Overexpression of miR-122 promotes the hepatic differentiation and maturation of mouse ESCs through a miR-122/FoxA1/HNF4a-positive feedback loop.
Liver Int
; 34(2): 281-95, 2014 Feb.
Article
en En
| MEDLINE
| ID: mdl-23834235
ABSTRACT
BACKGROUND & AIMS:
microRNA-122 is the only identified liver-specific miRNA and plays a crucial role in liver development, maintenance of hepatic homeostasis as well as tumourigenesis. In our previous differentiation of ESCs into hepatocytes, microRNA-122 (miR-122) was expressed at a relatively low level. Here, we aim to elucidate the effect and underlying mechanisms of miR-122 during differentiation of ESCs into hepatocytes.METHODS:
Mouse ESCs were initially induced towards HPCs by activin A, FGF-4 and sodium butyrate and were subsequently transfected with a recombinant adenovirus expressing vector pAV.Ex1d-CMV>miR-122/IRES/eGFP 9 days after induction. Cells were analysed by real-time PCR, immunofluorescence, flow cytometry, microscopy and functional assays. Furthermore, microarray analysis was performed.RESULTS:
We demonstrated that overexpression of miR-122 could effectively promote hepatic differentiation and maturation, as assessed by morphological and functional tests. The microarray analysis revealed that 323 genes were down-regulated, whereas 59 were up-regulated. Particularly, two liver-specific transcription factors, FoxA1 and HNF4a, were significantly up-regulated. Moreover, the expression of E-cadherin was dramatically increased and the proliferation of HPCs was suppressed, whereas knockdown of FoxA1 reduced E-cadherin expression and increased the proliferation of HPCs. In addition, the expression levels of FoxA1, HNF4a and E-cadherin in time-course transfection experiments with miR-122 were not significantly increased except in cells in which transfection with miR-122 occurred 9 days after induction.CONCLUSION:
Overexpression of miR-122 at an appropriate stage could promote hepatic differentiation and maturation by regulating the balance between proliferation and differentiation, as well as the balance between EMT and MET, partially through a miR-122/FoxA1/HNF4a-positive feedback loop.Palabras clave
Texto completo:
1
Base de datos:
MEDLINE
Asunto principal:
Diferenciación Celular
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Hepatocitos
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Retroalimentación Fisiológica
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MicroARNs
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Células Madre Embrionarias
Tipo de estudio:
Prognostic_studies
Límite:
Animals
Idioma:
En
Revista:
Liver Int
Asunto de la revista:
GASTROENTEROLOGIA
Año:
2014
Tipo del documento:
Article
País de afiliación:
China