Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Cell ; 149(7): 1635-46, 2012 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-22608085

RESUMO

Methylation of the N(6) position of adenosine (m(6)A) is a posttranscriptional modification of RNA with poorly understood prevalence and physiological relevance. The recent discovery that FTO, an obesity risk gene, encodes an m(6)A demethylase implicates m(6)A as an important regulator of physiological processes. Here, we present a method for transcriptome-wide m(6)A localization, which combines m(6)A-specific methylated RNA immunoprecipitation with next-generation sequencing (MeRIP-Seq). We use this method to identify mRNAs of 7,676 mammalian genes that contain m(6)A, indicating that m(6)A is a common base modification of mRNA. The m(6)A modification exhibits tissue-specific regulation and is markedly increased throughout brain development. We find that m(6)A sites are enriched near stop codons and in 3' UTRs, and we uncover an association between m(6)A residues and microRNA-binding sites within 3' UTRs. These findings provide a resource for identifying transcripts that are substrates for adenosine methylation and reveal insights into the epigenetic regulation of the mammalian transcriptome.


Assuntos
Regiões 3' não Traduzidas , Códon de Terminação , Processamento Pós-Transcricional do RNA , Transcriptoma , Adenosina/metabolismo , Metilação , RNA Mensageiro/metabolismo , RNA não Traduzido/metabolismo
2.
RNA Biol ; 10(3): 342-6, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23434792

RESUMO

Methyl-6-adenosine (m (6)A) has been hypothesized to exist since the 1970s, (1) but little has been known about the specific RNAs, or sites within them, that are affected by this RNA modification. Here, we report that recent work has shown RNA modifications like m (6)A, collectively called the "epitranscriptome," are a pervasive feature of mammalian cells and likely play a role in development and disease. An enrichment of m (6)A near the last CDS of thousands of genes has implicated m (6)A in transcript processing, translational regulation and potentially a mechanism for regulating miRNA maturation. Also, because the sites of m (6)A show strong evolutionary conservation and have been replicated in nearly identical sites between mouse and human, strong evolutionary pressures are likely being maintained for this mark. (2)(,) (3) Finally, we note that m (6)A is one of over 100 modifications of RNA that have been reported, (4) and with the combination of high-throughput, next-generation sequencing (NGS) techniques, immunoprecipitation with appropriate antibodies and splicing-aware peak-finding, the dynamics of the epitranscriptome can now be mapped and characterized to discern their specific cellular roles.


Assuntos
Adenosina/análogos & derivados , MicroRNAs/metabolismo , Estabilidade de RNA , Transcriptoma , Adenosina/metabolismo , Animais , Sítios de Ligação , Epigênese Genética , Epigenômica , Regulação da Expressão Gênica , Genoma , Células HEK293 , Humanos , Camundongos , MicroRNAs/genética
3.
Nat Med ; 23(11): 1369-1376, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28920958

RESUMO

N6-methyladenosine (m6A) is an abundant nucleotide modification in mRNA that is required for the differentiation of mouse embryonic stem cells. However, it remains unknown whether the m6A modification controls the differentiation of normal and/or malignant myeloid hematopoietic cells. Here we show that shRNA-mediated depletion of the m6A-forming enzyme METTL3 in human hematopoietic stem/progenitor cells (HSPCs) promotes cell differentiation, coupled with reduced cell proliferation. Conversely, overexpression of wild-type METTL3, but not of a catalytically inactive form of METTL3, inhibits cell differentiation and increases cell growth. METTL3 mRNA and protein are expressed more abundantly in acute myeloid leukemia (AML) cells than in healthy HSPCs or other types of tumor cells. Furthermore, METTL3 depletion in human myeloid leukemia cell lines induces cell differentiation and apoptosis and delays leukemia progression in recipient mice in vivo. Single-nucleotide-resolution mapping of m6A coupled with ribosome profiling reveals that m6A promotes the translation of c-MYC, BCL2 and PTEN mRNAs in the human acute myeloid leukemia MOLM-13 cell line. Moreover, loss of METTL3 leads to increased levels of phosphorylated AKT, which contributes to the differentiation-promoting effects of METTL3 depletion. Overall, these results provide a rationale for the therapeutic targeting of METTL3 in myeloid leukemia.


Assuntos
Adenosina/análogos & derivados , Células da Medula Óssea/citologia , Diferenciação Celular/fisiologia , Leucemia Mieloide Aguda/patologia , Metiltransferases/fisiologia , Adenosina/biossíntese , Células Cultivadas , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Humanos , Células Tumorais Cultivadas
4.
Nat Microbiol ; 1: 16011, 2016 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-27572442

RESUMO

N(6)-methyladenosine (m(6)A) is the most prevalent internal modification of eukaryotic mRNA. Very little is known of the function of m(6)A in the immune system or its role in host-pathogen interactions. Here, we investigate the topology, dynamics and bidirectional influences of the viral-host RNA methylomes during HIV-1 infection of human CD4 T cells. We show that viral infection triggers a massive increase in m(6)A in both host and viral mRNAs. In HIV-1 mRNA, we identified 14 methylation peaks in coding and noncoding regions, splicing junctions and splicing regulatory sequences. We also identified a set of 56 human gene transcripts that were uniquely methylated in HIV-1-infected T cells and were enriched for functions in viral gene expression. The functional relevance of m(6)A for viral replication was demonstrated by silencing of the m(6)A writer or the eraser enzymes, which decreased or increased HIV-1 replication, respectively. Furthermore, methylation of two conserved adenosines in the stem loop II region of HIV-1 Rev response element (RRE) RNA enhanced binding of HIV-1 Rev protein to the RRE in vivo and influenced nuclear export of RNA. Our results identify a new mechanism for the control of HIV-1 replication and its interaction with the host immune system.


