Figure 4. Disruption of Txnrd1 in primary fibroblasts activates the nqo1 and aox1 gene proximal promoters.

(A) Experimental schematic. MEF cultures initiated from txnrd1^cond/cond;ROSA^mT-mG/+ fetuses were transduced with AdCre (experimental) or AdGFP (control). Two days later, each culture was transfected with either nqo1-luci or aox1-luci. Two days after that, luciferase activities were measured. Red or green membrane fluorescence indicates status of ROSA^mT-mG allele and, by inference, the status of the txnrd1 allele. The txnrd1 allelic status is indicated above each cell. Green slashes in cytoplasm denote transient cytoplasmic expression of AdGFP. Yellow cytoplasm denotes luciferase expression. (B) Activity of the nqo1 promoter (nqo1p). Values are in arbitrary units and represent the average of five biological replicates (i.e., MEF cultures from five different fetuses). Data were normalized to expression of CMV-luci to control for differences in transfection efficiency that might result from disruption of txnrd1 or conversion of ROSA^mT-mG. (C) Activity of aox1 promoter. Like panel (B), but using aox1-luci on three biological replicates. Error bars, S.E.M. Asterisks: *, p≤0.05; **, p≤0.01.