Research Of FoxA1 Stimulate Neural Differentiation Of Stem Cells

Transcription factor FoxA1 (previously known as HNF-3α) is belongs to the fork head/winged-helix family of transcription factors.The expression pattern of FoxA1 in developing neural tube and adult brain structures implicates its important roles in neurogenesis.To further clarify the gene regulatory mechanism of the transcription factor Foxa1 induced differentiation of the embryonic stem cell, this paper is to study the regulate role of Transcription Foxal to the Nestin expression in the neural differentiation stage of the stem cell.By using the mode1 of RA-induced P19 cell neural differentiation, we discovered that Foxal was expressed at a very high levelaccompanied by the decline of nanog, and the expresseion of neural development gene Nestin was up-regulated with the polarization of a stem cell.Therefore, we further studied the regulation of gene Nestin in the neural development.Furthermore, we investigated the change of Nestin by overexpressing and Knocking-down FoxAl respectively by foxa1 siRNA.The CHIP experiment was further conducted to verify that whether Foxa1 protein can bind to the promoter of Nestin, meanwhile, the reporter gene plasmid was constructed through the promoter of Nestin, together with the co-transfection experiment to examine the role of FoxA1 to Nestin.Transcription factor FoxAl plays a critical role during embryonic development and is activated during retinoic acid (RA)-induced neural differentiation of pluripotent P19 embryonal carcinoma cells at the early stage, which is marked by increased expression of neural stem cell marker Nestin.we have overexpressed FoxAl through an adenovirus vector in P19 cells and identified that early neurogenesis-related Nestin gene is activated directly by FoxAl.Furthermore, Knockdown of FoxAl expression during P19 cell neural differentiation results in prevention of Nestin induction. FoxAl binds to Nestin promoter at-4179 to-3919 bp region and activates the promoter in cotransfection assays.During RA-induced P19 cell differentiation, elevated levels of FoxAl increase the population of neurons.Together, our results suggest a critical involvement of FoxAl in stimulating neural differentiation of pluripotent stem cells at early stages.