FIG. 6.

Transcriptional activation of the HES-1 promoter by Notch1 polypeptides. (A and C) Activation in acutely expressing 293A cells and NIH 3T3 cells, respectively. (B) Dose response in 293A cells. In the experiments shown in panels A and C, six-well dishes were transfected with 250 ng of pcDNA3 plasmids containing the indicated Notch1 cDNAs, 500 ng of HES-AB firefly luciferase plasmid, and 10 ng of pRL-TK Renilla luciferase plasmid. In the experiments shown in panel B, the amounts of pcDNA3 plasmids were varied. Cell lysates were prepared ∼48 h posttransfection. Firefly luciferase activities were normalized to the corresponding Renilla luciferase activities. Transcriptional activities were expressed relative to the normalized activities observed in extracts prepared from cells transfected with empty pcDNA3 plasmid. The results shown represent the means of three experiments.