FIG. 2.

Analysis of luciferase and EGR1 (early growth response 1) siRNAs activities in non-induction or induction conditions. (A) Analysis of luciferase siRNA activities in HEK293/t3g-9 cell line. HEK293/t3g-9 cells were co-transfected with pTRE3G-Luc and pRL-SV40 and the indicated concentration of doxycycline (0–100 ng/mL) was applied. Twenty-four hours later, luciferase activity was measured. (B) Analysis of luciferase siRNA activities in HeLa/t3g-luc-24 cell line. Indicated concentration of doxycycline (0–1000 ng/mL) was treated for 24 hours, and luciferase activity was measured. (A–B) For knockdown study, siLuc (10 nM final) is transfected for 24 hours and relative luciferase activities to no doxycycline condition were presented as bar graphs. Three independent experiments were performed in triplicate manner, and data in the graph represent mean±SD values of one representative experiment. (C) Analysis of siEGR1 activities in A549 cells under with or without phorbol-12-myristate-13-acetate (PMA) stimulation. A549 cells are transfected with siEGR1 under with or without PMA stimulation (100 nM, 24 hours) and target mRNA levels were analyzed by quantitative real-time reverse transcription PCR as described in Fig. 1A. Relative mRNA levels to PMA stimulation and mock transfection condition are presented. All data in the graph represent mean±SD values of three independent experiments. (A–C) Average percent knockdown efficiencies are indicated at the bottom of each condition. Student's t-test was used to compare target mRNA knockdown efficiency between non-induction and induction conditions. *P<0.01; **P<0.05.