Time course of Wnt induced gene expression and cooperation with BMP. NCCIT cells were exposed to Wnt-3A CM, BMP-4 (10 ng/ml final concentration) or the combination of Wnt-3A and BMP-4 for the specified number of hours. Shown here are MSX1, MSX2 and ID2 demonstrating that Wnt-3A induced effects are not seen until 2 hours (which corresponds to β-catenin accumulation). BMP-4 mediated induction of MSX1, MSX2 and ID2 occurs rapidly, as early as 30 minutes and stays relatively constant. Cooperative effects of Wnt-3A and BMP-4 are not evident until approximately 2 hours. The height of the bars presents the ratio induced/non-induced, quantified by phosphoimager analysis of Northern blots and normalized to GAPDH expression measured in the same experiment. Each bar represents average values obtained from 3–5 experiments for each mRNA tested.