Figure 4.

Msx2 promoted reprogramming by up-regulating several pluripotency-related genes. A–D, 2.5 ng/ml BMP4 and a lentivirus encoding Msx2, sh-Msx2, or sh-Smad1 were used in MEFs or during reprogramming. The expression of Cdh1, Gata3, Nanog, and Sall4 was determined with qPCR on day 4. E, a lentivirus encoding Msx2, Gata3, or sh-Gata3 was used in MEFs or during reprogramming. The expression of Sall4 was determined with qPCR on day 4. F, promoters (−1.6 to +0.12 kb relative to the TSS) of Cdh1, Gata3, Nanog, and Sall4 were constructed. The binding sites of MSX2 or GATA3 with the best prediction were indicated and deleted. G and H, the responses of WT and mutated promoters of Cdh1, Gata3, Nanog, and Sall4 to WT and mutated MSX2 were determined (G). The binding between MSX2 and regions on the promoters indicated in F was assayed with ChIP–qPCR (H). I and J, the responses of WT and mutated promoters of Sall4 to WT and mutated GATA3 were determined (I). The binding between GATA3 and regions on the promoters indicated in F was assayed with ChIP–qPCR (J). All experiments were repeated at least five times. Two-tailed Student's t test (H–J) and one-way ANOVA with Dunnett's post hoc test were used. **, p < 0.01; ***, p < 0.001; ns, not significant.