Analyses of the expression of various copper transporters in SR3A and GCLC-transfected variants. Messenger RNA (A) and protein (B, C, D) levels of hCtr1, ATP7A, and ATP7B were determined by the RNase protection assay and by immunoblots using 18S RNA and β-actin as loading controls, respectively. Numbers underneath are fold increased estimated by phosphimager analyses. Panel D, Analysis of hCtr1 expression in AdE1.tTA.GCLC-transduced SR3A cells. The cells were treated with recombinant adenovirus at 50 MOI for 24 and 48 hr as indicated either in the presence (+) or absence (-) of 1 μg/ml tet. Total cell lysates were prepared and probed by using anti-GCLC, anti-hCtr1, and anti-β-actin antibodies.