Fig. 3.

Inhibition of Tat-induced HIV-1 transcription using 293T cells by iron chelators and CDK9 and CDK2 inhibitors ARC and roscovitin. 293T cells were transfected with HIV-1 LTR-Lac Z, CMV-EGFP, and Tat-expression vectors and then incubated with the indicated concentrations of iron chelators (A) or the CDK9 and CDK2 inhibitor ARC or roscovitin (B) for 24 h at 37°C. HIV-1 transcription was analyzed by measuring β-galactosidase activity. The results are mean ± S.D. (n = 4) and are typical of three independent experiments. The IC₅₀ values were calculated using Prism 3 software.