CSL activates transcription
in 293T cells. (A) Activity of a CSL-responsive
reporter, (CSL)4-luc, compared to the reporter lacking
CSL binding sites, pGl2pro, upon transfection of NIH 3T3 and 293T
cells. (B) EMSAs using nuclear extracts of NIH
3T3 and 293T cells in conjunction with an oligonucleotide bearing
CSL binding sites. The major band is due to CSL by virtue of the
change of its mobility in the presence of CSL antiserum (+ αCSL), but not in the presence of control
serum (+ Serum). (C) Activity of a Gal4-CSL
fusion protein transfected into NIH 3T3 and 293T cells. Cells were
transfected with either the Gal4 site-containing reporter alone
(5×Gal4-TK-luc) or along with an expression
plasmid expressing Gal4-CSL, as indicated. Luciferase activities
were determined 2 days after transfection.