FIG. 4.

ΔZnF AML/ETO does not repress efficiently even at high expression levels. (A) Two micrograms of MDR-1 CAT, 100 ng of CMV β-galactosidase expression plasmid, and 0.1, 0.2, 0.5, or 1 μg of the indicated AML/ETO (A/E) expression plasmids were transfected into HEL cells. At 48 h posttransfection CAT assays were performed as described in Materials and Methods. (B) CAT activity was quantitated and normalized to β-galactosidase activity.