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1.
BMC Psychiatry ; 23(1): 34, 2023 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-36639615

RESUMO

OBJECTIVE: To determine whether adverse childhood experiences (ACEs) of children of alcoholics (COA) in male were associated with their current "risky drinking". METHODS: This case-control study used the Alcohol Use Disorder Identification Test (AUDIT, cutoff is 7) to divide the participants into two groups, a "risky drinking" group (N = 53) and a "non-risky drinking" group (N = 97). Demographic data, Adverse Childhood Experiences-International Questionnaire (ACE-IQ), the Hamilton Anxiety Rating Scale (HAMA), the Hamilton Depression Rating Scale (HAMD) and the Mini-International Neuropsychiatric Interview (MINI) were used for assessment. The specific relationships between ACEs and "risky drinking" were explored. RESULTS: Respondents ranged in age from 29.70 ± 6.72 years; 74.5% were females; 94.7% were of Han nationality; 56.7% had a level of education above high school; 12% had no formal or stable job. There was difference in attitude to self-drinking between two groups (P < 0.001). The "risky drinking" group was more likely to have experienced a major depressive episode (P < 0.05), nonalcohol psychoactive substance use disorder (P < 0.01) and bulimia nervosa (P < 0.05), and they also experienced more physical abuse (P < 0.05), community violence (P < 0.001) and collective violence (P < 0.01). In a single factor logistic regression, physical abuse, community violence and collective violence were associated with a two to 11- fold increase in "risky drinking" in the adult COA, and in multiple factor logistic regression, community violence showed a graded relationship with "risky drinking". CONCLUSION: The childhood adverse experiences contribute to "risky drinking" in COA. This finding in the Chinese context have significant implications for prevention not only in China but in other cultures. There must be greater awareness of the role of ACEs in the perpetuation of alcoholism.


Assuntos
Experiências Adversas da Infância , Alcoolismo , Transtorno Depressivo Maior , Adulto , Criança , Feminino , Humanos , Masculino , Adulto Jovem , Alcoolismo/epidemiologia , Alcoolismo/psicologia , Estudos de Casos e Controles , Violência , Filhos Adultos
2.
Nat Cell Biol ; 20(10): 1227, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29907862

RESUMO

In the version of this Article originally published, in Fig. 2c, the '+' sign and 'OSKM' were superimposed in the label '+OSKM'. In Fig. 4e, in the labels, all instances of 'Ant' should have been 'Anti-'. And, in Fig. 7a, the label '0.0' was misplaced; it should have been on the colour scale bar. These figures have now been corrected in the online versions.

3.
Nat Cell Biol ; 20(4): 400-412, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29531310

RESUMO

Somatic cell reprogramming by exogenous factors requires cooperation with transcriptional co-activators and co-repressors to effectively remodel the epigenetic environment. How this interplay is regulated remains poorly understood. Here, we demonstrate that NCoR/SMRT co-repressors bind to pluripotency loci to create a barrier to reprogramming with the four Yamanaka factors (OCT4, SOX2, KLF4 and c-MYC), and consequently, suppressing NCoR/SMRT significantly enhances reprogramming efficiency and kinetics. The core epigenetic subunit of the NCoR/SMRT complex, histone deacetylase 3 (HDAC3), contributes to the effects of NCoR/SMRT by inducing histone deacetylation at pluripotency loci. Among the Yamanaka factors, recruitment of NCoR/SMRT-HDAC3 to genomic loci is mostly facilitated by c-MYC. Hence, we describe how c-MYC is beneficial for the early phase of reprogramming but deleterious later. Overall, we uncover a role for NCoR/SMRT co-repressors in reprogramming and propose a dual function for c-MYC in this process.


