Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Therapie ; 77(1): 19-24, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35148896

RESUMO

Ten years after the launch of the Future Investment Program (Programme d'Investissement d'Avenir, PIA) and the implementation of these tools, one of Giens' roundtable workshop wanted to further explore the impact of PIA on health research and innovation with the aim of preparing action reports (bibliometrics, valuation, reputation) based on 2019 findings and the history of PIA deployment in relation to the healthcare sector; to analyze the development of the industrial sector vis-a-vis the PIA actions and to examine how the specific actions and the healthcare sector in general were able to duly articulate themselves, or, take form, given existing structures or organizations and contribute to site policies through Idex/Isite. Five success keys have been identified, which should serve as a strategic compass for future action plans to develop health innovation: Full trust governance between the project manager and the institution, driven by project objectives; An increased role of universities in the steering of PIA objects, joining together in a federation, in a site policy with the Hospital University Centres and Public Scientific and Technological Establishments; A simplification of public/private partnership schemes, in the nature of the Assessment and Action Plans, and in the responsiveness of the institutions; help with the development of local ecosystems, the fostering and support of young researchers; early cross-fertilization between the academic and industrial worlds.


Assuntos
Ecossistema , Universidades , Humanos , Pesquisadores
3.
Cancer Res ; 66(10): 5069-76, 2006 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-16707429

RESUMO

Recently, we have shown implication of Brm, the catalytic subunit of the SWI/SNF chromatin remodeling complex, in repression of cyclin A expression in quiescent cells. Here, we have examined the fate of cells lacking Brm throughout the cycle. We find that despite elevated levels of cyclins A and E, these cells can respond to serum starvation, however, without reaching a canonical G(0) phase as they continue to express high levels of c-Myc and have an abnormally large average size. The response to serum starvation can be correlated with increased levels of Rb proteins p130 and p107 as well as increased association of p27 with the cyclin-dependent kinases, possibly compensating for the higher levels of G(1) cyclins by reducing their associated kinase activity. After serum stimulation, reentry into the cycle occurs normally, but the S phase is delayed and shorter. In addition, the M phase has an increased duration, and we observed frequent faulty chromosome segregation events in anaphase. Altogether, our data suggest that cells can partially overcome the absence of Brm by activating several compensatory mechanisms to control the cell cycle. However, they remain profoundly affected, unable to enter a canonical quiescent state, presenting a shorter S phase, and finally unable to perform correct chromosome segregation.


Assuntos
Processos de Crescimento Celular/fisiologia , Fibroblastos/citologia , Fatores de Transcrição/fisiologia , Células 3T3 , Animais , Ciclo Celular/genética , Ciclo Celular/fisiologia , Divisão Celular/genética , Divisão Celular/fisiologia , Processos de Crescimento Celular/genética , Segregação de Cromossomos , Fase G2/genética , Fase G2/fisiologia , Regulação da Expressão Gênica , Camundongos , Mitose/genética , Mitose/fisiologia , Fatores de Transcrição/deficiência , Fatores de Transcrição/genética
4.
J Virol ; 80(8): 3833-43, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16571800

RESUMO

Levels of the p53 tumor suppressor protein are increased in human cytomegalovirus (HCMV)-infected cells and may be important for HCMV pathogenesis. In normal cells p53 levels are kept low due to an autoregulatory feedback loop where p53 activates the transcription of mdm2 and mdm2 binds and ubiquitinates p53, targeting p53 for proteasomal degradation. Here we report that, in contrast to uninfected cells, mdm2 was undetectable upon treatment of infected fibroblasts with the proteasome inhibitor MG132. Cellular depletion of mdm2 was reproducible in p53-null cells transfected with the HCMV IE2-86 protein, but not with IE172, independently of the endogenous mdm2 promoter. IE2-86 also prevented the emergence of presumably ubiquitinated species of p53. The regions of IE2-86 important for mdm2 depletion were those containing the sequences corresponding to the putative zinc finger and C-terminal acidic motifs. mdm2 and IE2-86 coimmunoprecipitated in transfected and infected cell lysates and in a cell-free system. IE2-86 blocked mdm2's p53-independent transactivation of the cyclin A promoter in transient-transfection experiments. Pulse-chase experiments revealed that IE2-86 but not IE1-72 or several loss-of-function IE2-86 mutants increased the half-life of p53 and reduced the half-life of mdm2. Short interfering RNA-mediated depletion of IE2-86 restored the ability of HCMV-infected cells to accumulate mdm2 in response to proteasome inhibition. Taken together, the data suggest that specific interactions between IE2-86 and mdm2 cause proteasome-independent degradation of mdm2 and that this may be important for the accumulation of p53 in HCMV-infected cells.


