Expression analysis of stepwise induction of iPS cells

We were able to achieve an initial stable intermediate phase by the transduction of Oct4, Klf4, and c-Myc. Furthermore, over-expression of Sox2 in these intermediate stage cells leads to final iPS cell phase. After examining the gene expression profiles from the initial to final iPS cell phases, we have identified Sox2 downstream genes important for iPS cell induction. 4 groups of cells are analyzed. Each group contains cells from 4 indepent dishes. The four groups are: ES cells, iPS cells, intermediate stage cells (OKM cells) and MEFs