Precommitment low-level Neurog3 expression defines a long-lived mitotic endocrine-biased progenitor pool that drives production of endocrine-committed cells.
Genes Dev
; 30(16): 1852-65, 2016 08 15.
Article
em En
| MEDLINE
| ID: mdl-27585590
ABSTRACT
The current model for endocrine cell specification in the pancreas invokes high-level production of the transcription factor Neurogenin 3 (Neurog3) in Sox9(+) bipotent epithelial cells as the trigger for endocrine commitment, cell cycle exit, and rapid delamination toward proto-islet clusters. This model posits a transient Neurog3 expression state and short epithelial residence period. We show, however, that a Neurog3(TA.LO) cell population, defined as Neurog3 transcriptionally active and Sox9(+) and often containing nonimmunodetectable Neurog3 protein, has a relatively high mitotic index and prolonged epithelial residency. We propose that this endocrine-biased mitotic progenitor state is functionally separated from a pro-ductal pool and endows them with long-term capacity to make endocrine fate-directed progeny. A novel BAC transgenic Neurog3 reporter detected two types of mitotic behavior in Sox9(+) Neurog3(TA.LO) progenitors, associated with progenitor pool maintenance or derivation of endocrine-committed Neurog3(HI) cells, respectively. Moreover, limiting Neurog3 expression dramatically increased the proportional representation of Sox9(+) Neurog3(TA.LO) progenitors, with a doubling of its mitotic index relative to normal Neurog3 expression, suggesting that low Neurog3 expression is a defining feature of this cycling endocrine-biased state. We propose that Sox9(+) Neurog3(TA.LO) endocrine-biased progenitors feed production of Neurog3(HI) endocrine-committed cells during pancreas organogenesis.
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Texto completo:
1
Bases de dados:
MEDLINE
Assunto principal:
Células-Tronco
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Regulação da Expressão Gênica no Desenvolvimento
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Fatores de Transcrição Hélice-Alça-Hélice Básicos
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Células Endócrinas
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Proteínas do Tecido Nervoso
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
Genes Dev
Assunto da revista:
BIOLOGIA MOLECULAR
Ano de publicação:
2016
Tipo de documento:
Article