TABLE 1

Effect of cycloheximide and MG132 on CYP1B1-mediated EROD activity

COS-1 cells were cotransfected in triplicate with vectors encoding CYP1B1*1 or CYP1B1*4, plus CPR, plus β -galactosidase. After transfection (48 h), cells were treated for 5 h with dimethyl sulfoxide (control), cycloheximide, or cycloheximide plus MG132. EROD activity/mg of protein was determined and normalized to β -galactosidase activity. Activity is expressed as percentage of CYP1B1.1-dimethyl sulfoxide control (± S.D. of triplicate values). Asterisks indicate significance of values obtained for the different treatment groups compared with control within each allelic form. Daggers indicate significance of values obtained for CYP1B1.1 vs. CYP1B1.4 within the same treatment group.