Assuntos
Reprogramação Celular , Epigênese Genética , Células-Tronco Embrionárias Murinas/metabolismo , Correpressor 1 de Receptor Nuclear/metabolismo , Correpressor 2 de Receptor Nuclear/metabolismo , Células-Tronco Pluripotentes/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Acetilação , Animais , Regulação da Expressão Gênica no Desenvolvimento , Células HEK293 , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Histonas/metabolismo , Humanos , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Correpressor 1 de Receptor Nuclear/genética , Correpressor 2 de Receptor Nuclear/genética , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Processamento de Proteína Pós-Traducional , Proteínas Proto-Oncogênicas c-myc/genética , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Transdução de Sinais , Fatores de Tempo
4.
Nat Methods ; 15(3): 213-220, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29431736

RESUMO

We combine the labeling of newly transcribed RNAs with 5-ethynyluridine with the characterization of bound proteins. This approach, named capture of the newly transcribed RNA interactome using click chemistry (RICK), systematically captures proteins bound to a wide range of RNAs, including nascent RNAs and traditionally neglected nonpolyadenylated RNAs. RICK has identified mitotic regulators amongst other novel RNA-binding proteins with preferential affinity for nonpolyadenylated RNAs, revealed a link between metabolic enzymes/factors and nascent RNAs, and expanded the known RNA-bound proteome of mouse embryonic stem cells. RICK will facilitate an in-depth interrogation of the total RNA-bound proteome in different cells and systems.


Assuntos
Química Click/métodos , Proteoma/metabolismo , Proteínas de Ligação a RNA/metabolismo , RNA/metabolismo , Animais , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Células HeLa , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Espectrometria de Massas/métodos , Camundongos , Mapas de Interação de Proteínas , RNA/genética , Proteínas de Ligação a RNA/genética , Uridina/análogos & derivados , Uridina/química
5.
Cell Discov ; 3: 17002, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28326190

RESUMO

Malat1 is one of the most abundant long non-coding RNAs in various cell types; its exact cellular function is still a matter of intense investigation. In this study we characterized the function of Malat1 in skeletal muscle cells and muscle regeneration. Utilizing both in vitro and in vivo assays, we demonstrate that Malat1 has a role in regulating gene expression during myogenic differentiation of myoblast cells. Specifically, we found that knockdown of Malat1 accelerates the myogenic differentiation in cultured cells. Consistently, Malat1 knockout mice display enhanced muscle regeneration after injury and deletion of Malat1 in dystrophic mdx mice also improves the muscle regeneration. Mechanistically, in the proliferating myoblasts, Malat1 recruits Suv39h1 to MyoD-binding loci, causing trimethylation of histone 3 lysine 9 (H3K9me3), which suppresses the target gene expression. Upon differentiation, the pro-myogenic miR-181a is increased and targets the nuclear Malat1 transcripts for degradation through Ago2-dependent nuclear RNA-induced silencing complex machinery; the Malat1 decrease subsequently leads to the destabilization of Suv39h1/HP1ß/HDAC1-repressive complex and displacement by a Set7-containing activating complex, which allows MyoD trans-activation to occur. Together, our findings identify a regulatory axis of miR-181a-Malat1-MyoD/Suv39h1 in myogenesis and uncover a previously unknown molecular mechanism of Malat1 action in gene regulation.

6.
Trends Cell Biol ; 26(4): 272-288, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26776886

RESUMO

Somatic cells and pluripotent cells display remarkable differences in most aspects of cell function. Accordingly, somatic cell reprogramming by exogenous factors requires comprehensive changes in gene transcription to induce a forced pluripotent state, which is encompassed by a simultaneous transformation of the epigenome. Nevertheless, how the reprogramming factors and other endogenous regulators coordinate to suppress the somatic cell gene program and activate the pluripotency gene network, and why the conversion is multi-phased and lengthy, remain enigmatic. We summarize the current knowledge of transcriptional regulation in somatic cell reprogramming, and highlight new perspectives that may help to reshape existing paradigms.


Assuntos
Reprogramação Celular , Células-Tronco Embrionárias/metabolismo , Epigênese Genética , Células-Tronco Pluripotentes/metabolismo , Transcrição Gênica , Diferenciação Celular , Células-Tronco Embrionárias/citologia , Regulação da Expressão Gênica no Desenvolvimento , Redes Reguladoras de Genes , Humanos , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Células-Tronco Pluripotentes/citologia , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Transdução de Sinais
7.
Nat Commun ; 6: 10026, 2015 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-26658965

