(A) FACS plots showing Thy1 surface levels of fibroblasts two or four days post infection with a retrovirus carrying the indicated factor (blue) in comparison to uninfected fibroblasts (red).
(B) Heatmap of expression differences between ES cells and fibroblasts (MEFs) and between fibroblast lines induced for c-Myc, Klf4, Oct4 or Sox2 expression for three days with doxycycline relative to an uninduced fibroblast control, for all genes more than 2-fold differentially expressed between ES cells and MEFs, ordered by decreasing expression ratio.
(C) Overlap of genes 2-fold up or down between ES/MEF and 2-fold up or down between MEFs induced to express Oct4, Sox2, Klf4 or c-Myc and uninduced MEFs. The first number presents the genes in the overlap, the second number the enrichment (described in Materials and Methods), and the third number log10 of the p-value. Significant enrichments are highlighted in green.
(D) R26-rtTA/wt fibroblasts were infected with three constitutively expressed retroviruses (const) and a dox-inducible retrovirus for the fourth factor (tet). Doxycycline (dox) was added until the indicated day and AP-positive colonies scored on day 25.