Fig. 5

Transcriptional regulation of pou5f3 by tail bud-related genes. The expression of the luciferase gene Luc-2.2, which is under regulation of the pou5f3 regulatory region, was assayed in P19 cells that had been transfected with the expression plasmids of regulatory genes. ctrl, egfp used as control. Ordinates show the expression of Luc-2.2 relative to that in the absence of effectors. Below are the amounts of transfected effector plasmids (ng/well). Total amounts of effector DNA were adjusted with pCS2+egfp. (A, B) Transcriptional regulation of pou5f3 by soxB1 genes. Luc-2.2 expression was assayed in P19 cells that had been transfected with the effector plasmids of pou5f3 and soxB1 genes by different combinations. (C) Transcriptional regulation of pou5f3 by pou5f3, sox3, and other effector genes. (D) Expression of Luc-2.2 driven by sox3 and pou5f3 in the presence of retinoic acid at different concentrations. Except for the highest concentration, RA repressed Luc-2.2 in a dose-dependent manner. All experiments were repeated at least three times, resulting in essentially the same results. The results of t test among the data marked with horizontal bars are shown. n.s., not significant; *, p < .05; **, p < .01