Figure 2.

The onset of hepatocyte nuclear factor 4 α (HNF4A) expression coincides with the conversion of iPSC-derived endoderm to a hepatic fate. (A) Diagram summarizing the results of bioinformatics analyses of enriched transcription factor binding sites by Ingenuity Pathway Analyses. Several transcription factor binding sites (yellow box) were enriched in genomic sequences encoding proteins that are induced ≥4-fold at the endoderm (blue line) to hepatic (red line) transition, which occurs two days after addition of BMP4/FGF2 between days seven and eight of the differentiation process; (B) Bar graph showing relative levels of mRNA encoding HNF4A determined by real-time quantitative PCR (RT-qPCR) (standard error of the mean (s.e.m), n = 3 independent differentiations); (C) absolute levels of total HNF4A (blue), HNF4A1 (red) and HNF4A7 (green) mRNAs calculated by real-time RT-qPCR during the differentiation iPSCs to hepatic progenitor cells; (D) Immunoblot analyses of HNF4A protein levels throughout the differentiation time course.