RESUMO

Little is known how lincRNAs are involved in skeletal myogenesis. Here we describe the discovery of Linc-YY1 from the promoter of the transcription factor (TF) Yin Yang 1 (YY1) gene. We demonstrate that Linc-YY1 is dynamically regulated during myogenesis in vitro and in vivo. Gain or loss of function of Linc-YY1 in C2C12 myoblasts or muscle satellite cells alters myogenic differentiation and in injured muscles has an impact on the course of regeneration. Linc-YY1 interacts with YY1 through its middle domain, to evict YY1/Polycomb repressive complex (PRC2) from target promoters, thus activating the gene expression in trans. In addition, Linc-YY1 also regulates PRC2-independent function of YY1. Finally, we identify a human Linc-YY1 orthologue with conserved function and show that many human and mouse TF genes are associated with lincRNAs that may modulate their activity. Altogether, we show that Linc-YY1 regulates skeletal myogenesis and uncover a previously unappreciated mechanism of gene regulation by lincRNA.


Assuntos
Desenvolvimento Muscular/fisiologia , RNA Longo não Codificante/metabolismo , Fator de Transcrição YY1/metabolismo , Animais , Linhagem Celular , Embrião de Mamíferos , Regulação da Expressão Gênica/fisiologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos mdx , RNA Longo não Codificante/genética , Regeneração/fisiologia , Fator de Transcrição YY1/genética
8.
Cell Res ; 25(3): 335-50, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25686699

RESUMO

Emerging studies document the roles of long non-coding RNAs (LncRNAs) in regulating gene expression at chromatin level but relatively less is known how they regulate DNA methylation. Here we identify an lncRNA, Dum (developmental pluripotency-associated 2 (Dppa2) Upstream binding Muscle lncRNA) in skeletal myoblast cells. The expression of Dum is dynamically regulated during myogenesis in vitro and in vivo. It is also transcriptionally induced by MyoD binding upon myoblast differentiation. Functional analyses show that it promotes myoblast differentiation and damage-induced muscle regeneration. Mechanistically, Dum was found to silence its neighboring gene, Dppa2, in cis through recruiting Dnmt1, Dnmt3a and Dnmt3b. Furthermore, intrachromosomal looping between Dum locus and Dppa2 promoter is necessary for Dum/Dppa2 interaction. Collectively, we have identified a novel lncRNA that interacts with Dnmts to regulate myogenesis.


Assuntos
DNA (Citosina-5-)-Metiltransferases/genética , Desenvolvimento Muscular/genética , Proteínas Nucleares/biossíntese , RNA Longo não Codificante/genética , Animais , Diferenciação Celular/genética , Linhagem Celular , DNA (Citosina-5-)-Metiltransferase 1 , Metilação de DNA/genética , DNA Metiltransferase 3A , Camundongos , Camundongos Endogâmicos C57BL , Desenvolvimento Muscular/fisiologia , Músculo Esquelético/citologia , Músculo Esquelético/crescimento & desenvolvimento , Proteína MyoD/genética , Proteína MyoD/metabolismo , Mioblastos/citologia , Proteínas Nucleares/genética , Cultura Primária de Células , Regiões Promotoras Genéticas/genética , Interferência de RNA , RNA Interferente Pequeno , Regeneração/genética , Regeneração/fisiologia , Fatores de Transcrição , DNA Metiltransferase 3B
9.
Cell Res ; 25(1): 80-92, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25512341

RESUMO

Recent studies have boosted our understanding of long noncoding RNAs (lncRNAs) in numerous biological processes, but few have examined their roles in somatic cell reprogramming. Through expression profiling and functional screening, we have identified that the large intergenic noncoding RNA p21 (lincRNA-p21) impairs reprogramming. Notably, lincRNA-p21 is induced by p53 but does not promote apoptosis or cell senescence in reprogramming. Instead, lincRNA-p21 associates with the H3K9 methyltransferase SETDB1 and the maintenance DNA methyltransferase DNMT1, which is facilitated by the RNA-binding protein HNRNPK. Consequently, lincRNA-p21 prevents reprogramming by sustaining H3K9me3 and/or CpG methylation at pluripotency gene promoters. Our results provide insight into the role of lncRNAs in reprogramming and establish a novel link between p53 and heterochromatin regulation.


