stimulation is essential to properly control immune responses. Currently known mechanisms of inhibiting BCR signaling are via co-receptor stimulation and downstream immunoreceptor tyrosine-based inhibition motif (ITIM) phosphorylation. Herein we demonstrate that BCR stimulation induces rapid and reversible palmitoylation of the SCF-FBXO10 ubiquitin E3 ligase. This results in FBXO10 relocation to the cell membrane, where it targets the human germinal center-associated lymphoma (HGAL) protein for ubiquitylation and degradation, leading to decreases in both BCR-induced calcium influx and phosphorylation of proximal BCR effectors. Importantly, FBXO10 recognition and degradation of HGAL is phosphorylation independent and instead relies on a single evolutionarily conserved HGAL amino acid residue (H91) and FBXO10 relocalization to the cytoplasmic membrane. Together our findings demonstrate the first evidence of negative BCR signaling regulation from direct BCR stimulation and define the temporospatial functions of the FBXO10-HGAL axis. FBXO10 is infrequently mutated in DLBCL but some of these mutations deregulate BCR signaling. These observations may have important implications on lymphomagenesis and other immune processes.


Assuntos
Proteínas F-Box/metabolismo , Centro Germinativo/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas dos Microfilamentos/metabolismo , Receptores de Antígenos de Linfócitos B/metabolismo , Linfócitos B/metabolismo , Membrana Celular/metabolismo , Humanos , Linfoma Difuso de Grandes Células B/metabolismo , Proteínas de Neoplasias/metabolismo , Fosforilação/fisiologia , Transdução de Sinais/fisiologia , Ubiquitina-Proteína Ligases/metabolismo
14.
Blood Adv ; 3(15): 2286-2297, 2019 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-31362927

RESUMO

Human germinal center (GC)-associated lymphoma (HGAL) is an adaptor protein expressed in GC B cells. HGAL regulates cell motility and B-cell receptor (BCR) signaling, processes that are central for the successful completion of the GC reaction. Herein, we demonstrate phosphorylation of HGAL by Syk and Lyn kinases at tyrosines Y80, Y86, Y106Y107, Y128, and Y148. The HGAL YEN motif (amino acids 107-109) is similar to the phosphopeptide motif pYXN used as a binding site to the growth factor receptor-bound protein 2 (Grb2). We demonstrate by biochemical and molecular methodologies that HGAL directly interacts with Grb2. Concordantly, microscopy studies demonstrate HGAL-Grb2 colocalization in the membrane central supramolecular activation clusters (cSMAC) following BCR activation. Mutation of the HGAL putative binding site to Grb2 abrogates the interaction between these proteins. Further, this HGAL mutant localizes exclusively in the peripheral SMAC and decreases the rate and intensity of BCR accumulation in the cSMAC. Furthermore, we demonstrate that Grb2, HGAL, and Syk interact in the same complex, but Grb2 does not modulate the effects of HGAL on Syk kinase activity. Overall, the interplay between the HGAL and Grb2 regulates the magnitude of BCR signaling and synapse formation.


Assuntos
Linfócitos B/metabolismo , Proteína Adaptadora GRB2/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas dos Microfilamentos/metabolismo , Receptores de Antígenos de Linfócitos B/metabolismo , Transdução de Sinais , Animais , Linfócitos B/imunologia , Linhagem Celular , Camundongos , Modelos Biológicos , Fosforilação , Ligação Proteica , Quinase Syk/metabolismo , Quinases da Família src/metabolismo
15.
Methods Mol Biol ; 1543: 197-208, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28349428

RESUMO

Transcriptomic as well as in vivo studies have revealed the importance of several lncRNAs in many complex diseases including cancer, cardiovascular, and neurological disorders. In this protocol, we describe how to perform RNAseq data analysis to identify lncRNAs associated with disease states utilizing the open-source software CANEapp (application for Comprehensive automated Analysis of Next-generation sequencing Experiments).


