FIG. 3.

The NF-κB site mutation leads to reduced LMP1 promoter activity. (A) LRS CAT reporter plasmids encompassing the LMP1 promoter (positions +40 to −634 or +40 to −106), with and without a mutation in the NF-κB site, were transfected in the WW1-LCL cell line. The cells were harvested after 72 h and assayed for CAT activity. The relative CAT activity was obtained by measuring the percentage of chloramphenicol acetylation in the linear range of the CAT assay. The values are the means and SEM from four independent transfections. (B) Alignment of the NF-κB sequence in the LMP1 promoter in different EBV strains. The NF-κB binding site in LRS and the NF-κB consensus sequence are in uppercase letters, and the mutated nucleotides are in lowercase letters and underlined.