Assuntos
Reprogramação Celular , Ilhas de CpG , Metilação de DNA , Células-Tronco Pluripotentes Induzidas/metabolismo , RNA Longo não Codificante/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Apoptose , Proliferação de Células , DNA (Citosina-5-)-Metiltransferase 1 , DNA (Citosina-5-)-Metiltransferases/metabolismo , Heterocromatina/genética , Heterocromatina/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/genética , Histonas/metabolismo , Células-Tronco Pluripotentes Induzidas/citologia , Camundongos , Regiões Promotoras Genéticas
10.
Curr Opin Cell Biol ; 25(2): 208-14, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23332905

RESUMO

The generation of induced pluripotent stem (iPS) cells by exogenous transcription factors involves a comprehensive rearrangement of cellular functions, including the microRNA profile. The resulting cell lines are similar to embryonic stem (ES) cells and have therefore raised much interest for in vitro studies and the perspective of clinical application. Yet, microRNAs are not mere listeners of the reprogramming orchestra but play an active role in the process. In consequence, overexpression or suppression of individual microRNAs has profound effects in colony formation efficiency, and in combination they can produce iPS cells without added transcription factors. Moreover, variations in microRNA expression of iPS/ES cells can predict their differentiation potential and may have consequences at other levels. Altogether, these findings highlight the relevance of pursuing further these studies.


Assuntos
Reprogramação Celular , MicroRNAs/genética , Animais , Diferenciação Celular/genética , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , MicroRNAs/metabolismo , Fatores de Transcrição/metabolismo
11.
Immunol Lett ; 105(1): 55-60, 2006 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-16481046

RESUMO

In an attempt to define the binding of staphylococcal enterotoxin D (SED) to the T cell receptor Vbeta (TCR Vbeta) and major histocompatibility complex (MHC) class II molecules, site-directed mutagenesis has been used to introduce alanine substitutions at Asn23, Phe45, Leu59, Asn61, Ile92 and Phe203 in SED. SED-N23A (SEA with Asn23 replaced with alanine) and SED-F45A mutants exhibit a significantly reduced ability to induce T cell proliferation. However, SED-L59A, SED-N61A, SED-I92A and SED-F203A mutants exhibit the normal mitogenic activity. The ability binding to MHC class II and the TCR Vbeta specificity of SED-N23A and SED-F45A were then detected. SED-N23A, but not SED-F45A, was able to compete effectively with FITC-conjugated SED for binding to Raji cells. This finding indicates that the mitogenic activity defection of SED-N23A is not due to poor binding to SED-MHC class II molecules. When stimulated with SED-N23A, T cells bearing TCR Vbeta5 were significantly reduced. When stimulated with SED-F45A, T cells bearing TCR Vbeta5, TCR Vbeta8 and TCR Vbeta12.1 were all significantly reduced. These results suggest Asn23 is an important residue involved SED interacting with TCR Vbeta; Phe45 is required for effective interaction with MHC class II molecules; and the ability of SED stimulating certain TCR Vbeta+ T cells is dependent on Phe45 binding to MHC class II molecules.


Assuntos
Enterotoxinas/genética , Enterotoxinas/metabolismo , Antígenos de Histocompatibilidade Classe II/metabolismo , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Substituição de Aminoácidos , Sequência de Bases , Sítios de Ligação/genética , DNA Bacteriano/genética , Enterotoxinas/química , Enterotoxinas/toxicidade , Humanos , Técnicas In Vitro , Ativação Linfocitária/efeitos dos fármacos , Modelos Moleculares , Mutagênese Sítio-Dirigida , Mutação , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia
12.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 20(6): 757-9, 2004 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-15555455

RESUMO

AIM: To study TCR Vbeta binding sites of staphylococcal enterotoxin D(SED). METHODS: Six SED mutants were constructed by site-directed mutagenesis. The activity of promoting T cell proliferation by the mutants was detected by (3)H-TdR incorporation. For the mutants with decreased mitogenic activity, flow cytometry was used detect their MHC-II binding activity and TCR Vbeta specificity. RESULTS: Residue N23 played an important role in the interaction of SED with human TCR Vbeta5. Residue H26 was probably a SED binding site to human TCR Vbetas except for TCR Vbeta5, TCR Vbeta8 and TCR Vbeta12.1. CONCLUSION: Residue N23 is a key TCR Vbeta binding site of SED.