Assuntos
Biologia Computacional/métodos , Estudos de Associação Genética , Predisposição Genética para Doença , RNA Longo não Codificante/genética , Software , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica , Estudos de Associação Genética/métodos , Humanos , Transcriptoma , Navegador
16.
World J Biol Psychiatry ; 18(6): 445-456, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-27723376

RESUMO

OBJECTIVES: We examined mechanisms that contribute to the rapid antidepressant effect of ketamine in mice that is dependent on glycogen synthase kinase-3 (GSK3) inhibition. METHODS: We measured serotonergic (5HT)-2C-receptor (5HTR2C) cluster microRNA (miRNA) levels in mouse hippocampus after administering an antidepressant dose of ketamine (10 mg/kg) in wild-type and GSK3 knockin mice, after GSK3 inhibition with L803-mts, and in learned helpless mice. RESULTS: Ketamine up-regulated cluster miRNAs 448-3p, 764-5p, 1264-3p, 1298-5p and 1912-3p (2- to 11-fold). This up-regulation was abolished in GSK3 knockin mice that express mutant constitutively active GSK3. The GSK3 specific inhibitor L803-mts was antidepressant in the learned helplessness and novelty suppressed feeding depression-like behaviours and up-regulated the 5HTR2C miRNA cluster in mouse hippocampus. After administration of the learned helplessness paradigm mice were divided into cohorts that were resilient (non-depressed) or were susceptible (depressed) to learned helplessness. The resilient, but not depressed, mice displayed increased hippocampal levels of miRNAs 448-3p and 1264-3p. Administration of an antagonist to miRNA 448-3p diminished the antidepressant effect of ketamine in the learned helplessness paradigm, indicating that up-regulation of miRNA 448-3p provides an antidepressant action. CONCLUSIONS: These findings identify a new outcome of GSK3 inhibition by ketamine that may contribute to antidepressant effects.


Assuntos
Antidepressivos/farmacologia , Comportamento Animal/efeitos dos fármacos , Quinase 3 da Glicogênio Sintase/antagonistas & inibidores , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Íntrons/efeitos dos fármacos , Ketamina/farmacologia , MicroRNAs/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Receptor 5-HT2C de Serotonina/efeitos dos fármacos , Animais , Antidepressivos/administração & dosagem , Depressão/tratamento farmacológico , Modelos Animais de Doenças , Desamparo Aprendido , Ketamina/administração & dosagem , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Oligopeptídeos/administração & dosagem , Oligopeptídeos/farmacologia , Inibidores de Proteínas Quinases/administração & dosagem , Regulação para Cima
17.
JCI Insight ; 2(6): e91782, 2017 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-28352664

RESUMO

Molecular mechanisms underlying learning and memory remain imprecisely understood, and restorative interventions are lacking. We report that intranasal administration of siRNAs can be used to identify targets important in cognitive processes and to improve genetically impaired learning and memory. In mice modeling the intellectual deficiency of Fragile X syndrome, intranasally administered siRNA targeting glycogen synthase kinase-3ß (GSK3ß), histone deacetylase-1 (HDAC1), HDAC2, or HDAC3 diminished cognitive impairments. In WT mice, intranasally administered brain-derived neurotrophic factor (BDNF) siRNA or HDAC4 siRNA impaired learning and memory, which was partially due to reduced insulin-like growth factor-2 (IGF2) levels because the BDNF siRNA- or HDAC4 siRNA-induced cognitive impairments were ameliorated by intranasal IGF2 administration. In Fmr1-/- mice, hippocampal IGF2 was deficient, and learning and memory impairments were ameliorated by IGF2 intranasal administration. Therefore intranasal siRNA administration is an effective means to identify mechanisms regulating cognition and to modulate therapeutic targets.


Assuntos
Transtornos Cognitivos/genética , Síndrome do Cromossomo X Frágil/genética , Fator de Crescimento Insulin-Like II/genética , RNA Interferente Pequeno/administração & dosagem , Administração Intranasal , Animais , Transtornos Cognitivos/psicologia , Proteína do X Frágil da Deficiência Intelectual/genética , Síndrome do Cromossomo X Frágil/psicologia , Glicogênio Sintase Quinase 3 beta/genética , Histona Desacetilases/genética , Camundongos , Camundongos Knockout
18.
Nat Commun ; 8: 15622, 2017 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-28555645

RESUMO

Long noncoding RNAs are emerging players in the epigenetic machinery with key roles in development and diseases. Here we uncover a complex network comprising a promoter-associated noncoding RNA (paRNA), microRNA and epigenetic regulators that controls transcription of the tumour suppressor E-cadherin in epithelial cancers. E-cadherin silencing relies on the formation of a complex between the paRNA and microRNA-guided Argonaute 1 that, together, recruit SUV39H1 and induce repressive chromatin modifications in the gene promoter. A single nucleotide polymorphism (rs16260) linked to increased cancer risk alters the secondary structure of the paRNA, with the risk allele facilitating the assembly of the microRNA-guided Argonaute 1 complex and gene silencing. Collectively, these data demonstrate the role of a paRNA in E-cadherin regulation and the impact of a noncoding genetic variant on its function. Deregulation of paRNA-based epigenetic networks may contribute to cancer and other diseases making them promising targets for drug discovery.