Assuntos
Proteínas Imediatamente Precoces/fisiologia , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Transativadores/fisiologia , Sequência de Aminoácidos , Animais , Células Cultivadas , Cricetinae , Ciclina A/genética , Meia-Vida , Humanos , Leupeptinas/farmacologia , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Ativação Transcricional , Proteína Supressora de Tumor p53/metabolismo , Ubiquitina/metabolismo
5.
Mol Cell ; 15(1): 43-56, 2004 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-15225547

RESUMO

Cell cycle-dependent expression of cyclin A is controlled by transcriptional repression in early phase of the cell cycle. In this study, we directly examine the chromatin structure of the mouse cyclin A promoter through in vivo micrococcal nuclease footprinting. We describe here that cyclin A repression is associated with two positioned nucleosomes and that histones progressively lose DNA contact synchronously with gene activation. This particular nucleosomal organization is disrupted by mutations of the cyclin A bipartite repressor sequence. Moreover, the same sequence recruits the chromatin remodeling factor Brahma/SNF2alpha (Brm) onto the cyclin A promoter. Accordingly, cyclin A proximal promoter is not wrapped around nucleosomes and not repressed in quiescent cells lacking Brm. These results provide molecular explanations for the transcriptional repression state of cyclin A, as well as insights into the action of Brm chromatin remodeling factor as cell cycle regulator.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Ciclo Celular/genética , Montagem e Desmontagem da Cromatina/genética , Ciclina A/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas Nucleares , Regiões Promotoras Genéticas/genética , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Animais , Proteínas de Ciclo Celular/genética , DNA/genética , DNA/metabolismo , DNA Helicases , Proteínas de Ligação a DNA/genética , Proteínas de Drosophila , Histonas/genética , Histonas/metabolismo , Camundongos , Mutação/genética , Nucleossomos/genética , Nucleossomos/metabolismo , Proteínas Repressoras/genética , Elementos Silenciadores Transcricionais/genética , Células Swiss 3T3 , Transativadores/genética , Fatores de Transcrição/genética
6.
Mol Cell Biol ; 22(22): 7769-79, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12391146

RESUMO

Cyclin D1, the regulatory subunit for mid-G(1) cyclin-dependent kinases, controls the expression of numerous cell cycle genes. A cyclic AMP-responsive element (CRE), located upstream of the cyclin D1 mRNA start site, integrates mitogenic signals that target the CRE-binding factor CREB, which can recruit the transcriptional coactivator CREB-binding protein (CBP). We describe an alternative mechanism for CREB-driven cyclin D1 induction that involves the ubiquitous POU domain protein Oct-1. In the breast cancer cell line MCF-7, overexpression of Oct-1 or its POU domain strongly increases transcriptional activation of cyclin D1 and GAL4 reporter genes that is specifically dependent upon CREB but independent of Oct-1 DNA binding. Gel retardation and chromatin immunoprecipitation assays confirm that POU forms a complex with CREB bound to the cyclin D1 CRE. In solution, CREB interaction with POU requires the CREB Q2 domain and, notably, occurs with CREB that is not phosphorylated on Ser 133. Accordingly, Oct-1 also potently enhances transcriptional activation mediated by a Ser133Ala CREB mutant. Oct-1/CREB synergy is not diminished by the adenovirus E1A 12S protein, a repressor of CBP coactivator function. In contrast, E1A strongly represses CBP-enhanced transactivation by CREB phosphorylated on Ser 133. Our observation that Oct-1 potentiates CREB-dependent cyclin D1 transcriptional activity independently of Ser 133 phosphorylation and E1A-sensitive coactivator function offers a new paradigm for the regulation of cyclin D1 induction by proliferative signals.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Ciclina D1/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas Nucleares/metabolismo , Regiões Promotoras Genéticas , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Neoplasias da Mama , Proteína de Ligação a CREB , Ciclina D1/metabolismo , Genes Reporter , Fator C1 de Célula Hospedeira , Humanos , Fator 1 de Transcrição de Octâmero , Fosfoproteínas/metabolismo , Ligação Proteica , Estrutura Terciária de Proteína , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Transcrição Gênica , Células Tumorais Cultivadas
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...