Fig. 7. FoxD3 and XBF2 show distinct transcriptional regulation in Slug induction. (A) FoxD3 is a transcriptional repressor. Animal caps were prepared from embryos injected with FoxD3 (25 pg; lane 3), FoxD3 (25 pg) + FoxD3-VP16 (50 pg; lane 4), FoxD3 (75 pg) + FoxD3-VP16 (50 pg; lane 5), FoxD3 (25 pg) + FoxA4-VP16 (100 pg; lane 6), and FoxD3-EnR (50 pg; lane 7) mRNAs. Animal caps were harvested at stage 17 and analyzed by RT-PCR. (B-P) Animal caps were prepared from embryos injected with control (50 pg; B-D), FoxA4 (50 pg; E-G), FoxD3 (25 pg; H-J), XBF2 (50 pg; K-M) or dnBMPR (200 pg; N-P) mRNAs, and harvested at stage 17 equivalent. Animal caps were analyzed by in situ hybridization with BMP4 (B,E,H,K,N), Sox2 (C,F,I,L,O), and Slug (D,G,J,M,P) probes. Injection of FoxA4, FoxD3, XBF2 and dnBMPR mRNA suppressed BMP expression and induced Sox2 expression. In contrast, FoxD3 induced Slug expression in the animal cap while neither FoxA4, XBF2 nor dnBMPR did.