Assuntos
Enterotoxinas/metabolismo , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Staphylococcus aureus/imunologia , Superantígenos/metabolismo , Linfócitos T/citologia , Sítios de Ligação , Ligação Competitiva , Linhagem Celular Tumoral , Proliferação de Células , Enterotoxinas/genética , Enterotoxinas/imunologia , Genes MHC da Classe II , Humanos , Linfoma de Células B/patologia , Mutação , Superantígenos/genética , Superantígenos/imunologia
13.
Mol Immunol ; 41(1): 1-8, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15140570

RESUMO

Superantigens, like staphylococcal enterotoxin A (SEA), induce a strong proliferative response followed by clonal deletion of a substantial portion of defined V(beta) T-cells. The remaining cells display in vitro anergy. Anergy is a major mechanism to ensure antigen-specific tolerance in T-lymphocyte in the adult. Co-stimulatory molecules B7-1 (CD80)/B7-2 (CD86) and their counter-receptors CD28/CTLA-4 play pivotal roles in T-cell activation and immune regulation. While increasing data further suggested a role for CTLA-4 in regulating T-cell tolerance in vivo, the mechanism by which CTLA-4 influences T-lymphocyte tolerance is unclear. In the present study, we established an in vitro anergy model using superantigen SEA as the anergizing agents and examined CD3, CD28 and CTLA-4 expression of anergic T-cells in response to SEA rechallenge. It is found that anergic T-cell fails to produce the autocrine growth factor interleukin-2 (IL-2) upon stimulation, and addition of exogenous IL-2 can reverse the anergic state. Both TCR/CD3 complex and CD28 expression is not reduced in anergic cells during whole immune response, but the expression of CTLA-4 on the cell surface is enhanced dramatically in the late stages of an immune response. Using CTLA-4/B7-blocking agent, we found T-cell anergy was aborted and anergic T-cells restored the ability to proliferate and produce IL-2, suggesting that CTLA-4 may play a critical role in the induction of T-cell anergy.


Assuntos
Antígenos de Diferenciação/fisiologia , Anergia Clonal , Enterotoxinas/farmacologia , Superantígenos/farmacologia , Linfócitos T/imunologia , Antígenos CD , Antígenos CD28/metabolismo , Complexo CD3/metabolismo , Antígeno CTLA-4 , Linhagem Celular , Humanos , Ativação Linfocitária , Linfócitos T/efeitos dos fármacos
14.
Zhonghua Shao Shang Za Zhi ; 18(6): 358-61, 2002 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-12641988

RESUMO

OBJECTIVE: To explore the postburn adhesion properties of polymorphonuclear leukocyte (PMN) onto pulmonary vascular endothelial cells (PVEC) in burn patients with acute lung injury (ALI), so as to determine the role of C5a on PVEC-PMN adhesion. METHODS: Microtubule sucking technique was employed to determine the PVEC-PMN adhesion. The myeloperoxidase (MPO) was also assayed to reflect the magnitude of PVEC-PMN adhesion. RESULTS: The magnitude of PVEC-PMN adhesion increased and the adhesion force increased along with an increase in rh-C5a concentration. Simultaneously, the MPO activity was increased, which could be inhibited by anti-C5aR McAb in a concentration 1:104. CONCLUSION: Both C5a and C5aR participated in PVEC-PMN adhesion, which might be important in the pathogenesis of ALI.


Assuntos
Queimaduras/sangue , Complemento C5a/farmacologia , Endotélio Vascular/efeitos dos fármacos , Pneumopatias/complicações , Neutrófilos/efeitos dos fármacos , Doença Aguda , Anticorpos Monoclonais/farmacologia , Antígenos CD/imunologia , Queimaduras/complicações , Adesão Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Endotélio Vascular/citologia , Feto , Humanos , Pulmão , Neutrófilos/citologia , Neutrófilos/enzimologia , Peroxidase/antagonistas & inibidores , Peroxidase/efeitos dos fármacos , Peroxidase/metabolismo , Receptor da Anafilatoxina C5a , Receptores de Complemento/imunologia
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