Stable Expression Of Transcription Factor FoxA1 Or FoxM1 Effects Cell Pluripotency And Differentiation Potential Of Stem Cells

Stem cells are a class of primitive cells with self-renewal and multilineage differentiation potential. Forkhead proteins are a class of very important cellular transcription factor involved in cell metabolism, growth, differentiation, proliferation, apoptosis and almost all biological processes.This study focuses on the two members of the Fox family gene FoxA1 and FoxM1 by use of P19EC cells as the research system.To explore the effects of FoxA1 on cell pluripotency and differentiation potential, the stable expression of a GFP-rFoxA1 fusion protein was established in P19 pluripotent embryonal carcinoma cells. The analysis shows that the P19 GFPFoxA1 cell line can normally expresses pluripotent marker genes such as Oct4, Nanog and Sox2. The P19 GFPFoxA1 cell line can also increase the expression of neural stem cell marker Nestin and neuron-specific marker TubulinβIII compared with P19 stem cells. Meanwhile, it can decrease activity of alkaline phosphatase and increase expression of Prominin-1 and SSEA-3 comparing with P19 cell. All these indicate that the stable expression of FoxA1 promotes P19 cells to gain partial characteristics of neural stem cells. During RA-induced P19 cell neural differentiation,TubulinβIII increase rapidly while Nanog decrease rapidly, which may indicate that P19 GFPFoxA1 cells have an earlier onset of differentiation. Thus overexpression of FoxA1 alone may promote pluripotent P19 cells transfer to neural stem-like cells.We also established a P19 GFPFoxM1 stable cell line to explore the roles of FoxM1 in the maintenance of pluripotency. It is found that, in this RA-induced differentiation process, P19 GFPFoxM1 stable cell line can hardly form embryoid bodies, the fact that expression of the pluripotent key genes such as Oct4, Sox2 lasts long indicates that FoxM1 may play an important role in pluripotency maintaining in stem cells.