Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
2.
Mol Cell Biol ; 36(24): 3033-3047, 2016 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-27697859

RESUMO

Maintenance of cell type identity is crucial for health, yet little is known of the regulation that sustains the long-term stability of differentiated phenotypes. To investigate the roles that key transcriptional regulators play in adult differentiated cells, we examined the effects of depletion of the developmental master regulator PTF1A on the specialized phenotype of the adult pancreatic acinar cell in vivo Transcriptome sequencing and chromatin immunoprecipitation sequencing results showed that PTF1A maintains the expression of genes for all cellular processes dedicated to the production of the secretory digestive enzymes, a highly attuned surveillance of unfolded proteins, and a heightened unfolded protein response (UPR). Control by PTF1A is direct on target genes and indirect through a ten-member transcription factor network. Depletion of PTF1A causes an imbalance that overwhelms the UPR, induces cellular injury, and provokes acinar metaplasia. Compromised cellular identity occurs by derepression of characteristic stomach genes, some of which are also associated with pancreatic ductal cells. The loss of acinar cell homeostasis, differentiation, and identity is directly relevant to the pathologies of pancreatitis and pancreatic adenocarcinoma.


Assuntos
Células Acinares/citologia , Perfilação da Expressão Gênica/métodos , Pâncreas Exócrino/citologia , Fatores de Transcrição/genética , Transcrição Gênica , Células Acinares/metabolismo , Animais , Diferenciação Celular , Regulação da Expressão Gênica , Técnicas de Inativação de Genes , Homeostase , Camundongos , Pâncreas Exócrino/metabolismo , Desdobramento de Proteína , Análise de Sequência de RNA/métodos , Fatores de Transcrição/metabolismo , Resposta a Proteínas não Dobradas
3.
Nat Biotechnol ; 32(1): 76-83, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24240391

RESUMO

Reprogramming of pancreatic exocrine cells into cells resembling beta cells may provide a strategy for treating diabetes. Here we show that transient administration of epidermal growth factor and ciliary neurotrophic factor to adult mice with chronic hyperglycemia efficiently stimulates the conversion of terminally differentiated acinar cells to beta-like cells. Newly generated beta-like cells are epigenetically reprogrammed, functional and glucose responsive, and they reinstate normal glycemic control for up to 248 d. The regenerative process depends on Stat3 signaling and requires a threshold number of Neurogenin 3 (Ngn3)-expressing acinar cells. In contrast to previous work demonstrating in vivo conversion of acinar cells to beta-like cells by viral delivery of exogenous transcription factors, our approach achieves acinar-to-beta-cell reprogramming through transient cytokine exposure rather than genetic modification.


Assuntos
Fator Neurotrófico Ciliar/administração & dosagem , Diabetes Mellitus/tratamento farmacológico , Fator de Crescimento Epidérmico/administração & dosagem , Células Secretoras de Insulina/efeitos dos fármacos , Células Acinares/efeitos dos fármacos , Células Acinares/patologia , Animais , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Fator Neurotrófico Ciliar/genética , Diabetes Mellitus/genética , Fator de Crescimento Epidérmico/genética , Hiperglicemia/tratamento farmacológico , Células Secretoras de Insulina/patologia , Camundongos , Camundongos Endogâmicos NOD/genética , Transdução de Sinais
4.
Dev Cell ; 27(3): 278-92, 2013 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-24229643

RESUMO

The prospective white matter (PWM) in the nascent cerebellum contains a transient germinal compartment that produces all postnatally born GABAergic inhibitory interneurons and astrocytes. However, little is known about the molecular identity and developmental potential of resident progenitors or key regulatory niche signals. Here, we show that neural stem-cell-like primary progenitors (Tnc(YFP-low) CD133(+)) generate intermediate astrocyte (Tnc(YFP-low) CD15(+)) precursors and GABAergic transient amplifying (Ptf1a(+)) cells. Interestingly, these lineally related but functionally divergent progenitors commonly respond to Sonic hedgehog (Shh), and blockade of reception in TNC(YFP-low) cells attenuates proliferation in the PWM, reducing both intermediate progenitor classes. Furthermore, we show that Shh produced from distant Purkinje neurons maintains the PWM niche independently of its classical role in regulating granule cell precursor proliferation. Our results indicate that Purkinje neurons maintain a bidirectional signaling axis, driving the production of spatially and functionally opposed inhibitory and excitatory interneurons important for motor learning and cognition.


Assuntos
Diferenciação Celular , Cerebelo/citologia , Proteínas Hedgehog/metabolismo , Células-Tronco Neurais/citologia , Neurônios/citologia , Células de Purkinje/citologia , Animais , Astrócitos/citologia , Astrócitos/metabolismo , Proliferação de Células , Células Cultivadas , Cerebelo/metabolismo , Citometria de Fluxo , Proteínas Hedgehog/genética , Técnicas Imunoenzimáticas , Camundongos , Camundongos Knockout , Células-Tronco Neurais/metabolismo , Neurônios/metabolismo , Células de Purkinje/metabolismo , RNA Mensageiro , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Ácido gama-Aminobutírico/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...