Assuntos
Adenosina/análogos & derivados , Linfócitos T CD4-Positivos/química , Linfócitos T CD4-Positivos/virologia , HIV-1/crescimento & desenvolvimento , Interações Hospedeiro-Patógeno , RNA Mensageiro/análise , Adenosina/análise , Linhagem Celular , Humanos
5.
Cell Syst ; 1(1): 72-87, 2015 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-26594662

RESUMO

The panoply of microorganisms and other species present in our environment influence human health and disease, especially in cities, but have not been profiled with metagenomics at a city-wide scale. We sequenced DNA from surfaces across the entire New York City (NYC) subway system, the Gowanus Canal, and public parks. Nearly half of the DNA (48%) does not match any known organism; identified organisms spanned 1,688 bacterial, viral, archaeal, and eukaryotic taxa, which were enriched for harmless genera associated with skin (e.g., Acinetobacter). Predicted ancestry of human DNA left on subway surfaces can recapitulate U.S. Census demographic data, and bacterial signatures can reveal a station's history, such as marine-associated bacteria in a hurricane-flooded station. Some evidence of pathogens was found (Bacillus anthracis), but a lack of reported cases in NYC suggests that the pathogens represent a normal, urban microbiome. This baseline metagenomic map of NYC could help long-term disease surveillance, bioterrorism threat mitigation, and health management in the built environment of cities.

6.
Nat Neurosci ; 16(8): 1042-8, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23817550

RESUMO

Dopaminergic (DA) signaling governs the control of complex behaviors, and its deregulation has been implicated in a wide range of diseases. Here we demonstrate that inactivation of the Fto gene, encoding a nucleic acid demethylase, impairs dopamine receptor type 2 (D2R) and type 3 (D3R) (collectively, 'D2-like receptor')-dependent control of neuronal activity and behavioral responses. Conventional and DA neuron-specific Fto knockout mice show attenuated activation of G protein-coupled inwardly-rectifying potassium (GIRK) channel conductance by cocaine and quinpirole. Impaired D2-like receptor-mediated autoinhibition results in attenuated quinpirole-mediated reduction of locomotion and an enhanced sensitivity to the locomotor- and reward-stimulatory actions of cocaine. Analysis of global N(6)-methyladenosine (m(6)A) modification of mRNAs using methylated RNA immunoprecipitation coupled with next-generation sequencing in the midbrain and striatum of Fto-deficient mice revealed increased adenosine methylation in a subset of mRNAs important for neuronal signaling, including many in the DA signaling pathway. Several proteins encoded by these mRNAs had altered expression levels. Collectively, FTO regulates the demethylation of specific mRNAs in vivo, and this activity relates to the control of DA transmission.


Assuntos
Dopamina/fisiologia , Neurônios Dopaminérgicos/enzimologia , Mesencéfalo/fisiologia , Oxigenases de Função Mista/fisiologia , Oxo-Ácido-Liases/fisiologia , Adenina/metabolismo , Dioxigenase FTO Dependente de alfa-Cetoglutarato , Animais , Cocaína/farmacologia , Corpo Estriado/fisiologia , Neurônios Dopaminérgicos/fisiologia , Comportamento Exploratório/efeitos dos fármacos , Comportamento Exploratório/fisiologia , Feminino , Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G/fisiologia , Locomoção/efeitos dos fármacos , Locomoção/fisiologia , Masculino , Metilação , Metiltransferases/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Oxigenases de Função Mista/deficiência , Oxigenases de Função Mista/genética , Oxo-Ácido-Liases/deficiência , Oxo-Ácido-Liases/genética , Fenótipo , Quimpirol/farmacologia , Processamento Pós-Transcricional do RNA , RNA Mensageiro/metabolismo , Receptores de Dopamina D2/deficiência , Receptores de Dopamina D2/fisiologia , Receptores de Dopamina D3/fisiologia , Recompensa , Transdução de Sinais/efeitos dos fármacos
7.
Genome Biol ; 13(10): 175, 2012 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-23113984

RESUMO

Recent studies have found methyl-6-adenosine in thousands of mammalian genes, and this modification is most pronounced near the beginning of the 3' UTR. We present a perspective on current work and new single-molecule sequencing methods for detecting RNA base modifications.


Assuntos
Adenosina/metabolismo , Epigenômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Processamento Pós-Transcricional do RNA , RNA/metabolismo , Regiões 3' não Traduzidas , Animais , Células HEK293 , Células Hep G2 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Transcriptoma
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa