Cripto-1 enhances Wnt3a induced SuperTOPFLASH luciferase activity in 293T cells. (A) Full-length (CR-1 WT) and deletion constructs (CR-1 ΔEGF lacking the EGF-like domain, CR-1 ΔCFC lacking the CFC domain, CR-1 ΔEGF ΔCFC lacking both EGF and CFC domains) of human Cripto-1 in a 3×-FLAG expression vector. (B) SuperTOPFLASH luciferase reporter assay in 293T cells transiently transfected with different concentrations of full-length 3×-FLAG CR-1 WT plasmid (1, 10 and 100 ng) or with 3×-FLAG CR-1 ΔEGF, 3×-FLAG CR-1 ΔCFC, 3×-FLAG CR-1 ΔEGF ΔCFC deletion constructs (10 and 100 ng) together with 50 ng of SuperTOPFLASH luciferase vector. Cells were subsequently treated with rhWnt3a protein (50 ng/ml) for 16-20 hr. Cells were also transfected with 50 ng of SuperFOPFLASH luciferase vector and subsequently stimulated with rhWnt3a. These results are the mean ±SD of triplicates from one of three separate experiments.