FIGURE 6 ∣.

Pf-Pou3 maintains expression of stem cell genes on loss of Oct4 in mouse embryonic stem cells. ZHBTc4 cells were stably transfected with vectors constitutively expressing mouse Oct4, P. flava Pou3 (Pf-Pou3), or empty vector negative control (EV). Stable cell lines were then grown for 24 h in the presence or absence of tetracycline (Tet). The graph shows the results of qPCR on cDNA generated from these cells measuring Oct 4-associated stem cell genes Rex1 (Zfp42), Fgf4, and Klf4, displayed as quantities relative to negative control (EV). Asterisks represents statistical significance determined with the Mann–Whitney U test (p < 0.05). Expression of target genes was significantly reduced in the absence of Oct4 and Pf-Pou3, but expression of all Oct4-associated genes tested was significantly recovered by stable transfection of mouse Oct4 or hemichordate Pf-Pou3.