Assuntos
Proteínas Argonautas/genética , Caderinas/genética , Fatores de Iniciação em Eucariotos/genética , Inativação Gênica , Metiltransferases/genética , Neoplasias/genética , Neoplasias da Próstata/genética , Proteínas Repressoras/genética , Alelos , Antígenos CD , Diferenciação Celular , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor , Humanos , Masculino , Mutagênese Sítio-Dirigida , Conformação de Ácido Nucleico , Polimorfismo Genético , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Neoplasias da Próstata/metabolismo
19.
Curr Alzheimer Res ; 13(9): 985-95, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27117003

RESUMO

BACKGROUND: Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by welldefined neuropathological brain changes including amyloid plaques, neurofibrillary tangles and the presence of chronic neuroinflammation. OBJECTIVE: The brain penetrant BET bromodomain inhibitor JQ1 has been shown to regulate inflammation responses in vitro and in vivo, but its therapeutic potential in AD is currently unknown. METHOD: Three-month-old 3xTg mice were injected once a day with JQ1 (50 mg/kg) or vehicle for 15 weeks. At the end of the treatment learning and memory was assessed using the modified Barnes maze and the Y maze behavioral tests. Tissue from the brain and other organs was collected for molecular evaluation of neuroinflammation tau pathology and amyloid ß. RESULTS: JQ1 treatment reduced splenomegaly and neuroinflammation in the brain of treated mice where we observed a reduction in the expression of the pro-inflammatory modulators Il-1b, Il-6, Tnfa, Ccl2, Nos2 and Ptgs2. Additionally, JQ1-treated mice showed a reduction of tau phosphorylation at Ser396 in the hippocampus and frontal cortex while total levels of tau remained unaffected. On the other hand, JQ1 did not ameliorate learning and memory deficits in 7-month-old 3xTg mice. CONCLUSION: Taken together, our data suggest that BET bromodomain inhibitors hold the promise to be used for the treatment of neurological disorders characterized by neuroinflammation.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Azepinas/farmacologia , Encéfalo/efeitos dos fármacos , Inflamação/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Triazóis/farmacologia , Proteínas tau/metabolismo , Doença de Alzheimer/imunologia , Doença de Alzheimer/patologia , Doença de Alzheimer/psicologia , Peptídeos beta-Amiloides/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Encéfalo/imunologia , Encéfalo/patologia , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Inflamação/metabolismo , Inflamação/patologia , Aprendizagem/efeitos dos fármacos , Masculino , Memória/efeitos dos fármacos , Camundongos Transgênicos , Tamanho do Órgão , Fragmentos de Peptídeos/metabolismo , Fosforilação/efeitos dos fármacos , Baço/efeitos dos fármacos , Baço/imunologia , Baço/patologia
20.
J Alzheimers Dis ; 48(3): 647-65, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26402107

RESUMO

The underlying genetic variations of late-onset Alzheimer's disease (LOAD) cases remain largely unknown. A combination of genetic variations with variable penetrance and lifetime epigenetic factors may converge on transcriptomic alterations that drive LOAD pathological process. Transcriptome profiling using deep sequencing technology offers insight into common altered pathways regardless of underpinning genetic or epigenetic factors and thus represents an ideal tool to investigate molecular mechanisms related to the pathophysiology of LOAD. We performed directional RNA sequencing on high quality RNA samples extracted from hippocampi of LOAD and age-matched controls. We further validated our data using qRT-PCR on a larger set of postmortem brain tissues, confirming downregulation of the gene encoding substance P (TAC1) and upregulation of the gene encoding the plasminogen activator inhibitor-1 (SERPINE1). Pathway analysis indicates dysregulation in neural communication, cerebral vasculature, and amyloid-ß clearance. Beside protein coding genes, we identified several annotated and non-annotated long noncoding RNAs that are differentially expressed in LOAD brain tissues, three of them are activity-dependent regulated and one is induced by Aß(1-42) exposure of human neural cells. Our data provide a comprehensive list of transcriptomics alterations in LOAD hippocampi and warrant holistic approach including both coding and non-coding RNAs in functional studies aimed to understand the pathophysiology of LOAD.


Assuntos
Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , RNA Longo não Codificante/metabolismo , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/genética , Feminino , Perfilação da Expressão Gênica , Hipocampo/metabolismo , Homeostase/genética , Homeostase/fisiologia , Humanos , Masculino , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de RNA , Transcriptoma
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