Both NF-κB and NFAT binding sites in the BLyS promoter are important for its activity. (A) Diagram of the BLYS promoter showing locations of site-directed mutagenesis. Luciferase activity in NHL-B (LBCL-MS) cells that had been transfected with wild-type, NF-κB, or NFAT mutant BLYS promoter-luciferase reporter constructs. (B) EMSA analysis of NF-kB or NFAT binding levels in NHL-B (LBCL-MS) cells incubated with wild-type BLYS–NF-κB or BLYS-NFAT binding site oligonucleotide probes or the corresponding mutant oligonucleotide probes from the BLYS promoter. Lamin B is used as nuclear extract loading control. (C) Luciferase activity in NHL-B (LBCL-MS) cells that had been transfected with control vector, c-rel expression vector, or NFATc1 expression vector. The error bars in panels A and C indicate the standard deviation of triplicate samples.