Fig. 5.

Dissecting the roles of the Sp1 DBD and TAD in the regulation of copper stress-induced hCtr1 reporter Expression using a chimeric fusion approach. Recombinants encoding the chimeric transcription regulators containing DBD either from LexA (DBD_LexA) or from Sp1-ZF were fused with either VP16 (TAD_VP16) or TAD of Sp1 (TAD_Sp1). These recombinant DNA were cotransfected into HEK293 cells with their cognate luciferase reporters as indicated and treated with either 100 μM CuSO₄ or 40 μM TM for 18 h. The luciferase activities were assayed and calculated with reference to that in the reference reporter.